I need 400BHP.....
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I need 400BHP.....
So then.... now i have decided the spec'C' is staying in the garage im in need of a few new mods... the main being 400bhp....
What are my main needs???? An engine re-build to be safe??? turbo etc???
What are my main needs???? An engine re-build to be safe??? turbo etc???
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Originally Posted by RMA26
18 or 20G turbo, remap, ported headers, Decat
I think Powerstation do some twin scroll turbos capable of 400bhp.
Personally I am greedy, if doing a turbo swop I want 420-450bhp but then you are into more lag blah blah which I don't want.
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one word: drivability..!
If it's a daily driver then chasing figures is not the way to go. As said, big bhp= big turbo= more lag= less drivability..
IMHO (genuine) 350 ish with good response makes for a quicker road car than 400+ with poor response.
If it's a daily driver then chasing figures is not the way to go. As said, big bhp= big turbo= more lag= less drivability..
IMHO (genuine) 350 ish with good response makes for a quicker road car than 400+ with poor response.
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#8
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maybe try a custom made hybrid, i believe scoobyclinic delveloped one for there sc450 engines, might be an option to look at a custom roller bearing turbo to keep spool up times quick
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Originally Posted by jasonius
one word: drivability..!
If it's a daily driver then chasing figures is not the way to go. As said, big bhp= big turbo= more lag= less drivability..
IMHO (genuine) 350 ish with good response makes for a quicker road car than 400+ with poor response.
If it's a daily driver then chasing figures is not the way to go. As said, big bhp= big turbo= more lag= less drivability..
IMHO (genuine) 350 ish with good response makes for a quicker road car than 400+ with poor response.
Didnt think 400 would make much difference as its already 350 fairly easily...
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Originally Posted by Spec'c'57
mmmm So all i really need now is a new turbo and some ported headers??? or could i just get a turbo capable of 450ish...
the headers on your car are stainless steel equal length so there is no need to port them, i also think its hard to find a better set in the aftermarket ones ??? you really just need injectors, hybrid twin scroll and maybe a good fmic and filter plus the dreaded remap
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Originally Posted by stevebt
the headers on your car are stainless steel equal length so there is no need to port them, i also think its hard to find a better set in the aftermarket ones ??? you really just need injectors, hybrid twin scroll and maybe a good fmic and filter plus the dreaded remap
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Originally Posted by stevebt
you really just need injectors, hybrid twin scroll and maybe a good fmic and filter plus the dreaded remap
what hybrid TS blower makes a comfortable and genuine 400bhp?
Spec C, the turbo is your real concern here, the exhaust housing is limited to about where you are at present and to make a genuine 400bhp you'd also need larger injectors and ideally an adjustable fuel pressure regulator for better atomisation of said fuel - I see no need for a front mounted intercooler unless ofcourse you're looking at extended track use.
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Originally Posted by Mocom Racing
Steve,
what hybrid TS blower makes a comfortable and genuine 400bhp?
Spec C, the turbo is your real concern here, the exhaust housing is limited to about where you are at present and to make a genuine 400bhp you'd also need larger injectors and ideally an adjustable fuel pressure regulator for better atomisation of said fuel - I see no need for a front mounted intercooler unless ofcourse you're looking at extended track use.
what hybrid TS blower makes a comfortable and genuine 400bhp?
Spec C, the turbo is your real concern here, the exhaust housing is limited to about where you are at present and to make a genuine 400bhp you'd also need larger injectors and ideally an adjustable fuel pressure regulator for better atomisation of said fuel - I see no need for a front mounted intercooler unless ofcourse you're looking at extended track use.
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Originally Posted by Spec'c'57
so then which turbo.....
Youre limit is 360 with what you have
You need to either go single scroll TD06 20g (49lb compressor wheel) or bigger or wait for someone to get off their *** and manufacture uprated twin scrolls
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Originally Posted by Spec'c'57
so then which turbo.....
When talking to Iain Litchfield when he was developing the T25 it really is a trial and error process with turbos and the proof of the 'pudding' is trying it on the car rather than going by turbo manufacturers ratings as they always seem to be a very 'rough' guide.
APS have brought out an interesting rotated twin scroll but I would not fancy being a guinea pig for it See thread below;
https://www.scoobynet.com/drivetrain...in-scroll.html
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Zak's right. Trying to get anywhere near a reliable, "genuine" 400bhp out of the twin scroll turbo is just unrealistic, as the TS exhaust housing just can't take the flow, or the heat, and starts cracking.
Currently, the best solution is to convert to a single scroll, but to retain a twin up pipe to the turbo.
Edited because I thought I was on 22B.com (it's late !), and Shaun would have killed me for talking about a product
Mark.
Currently, the best solution is to convert to a single scroll, but to retain a twin up pipe to the turbo.
Edited because I thought I was on 22B.com (it's late !), and Shaun would have killed me for talking about a product
Mark.
Last edited by R19KET; 20 October 2006 at 12:39 AM.
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Litchfield and Powerstation are about the only two suppliers who can provide anything off the shelf quickly.
You could get something along the same lines as Shaun, or even try one of the units designed for the first T25's.
The ideal solution would be a GT30 garrett centre in a bigger exhaust housing, but as Mark has stated, everything is a compromise and you would gain a little lag.
Stevebt had his unit modified, using a Spec C core if you wanted to PM him, but again I think the hot side was the limiting factor. He has now gone for a Garrett.
I have gone a different way to Shaun, by trying to eke as much as I can out of the VF37 standard unit, using ancilliary parts. Im very happy with the results and lack of lag, but there will be no more to come, until a bigger turbo.
Im staying with what I have for now as its so nice to drive and the power is always there (also I currently have 3 bathrooms to pay refurbing on ), but I may look again in the new year.
You could get something along the same lines as Shaun, or even try one of the units designed for the first T25's.
The ideal solution would be a GT30 garrett centre in a bigger exhaust housing, but as Mark has stated, everything is a compromise and you would gain a little lag.
Stevebt had his unit modified, using a Spec C core if you wanted to PM him, but again I think the hot side was the limiting factor. He has now gone for a Garrett.
I have gone a different way to Shaun, by trying to eke as much as I can out of the VF37 standard unit, using ancilliary parts. Im very happy with the results and lack of lag, but there will be no more to come, until a bigger turbo.
Im staying with what I have for now as its so nice to drive and the power is always there (also I currently have 3 bathrooms to pay refurbing on ), but I may look again in the new year.
#21
What injector size does the Spec C have std. I thought 550? in which case 400bhp would be achievable.
Should need around 560cc's fuel flow per injector for 400bhp, so at say 4 bar fuel pressure 550's should flow closer to 630cc's. enough for a bit of leeway I'd say.
Std intercooler would do as well. Just need a turbo up to the job
Dave
Should need around 560cc's fuel flow per injector for 400bhp, so at say 4 bar fuel pressure 550's should flow closer to 630cc's. enough for a bit of leeway I'd say.
Std intercooler would do as well. Just need a turbo up to the job
Dave
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My car ran out of 'duty' on the STI injectors at around 370Bhp. The STI top mount started to struggle with the heat from the standard turbo at that BHP. But the main limiting factor found was the injectors.
We got a bit more by adding water injection, which makes the car richer at the same time, but not by a huge amount.
I now have 650's fitted, which I would recommend for anyone looking for more than 380.
Remember, that is standard VF and not some hybrid! (20g/GT30 etc), as the extra flow will bring power on its own.
We got a bit more by adding water injection, which makes the car richer at the same time, but not by a huge amount.
I now have 650's fitted, which I would recommend for anyone looking for more than 380.
Remember, that is standard VF and not some hybrid! (20g/GT30 etc), as the extra flow will bring power on its own.
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Originally Posted by David_Wallis
Sometimes a pic is worth a 1000 words, easier than explaining..
Lateral twinscroll/Garrett kit.
Lateral twinscroll/Garrett kit.
Do you know has this been tested and how does it compare to a comparable single scroll.
Looking at the pipe the gases are meeting each other just before it then goes into the turbo. Could that not mean even less efficiency than the single scroll set up as the gases have caused turbulence. On the single scroll the gases meet as soon as they come out of the headers so have chance to be less turbulent by the time it gets to the turbo.
IYSWIM.
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I would just like to point out that I didn't design the kit, but I am stocking it.
With regard to the turbo's, there just isn't a suitable alternative twin scroll housing currently available.
I have heard of some people offering bigger twin scroll options, but the only Garrett twin scroll housings of a suitable size are from diesel turbo's, and these housings have been tried, and tested for similar applications, and crack over time, due to the heat generated from a petrol engine.
Whether it be this, or another single scroll conversion kit, currently I think it's the only way forward for 400bhp +
Mark.
With regard to the turbo's, there just isn't a suitable alternative twin scroll housing currently available.
I have heard of some people offering bigger twin scroll options, but the only Garrett twin scroll housings of a suitable size are from diesel turbo's, and these housings have been tried, and tested for similar applications, and crack over time, due to the heat generated from a petrol engine.
Whether it be this, or another single scroll conversion kit, currently I think it's the only way forward for 400bhp +
Mark.
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Thanks for reply Mark.
I never realised a diesel turbo exhaust housing was made of a different material mix to a petrol version turbo housing. Well, they say you learn something every day.
I never realised a diesel turbo exhaust housing was made of a different material mix to a petrol version turbo housing. Well, they say you learn something every day.
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The twin pipes have been kept long to keep the gas speed high, and the transition to single pipe has been kept a smooth as possible.
There are several inches of straight pipe/turbo intake to smooth flow before the exhaust wheel.
It's hard to exactly compare the twin scroll conversion set up, to a single scroll set up "like for like", because the IHI, and Garrett GT series exhaust housings are not identical in size, or flow, but it would appear that the twin to single scroll conversion is faster spooling.
There will be more testing of different turbo spec's, but the cores will be based around the MD321H, & T series bolt on turbo's, which cover 400-450bhp.
Mark.
There are several inches of straight pipe/turbo intake to smooth flow before the exhaust wheel.
It's hard to exactly compare the twin scroll conversion set up, to a single scroll set up "like for like", because the IHI, and Garrett GT series exhaust housings are not identical in size, or flow, but it would appear that the twin to single scroll conversion is faster spooling.
There will be more testing of different turbo spec's, but the cores will be based around the MD321H, & T series bolt on turbo's, which cover 400-450bhp.
Mark.
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Originally Posted by Spec'c'57
So my best option is to revert to a single scroll for 400ish+ish
think im getting there....
think im getting there....