matt your right you would need well into 20s to get that on a t4 with mods to portin ect

 

I reckon you could make 400 on about 1.2 bar with high enough comp. ratio. Would it be reliable,i doubt it. Would it run like that on pump fuel, i doubt that too

 

if an engine was running 350bhp from 17psi on a T34.63, would that have the potential to run 450bhp on more boost?

 

comp ratio doesnt effect how powerful an engine is

 

Wont you make more power lb for lb on a high(er) comp motor?

 

dont think so mate..
comp ratio changes cylinder pressure makin git less stressful at given boost pressure than it would be on higer comp.

higher comp gives better response but not more power

 

I always thought there was 2 ways of making power......Low comp,big boost which normally seem power made low(er) down or high comp,less boost and rev the tits of it which normally makes power high(er) than the first way.
I'm far from being an expert on the subject though

 

revs increase power but again comp ratio has nothing to do with an engines ability to rev

 

Not ability to rev but dont low comp motors tend to make power lower down?
Btw whats the comp ratio on your motor? Or is that top secret?

 

so what's the advanatge of sean running this comp engine?

https://passionford.com/forum/viewtopic.php?t=232580

 

T34 with a 63 housing might scrape 400 horses with a good set up, anything beyond that I reckon you would need a T4. So am told

 

what about a T38

 

This might sound like a silly question but can you simply bolt a T4 onto an escort cossie and expect to gain mega bhp?
I'm not mechanically minded nor liked minded for that matter so don't know? but i was offered one recently at a good price and turned it down.

 

comp ratio on my car will be lower than probably any other on here and it makes peak powr at 8k which agan is probably higher than most on here, work that one out

 

you would get an increase in bhp if you set the boost as a higher level..

the standard engine prob wouldnt last too long tho.

 

No, you'd need a remap and bigger injectors at the very least. With more engine work on top, you'd get more power.

 

Thanks mate. That's good to know! I'll keep the T4 option open again in the coming months after I get other mods sorted out first.

 

A guy was selling one on ebay for under Ł200 new. It does seem a good deal to me however it wasn't a Garret.

 

why does everybody ignore me

 

thats alot of help
yeah ive noticed you dont see many making figures like yours,max hp at 8k sounds pretty nice.
No worries about me half inching your spec.....i'm not building a cossie motor either just very interested as to why yours is making power where it is. Also interested in the lack of vacuum and cam spec but i doubt very much your gonna give anything away.
Yours being lower comp than most would make sense in terms of safety for extended periods of time at 100% throttle,what kinda egt's are you seeing?

PM me if you dont want it splashed across the boards

 

will be some dodgy truck turbo then..

thats why its only 200 quid...

is useless really

 

peak power is where is where it is beacuse of a few reasons, cam timing is certainly one of them.

i would need to drive a high comp cossie to see what the benifits are on the road before i could comment fully on the difference between mine.

the EGTs and back pressure have been measured on the latest sesion on the rollers when geting it ready for the dady thrash.
EGTs are within acceptable limits thats all i can say

as for my spec..some people know it, some think they know it

 

Thanks
Quality motor btw

 

cheers mate

have spent too much time and cash on the engine now just to give away all the secrets

 

Yeah it would be kinda foolish to the extreme to whip out a Garrett only to replace it with a Ł200 T4 turbo.

 

ive just got 403bhp on 28psi with a t34.63

 

Surely comp ratio does drastically affect power output, just as it does on N/A engines?

Running more boost on a low comp would be the same as running less on a high comp, all to do with how much mixture gets compressed and burnt?

although im probably wrong thought id ad my bit

 

i run a TT T38 with high comp , 449,4 BHP at 8k and holds 28psi


PeterLucas Posted: Sun Nov 26, 2006 9:06 pm Post subject:

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Surely comp ratio does drastically affect power output, just as it does on N/A engines?

Running more boost on a low comp would be the same as running less on a high comp, all to do with how much mixture gets compressed and burnt?

although im probably wrong thought id ad my bit


your not far off there, i run high comp and T38 as i want big power, but as its a road car i dont want the 5 day lag of a T4 lol

 

not all T4's are laggy

 

t35 34psi 427bhp

 

higher comp will give more power per boost pressure, but NOT much, esp as timing will prob need to be retarded more, and overall can run less, so car will prob have less power overall on pump fuel, hence the REASON people go low comp.

improves off boost power, but not hugely, not when it only 1point higher or whatever.

dont really affect lag or boost threshold.

dont know why seans doing it, prob for reasons that he will regret as its not all what the hype suggests.

engine advantages rollers, or nitrous?

 

No because flowing 450 would be more than the compressor can manage.

 

PS

If you want to know the basics about understanding compressors, try this topic:

http://www.vauxhallsportforum.com/ph...urbos-t92.html