seppy

hey chaps and chapesses.

i have a 1994 wrx jap import. it's had a few mods done to it. however, does anybody know if i can safely add a second turbo. i'm considering having a smaller turbo for low revs to get an initial burst of speed up to lets say 4500rpm then hoping for a larger turbo to kick in at 4500rpm. i understand i may have to upgrade the intercooler and fuel injectors. was thinking of a water spray intercooler and gold or platinum plated injectors. also looking at uprating the filter system to increase the airflow. am i looking at upgrading the right parts to cope with the increase in power? what parts and turbos would be recommended?

thanks in advance for any suggestions

seppy

MrRA

The cost involved would be far too prohibitve in my opinion. A bespoke exhaust system is going to be needed along with bespoke piping for the intercooler etc etc. It would pose so many issues in terms of packaging as well that you're better off sticking with a proven single turbo steup. If you want quick spool and good strong power delivery then look at going to a twin scroll setup, but there are also fantastic single scroll turbos out there too.

Proby521

iTrader: (1)

As said, the money it would cost with the development of exhaust manifold pipework, inlet manifold design, fitting the whole lot under the bonnet, you'd be better off with twin scroll setup or proven single turbo.

seppy

thanks guys.. will take your words for it. not sure what a twin scroll is though.. how do i get the twin scroll??

Stealth

iTrader: (4)

cost a fortune to convert what you have, but if you really want a twin turbo just go and Buy a Legacy B4 RSK I think they are twin turbo'd

MrRA

A twin scroll turbo is turbo that has a divided exhaust housing. This separates the exhaust pulses more effectively from each cylinder. It makes the turbo more efficient at building boost. They spool very early. It's still not cheap to get a twin scroll setup though as you will need equal length exhaust headers, twin scroll up-pipe and downpipe, different sump, oil pickup and dipstick.

There are plenty of early spooling single scroll turbos out there that will fit straight onto your car without too much fuss. Go for simple and effective mods along with a good remap by someone good like Bob Rawle, Simon of Jolly Green Monster, Pat Herbourn to name but a few and your car will be transformed.

vindaloo

There are well trodden paths to getting more out of the early classics.
In no particular order.
1) Decat or sportscat exhaust downpipe. Decat centre section exhaust.
2) Induction mods: Resonator removal, panel or cone filter mods.
3) Now ECU (Apexi Power FC or maybe SIMTEK)

Doing the above as a package should spool the turbo very much earlier than it does at present.

Regarding twin turbos, unless you have money to burn and don't mind the car being off the road, forget it.

J.