fro people who want big power and stay british

Empty Pockets

New Member
Don't get me wrong Ed, i'm not trying to enlighten you on turbo's, what i'm saying is you can't compare this to a holset, let alone anything else. We both know the benefits of bb turbo's. going twinscroll is only a custom designed manifold and a divided exhaust housing lol, both of which cost no more if buying new, my protech manifold would have cost the same if i had not chose a split pulse design, same with the turbo, it costs nothing more to choose what housing you want when you order. If top end power was my goal i would have gone with a equal length, standard firing order manifold and a large single exhaust housing turbo. There are pro's and con's to both methods, if a quick spool up and reasonable power is your goal then its a very valid route to take on a four pot.
 
Don't get me wrong Ed, i'm not trying to enlighten you on turbo's, what i'm saying is you can't compare this to a holset, let alone anything else. We both know the benefits of bb turbo's. going twinscroll is only a custom designed manifold and a divided exhaust housing lol, both of which cost no more if buying new, my protech manifold would have cost the same if i had not chose a split pulse design, same with the turbo, it costs nothing more to choose what housing you want when you order. If top end power was my goal i would have gone with a equal length, standard firing order manifold and a large single exhaust housing turbo. There are pro's and con's to both methods, if a quick spool up and reasonable power is your goal then its a very valid route to take on a four pot.
Totally agree with you mate, as said on the modifiers it depends what you want from the car :thumbsup:. I would love to see some evidence for how much benefit you get from twin vs single entry using the same tubo/engine, but I don't think anyone here has the £3k+ it would cost in manifolds and turbos. I think with a twin scroll set up you'd have to tune the engine to get the most out of it, like run more overlap on the cam.

I'd also like to see what components the GS racing one uses from a Holset turbo, but that is definatley one of our turbine housings, I can see the 7 digit part number cast in it and it would seem more hassle than its worth to change the core items. So the only thing I can see different is the comp cover. Like I said I see no benefit in changing the comp cover. Its not as if we don't have enough variants of the bl**dy things, why they could find one that suited. As I said I would also be interested to see if they had done the same level of safety testing we carry out.

Excuse the corporate BS, but heres a vid of some testing we did of cheap chinese knock-offs (skip through to 3:20):
http://www.youtube.com/watch?v=Za0DieZHMKc
Not sure I'd want that happening in my engine bay
 
Last edited:

ashills

Active Member
on the gt35 setup a few of the evo boys go up to he T4 flange setup with twin scroll so it doesnt suffer surge or to much restriction with the divived flange
 

Empty Pockets

New Member
Yeah, there's not alot of choice for the divided housing from garrett, .78 in t3 and .106 in t4, I chose the t3 but with the anti-surge cover as i'm more bothered by spool up than peak power, i hope i made the right choice as it will be fun if we have to swap flanges on the manifold
 

Empty Pockets

New Member
If he's got 3k spare lol. Shame we couldn't get cheap roller/mapping time, and someone with an equal length protech mani and a similar size single entry turbo to test with, i would offer my car for the testing.
 
Top