T-uk

don't want to clutter pete's thread up.

are you guys doing the rolling road day that pete's organising?

I would really like to see the difference between your two cars. I am not interested in the peak figures but since your cars run similar/same? gearing it would be interesting to see the graphs with basically the same mods bar steve having the better heads/cams and higher rev limit.

sg72

Sorry T-UK.
Won't be able to make it.
I'm saving up to get engine oot.Rods and pistons fitted.the w/i set up. New injectors.Look at(fix) clutch gearbox interface and
New Boost map.

So maybe 2005 LOL!

Could send you my graph from last run?
Alan's already seen it.

Cheers Steve.

AlanG

Wasn't intending to John.
Don't see the car will have changed much by then, if anything.

Alan

T-uk

thanks for the graph steve.

I compared it to a 20g of jb's with standard headers and alan's 20g run.

as I though it shows that you have a larger useable rev range to play with,it must be the cams and heads.all the cars are doing similar torque at about 4500rpm(within 20lbf/ft) but your car hangs onto everything much longer, looks another 4-500rpm I think this is what impressed me most about your car. on the road your car revved past the peaks with enough left in the rev range to hold gears and make full use of it. the UK's seem to peak and get to the limiter all too quick.

IMO is has shown me that although UK's can be tuned to offer similar peaks the STI is the better drivers car.

now just need to blow mine up so I can drop an STI lump in with one of andy's 20g's ,just not sure which STI,2litre or 2.5

AlanG

I can't seem to find Steve's graph. Can you forward it again to me either Steve or John?

(Am looking at cams just now)

Alan

T-uk

yhm

AlanG

Cheers John
YHM2

Alan

Andy.F

Very similar specs, identical even ?
Are they the same person ? anyone ever seen them at the same time ?

AlanG

AlanG

Had a look at the graphs, cheers John.

I can't see the difference the Sti cams should give. The torque curves are very similar?

Alan

sg72

LOL! Andy.

I like to think. I don't even exist.

At least not in the respect of you's normal mortals.

Oh Dear. On the POP again!

BTW. Any opinion on getting the rods/pistons W/I and injectors to the fore.

I'm hoping after April.

Callum Ferguson

iTrader: (1)

Alan - apologies if you've already seen this but you might find it interesting. It certainly looks like you may be right about the STi cams. JUN looks but may be lumpy on idle or noisy?

NASIOC Cam Info

callum

Andy.F

I think it is more the rpm capability of the Sti cams, the UK rpm limit is 7000rpm as valve float is close behind due to the hydraulic lifters and soft springs.
The Sti will rev to 8k although shifting at 7500 is probably more appropriate. This makes the set up feel more flexible as you can 'short shift' at 7k or hold it a fair bit longer, this pays dividends on the street where they go and place corners in the most awkward places

Andy

AlanG

Cheers Callum
I hadn't seen it.

I made an excel sheet up after John's comments to try and see how much better the Sti cams/heads are over the UK's ( for the two similar specced cars) but couldn't see much of a difference in torque curves, so am now confused what to look for when speccing my new cams.

Can anyone give me the specs of Ver5 Uk cams and Ver5 Sti cams? (Might help clear up the confusion)


Alan

Andy.F

Steve, You want to get a set of heavy duty bearings too, maybe consider a set of cams ??

Andy

Andy.F

Alan, as far as I'm aware the 99/sti5 heads are identical regards valve/port sizes.
Regards the cams, the sti's can run approx 6 degrees more timing for the same spec/boost as a UK although would not appear to make any more power
I suspect the difference comes when you run a bigger turbo such as Harveys, then the cams allow improved breathing at higher rpm.
Are you doing rods pistons to allow higher rpm ?

[Edited by Andy.F - 12/31/2003 8:48:05 PM]

Callum Ferguson

iTrader: (1)

Andy,
Speaking hypothetically if cams were uprated to JUN 272's with Ti retainers + uprated springs where would it be sensible to set the rpm limit on a 2.5?

callum

sg72

Would it be fair to say that the STI cams are configured in such a way as to allow for this ignition advancement. Within the constaints of Boost/turbo and the fact that >100 octane fuel would be used.

This would cover how some cars are prone to detonation(Normally JDM STIs in this country)

This would become more prevailant with the change of one part of the set-up. Turbo/Air/fuel flow.

This should be able to be covered by a remap.

However it would certainly be asking something of the mapper to be able to cover the infinite number of possibilities that can occur due to the changes incurred in modification of a mechanical part.
and its effects on the rest of the system.
Yes it is simple for someone to analyse the data supplied and adjust to suit.
But this is only at the time of day/condition /temp that remap is done and cannot allow for even slight changes in any one of varying conditions.
This would be where all uk cars make 217bhp and later jdm STIs make 276bhp Because they should Anywhere/anytime.(Factory developed)
Once you modify anything mechanical Filter/exhaust/Turbo/cooling.
and get a remap the map is only for time conditional on time of mapping.
Would this explain why cars of similar spec on a rolling road same day can produce disimilar results .
Would depend on which day/conditions each was mapped

Was not looking for higher revs Andy but perhaps slightly more boost with a reversion back to more advanced timing.

2hrs to go will he make it?

Steve.

T-uk

quick reply because I am off out

both cars doing similar at 4500rpm.

torque and power cross over and UK peaks at 6400rpm, has 600rpm to hold gear and redlines at 7k. STI peaks at 6800rpm but has another 1200rpm to hold gear ***if*** needed.

as andy says this makes the STI feel more flexible.

Andy.F

Steve

With the Apexi PFC you retain the MAF meter therefore the air density is calculated. This compensates for different atmospheric pressure and temperature to a degree (excuse the pun) So your cars output will be more consistant than Alans for example as I'm not sure that the link has temperature and atmospheric pressure compensation.

Yes, the uprated internals will allow higher boost to be used safely (you could run more now.... live dangerously ) and an aftermarket turbo inlet pipe would free up some bhp too

Andy

Andy.F

Callum

I'm not sure re the rpm limit, you are using uprated pistons and rods IIRC ? Even with a big turbo and 272 cams I believe the 2.5's still make their maximum power before 7k.
My gut feel is that 7.5k would be a sensible/practical limit.

Andy

sg72

Darn! Forgot about that inlet pipe.

Didn't actually Know you could get A/M pipes

Thought they were home built

Gonna push Andy's Turbo to the MAX!

AlanG

Link doesn't have temp/atmo compensation.

sg72

Happy New Year!

Alan

Think we could meet this Weekend/somewhere?

Chat/Where the FAK. are we going?

Am off whenever. you/I can make it.

We are not the same person. Are we?

Steve.

Callum Ferguson

iTrader: (1)

Happy New Year to All & here's hoping for lots more scooby/evo power in Scotland during 2004. Good luck with all your projects.

Andy, thanks for the reply & yes pistons are being done as soon as Omega get themselves organised, the rods are ready.

A 7500 limit would be great and if it can be made to hold power to close on 7k then it will be fine. The idea is to have a broad power band but I would much prefer 2 - 6 than 4 - 8

cheers,
callum

harvey

iTrader: (48)

Happy New Year everybody. Very interesting thread and some interesting engines on the way North of the border.

T-uk

happy new year all

callum,

I have a suspicion that when john banks fits the 6 speed, he will be following your lead, with changing pistons and rods to raise the rpm's. I do not think he is going to like the first 4 short gears as much as he used to, with a 7k limit.

Callum Ferguson

iTrader: (1)

Hi John,

It will make a change for anyone to be following my lead - I'm hardly the trendsetting type..LOL

I've never liked the 6-speed. IMHO it's only asset is that it appears to be reasonably strong. In standard form, with a narrow power band & short ratio's the car was fussy. It's all very well having a six speed box for pose value but the car could not be driven quickly in a lazy way IYKWIM. More torque has undoubtedly helped the situation but it may change again if the car has lots of torque and runs through the rev range too quickly I'm inclined to think that a very strong five speed would be more effective above 400bhp. Where to get such a beast without paying £35K to Prodrive could be a problem

cheers,
callum

AlanG

Sounds like it's the valvetrain within the heads that allows the greater RPM range rather than rods/pistons John.

Unless JB has blown yet another "i'm not going any further myth...."

Alan

Andy.F

Alan

JB has Sti5 heads/cams/springs and solid lifters, this is just fine to 8000rpm

It's the std 2.5 rods/pistons that warrant the 7000rpm limit.

On the 2.0 UK it's the cams/springs/lifters/pistons and rods that dictate the rpm limit !!

Andy