big kris

Hey everyone, I'm looking to find out some information about twinscroll turbo's. What is the difference between a twinscroll and a regular turbo such as a TD05? What is the advantage/disadvantages associated with the twinscrolls? Finally, if I was to fit a twinscroll to my 95 type RA would I need to change the exhaust manifolds or anything else to suit?

Cheers

Kris

martin800

i think that i have read that changing to a twin scroll is quite an involved job, need to change alot of things including the sump! might be wrong, but fairly sure.

TonyBurns

iTrader: (3)

No disadvantages though its not worth doing on your car as you need to change most of the engine.
Differences are that instead of the gasses coming in in one go, they come in on 2 different flows, slightly offset so one comes in earlier and one later, this means that when you change gear, instead of the gasses running out you have a constant flow for that bit extra, which keeps the turbo spooled up (less lag on changes).
A TD05 would be classed as a single scroll turbo v a vf36 for example which is a twin scroll.
Have a search on google etc, you should find something on there

Tony

frayz

iTrader: (7)

A JDM twinscroll sti will make 1 bar of boost approx 900rpm earlier than that of the single scroll UK cars.

Much improved response and spool time makes for a much nicer to drive and useable car on the road.

pippyrips

correct

Damocell

iTrader: (1)

I think you need to change the:

Manifold
Sump
Up-pipe
Turbo
down pipe.

Don't think I have forgotten anything else

Jap performance parts do all the above minus the sump for £1000 I think

Damo

big kris

Cool thanks for all the info guys! Im planning what I'm after with the new engine I'm building up, so trying to weigh up the pro's and con's of each setup. So TS setup is best for response, less spool up time and less lag in between gear changes, but is it as good top end as a single scroll turbo? I found a description of a TS on the AFS website which gave a great description of the technical differences, so I'm clear on that

Where would I find the correct sump to use for the TS setup?

Kris