Stu @ M Developments

iTrader: (12)

No.. capacity is largely irrelevant with horsepower, as long as the turbo can shift teh air that the horsepower requires for the volumetric efficiency of teh engine in question.

Extra capacity was just helpfull to move the damn turbine with any speed in the first place

CozzyBrom

i know that stu i mean over reving the turbo
2lt cozzy boost drops off 7600 max (boost tailed off from 36 psi)
so surly a bigger engine will require more air hence boost dropping off earlyer
i weld things so dont go into dynamics of turbos

Stu @ M Developments

iTrader: (12)

Not really Brom, again, horsepower is largely a function of airmoving ability against RPM.

If your reving to 9k to make your power, and theres a lot of power, your gonna need a big turbo.

Dont forget the T4 is really a 400bhp turbo if i recall (Got the compressor map somewhere) so expecting over 500 was always a fooking stretch anyway...

hexxon

Quite correct that. As well as the maximum volume of air which the turbo is able to compress per second is what sets the limit of the maximal output of power in the engine(that is, the size of the inlet of the compressor part, in a basical stage). Just as well is the exhaust side of the head and manifold (combined with a huge amount of other parameters, such as volumetric efficiency at different revs), what sets the limit of maximum exhaust flow in the engine. These two factors are the most fundamental parts when picking a suitable turbocharger for an engine, theres a few others as well but these are far more tricky...

Disabled Account

I did'nt know that Mike............I dont drink (alchohol) or smoke either

Do spend about 98% of what I earn on cars/petrol though

=========================================

hexxon

Well, were three of us then... Though i spend more than i have on my beuty...

CozzyBrom

ok mate no worrys
i will stick to welding and designing things for cozys

hexxon

Well you are doing that VERY well from what ive seen...

CozzyBrom

so whats the happy meduim then with these gt turbos
if you run a gt35 small turbine housing you get low down boost 3000 rpm 1 1/2 bar but it will surge its nuts off till 5000 rpm wont make large boost 2.6 bar
go for a gt 35/40
large exhaust housing small wheel you get no boost till 4200 but then it peeks 2.6 bar at 4400
how can you have best of both worlds ?
thanx for your input

CozzyBrom

thanx

Kev.H

question : This F1 Turbo the Jenspeed\Blue WRC car has why is it so special who is it made by ?? Surely turbo Technology has moved on since F1 cars had turbo's and how much would it cost ??

ta

hexxon

Theres a plethora of nice turbines and exhaust housings for these. First of all, you need to select a compressor housing which will be able to produce air for the wanted power output, as well as compressor to suit the rev. Then theres a question of selecting the exhaust-parts, turbine and housing, suitable for playing with your given exhaust pressures nicely through the whole rev-range. All rotating parts should be as light as possible and bearings should produce as little friction as possible. After this has been done, you should look for options of bettering the spool-up even more, if its interesting. Such things would be porting.

Doing all this in an appropriate way gives a nice setup...

hexxon

Dont know anything about this turbo-specification to be honest. Strange that they call them F1-turbos, as these wouldnt be much fitting for a Cosworth YB in original shape. Made for cars revving higher than any Cosworth YB known to me. Turbo technology is so much better today comparing 20 years back. Though, when new, these were state of the art. A state of the art turbo today is the same Ł as a nice car from in here... If not even more... Dont know anything about the Jenspeed turbo as said, but would suspect that KRB Trading is involved.

Stu @ M Developments

iTrader: (12)

To elaborate very lightly on this, you also need to match the turbine speed against turbine housing and engine airflow with any given RPM as if you spin it to fast too soon, you will end up with "Surge" by trying to force the engine to consume air it simply isnt ready to consume and you end up in a "No Flow " situation

CozzyBrom

thanx mate
am kind of happy with mine as it is it come on full boost at 4400 and goes to 9000 i am also told it will take 200 shot of noz with out over reving aswell
i dont no that yet as i havent used the noz yet
thanx for your input nice to have a techy that answers questons

Stu @ M Developments

iTrader: (12)

Ive got a great essay on surge somewhere

hexxon

Yes, exactly, this is where the exhaust pressure comes into play... It shouldnt be to high at any revs, considering the turbine trim as well of course, since this will force unwanted air into the engine.

hexxon

Hey, send me that one! peknd01@student.vxu.se

CozzyBrom

end up in a "No Flow " situation
and a shatterd wheel

Stu @ M Developments

iTrader: (12)

The way this conversation is going i may just paste it into here if anyones interested? I guess its still about flow so its not "off-topic"

Stavros

IMHO the "F1 Turbo" on the Blue WRC is just a Turbonetics T-Series...

The F1 bit is just talk/hype/bullshit.

Ive seen a LOT of F1/Indycar turbos (theres a storeroom full of em at Bluesprint) and they NOTHING like that, and TBH like Patrik said, a turbo suited to F1/Indy spec wouldnt be at all suited to that engine.

And it looks remarkably like a Turbonetics turbo

the white RS500 also seen that saying F1 turbo in the spec, but i cant see from the pics what it is, wouldnt be suprised if its a Holset or summat...

Kev.H

That would make sense as Julian Godfrey and Pat Dorans Rs200's run Turbonectics if i recall maybe he\they prefer them ??

Mike Rainbird

iTrader: (3)

Brom,
I would not push any of my turbos beyond 32psi. To do so gets you into all sorts of trouble with overspeeding / higher inlet temps etc.

My old RS500 engine used to hold 32psi to the limiter (8k) and my current engine with it's higher than usual (T4 type) compression ratio is limited to a held 27psi all the way to the limiter (7.8k).

I will stick within the normal limits of the standard valve gear with new engine, as I don't see the point in making a laggy beast. I have got so use to the T3/4 type response my current engine has, I would be loathe to get rid of it.

I want to drive Lee's car to see if the response he has is better than a T4 to see if I go GT30 or GT35. If the GT35 has similar (or better) response than a T4, then I'll go for that (and run less boost to achieve the power I want) or if not, go to the GT30, which I know makes 530bhp @ 26psi... .

Jallu

RANJ

i thought the norweigan one runs a turbonetics t66 with 1.06 housing

Disabled Account

Mike,

Is the GT30 a good upgrade from a T4?
.....the 26 PSI bit sounds like a good move

I take it it'ss not a "drop in" replacement? I.E. external w/gate version only?

Kev.H

what the hell is that

CozzyBrom

ohh look the good old audi wastegate i ran one of those on me saff last yr
nice piece of kit can change valves in them and alsorts

Jallu

It's a escort cossie from Finland

Mike Rainbird

iTrader: (3)

Doug,
This is the conversion I priced for you, so no it is not a drop-in by your definition (i.e. cheap ).

Jallu

Probaply the best wastegate that you can find from eighties stock-car...

Kev.H

anymore pics

Stu @ M Developments

iTrader: (12)

One of the most impressive thing in that bay for me is this boost hose security solution



Welcome to PF as well.

Can everyone please keep the piccys a little smaller please? ta

Disabled Account

Mike, I thought that you priced up for a GT35 Or is the difference in price (to GT30 cost) small in relation to the whole conversion price anyway?

Stavros

Doug- Some companies can do you an internal wastegate GT30 which is a drop in job, but IMHO its a bit like skimming pistons or using a spacer plate to lower compression

Bodge

Jallu

Sorry for the pic-sizes, I'm a newbie

Here's another escort's engine bay from finland, not cossie though... I left the pics behind links...

1995
http://www.tvracing.net/images/Konehuone.jpg
2002
http://www.tvracing.net/images/viikki2.jpg
http://www.tvracing.net/images/Koneh...kokoamista.jpg
2004
http://www.tvracing.net/images/Konehuone%20.jpg
Plenum
http://www.tvracing.net/images/imusarja%20koottuna.jpg
http://www.tvracing.net/images/imuarja.jpg
http://www.tvracing.net/images/IMG%202imusarja.jpg

Disabled Account

Point taken Steve

I guess at this level of BHP (500 +) an external wastgate is the only proper way to do the job

Mike Rainbird

iTrader: (3)

Doug,
No price difference AFAIK .

CozzyBrom

cool pics i see they move engines back alot over in your country
cool idea isnt it


i moved mine 10 inch back to give better weight split

Kev.H

Brom your engine bay looks so cool