274 race cams HELP PLEASE!

[pulsarboby]

hiya chaps need some help and advise please: im currently rebuilding my engine ready to race next year (curcuit) ive got a set of 274 piper cams, will these be a straight fit? i was told that there about as lairy as you can run without making any changes to springs, shims etc, just wondered if anyone has them fitted or equivelant who knows if anything has to be altered in order to run them?:?

 

[Mr GTiR]

I have 272 Piper cams in mine with 11.5mm of life and i'm still running on standard valve and springs. The only thing i would suggest is get some rocker stoppers off Ashills.

Also, make sure your head has been fully ported and gas flowed to get the most out of your cams.

 

[stumo]

Also, make sure your head has been fully ported and gas flowed to get the most out of your cams.

8)

 

[pulsarboby]

where abouts is ashills and any idea what they cost? was gonna get it ported and flowed anyway so that solves that. also what is the point of fitting a 1.2 or 2mm head gasket as this surely lowers compression ratio and makes for a slower car. generally if you have head skimmed faster car, dont understand that! how much are these thicker head gaskets and wheres best place to get one from? im in essex cheers chaps

 

[CruiseGTi-R]

Hiteq have gaskets.

lower compression is a little safer for higher boost levels. depends what you're intending to run boost at, piston spec etc.

circuit racing eh - good lad.

 

[Odin]

also what is the point of fitting a 1.2 or 2mm head gasket as this surely lowers compression ratio and makes for a slower car. generally if you have head skimmed faster car, dont understand that! how much are these thicker head gaskets and wheres best place to get one from? im in essex cheers chaps

The standard gasket is supposed to be about 1.4mm so the 1.2 mm metal gasket would be an improvment over standard, I wouldn't bother with the 2mm one as the car will probably be rubbish off boost :roll: :der: ....

rob

 

[pulsarboby]

dont want to run more than 1.4 max will probably be 1.2 will have forge pistons 700cc injectors and emanage with fuel set to match. completely rebuilding car with basically every engine mod imaginable as well as fast flow manifold and all the normal stuff. costing me a packet. will post some piccies for you guys when finished, should be done sometime in october, ready to go on track.
was told by a tuner not to run car at more than 1bar boost on curcuit as bigger boost= less reliability=more time stuck under bonnet for me=longer pockets with very short arms, and a monster brainache lol

 

[pulsarboby]

i thought standard gasket was 1.2 rob? when i said dont want to run more than 1.4 i meant boost (sounds like i meant gasket thickness)

 

[Odin]

was told by a tuner not to run car at more than 1bar boost on curcuit as bigger boost= less reliability=more time stuck under bonnet for me=longer pockets with very short arms, and a monster brainache lol

What a load of bollox :yawn: :roll: , Maybe if you had a standard engine then yes maybe 1 bar would be a wise move, But with a rebuilt engine using all the right stuff then their's no reason you shouldn't run what ever you need to get your best times, I recon 1.6 bar - 1.8 bar with the right turbo would be fine ;-) .......

As long as you do plenty of good quality oil changes when it's being used for track outings then I can't see a problem, Any engine being used on the track all the time will have a shorter life span than a road car would, But it would just be a case of fitting new bearings and rings every 25-30k....




Rob

 

[Odin]

i thought standard gasket was 1.2 rob? when i said dont want to run more than 1.4 i meant boost (sounds like i meant gasket thickness)

I've never seen the spec of a standard gasket fella, But I've heard from 1.2mm- 1.4mm, the most common answer has been 1.4mm so I'm sticking with that as my answer :lol: :lol: :lol: :lol: .

And 1.4 bar would be fine fella if not a bit of a waste on a rebuilt engine, Seeing as I'm on 1.5bar and 400 bhp on a 66k standard engine .


Rob

 

[pulsarboby]

cheers for info only thing pretty much standard will be turbo with 360 thrust untill ive got dosh to uprate that. so you think i could run 1.6 without too many probs?

 

[Rishi]

where abouts is ashills and any idea what they cost? was gonna get it ported and flowed anyway so that solves that. also what is the point of fitting a 1.2 or 2mm head gasket as this surely lowers compression ratio and makes for a slower car. generally if you have head skimmed faster car, dont understand that! how much are these thicker head gaskets and wheres best place to get one from? im in essex cheers chaps

You need a head gasket whether it be a 0.8mm, 1mm, 1.2mm or 2mm head gasket but you do actually need a gasket there!... :roll:

What exactly are you doing to your engine...? You seem to be relying on your tuners info regarding engine specs an awful lot... 1bar on a rebuilt engine and standard turbo.. Seems a complete waste to me... Well not for the tuners pockets anyway..



Rishi

 

[Fast Guy]

also what is the point of fitting a 1.2 or 2mm head gasket as this surely lowers compression ratio and makes for a slower car. generally if you have head skimmed faster car, dont understand that!

Yes if you skim the head on a head with a combustion chamber you'll increase the compression ratio and so the power output of the engine. (some heads are completely flat with the combustion chamber being the space above the piston in the block, so skimming the head won't increase the CR.)


The old school of thought on a turbo car was that you need to run a lower compression ration in order to run more boost and so more power before you run into detonation problems.

The more modern was of doing it (in some cases) is to raise the compression ratio and run more boost and run a stand alone ecu that can control the ignition timing to avoid det problems for longer.

 

[azboy]

the standard 1.4 mm head gasket after copressing is the same as the 1.2 steel 1 as steel ones dont compress as much when torqued down.

 

[pulsarboby]

right, i can see what you guys are saying but in a nutshell car will be doing 20 lap races at a time, twice a day over 2 days a week throughout a season and its an awfull lot of stress on engine! the tuner said that it is better and more reliable to run at a lower boost and go for reliability rather than a fast burst of speed as you would on a drag strip, and i can see his point! the car will be quick enough to deal with most things on track i would have thought running 1.2 of boost over a sustained period of time. (i wont know for sure untill ive done some test days) but thats the general ideaproblem with the gtir is as you all know is that there pigs to work on, and if it goes bang one day its a whole weekend of racing ruined and a whole lot of heartache trying to get it fixed for following weekends event, thats why he suggested running at a safe boost level! think me stubby pinkys got cramp now through all this writing, lol

 

[Fast Guy]

For reliability you need to keep your charge temps as low as possible and water and oil temps as close to normal. So a large intercooler and maybe even a chargecooler/water injection as well as an uprated radiator and oil cooler.
Your turbo selection could go along way towards these temps. ie a low lag high boost will probably be running abit hotter than a bigger turbo running lower boost to get the same power.

PS Ashills is a member on here so you can just pm him.

 

[pulsarboby]

cheers fella, thanks for your help. got big fmic, still need to sort out rad should anyone on here have one for sale aftermarket and modded of course!