I was wondering, lets say you have a 360 bhp sti with a twinscroll turbo and a 360 bhp sti with a normal turbo would the one with the twinscroll be any quicker?
The twinscoll spools up quicker so shouldnt this car come out on top?
The twinscoll spools up quicker so shouldnt this car come out on top?
Scooby Regular
Correct. Assuming everything else was equal (and it never is) - both cars were set up and mapped optimally etc, the twin scroll car would be quicker in practice simply by dint of spooling up much earlier and having better throttle response. You'd spend less time waiting for it to get onto boost.
Scooby Regular
id love to go donw the route of twin scroll on my classic just not sure if it possilbe and also whats the biggest twin scrol is out there and what sort of bhp can it push
Circa 500bhp for a standard position, twin entry unit is possible nowadays.
Scooby Regular
I am sure you can convert the classic, you will need sump, up pipe, headers and the turbo. Think that's it. Twin scroll is awsome or drop a gear on a single scroll and put your foot down simples.
Scooby Regular
Twin scroll isn't all its cracked up to be otherwise I wouldn't of pulled mine off and put a single scroll turbo on 

Scooby Regular
Quote:
Steve, we all know its because they didnt make one that BIG for all that power your running Originally Posted by stevebt
Twin scroll isn't all its cracked up to be otherwise I wouldn't of pulled mine off and put a single scroll turbo on
or else you probably would have one
(plus it was in its infancy back then, now it seems to be coming on quite nicely
)Tony

Steve,
Twinscroll can be all that it is cracked up to be..... it's dependant on your application and requirements. I suspect you realise what type of turbo Andy Forrest was running in his drag car don't you.
Twinscroll can be all that it is cracked up to be..... it's dependant on your application and requirements. I suspect you realise what type of turbo Andy Forrest was running in his drag car don't you.

Scooby Regular
the only reason im thinking it is becuase i dont want to see my car past the 390 it is at now which is good i just think a 390 bhp powered bya twinscroll would be even more fun but im going to have one of harvey up pipes done soon for my rcm headers and 20g and that should bring it on boost a bit quicker and a touch less lag not that i dont agree with the droping a gear lol
Orange Club
FWIW, my take on this is that a twinscroll is fantastic on sub-400bhp cars: the spool characteristic and minimal lag are phenomenol.
For 420+, most twinscrolls, as I understand it, are twin entry rather twinscroll so you don't actually get the advantage of a genuine twinscroll, although the exhaust manifold design is less of a compromise on a scoob so retaining the twinscroll manifold layout is advantageous.
You can probably get better value performance (i.e. better bhp-per-£) by switching (or sticking) to single scroll and using one of the many tried and tested single scroll turbos (MD555, MD321T etc) and, if your car is already twinscroll, a twin-to-single up-pipe from someone like Tracktive and a new downpipe.
IMHO of course
For 420+, most twinscrolls, as I understand it, are twin entry rather twinscroll so you don't actually get the advantage of a genuine twinscroll, although the exhaust manifold design is less of a compromise on a scoob so retaining the twinscroll manifold layout is advantageous.
You can probably get better value performance (i.e. better bhp-per-£) by switching (or sticking) to single scroll and using one of the many tried and tested single scroll turbos (MD555, MD321T etc) and, if your car is already twinscroll, a twin-to-single up-pipe from someone like Tracktive and a new downpipe.
IMHO of course


