Single Turbo Choice: Street and AutoX Car
 

I've been trying to make a decision on a turbo setup for some time now. I was originally going to go with BNR twins, but I've committed now to a single turbo setup (read: sold all of my stock twins stuff).

My first impulse was to jump on the GT35R bandwagon. After driving a 400whp GT35R FD, I changed my mind. The car was not for me at all. I beat my own time around an autoX course in that FD by 2 seconds with a stock S4 N/A.

I want something like what can be had from the Apexi RX-6 turbo setup, but hopefully without the price tag. Namely, full boost by 3k RPM, 350whp @ 12-15lbs of boost.

After a conversation I had today, my options seem to be the following:

GT3076R 53trim w/ .82 a/r turbine
OR
T3/T04E 60trim w/ .82 a/r turbine

Opinions?

This is relevant to my interests. To you have a preference on wastegate? I've heard that the 3076 will run out of breath on the top end and that 350 is about the most you'll get out of it. i'd at least go with the bigger turbine section.

just hearsay though.

I'm going to try out the Synapse Engineering wastegate, we'll see how that goes.

I've heard the same thing about the 3076 not having the top end, but I'd rather sacrifice 50whp on the top end for full boost at 2800-3000 rpm.

Which brings me to the T04E. How much difference does the whole ball bearing thing make? It's half the price, has more 'breath', but I don't know what the spool is like? I don't know anyone who has one.

Get the GT35R with the .82 AR turbine. You most like drove what I have, GT35R 1.06 AR.

I have driven a lot of single turbo fds, I always hear claims of people saying x turbo hits x amount of boost by 3-3500rpm and it never seems true. If you are shooting for 350rwhp and want great response just go with the stock twins or BNRs in sequential mode. Use the PFC to adjust the transition point of the secondary to make it more controlled and you will have the fastest spooling setup period.

This is just my opinion obviously, take it for what it is worth. If you want autox performance stay with the twins.

+1

The twins will do 350whp no problem and it is much cheaper and easier than going single.

If you definitely want to install a single turbo then look at the GT35R with the .82 turbine housing. I'm almost positive the FD you drove had a larger housing (more lag).

Really - dyno torque plots are going to tell you more than boost numbers will.

I have built an FD with the 35R .82 Housing - and it made boost fairly quick - but felt laggy compared to my GT3071R in the RX8; but I make over 200 lb/ft of torque at 3000 RPM...

I think comparing some torque graphs would help you pick the right snail for your car.

I'll have to ask what the a/r was on the car I drove. It could have had the 1.06. But still, what is the upside to going with the 35R?

David, I am going to take a look at going with the BNR's again, but it will be more money to do so than the 3076.

Anyways, thank you everyone for your responses and input.

I could see a 3076 being a really good street turbo.

It really shouldnt be any more money. You dont need a custom downpipe, it already has the wastegate, you dont need a custom manifold, custom oil feed/drain lines. They are hard to beat for simplicity/performance/price.

Like I mentioned before, I sold/gave away all of my twins stuff to other local FD owners already, after my last set of twins ate itself at 15lbs. The initial purchase price plus all of the components to make a reliable, functioning sequential system will be significantly more, and it will be more complicated.

$2600 for everything I need, fab up a downpipe, bolt on and attach a couple of vacuum hoses. Oil lines are minor, I probably have enough stuff just lying around here to finish those off.

I think I'm pretty set on the 3076. I'll post up some pictures ect. in the spring when it's done.

I'm sorta in your boat too. I originally went with a T-78 single to during my rebuild swap, to simplify the process and I got the kit for a good price. I tried my first auto-x and now I'm considering something smaller, I'd like to find something that has an external W/G since I want to try and reuse some what I can like my GReddy manifold and type-R W/G after reading what you are considering I'm going to start looking into those myself. Best of luck to you =)

For AutoX/street I am with David... stick with the Sequential Twins. I haven't bought and sold and many FD's as David, but I have quite a few pass through my hands. There is no better set up for AutoX/Street IMO then Sequential Twins... whether it be stock, BNR Stage 3's, or 99spec. I currently have 3 FD's... a sequential, a T78 Single, and a full nonsequential car. I'd rather drive the sequential any day and time on the street or autoX. Track Days though... T78 all the way :D

I been thinking about this for awhile... And to be honest.. I'm a fan of twins and fan of BNR turbos.

My blk FD will have BNR stage 3s in seq. and my MB has stock twins in seq.. I also have a BIG T-76BB that's been sitting in my living room.. Newly rebuilt.. with all the junk to put in minus the DP. But I just can't seem to put that in there as I like No lag :)

Throw that baby in there, nothing a 75 shot of nitrous couldnt spool up :)

Phil, you need to build the black car into a 600+rwhp fd or bust.