Turbo sizing and boost threshold?!?!
 

Hey everyone. I have a ported FC with a Garrett T04s 1.15 hotside/ TA51 .55 compressor. Fully built. Haltech maps tuned by XS (whom you all seem to love, and not to burst anyones bubble, but I sent my maps to both Haltech and the HITman for a looksee and they both said it is crap... Not to mention I always thought the 9 mpg thing was a bit excessive) The car is a dog below 4000 rpm, starts making good boost around 5000 and by redline is making 400+ rwhp @ 15psi. I don't care HOW much the peak HP is it is still only pulling 14 flat because of the lag!!! (yes I know how to launch) Not to mention around a road circuit (where I prefer to be) I've got nothing out of the turns.

What is your turbo size and boost threshhold? I am considering swapping to a TO4e. From what I understand FC blocks are only reliable to about 400-450hp (does porting change that?) however I dont care about HP as much as I want an 11 or 12 second car. ZO6 killer. ;) Any recommendations on the a/r ratios and wheel trim on a tangental T04e for me?

Thanks! ~Jeremy

P.S. I see a lot of you use the T04s on your FD's and are doing VERY well, what makes the differrence? Is it because the 13B-REW can handle higher boost and HP?

Hi Jeremy. I have had problems with XS also, well not me but a few of my customers. I work at a rotory performance shop in Sac,CA. You are running a bit rich from what it sounds maybe alot rich. If you want some advice call me at 916-852-0306.

Red Line Chris

a TA51 compressor wheel is a big sucker isn't it? like T72 sized thing or close to it?

you need a smaller compressor side, a 60-1 with a 0.70a/r compressor housing. also what trim is your exhuast wheel? that may also have a lot to do with it.

My exhaust wheel is a P trim. Yes the compressor is HUGE!!! :)

FD's have higher compression than your 87-88 TII.

GT42, boost threshold at 4000 then it hits like a train.

My motor is a 90... Does it not have the same rotors as the FD?

your turbo set up is a set up for 25+psi, its not a turbo set up to haul arse on a circut, its a drag turbo. due to the size of your compressor, you have increased lag, you'd be better off with a 60-1 type front on it

Why would someone (XS) size that turbo to a car that was only planning on running 15-18 psi???