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micra madness k13 edition

frank

Club Member
the miller cycle bit is just an offset crank i think mik, for a longer power stroke (like the prius)
a knock sensor will be fitted no doubt, so you will have some protection eh :)
 

SplanK

Site Supporter
The miler cycle is more or less an alteration in "normal" valve opening timing.

Its a solution where the intake value remains open for part of the compression stroke to reduce pumping losses. I think about 1/3rd of the upstroke has the intake valve open.

This is why the engine is boosted and also has a compression ratio of 13:1 to aid performance otherwise it would be a bit of a dog! But its also why Nissan didn't turbo this engine, because there would not be enough exhaust gas pressure to efficiently spin a turbo low down.

There are going to be 2 things with this engine that's going to easily increase power. Cam modification and super charger pully modification. Care needs to be taken to not over rev the super charger though!

One of the little annoyances about the DIG-S is its obviously geared to be a enviro car. The charger will turn off when it thinks its not needed but when it it, it might not switch on until a gear change.
 

frank

Club Member
yes my bad, i was thinking atkinson cycle, the ecu probably uses the vari valve control for the late opening inlet (but only if the s/c is running)
 

SplanK

Site Supporter
In fact, just read about Atkinson Cycle and you are not far off.
Essentially its the same principle, apart from miller is just boosted to make up for the loss of cylinder pressure due to the late closing intake value. The charger shuts off and bypass values kick in to allow the engine to run N/A for when the extra power isn't needed

Anybody hooked up a boost gauge yet to see what's going on? I keep meaning to however life keeps getting in the way of tinkering!
 
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mik

mik

Anybody hooked up a boost gauge yet to see what's going on? I keep meaning to however life keeps getting in the way of tinkering!

i did just for testing. i attached it before the purge valve (see my pic) boosted up to 0.4 bar and idle was about -0.7 bar vacuum. have to measure it while driving, didn`t have a long pressure hose :) will install one in the car, if i figure out how i want it to look like :D

k13_007.jpg
 

SplanK

Site Supporter
0.4bar is around 6psi... other than the fact is missing a piston, and chunk of the compression stroke, a low boost figure explains the relatively low HP figure for a modern boosted engine!

I dare say a couple more PSI wont do much harm... if we can figure out much smaller the pulley needs to be!
 
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mik

mik

well 6psi if i was measuring correct, we can go for shure if i test it while driving, maybe i can do it tommorrow. i wanted to insert the gauge in the heater holes in the middle of the dashboard. i removed the middle dash and measured the holes, they are 70mm, which is unfortunatly too big, even for a 60mm gauge :( i dont want to have a a-pillar pod or something on my dashboard like a gauge.

anyway: i`ve ordered some wheels today ;)
 

solarice

Ex. Club Member
I'm pretty sure there's a sc pulley calculator online somewhere...i seem to remember downloading it, but i've had a look and i don't have it, so it was either deleted or i've dreamed it :D

Can you not trim ring / spacer the gauge? or would it look odd.

OOoooh wheels. :)

Also wondering how much the nismo ecu (which i forgot about earlier) is tweaked for these.
 
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mik

mik

I have a look today, on how to put the gauge in, i think it wouldn`t look good with a ring :(
yes went with 7x17 alloys and 195/40/17 wheels :D
 

frank

Club Member
0.4bar is around 6psi... other than the fact is missing a piston, and chunk of the compression stroke, a low boost figure explains the relatively low HP figure for a modern boosted engine!

I dare say a couple more PSI wont do much harm... if we can figure out much smaller the pulley needs to be!
yes, the dynamic c/r will be nearer 9:1 with that late valve closing eh,i bet the taiwan guys are upping the boost already :)
 
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mik

mik

yeah the only good source is the thai march scene, but unless you can read/understand taiwan, we`re pretty much on our own :D
 
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mik

mik

allright tested the boost while driving. results:

~.6bar / 8.7psi vacuum
~.45bar / 6.5psi boost

pulley size on sc is 62mm
 

frank

Club Member
you should be able to work out the displacement of the s/c from those figures eh mik :)
if its reading .4 bar, the engine is being fed 1200cc x 1.4 i guess (with atmospheric pressure at 1 bar at sea level)
 

SplanK

Site Supporter
The R410 is quite a small blower, designed to go up to 1.4L engines with low boost levels. I don't think we are going to get epic performance out of the thing but defo has a bit of headroom.

If there is a 2.4:1 gear ratio, then at 6500rpm engine, that's 15600rpm supercharger.

Reading up about the TVS superchargers, I have read that the recommended max charger rpm is limited at 18000rpm because of the charger bearings, that's a 2.76:1 speed ratio. Above that I dare say you are going to start increasing the air temp as well as potential for fecking up the bearings/lobe crash into the housing. Although the performance map for the R410 seems to suggest 21000rpm is possible (which would sound awesome!)

Other than that, I get completely lost with the rest of it haha!
 
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mik

mik

today i was at the tuev for clearance testing my new wheel fitment. what they do is they jack the car up and then put two large blocks under the front left and rear right tire and let the car back down. it has to have clearance all the way down to pass the tests. theres plenty of space left in the arches! so im street legal with my tire setup :D after seeing how cool the lower car looks, i need coilovers haha :D

k13_010.jpg


k13_011.jpg
 
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mik

mik

cheers everyone :)

i thought about how to install a boost gauge, and maintain it simple and not destroying parts of my new car :D . we came up with the idea to put it into the center fan holes (like most 200sx and silvia owners do aswell)
the simplest way to include a gauge is to re-use the fan frame and to build a spacing ring that fits into it. to try it first i used the styrofoam which came with my gauge and cut a bit (ugly!) to fit it to the frame.
measurement of frame inner is 79mm. i think i will do the rings out of wood and cover the remaining front with maybe carbon fibre :)
i even think that the gauge has enough clearing so i dont have to cut anything from the honey mesh in the back of the fan frame. next thing is to find a hole from the engine bay to the passenger room :D

k13_012.JPG


k13_013.JPG


k13_014.JPG
 

solarice

Ex. Club Member
cheers everyone :)

i thought about how to install a boost gauge, and maintain it simple and not destroying parts of my new car :D . we came up with the idea to put it into the center fan holes (like most 200sx and silvia owners do aswell).

Looks like it'll look pretty neat once its all sorted.
 

squarepants

Ex. Club Member
Only just seen this! 1st modified k13 i have seen. i used to hate these.. but the more i look at them the more i like them, great work mik :)

i might have to consider one of these as my next car when they come down in price :D
 
I rather like them too. not so sure about the facelift, trying far too hard now, which is a shame.

af589f19-be93-4fb3-a4b5-562258d30279hires.jpg

I think I actually prefer the facelift...although it is a little kia picanto-esque :oops:

Thanks for posting this, by the way.
I've been looking out for an image of it since my local paper did a little column saying about the K13 facelift...and used a picture....of the rear quarter *facepalm* <_<
 

Kamarley

If it aint Jap its Crap!
today i was at the tuev for clearance testing my new wheel fitment. what they do is they jack the car up and then put two large blocks under the front left and rear right tire and let the car back down. it has to have clearance all the way down to pass the tests. theres plenty of space left in the arches! so im street legal with my tire setup :D after seeing how cool the lower car looks, i need coilovers haha :D

k13_010.jpg


k13_011.jpg
Wish I could have these on my k11 where did you get them??
 
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mik

mik

hehe squarepants, i didnt like them either until i saw some modified ones on the thai page :D
yes the new facelift is too, well i dont know what it is, but its far too many.
@kamarley: ive ordered them through my local shop (here in germany) but i think you can order them through their homepage: http://www.emotion-wheels.de/index.php?id=24&L=1

the cars status:
did about 3200miles in about two months, car is running great.
still didn't start the boost gauge fitting
still looking for an exhaust system
and i think i want to have coilovers :)
 

Seb_

Give me some frogs.
Site Supporter
Too much silver on the facelift front logo. I asked Nissan france and they replied its not an option and it can't be removed :(
 

Seb_

Give me some frogs.
Site Supporter
hehe squarepants, i didnt like them either until i saw some modified ones on the thai page :D
yes the new facelift is too, well i dont know what it is, but its far too many.
@kamarley: ive ordered them through my local shop (here in germany) but i think you can order them through their homepage: http://www.emotion-wheels.de/index.php?id=24&L=1

the cars status:
did about 3200miles in about two months, car is running great.
still didn't start the boost gauge fitting
still looking for an exhaust system
and i think i want to have coilovers :)

Mik: http://www.emotion-wheels.de/index.php?id=48&no_cache=1&L=1&tx_edgallery_pi1[pid]=149 :eek:
 
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mik

mik

Too much silver on the facelift front logo. I asked Nissan france and they replied its not an option and it can't be removed :(

well i think with help of plastidip, car wrapping or similar items such items can be made to look a bit better in my opinion :) everything is with an amount of passion and love to detail possible.
 
very nice. its decided im going for one of these and going 4wd sr20vet for the new project.
any chance of under chassis pics???
wanna see how much work il have cut out for me :)
 
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mik

mik

hey yes i wrote in your other post. ill try to do some under shots. but theres not mich to see as its packed with plastics and stuff :)
 
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mik

mik

here some progress on the gauge installment. the white piece is a prototype i will use a carbonpanel or a black plastic. in the second picture is a 52mm gauge, i think it looks much better with a 60mm gauge.

k13_015.jpg


k13_016.jpg
 
Nice. Can you tell me if those vents normally supply unheated air to your face when the heater is on warm? the K11 does that, and it's a feature very sadly missing from new cars these days.
 
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mik

mik

Nice. Can you tell me if those vents normally supply unheated air to your face when the heater is on warm? the K11 does that, and it's a feature very sadly missing from new cars these days.

it seems that it doesnt in my k13. but its so hot right now, that i cant be shure :D

haha that iphone wallpaper is awesome. thanks buddy :)
 
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mik

mik

Ok, today i finally got all the parts and the time to fit my boost gauge.

i used this nice fuse adapter with a cable (didnt knew that those are around, a friend gave me one) pretty cool, so i didn't have to cut the original wires/loom.

k13_017.jpg


fitted it in the lower fuse box.
k13_018.jpg


this is how i connected my gauge to the sensor. i had to cut the right tubing, to fit the valve what was fitted before the T-Piece.
k13_019.jpg


And this is the result: a 60mm AutoGauge Stepper Boost Gauge fitted into the Blowerhole.
k13_020.jpg
 
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