Alan_D

What sort of power could you have an engine from say a sapph Cosworth running at on standard internals before it would be classed as unsafe?

andrewg

prob rpms that make it weak point

550 is prob average

Alan_D

Cheers. Didn't think it would be as much as that!

andrewg

there will be tuners that will prob run over 600 on standard internals

Chip

iTrader: (3)

Are you referring to standard unmachined standard compression pistons as well andrewg?
And what about the head? Surely you dont mean standard there?

TurboShed

I am VERY interested in any discussion about how much power and how, can be got out of standard compression. When I had my engine rebuilt, I regretted staying with standard compression, because I thought I was limited to 400bhp. Am I wrong?

Staffi

iTrader: (1)

550-600 Andrew?? i always assumed it was way below that, more around 400-450 max, shows what i know

Staffi

iTrader: (1)

Surely the Block too would be struggling at the above power levels?? well 205 anyway

Alan_D

I was meaning totally standard engine in every way. Only bolt on mods etc and mapping to increase the power.

Chip

iTrader: (3)

Do you want it driveable or just a big peak figure, cause I have a turbo for sale that would definately see you over 500bhp on a totally standard engine, but it probably wouldnt be doing much below 6-7Krpm, then just a quick squirt of big power upto the limiter at say 8K and when you changed gear it would be off boost again and shit, but would get you a big figure.

In terms of good driveable power, on standard cams etc still, I would say low 400s on a GT3071 is the best power you will get whilst still being nice to drive.

Alan_D

Yes, I'd want it do be driveable as opposed to making a peak figure. I don't actually have a Cosworth, I was just curious, although I'm looking at building a track day car soon and a Cosworth is one of the possibilities.

The other is building a classic shape Impreza with the Newage running gear, and they are something I'm fairly familiar with, hence asking this question on here.

andrewg

when he said limit i was thinkin about parts that need to be uprated before they break!

Alan_D

That is what I meant.

cozzie4d

I'd say a standard head won't go much further then 400 to 430bhp.
that would be the weakest link then

pete mcrash

iTrader: (1)

......cossierich did 450+ on a std head (with cam)....

cossie daz

you beat me to it

dave cos4x4

iTrader: (5)

mine did 430 on a standard engine.

pete mcrash

iTrader: (1)

.......then ya crashed it..................

TurboShed

You mean it wouldn't flow enough, or that something would break?

cozzie4d

I'd say play it "safe" and don't go over 400bhp

BRAMMER

iTrader: (23)

Chip i've been meaning to pm you regarding these turbo's - this is something i want to change over the winter so if you could pm me what the prices are and do you recommend internal or external gate??

Chip

iTrader: (3)

Agreed then, strength wise the crank and rods are well proven at 600bhp, and the standard pistons are physically strong enough for that even if most people prefer to lower the CR.

Chip

iTrader: (3)

Get the scooby mate, it will be a far better trackday car on a sensible budget.

Just look at the rear suspension setup on the two cars!

Alan_D

Well I already know that I could have a 400bhp Impreza which I could drive to and from trackdays/events, it would be that reliable when done right. So maybe it is the better option? The whole reason behind going for Newage running gear would be for strength/reliability, as the drivetrain is well known to be able to stand up to 500bhp, whereas the Classic drivetrain is the complete opposite: soft as shite!

Chip

iTrader: (3)

You could just use a complete newage car, far less hassle and they arent mega money anymore.

fuzzy

surely 400bhp will be reliable in any engine done right? its the done right part that most fail on.

Alan_D

Want a classic as they are a bit lighter.

pete mcrash

iTrader: (1)

....and a better looking car.........

col cos1

iTrader: (5)

i couldnt get more than 360ish@wheels out of standard head on greys

600bhp escos

std engine with just bolt ons...i wouldnt go over 400 bhp otherwise it will be problematic...a ported head at this level only allows for bhp for less boost...a bd 14 inlet can achieve 500ish with the right bits after 500 bhp i would always use proper forged pistons..mahles always go out of shape quick much over 500bhp...

600bhp escos

thats around 440 bhp so thats bloody good...my last 500 was running 4 greys the t4 and bd14 on std engine at 2 bar and made 426

pete mcrash

iTrader: (1)

......mine gets that at the mo.....and would probably do more (with bigger injectors, more boost).....how much more i dont know....

Glenn_

iTrader: (1)

Pete no way is yours 360 your saff is well fooking fast.

600bhp escos

360@wheels is around 440 at fly so would be fucking quick!!!

stevieturbo

Re Subaru.

Unless its a new model short motor ( ie STI8 or bove ), 400bhp on a SUbaru bottom end is a ticking time bomb especially with track use.
The conrods in the std engine are crap, although the later STI rods are much better. Pistons whether forged STI types or cast will handle 400bhp fine if tuned correctly.
If its a new model STI car you have with 6speed box etc...then with a couple of bolt on bits, you'll easily see a reliable 400bhp. Maybe even about 450bhp with the right turbo at say 1.6/1.7bar
One of Lateral's MD321T's would get you there, or for faster spool aim for the MD321H and slightly less power.
It'll go well, handle well, and have an almost unbreakable drivetrain.


Re Cossie.
They've a steel crank, steel rods, and good forged pistons. Head sealing aside....no reason why you couldnt ram a load of boost into one with a big lower.

I seen one in Malta just scraping 10s runs, totally standard engine ( with studs and head gasket ) with a T66 bolted to it running about 40psi lol ( along with other supporting bolt on mods of course )

Seemed to work fine for him.

Alan_D

Cheers. I already have a built 2.5 bottom end priced from Api. That would be more than capable.

Regarding the standard internals: Andy Forrest ran 440bhp on a 95 WRX years ago with standard internals. He used to drive to and from events. He will be doing all my mapping, and giving all advice should I go down the Subaru route again, so I am not concerned with that.

I would be interested in a Focus Cosworth conversion though. I have had a few road going Focus' now and think the handling is spot on, but what concerns me is how they will handle with rear or 4wd, as obviously they aren't designed for that?

stevieturbo

He may have done so...but it wasnt a customers car, and he wasnt concerned about breakages.

old rods on standard engines have failed at standard power with abusive drivers. It simply isnt worth the risk pushing them too hard, especially if its a track car. The std rods are crap.

"Handling" is an individual assessment.

A well built and designed car would go very fast in 4wd trim. Less so in 2wd obviously.

Alan_D

He ran it for 2 years at that power.

To be honest I'd be totally confident about running an Impreza engine on standard internals up to 400bhp if it was mapped by a top mapper. Plenty of Subaru engines have failed because they are played about with by amateurs! The standard rods might be crap(in your opinion), but I would think the failures you talk about would invlove some underlying cause. If not, then it's just bad luck. But I have used a UK Turbo engine at 270bhp(so over 50bhp more than standard) like a race engine for about 20000 miles and it didn't bat an eyelid.

stevieturbo

You just need to ask around.

Classic rods are crap that is fact, not just my opinion, and Ive seen them fail on totally standard cars, rod life has little to do with mapping. Its the same rods used on the EJ18, 20, 22 etc whether normally aspirated or turbocharged.

A friend also has a std UK 2.0 running about 350, and has some 160k miles on it now. So they can be reliable too...but it cant be gauranteed.

Alan_D

I don't need to ask around though, as I am 100% confident about having an Impreza mapped for more than standard power on standard internals. I have never even thought of the rods as being an issue, and Andy didn't mention that either strangely enough?? I take it you are familiar with what he does? He is a professional, probably one of the best, if not the best at what he does in Europe.

I think we'll have to agree to disagree on this one, as this thread has now gone totally off topic.