Twin scroll for 450-500bhp?
 

New 2.5l build ready, should pick it up in a few days. Will be running-in and getting a few 1000 miles on it using the stock VF37 complete with standard twinscroll headers etc.

I have a ceramic coated Milltek twinscroll decat downpipe already fitted and a set of coated Tomei twin scroll headers and uppipe waiting to go on.

Original plan was to use the new Litchfield twinscroll turbo, but this is beginning to sound like vapourware :( Originally due at the beginning of this year, reading between the lines when I spoke with Iain last, it could well be autumn before it's ready...and I could see that becoming longer if the first production units don't work as expected etc.

So, in case it doesn't materialise, any ideas of what other twin-scroll options there might be? I've been wearing my keyboard out Googling and searching and can't really come up with anything, so any pointers would be welcomed. Looking for 450bhp, 500 tops, and bags of torque :D

I know I could go single scroll, but that means I will have to sell on the twinscroll parts I have, and that seems a shame - and I really want to keep the twinscroll setup if at all possible :D

Iain's turbo WILL get released.

If you can not wait, then you could always go down the single scroll route. I have come from twin scroll, so I know about the pro's and con's. I have an AET GT30 Hybrid (standard position) and it produces the best spool, lowdown grunt and top end power, whilst still on VPower that I know of (for standard fit). Easy 500bhp. I hit 1bar at circa 2700rpm, 2bar by 3k.

All you need is a twin to single scroll up-pipe and a single scroll downpipe.

If you are disappointed I will eat my hat. :D

OK, thanks Shaun. I guess I'm just being impatient - car's been off the road for 2 months; a further delay a week ago as the new twin plate clutch's grabbing, and no sign of the new turbo the engine was built for :(

As it happens, I know of a second hand miltek single scroll downpipe going...so would not be that expensive to go to single scroll at this stage. Any suggestions for good twin-to-single uppipes?

Hmmm...wait for Iain or convert. Aargh..choices choices :lol1:

Tracktive Solutions for the twin to single scroll pipe. :)

:thumb:

Where has yours hit 2 bar by 3k Shaun or are you quoting my spool up figures on the V ?

Oh and you ought to mention the £3.5K's worth of cossie heads and cams that are fitted to yours to help :D

Guess those'll help :lol:

Got standard '05 Spec C heads on mine, modified for the 2.5l.

Which exact model GT30 have you got Shaun? Dyno plots?

Duncan,
On the road in 5th / 6th. Realistically though it is circa 3100, albeit with the higher compression ratio. It was somewhere between 3200-3300 before.

Tim,
Spec C heads are good and I suspect that if I was doing it all over again, I would of stuck with those. The Cossie heads come in to their own, when you start going GT35>.

Not sure of the exact model. Speak to Andy Taylor of AET Turbo's (AET-TURBOS.CO.UK are the recognised specialists in turbos, turbochargers, design, build and repair of all turbo and custom turbos, rebuilt turbos, dyno tuning, a) and tell him you want to know details about Shaun's GT30 standard fit turbo..... he will know what you are on about.

Dyno plots are all over ScoobyNet and 22b. Look at my project thread in the ScoobyNet Projects Forum . :) https://www.scoobynet.com/projects-4...oject-car.html

Have you got many hats to eat :D Me and you both have ditched the twin scroll as we both know its a loosing bet for that power ;)

Steve,
Based on certain people getting a bit twitchy about the release and potential of these new twin scroll housings, that may not be the case moving forward.

I am totally open minded and look forward to seeing these new twin scrolls. :)

Wait for Iain...:thumb: I am...

Just weighing up my options at the moment.

Contacted Andy Taylor at AET - the turbo Shaun uses is a GT3076R-based unit using a bespoke housing and they describe it as a 500+bhp unit. They also have a lesser unit good for 475+bhp that's a little cheaper. Also have a price on a twin-to-single scroll up-pipe, so I now have a "fallback" plan :)

The car will not be run-in or ready for the turbo upgrade for a month or two yet, so I won't be rushing into a decision. I'll take stock in late August and see what progress there is on the Litchfield unit.

Go for the 500bhp unit :-)

I have tested both and would say the same as above. :) The larger turbo produced 485bhp at the fly on VPower and with only 1.45bar boost, albeit with my higher compression 2.5. It produced 485bhp at the HUBS at 1.8bar. :)