IAN RS2k

iTrader: (2)

I have a 3dr Cosworth that I have been running a GT28 Hybrid turbo on it was built for a S14 drift car it was a .64 AR turbine & a GT35 compressor wheel. My engine has ported head, AB07 cams Motec ecu wasted spark etc. It made 350bhp the turbo was rated 400bhp for the S14, the engine did not rev at the top end but on track it was like a rocket out the corners leaving most cars standing. I really liked this as I don't like laggy cars that when the power does come in it over powers the rear tyres I am more into handling than just straight line power. I am now looking for a new turbo as I want it to rev cleaner so I can hold gears longer plus the GT28 was a bit aggressive it came in hard & fast. I want to get a new turbo that spools up really quick & around 400 bhp 420 max so the quickest spool turbo to give the best bottom end power, my exhaust manifold is a small turbo Escort 4x4 manifold with the studs moved in to suit the T25 flange so I am looking at the Borg Warner EFR 6258 rated 225- 450 hp does anybody have any experience with this turbo?

smiley

Loads of info here mark ahead on that threads your man on these

https://passionford.com/forum/genera...fr-turbos.html

IAN RS2k

iTrader: (2)

Cheers that was a good review of EFRs I did not read that one before when I searched but like most posts on turbos they tend to end up talking 500bhp. The 6258 is the smallest one which is single scroll I need to find out if these are as good as I was not sure if its the twin scroll ones that are a lot better but not the single scroll ones.
It was interesting about what was faster at the same horse power but like mine it was faster quicker so I was way ahead the time we both are at full power this meant on track I out performed cars with a lot more horse power

smiley

I would give mark a shout mate he's very helpful and more qualified to give you the answer you need Ian I only know what's been written about the twin on their fast spooling from low down making a very responsive engine also no big aggressive kick in the back once on full boost sounds ideal for you

Caddyshack

Yes, speak to Mark Shead, he did my one on 7064 and it is night and day better than my T34 that I had, it just spools up as soon as you touch the throttle.

Listen to Mark and go with what he says. I suspect you could use the bigger one and have more power later.

jontysafe

The 7163 turbo sounds just about perfect for your application.

Twin scroll on the smaller frame size and flows the numbers to retain power up top as well.

It's what I'm using on a new build.

Jay,

iTrader: (4)

Is that a t3 flange mate

jontysafe

No! It's T25, T4 or v band

Only twin scroll as far as I know on the T4 housing though

Mark Shead

50% of the gain is the turbo the other 50% is the correct manifold design with the gains when using a EFR.

Mark