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PollyMobiles Rebuild

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pollyp

pollyp

Club Member
tday i measured the bores of the forged engine just to double check.

previously measured the forged pistons to have the widest diameter of 71.4mm

JE guideline says bores measuring 2.5 - 3.625" (63.5 - 92.075mm) need a minimum piston to bore clearance of 0.003 - 0.0036" (0.0762 - 0.0914mm)

measured the bores and plotted on a radar graph to visualise any variations.

cylinder 1: round n tight at TDC, bowls out at MDC then ovals slightly at BDC near the main bearings. the tightest point is 71.493mm at TDC (clearance of 0.093mm, just above minimum)

1.jpg


cylinder 2: slight ovality laterally, again starts tighter at TDC, bowls out MDC but ovals slightly at BDC. tightest point is 71.496mm (clearance of 0.096mm)


2.jpg


cylinder 3: nice even n round, same bowling pattern. bore is 71.506mm (clearance of 0.106mm)


3.jpg


cylinder 4: round n tight at TDC, bowls out abit at MDC but then ovals longitudinally at the bottom near the main bearings like cyl 1. tightest point is 71.498mm (clearance of 0.098mm above minimum)

4.jpg


also updated the "before machining" bore measurement graphs on post #3259
 
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pollyp

pollyp

Club Member
I readjusted all the graphs onto the same difference scale so here we can see how the re-bored cylinders are rounder than previously

compare.gif
 
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OP
OP
pollyp

pollyp

Club Member
to calc the ring endgaps, JE guidelines says the minimum gaps for street moderate turbo use
:
top = per inch of bore x 0.0050"
2nd = per inch of bore x 0.0055"
oil = 0.0150"

averaging the TDC bore measurements for each cylinder:
cyl1: 71.496mm
cyl2: 71.499mm
cyl3: 71.508mm
cyl4: 71.503mm

so the minimum end gaps for each cylinder should be: (top, 2nd, oil) in mm

cyl1 = 0.3575, 0.3932, 0.381
cyl2 = 0.3575, 0.3933, 0.381
cyl3 = 0.3575, 0.3933, 0.381
cyl4 = 0.3575, 0.3933, 0.381

i inserted each ring with their gap positioned where it'd be during assembly and measured the gap (top, 2nd, upper oil, lower oil) in mm

cyl1 = 0.3560, 0.2290, 0.229, 0.178
cyl2 = 0.2540, 0.2290, 0.279, 0.279
cyl3 = 0.2790, 0.2030, 0.279, 0.305
cyl4 = 0.2790, 0.2790, 0.330, 0.305

apart from the top ring of piston 1 they're all still way too tight, maybe it's cos I also lubed the bores with a little wd40?
even if the thin oil slightly reduced the values it's still wayy off.

the piston to bore clearance is correct but i think I'll need to get hold of a ring end grinder tool to tweak each ring?

...ps took bettter readings later on post #3515 below
 

Low Rider

Poindexter
Founding Member
Moderator
Club Member
What's JE's recommendation on bore tolerances Paul?

CP, for example, specify the final bore needs to be less than + 0.0002” out of round, checked 360 degrees around the bore from the bottom to the top of the cylinder.
 
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pollyp

pollyp

Club Member
i,ve always done mine 10" thou paul, which yours are over eh :)
that's for normal n/a cast pistons ain't it?

mines a forged piston of different material properties and this pro-ring's minimum end gap for using a turbo setup on track is prob different to a stock n/a ring?

thinking bout ur past quote that the endgaps may widen abit during bed-in, I just spotted this controversial article which states:
  • avoid honing a used bore when re-ringing cast iron rings
  • only hone with chrome rings and rebores
  • ring end gaps and the bore dia on a rehone will increase slightly to its final measure once all the tiny hills n valley highspots have worn down to a smooth sealing bore
http://www.snowvalley.20m.com/bikes/dnthone.htm

i wonder, are the guideline minimum end gaps suppose to be measured after bedding-in where the clearances stabilises?

so i run the rings as they are under low load/heat till they're mostly bedded, then strip it all apart n recheck the final end gaps?
 
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pollyp

pollyp

Club Member
What's JE's recommendation on bore tolerances Paul?

CP, for example, specify the final bore needs to be less than + 0.0002” out of round, checked 360 degrees around the bore from the bottom to the top of the cylinder.
dunno, doesn't say

0.0002" is 0.00508mm
most of the ovalness is at BDC and the worst is on cyl4 with 0.005 difference between highest n lowest reading so maybe within spec
 
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pollyp

pollyp

Club Member
figure I need to remeasure the end gaps with a dry bore again cos noticed the oil rings were slightly oval and letting light pass through the sides giving a false tight reading (top & 2nd rings fine). when i push the sides of the oil rings against the bore like the expansion ring, i could fit or wedge a larger feeler gauge in.

frank, so is it ok to just slightly bend n shape the oil rings tighter by hand to fit the bore?
or shall i leave it and just wedge the feeler in to push the rings out to check the gap then let the expander ring sort out the out-of-round?
 

frank

Club Member
i would let the expander ring do the pushing on new rings personally paul, i tweak the rings only on my partworn ones, they tend to sag after many heat cycles eh (and i stretch the expanders too nowadays) :)
 
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pollyp

pollyp

Club Member
yep the mistake of oiling the bores with wd40 and altering the orientation of the rings definately affected the readings.

now with dry bores and all the ring gaps positioned at 12 oclock the readings in mm are (top, 2nd, upper oil, lower oil)

cyl1 = 0.2790, 0.2790, 0.356, 0.356
cyl2 = 0.3050, 0.3560, 0.330, 0.356
cyl3 = 0.3050, 0.2790, 0.356, 0.356
cyl4 = 0.3560, 0.3050, 0.381, 0.356

again the recommended gaps are 0.3575, 0.3932, 0.381 (top, 2nd, oil)

they seem ok considering that the gap will widen slightly once fully bedded-in.
so its a case of just a normal non-intensive bedding in process, avoiding long WOT cos it could heat up and bind the rings before the gaps have opened up.

the top rings fit nicely, no light gaps

DSC07638.JPG


same with the 2nd ring

DSC07639.JPG


here's the oil rings with the slight oval gaps. once i wedge a larger feeler gauge in the endgap it seals better

DSC07640.JPG
DSC07641.JPG
 
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OP
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pollyp

pollyp

Club Member
here's the reply from JE

"Ring end gap is completed prior to break in and running of motor. I have not heard of any body disassembling engine to reset the ring gaps.
Gaps are determined by application.


Ring ends will butt if they are not filed prior to running of engine. You will not be happy with the result of that. Keep in mind that the piston grows along with the bore and in many cases it grows faster than the adjacent bore."

if I need to file the gaps to the minimum clearance before running, it's gonna have to be next year when i can be bothered to buy a ring filer n meticulously fine tune it.
for now it's gonna be in storage.

flushed & cleaned the block & bores from the honing muck

DSC07642.JPG
DSC07644.JPG


when fitting the pistons, i oiled the bores and only the bottom half of the ring compressor so that once installed, only the bottom oil rings are wet while the upper compression rings are drier.

crank on

DSC07645.JPG


girdle fitted

DSC07646.JPG


spins nicely

DSC07647.JPG


cylinders 1-4

DSC07648.JPG
DSC07649.JPG
DSC07650.JPG
DSC07651.JPG


k bottom assembly bagged up for storage
 
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OP
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pollyp

pollyp

Club Member
time to swap the front coils back to 4kg and an annual inspection

when i first fitted the 6kg coils the car sat at 98, 99, 118, 123mm (rear left, rear right, front left, front right) with a full tank and no driver weight

now a year later she sits 105, 103, 102, 105mm (rear left, rear right, front left, front right) with 1/2 tank and no driver weight. considering the raised height from reduced weight, the front coils have sagged bout 10mm till the front & rear match height. with a full tank it's prob closer to 100mm all round.

removed the front right strut

DSC07652.JPG


the covers kept it in almost pristine condition, just light dusting

DSC07653.JPG


ziptied the boot to the damper body so it won't expose the damper shaft

DSC07654.JPG
DSC07655.JPG


the front left strut is a little bit more exposed n dusty n slight moisture rust on the chipped edges where the tools been used. good clean with carb cleaner n wd40 sorted it. cleaned n reoiled the pillowball strut tops.

DSC07656.JPG


coil rings set to the same config as the prev 4kg setup.

prev 4kg front coils used for a year sat at 98, 98, 98, 97mm (rear left, rear right, front left, front right) with full tank and driver weight.

and now she sits 107, 104, 116, 115mm (rear left, rear right, front left, front right) with 1/2 tank and no driver weight. considering the raised height from reduced weight, the stored 4kg front coils has expanded by bout 10mm, interesting. so once these coils have fully settled in or fully relaxed they differ by 10mm.

went for a brief drive and shes now at 106, 104, 112, 112mm (rear left, rear right, front left, front right) with 1/2 tank and no driver weight. dropped 3mm after a short drive. give the springs time to settle down
 
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OP
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pollyp

pollyp

Club Member
clutch pedal is beginning to creak after few mins of driving so I removed the cable & pedal to assess

DSC07657.JPG
DSC07659.JPG


this is the culprit. the same sleeved rivet pin design used on the other clutch fork end which tends to wear thin and suddenly sheer off when using a heavy duty pressure plate. the sleeve has worn off and the pins creanking on the pedal arm.

DSC07660.JPG


the rubber cusion abit worn but not an issue

DSC07661.JPG
DSC07662.JPG


the bi-stable helper spring acts on the pedal arm through a nylon fitting, smeared some grease on it and oiled the pedal pivot and the inner cable with engine oil

DSC07663.JPG


removed the worn pin

DSC07664.JPG


tapped an m6 thread on the small hole. found this bolt with a 5mm smooth shank so the pedal arm has a smooth surface to slide on rather than a coarse thread.

DSC07667.JPG


hooks up like this

DSC07668.JPG
DSC07669.JPG


during fitting i couldn't feed the end through the hole cos of the bulky nut&bolt so remove the bolt, feed through hole, refit the bolt and then fit the bracket onto the bulkhead

DSC07670.JPG


after few mins test drive ooh she works smooth as butter and silent :cool:
 
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funky2nite

Ex. Club Member
Your blog is something from out of this world mate! I've been straight on like the past2 and ahalf hrs reading through!

you're an inspiration here at micra club. I've never know of such hidden treasure here honest! If I may ask, initiallly you mentioned of in possession of a degree in car design.. Does that go technically mechanical too? Because it must in someway or another..you've mastered the whole 'mechanic' 'electrician' 'body work' roles man!

something must have fuelled your knowledge up to this standard, how bad I'd love to do the same with mine.. but I'm yet too far from being as skilled as you are..

god bless you mate!

Ian - Malta
 

SirChris

Educated Bodger
Your blog is something from out of this world mate! I've been straight on like the past2 and ahalf hrs reading through!

you're an inspiration here at micra club. I've never know of such hidden treasure here honest! If I may ask, initiallly you mentioned of in possession of a degree in car design.. Does that go technically mechanical too? Because it must in someway or another..you've mastered the whole 'mechanic' 'electrician' 'body work' roles man!

something must have fuelled your knowledge up to this standard, how bad I'd love to do the same with mine.. but I'm yet too far from being as skilled as you are..

god bless you mate!

Ian - Malta
Inspiration and royal pain in the arse for setting my goal to meet his standards so high :D

I will get there Paul.. I will get there... haha I remeber you under my bonnet fixing my car at JAE, the rest of us being pit crew :p
 
OP
OP
pollyp

pollyp

Club Member
Your blog is something from out of this world mate! I've been straight on like the past2 and ahalf hrs reading through!

you're an inspiration here at micra club. I've never know of such hidden treasure here honest! If I may ask, initiallly you mentioned of in possession of a degree in car design.. Does that go technically mechanical too? Because it must in someway or another..you've mastered the whole 'mechanic' 'electrician' 'body work' roles man!

something must have fuelled your knowledge up to this standard, how bad I'd love to do the same with mine.. but I'm yet too far from being as skilled as you are..

god bless you mate!

Ian - Malta
hey thx so much for the compliment Ian ;)

i think my current ability is due to the range of skills n interest i gathered over the years.

as a kid armed with a screwdriver i luved taking stuff apart and finding how things work/assemble. may have broken alot of stuff as a kid but thats how you learn knowledge n logic n remember how things assemble and keeping an organised methodology which then results in fixing more stuff as you gain experience.

in school i luv science which is prob where my methodical experimentation & organised documentation came from. plus design tech which is where my passion to 'apply' the learned science and improve/upgrade stuff comes from. always luved sketching and designing cars inside out as a hobby.

when i got my first mountain bike my hobby was in maintaining and overhauling the whole bike. it was like an advancement of my prev interest to take stuff apart, clean n reassemble.
disassembly is easy. the skill n challenge of a mechanic was to remember or figure how all the many parts suppose to go together and work properly.
this was prob the first time i had a bicycle haynes manual to follow and would start off easy like handle grips n brakes and work through the whole book to the advanced stages that need special tools and doing it so often it becomes 2nd nature.

learned gcse electronics in college

to pursue my luv for car design i did a degree in automotive product design where you learn bout component layouts, materials & manufacture, hand rendering, CAD, prototype model making, as well as some design assignments. was gonna be a car designer but tbh wasn't gonna happen cos its extremely difficult to get into.

so pursued more towards product design and did an MA in design which eventually led me to getting my first prof job as a product designer yay.

now bare in mind at this point I didn't have a car yet (used bicycle on train) and didn't have a license till i finished my first degree so had no idea bout working on a car.
until the oppurtunity came where my sister was about to trade in the family micra for a new car (she was only gonna get £200 for it) so I brought the micra off her for cheap as a first car but mostly as a personal "project" cos it was in poor shape and thought needed an overhaul (me being a perfectionist) and this would be a new adventure armed with a haynes manual and few spanners/socket (just like my first bike) and that, fellas, is where my blog began :)
 
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pollyp

pollyp

Club Member
the overall afr's been running abit rich recently in the cold weather since its running open-loop without an O2 to correct it and the plugs are showing a light hint of soot on one side of the white clean insulation. so retweaked the injector multiplier till its running abit more towards 14.7
 
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pollyp

pollyp

Club Member
recently noticed camskill has ran out of T1R and will shortly need to replace these as its getting near to snow time.
so looking elsewhere would be round £40+ but cheapest i found was from tyre wizard £150 a set, ordered.

I've also been thinking & researching into setting up the coilovers with what's called Zero Droop whereby at static height the damper or suspension is almost at max droop/extension.

on circuits especially during low speed braking hard turns i used to find the rear pops up sky high and then the inside wheel side pop up high n understeers mid-turn (only resolved with alot of trail braking).

i fitted harder 6kg front coils in hope of reducing the front end rolling over during trail brake but seemed to induce exit understeer.

by droop limiting, during turning, the inside wheel arch cant move up anymore, reducing roll n weight transfer n all sorts stuff.
read a good guide bout it sumwhere, will post later.
here 3rd post:
http://www.apexspeed.com/forums/showthread.php?t=54262

only way to lift both the inside wheels would be when there's enough lateral force pushing the cars high CG over till all the body weights been transferred to the outside wheel but before that happens the outer tyres prob overloaded by then and would rather slide than grip (ie too fast for corner)

anyway Q is I remember someone prob on ciscos site who took his k11 on slalom courses and he fitted these blue droop limiting straps to his rear axle (either to lower or preload the coils) but can't remember or find who it was.
anyone remember?
 
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pollyp

pollyp

Club Member
drawn afew diagrams of how i could limit droop

this is my current setup. at static ride height the damper piston sits bout 1/2way.
it can droop down 50mm to maintain tyre contact over say a pothole but this droop allows the inside arch to heave up n shift CoG etc.
it can bump up 40mm till it hits the bumpstop and prevent the tyre from striking the arch

1 normal setup static height.jpg

2 normal setup top out.jpg

3 normal setup bottom out.jpg


at static height if we just lower the front & rear damper body till it tops out (maintain the front ride height by screwing the front spring perch & hub together up the damper body (will take quite an effort screwing that ring 50mm against a stiff spring), till spring preload = corner static weight), the zero droop should prevent the wheel arch inside the turn circle from lifting up until the all of the weight has been transfered to the other opposite wheels but the increased bump travel now allows the loaded wheel to be forced up unlimited until either the tyre strikes the arch or the spring binds up, both are bad

4 zero droop setup no packer static height.jpg

5 zero droop setup no packer strike.jpg


so as well as lowering the damper body we need to lower the bumpstops the same distance by adding "packers / bump stop spacers" (in grey) to maintain the original bump travel

6 zero droop setup with packer static height.jpg

7 zero droop setup with packer bump.jpg


not sure if using the dampers top-out as a droop limiter could potentially damage the piston if allowed to say rebound at full wack into a pothole/ditch after hitting a bump, or extremely sudden directional change (tight s-bend), will only be setting up zero droop on a smooth track.
so an alternative method is to leave the current setup at static height and anchor a droop limiting strap between the chassis and the hub/axle. it's also much easier and faster to change between normal droop and zero droop on the track

droop strap setup static height.jpg

droop strap setup bottom out.jpg


ah just found that some dampers may have a top-out spring to cusion n stop the piston crashing up against the damper top
 
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pollyp

pollyp

Club Member
just looking through & photoing the many boxes of parts in the garage I've gathered up over the yrs of the polly proj gettin ready to sell on and my god the amount of stuff just never ends :p
lots of left over bits to photo n measure n post up in buy sell. limbs too cold tday, gonna have a cuppa before carrying on
 
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pollyp

pollyp

Club Member
phew finally managed to put up most of the spare bits in buy sell now.

F/S: Skyline R33 GTS-T fuel pump motor with k11 pickup
F/S: Spitfire HT Leads for k11 micra non-coilpack
F/S: Janspeed Manifold for k11 micra
F/S: k11 1.3 NATS1 ECU with Nistune Daughterboard
F/S: Bilstein Streetline Suspension Lowering Kit

still got all the spare induction pipes n old Jun flywheel/helix clutch to do

btw this old rusty rear disc caliper, what shall I do with it?
DSC07729.JPG
DSC07731.JPG


it needs a proper rebuild and prob abit rare to find. shall I post on buy sell for someone who may wanna rebuild it up, doubt any brake rebuilding company would give me anything for it, or just chuck it?
 
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Limiting droop has the effect of the anti roll bar suddenly becoming infinitely stiff in a corner where the inside wheels drop far enough for it to occur. But don't think about it that way, it's far too complex and blows yor mind. It also has the effect of counteracting the jacking force the chassis experiences where the inside of the car keeps raising as cornering force increases. Instead it turns into a lowering force on the outside of the car. All good you may think, yes until your droop limiters force your car to corner on its bump stops, also a disaster. It's a powerful adjustment used properly though fraught with potential and unforseen errors.

Zero droop will significantly adversely affect the capabilities of your car Polly. The capability for a tyre to generate grip increases as load is applied to it. If your car has zero droop it will have no ability to shift its Cg therefore applying load to the outside wheels. A simpler visualisation is to consider your car under full braking. The rear will not rise therefore significantly reducing the front grip increase effect of the weight shift forward. Your brake bias would effectively be all wrong and you would experience front lockups.

This parameter is easily adjustable on RC model circuit cars. The droop limiters are a significant tool in the setup of those cars. I have spent 15 years at the top level of that sport in 1/10th scale and, although there will always be people out there with different opinions, my rule of thumb is to begin by splitting the suspension travel 70/30 ie 70% bump and 30% droop. The same setting front and rear initially. This gives us a balanced handling from where further assesments and adjustments can be made. Sometimes, as the grip level goes up and down this ratio gets modified which is why it's adjustable. A model cars bump travel is usually more than a 1:1 scale so we may have to modify the rule of thumb or the way we 'read' our 1:1 car to reflect that. You see a model can sit the chassis on the floor without its shocks being closed yet. I'd like to know whether this is the case for a Micra but I very much doubt it. For the purpose of setup this position is what I would refer to as full bump travel, regardless of any bump stops etc (100%). Can you measure up a micra this way? ie remove the springs, rebuild the car and articulate it? The Jack certainly has to be made to dissapear from under the car and then reappear under there during the experiment. Next to consider is our ride height. A 10th scale model has a flat chassis plate so it's easy to measure, a Micra does not! (so we would have to assign it one) On a 10th scale model 7mm would be high, but lets assume that's our desired ride height, from the floor. I would then dial in an additional 3mm of droop travel, again measured under the from the floor. Thus giving the car 0mm/7mm/10mm from bottom to top.

In your case you say you have 40mm bump travel and 50mm droop travel these are no doubt shock travel and not wheel travel and are interfered with by bump stops and vehicle geometry. I presume this is the case at both the front and the rear? If so it stands to reason the inside of your car can raise 50mm in a turn. That's quite a lot when scaled to 5mm on the model car. It also suggests the sills can only go down 40mm which is also far less than our ground clearance. The adjustment, removal and replacement of bump stops make your figures somewhat 'grey' in nature. My rule of thumb is purposefully works on wheel travel making it more black and white and can therefore be applied to all cars regardless of geometry and construction. Droop travel can be set differently front and rear to induce under/oversteer characteristics in limit cornering situations, ie most of the time!

I would begin your project by simultaneously jacking both ends of the car until the tyres are just touching the flat floor and look at it from the side to determine which end has more and less droop travel. I would note the distances from the ends of the sills to the ground at all four corners, they may not match perfectly! Put the car back on the ground, settle it's suspension and roll it back an forth a little then measure the same positions again. Then I would know all 3 of my critical values without dissasembling the car and my RC car rule of thumb could work at full size. My droop travel (max Ground Clearance) my (Ride) ground clearance and my theoretical max bump travel (presumed to be when the sills are on the floor) I would then calculate and address which end of the car has too much droop travel. My 10p would be on it being the back. ;-)

I have spent lots of time considering this aspect of my own Micra and how I would like to solve the issue of droop limitation at both ends of the car. I just wouldn't benefit from doing so because I don't track the car. In summary I forecast your car will significantly benefit from droop limitation but not by limiting as much as you are proposing, that's too much and that it will be the back end which nets us the biggest handling changes.

Go to it Mr P, get us some new numbers please. Good luck finding a flat floor to do it on to begin with! There is a good vid on Youtube that can help with this though.

Can somebody link me to this slalom video of ebbdudes, I noticed it in the maximicra project but I never able to watch it, I presumed it had been removed!?
 
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pollyp

pollyp

Club Member
DSC07739.JPG


ok just measured the Jun flywheel & helix clutch before selling.

a new helix 3 pad clutch disc is 7.7mm thick and min 6.05mm at the rivets (1.65mm operating thickness)

after 13k the disc is now 7.1mm(63.6%) 6.95mm(54.5%) and 6.95mm(54.5%) (inner mid outer)
the PPlate is worn by 0.45mm 0.37mm 0.36mm (inner mid out)
the 30k used flywheel is worn by 0.37mm 0.21mm 0.27mm (inner mid out)

the gap between the flywheel and PP is tightest at the mid point, the outer edge is 0.05mm wider and the inner edge is 0.24mm wider.

comparing the disc thickness to the worn metal clearances it seems the glazed clutch is mainly contacting at the middle and outer points while the inner point is just slipping n wearing away fast.
 
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pollyp

pollyp

Club Member
the closed-loop afr once again getting abit rich in the dense freezing air so went out to retune the map.

think the injector latency is abit offset cos cruising in 5th it runs 14.7 as the fuel map shows but when I shift down 4th, revs raise and maintain speed its at bout 15.6afr, into 3rd n higher rev she runs bout 16.1afr, getting leaner the closer i get to zero load/high rev.

above the zero load region when accelerating on boost the mixtures spot on.

idles at 14.7 but free reving in neutral it just leans out hugely round 17afr+

also tested the boosts reading behavior:
-21psi at idle
-24psi at 3k in neutral
-14psi cruising at 3k/70mph in 5th
10psi from 2.8k in gear
10psi from 5k in neutral
 
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pollyp

pollyp

Club Member
Thought I'd post up my findings about Nistune that i wrote to Stani

The minus and O key follow certain rules.

- minus key
only works in closed-loop cells between 128 to 255 raw value

O key (switch between open/closed loop)
if raw values between 0 - 63 (open-loop) = add 192 (close-loop region)

if raw values between 192 - 255 (closed-loop) = subtract 192 (open-loop region)

RAW values converted to A/F ratio
0 to 127 = 14.70 to 7.38 a/f open-loop
128 to 255 = 29.40 to 9.85 a/f closed-loop O2 corrected
 

funky2nite

Ex. Club Member
hey thx so much for the compliment Ian ;)

i think my current ability is due to the range of skills n interest i gathered over the years.

as a kid armed with a screwdriver i luved taking stuff apart and finding how things work/assemble. may have broken alot of stuff as a kid but thats how you learn knowledge n logic n remember how things assemble and keeping an organised methodology which then results in fixing more stuff as you gain experience.

in school i luv science which is prob where my methodical experimentation & organised documentation came from. plus design tech which is where my passion to 'apply' the learned science and improve/upgrade stuff comes from. always luved sketching and designing cars inside out as a hobby.

when i got my first mountain bike my hobby was in maintaining and overhauling the whole bike. it was like an advancement of my prev interest to take stuff apart, clean n reassemble.
disassembly is easy. the skill n challenge of a mechanic was to remember or figure how all the many parts suppose to go together and work properly.
this was prob the first time i had a bicycle haynes manual to follow and would start off easy like handle grips n brakes and work through the whole book to the advanced stages that need special tools and doing it so often it becomes 2nd nature.

learned gcse electronics in college

to pursue my luv for car design i did a degree in automotive product design where you learn bout component layouts, materials & manufacture, hand rendering, CAD, prototype model making, as well as some design assignments. was gonna be a car designer but tbh wasn't gonna happen cos its extremely difficult to get into.

so pursued more towards product design and did an MA in design which eventually led me to getting my first prof job as a product designer yay.

now bare in mind at this point I didn't have a car yet (used bicycle on train) and didn't have a license till i finished my first degree so had no idea bout working on a car.
until the opportunity came where my sister was about to trade in the family micra for a new car (she was only gonna get £200 for it) so I brought the micra off her for cheap as a first car but mostly as a personal "project" cos it was in poor shape and thought needed an overhaul (me being a perfectionist) and this would be a new adventure armed with a haynes manual and few spanners/socket (just like my first bike) and that, fellas, is where my blog began :)
Eyy mate, I didn't notice your reply until now darn me...

firstly warm greetings to you and everyone here at the forum, I appreciate the candid way you've expressed yourself :)

your story kind of closely relates to mine, with distinct difference that even from an early age...heh up till now, I still do tweak a lot of stuff but yet manage to repair just a slight percentage. Keep up the good work here at the forum, you keep surprising me, this evening just got to another post of yours through someone's thread, which ended up taking me an hour or so of reading through..even though I don't understand every technicality there is...

Cheers mate!
Ian - Malta
 
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pollyp

pollyp

Club Member
Eyy mate, I didn't notice your reply until now darn me...

firstly warm greetings to you and everyone here at the forum, I appreciate the candid way you've expressed yourself :)

your story kind of closely relates to mine, with distinct difference that even from an early age...heh up till now, I still do tweak a lot of stuff but yet manage to repair just a slight percentage. Keep up the good work here at the forum, you keep surprising me, this evening just got to another post of yours through someone's thread, which ended up taking me an hour or so of reading through..even though I don't understand every technicality there is...

Cheers mate!
Ian - Malta
hey cheers Ian
just like with any skills, more practice = more efficient at succeeding
hav a jolly chrimbo ;)
 
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pollyp

pollyp

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Wideband free-air configuration trick

hey i thought I'd add this tip I just figured.
A wideband sensor would require an occasional calibration so that it gives an accurate gas reading.

This is done by removing & exposing the sensor to outside air and telling/teaching/calibrating the controller that this is definately 20.9afr free-air to compare its gas readings against, before reinstalling.

removing the sensor each time is quite inconvenient n I recently pressed the gauge button accidentally to trigger a re-calibration mode when in fact the exhaust was still bout 19afr so the reading was well-off.

then I remembered that whenever the engine is over-running (closed TPS, in-gear and above 1500rpm) where the injectors shut-off, the engine simply becomes an air-pump instead of an internal combustion engine so the exhaust gases are purged out of the pipes replaced with air and so the gauge would've read 20.9 = free-air, right condition to perform re-cal.

so whilst on the move in high-gear I close the throttle to shut the injectors, press the gauge button to trigger recalibration, once done I carry on and it reads correctly
 
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pollyp

pollyp

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I've just been thinking that it would be useful during trackdays if I could monitor & record the temperature distribution of each tyre when on-track to tune the tyre pressure and camber.

old method is to stick probes on the tread after pitting to measure the core temperature but would be slow n useless cos it would've cooled right down during the in-lap.

i know onboard infrared thermal cameras are used in motorsport to monitor tyre surface temps.
now proper thermal cams are not cheap but i wonder if the "remove webcam IR filter" mod mounted under the chassis would be sensitive enough to pickup temperature differences across a hot tyre?

the next problem is how to cost effectively record multiple cameras:
1. buy 4 £40+ miniature self-contained action-cams and tediously post-edit them together
2. plug 4 £5 composite-output mini-cams into a dedicated multi-channel Portable Video Rec = £200+
3. plug 4 £5-10 usb mini webcams, like these below, into a laptop usb hub



think I'll convert a cheap webcam n test if it can see the difference between e.g. a mildly hot radiator and cold wall

next is figure if there's a software that can record least 4 simultaneous webcams into seperate or preferably one combined video. anyone tried it before?
 
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pollyp

pollyp

Club Member
hmm ok prob have to scrap that idea cos even though my endoscope auto-adjusts brightness and can pickup infrared, when testing with my gas solder iron it wouldn't pickup the difference until i could just see the metal glow faintly orange and really hot so normal camera won't be sensitive enough

...or prob need to add a visible light filter

btw FLIRs site shows some interesting onboard vids
http://www.flir.com/thermography/americas/us/view/?id=58154
 
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pollyp

pollyp

Club Member
right tday i went n brought a cheapo £7 tesco webcam and a £3 disposible camera for the film (oddly the same type & exp of film catridge on its own is £5? huh)

note: found new film doesn't work cos its just milky see-through opaque, meh. instead u need the very black overexposed bits of a developed old film (ie. the very end strips of old photo negatives) or use the 2 opposing polariser film on LCDs to block out all the visible light.

took the cam apart, removed the red tinted IR filter, replaced with the black film negative (required least 4-5 layers to block enough light) booted up the software and hey presto it see's infrared :)

tis interesting walking round the house picking out hotspots like lamps n cooker flame and how LCD screens are just plain white (backlighters)

bad news is that these cheap CCD are only good for detecting high intensity IR (very hot sources least bout 200C) or bright scenes.
Trying to detect tyre temp (upto 60C) is like trying to film a really dark night scene, wacking up the cheap quality CCD sensitivity just induces noise. a low noise highly sensitive CCD is required.

another note is that external IR sources from lamps, sun, reflection etc can also easily interfere n drown out the picture. needs more testing
 
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pollyp

pollyp

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went for a drive tday and I think the inlet valve stem seals leaking cos it seems to be collecting some oil during prolonged downhill high-rev high vacuum overrun and then the moment she resumes combustion there's a brief mist of oily smoke.

so a worn rear main seal and worn stem seals are prob contributing to the slow oil loss
 
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pollyp

pollyp

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turbo was rebuilt with new bearings and seals and a stepped turbine seal ring.

it doesn't smoke at all during cold/hot crank, cold/hot idle, WOT pulls, cruising, normal up/down shifts.

its only after a long downhill over-run that it burns the small excess oil once it begins firing, and also smokes when revving to the limiter in neutral but slowly goes away shortly after closing the throttle and the excess oil is burnt away.

all plugs appear perfect, good even cyl compression
 

frank

Club Member
turbo was rebuilt with new bearings and seals and a stepped turbine seal ring.

it doesn't smoke at all during cold/hot crank, cold/hot idle, WOT pulls, cruising, normal up/down shifts.

its only after a long downhill over-run that it burns the small excess oil once it begins firing, and also smokes when revving to the limiter in neutral but slowly goes away shortly after closing the throttle and the excess oil is burnt away.

all plugs appear perfect, good even cyl compression
genuine parts tho paul ? my 1st TD05 started to smoke only after a long lift (after 3 or 4 months) because of shaftplay, and the turbine was wet with oil (hence the plug colour being ok, ie, burned in the downpipe and not burned in the engine).
my shaft had some wear, so a rebuild kit/bearings would,nt have cured all the shaft play eh, and would,ve been short lived :)
 
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pollyp

pollyp

Club Member
I think trying to convert a cheap webcam, IR cam or low-light cam into a sort of thermal cam is gonna be quite difficult n expensive n prob overkill.

yes would be a luxury to get a thermal movie of each tyre so i can accurately see the temp distribution of each part of the tyre but tbh all I really need is to measure the inner, mid, outer spot temps of each tyre on the track.

so maybe a better option is to buy a dozen £5 IR thermometers,
bundle all the displays together in a box,
point 3 IR detectors at each tyre,
wire em upto the bundle of displays,
point one of my cameras at the box to record all the readings
 
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