micra maxi

[TURBOHIGGINS]

just noticed on the top left of this page a photo of my car driven by Glen Campbell,
have it now up for sale , with a rebuild ,have lots of pics and spec available.
good lookin site by the way

 

[SuperUno]

Got a link to the spec / pics ?

 

[TURBOHIGGINS]

Check it out here: http://www.pistonheads.com/classifi.../micra-maxi-1300-lhd/1443629?utm_source=share

See if that works . Only 3 pics there 150 bhp

 

[Craig]

Nice, more pics please

 

[Low Rider]

'Similar' spec to ours build wise. Shame to see it up for sale so soon after it was snapped up on eBay, (the car has a fair bit of history).

Would be interested to see a dyno print out to see the power delivery.

 

[TURBOHIGGINS]

The sale fell through on eBay . Didn't make enough
I don't have any print outs on the car ,
I've known it for 5 yrs .
It had done 153 bhp and 117 torque
Now in storage until someone wants it .

 

[Low Rider]

Ah I see, hopefull dotty will see light of day again and find a good owner

It's rare to find anyone with a dyno plot, especially if it's a Peter Vaughan engine.

We've started trom scratch on the engine as there appeared to be no spec to go by.

 

[Tony Perks]

what spec cams were in it Higgins, I am building a customers engine now but he has only got 773 cams and I have my doubts about them producing the power from such short durations?

 

[frank]

what spec cams were in it Higgins, I am building a customers engine now but he has only got 773 cams and I have my doubts about them producing the power from such short durations?

nismo 304 deg were,nt they ?

 

[Tony Perks]

Thanks frank that confirms my suspicions, the 773's are only 264, not really rally cams!!, and only (from memory) 52 deg overlap.

 

[frank]

Thanks frank that confirms my suspicions, the 773's are only 264, not really rally cams!!, and only (from memory) 52 deg overlap.

more a "fast road cam" eh tony, autosprint did me some (285 iirc) that were very peaky

 

[Low Rider]

what spec cams were in it Higgins, I am building a customers engine now but he has only got 773 cams and I have my doubts about them producing the power from such short durations?

They will produce power but it greatly depends on the spec of the engine and what your customer is wanting to achieve. If he's looking for that magic 150bhp number then it will end in dissapointment. On individual throttles you'll be around the 100bhp/l area, more if you build in additional compression.

Thanks frank that confirms my suspicions, the 773's are only 264, not really rally cams!!, and only (from memory) 52 deg overlap.

Yup, 264deg, 52 overlap and a tad over 9mm lift, which puts them at a very nice fast road cam with good behaviour.

nismo 304 deg were,nt they ?

Don't suppose you have any deets on those profiles Frank, they were both down at 304deg IIRC?

 

[frank]

Don't suppose you have any deets on those profiles Frank?

fraid not, i think they were figures that you posted up dave (155hp @ 8132, 15kg @ 7165, running keihins)

 

[Low Rider]

fraid not, i think they were figures that you posted up dave (155hp @ 8132, 15kg @ 7165, running keihins)

Errr, grey matter fail on my part then

I'll note those. I am trying to get a hold of a dyno printout of a CG13 making around 150bhp to see what it looks like. Absolutely nothing to go by from anyone making 150bhp.

If I can get hold of the dyno plot, I'll post it up in this thread.

 

[Tony Perks]

the engine that was in the car made 123bhp, on what look like std cams, but i have not and am not stripping it to find out, the new engine will be on throttle bodies fully ported head 11.5:1 CR forged pistons etc, its a rally car so will need good power and torque. Just as an example on the same rollers a week earlyer we had a Class 4 Autograss micra that makes 93 Bhp at 7.5 ish with 1300 cams cleaned up head and bike carbs, I quite fancy putting some BD3 profiles in 296 deg duration just short of 9mm lift 2mm ish at tdc timed at 106Deg and 84 deg Overlap.
The customer supplied the cams so if it wont make good power then I will put in a proper set!-Darren

 

[Tony Perks]

Frank do you still have those cams if so wanna part with them?, i do have a set of 270 pipers here that Matt H sent me to evaluate lift etc, I could do a deal on them?

 

[frank]

Frank do you still have those cams if so wanna part with them?, i do have a set of 270 pipers here that Matt H sent me to evaluate lift etc, I could do a deal on them?

that one was recut to 260/10mm i,m afraid mate, i dont bother with cams anymore tbh (boosting is far easier ), they worked well but i was getting increased wear on the 5th journal on the pipers and autosprints (the tail-end bearing)
running the 2 shims under the buckets, and experimenting with re-profiled bucket faces to cut down on the side forces would,ve been my next step

 

[Low Rider]

the engine that was in the car made 123bhp, on what look like std cams, but i have not and am not stripping it to find out, the new engine will be on throttle bodies fully ported head 11.5:1 CR forged pistons etc, its a rally car so will need good power and torque. Just as an example on the same rollers a week earlyer we had a Class 4 Autograss micra that makes 93 Bhp at 7.5 ish with 1300 cams cleaned up head and bike carbs, I quite fancy putting some BD3 profiles in 296 deg duration just short of 9mm lift 2mm ish at tdc timed at 106Deg and 84 deg Overlap.
The customer supplied the cams so if it wont make good power then I will put in a proper set!-Darren

123bhp sounds optimistic but I will stay away from potential dyno fights, as we've had a fair few on here in the past lol. As long as you stick with the same dyno you will see what the %'age gains are

BD3 profiles sound like an interesting choice. At that lift you'll just be able to get that out of a standard cast blank but I would consider the limits of the lifter. Although the CG uses a 30mm follower, it's 28mm if you stick with a biscuit shim, which puts a limitation on what you can get away with profile wise.

 

[Low Rider]

that one was recut to 260/10mm i,m afraid mate, i dont bother with cams anymore tbh (boosting is far easier ), they worked well but i was getting increased wear on the 5th journal on the pipers and autosprints (the tail-end bearing)
running the 2 shims under the buckets, and experimenting with re-profiled bucket faces to cut down on the side forces would,ve been my next step

Do you reckon that may have been influenced by the cam profile, reduced base circle or maybe the ground down buckets Frank? It would certainly be interesting to see what the surface profiles are on a set of de-lipped bucket tops.

We spent a lot of time 'umming and aaring' over cam profiles to avoid unwanted loading with a 30mm follower limit.

 

[Tony Perks]

The 123bhp is on 40 webbers works spec manifold and system, and 3 D Ignition with emerald 6 series ECU But yes i feel a little high, car drives like it has a genuine 100 at the wheels though.

 

[Low Rider]

The 123bhp is on 40 webbers works spec manifold and system, and 3 D Ignition with emerald 6 series ECU But yes i feel a little high, car drives like it has a genuine 100 at the wheels though.

Pretty close to the 123bhp we made at 7250rpm Stock long block, 773's and individual throttles. We do however use a dyno which is notorious for reading lower than the average.

Good to know, as there aren't much in the way of power figures available, particularly above 100bhp/l N/A, as many do not go that far.

 

[Tony Perks]

Pretty close to the 123bhp we made at 7250rpm Stock long block, 773's and individual throttles. We do however use a dyno which is notorious for reading lower than the average.

Good to know, as there aren't much in the way of power figures available, particularly above 100bhp/l N/A, as many do not go that far.

I will get the print out tomorrow as i'm working there again, who's car was the 123 engine on?

 

[Tony Perks]

It will be interesting to see what my 1054 makes when finished, same spec head as Darrens, probably BD3 cams, Darrens webbers decent exhaust etc.

 

[frank]

Do you reckon that may have been influenced by the cam profile, reduced base circle or maybe the ground down buckets Frank? It would certainly be interesting to see what the surface profiles are on a set of de-lipped bucket tops.

We spent a lot of time 'umming and aaring' over cam profiles to avoid unwanted loading with a 30mm follower limit.

i think its just that the lobes are kicking the cam against the bearing caps dave (because they are side-swiping the bucket faces instead of pushing down on the middle area (like the less aggressive stock cams do) and i think bigger base circles would make it worse if anything.
its mainly on that far end bearing, the other bearings share the loadings in the different directions eh
we,ve trolled higgins,s thread somewhat (but its not in the for sale section anyway )

 

[Low Rider]

Yeah, well we let that one slide

That's interesting. I'm interested as the lifter is supposed to have a large radius on the top face, (effectively a very large mushroom). I was wondering what face is there when the biscuit shim is removed and the lip ground away. Coupled with a smaller base circle, which could lead to more flex, may contribute to journal wear. Can't see the base circle having too huge an impact as it's not as radical as some I've seen.

Sticking with a good base circle is just to help keep things rigid and opting for a full width lifter helps to stop unwanted loads with big high lift cams. Trouble with the K11 is there's nothing much to be done with the lifter size. I guess we'll see how things go in the long run...

 

[frank]

the shims are flat-ground surely mate ? and yes i had a parabolic shape in mind for the bucket tops
the 260/10 cams were very noisy/aggressive so i guess you have to expect a higher wear rate, that pic is the piper cam btw

 

[Low Rider]

That may be the case yes.

 

[frank]

it might smooth out the acceleration loads on the valve action eh (less violently smacking them open/shut)
the pipers and autosprint cams had roughly the same contact to contact duration angles as stock, but the stock cams initial opening ramps are very gentle
https://www.highpowermedia.com/blog/3056/the-domed-tappet

 

[Tony Perks]

I managed to print out the report from last week of Darren's Maxi, will post it tomorrow i am too tired to wrestle the scanner now!

 

[Tony Perks]

As promised here is the scanned Graph, sorry its a bit pale but it was yellow on white! Click to enlarge please.

 

[Low Rider]

As a comparison, here's a stock long block, 773 cams, individual throttles and group A system.

Click to be enlarge also

 

[Tony Perks]

Worked out why the car felt so slow considering the power out put, the chokes in the carbs (Webber 40's) had been bored to nearly 36mm, there was absolutely no radius on the venturi !