Turbo'ing my Carrera

[JMA-RUF]

Hi all,

I've decided to jump on the band wagon and do a turbo conversion on my Carrera, so I'm planning to start collecting bits and pieces over the next few months.

First question:

What turbo do you turbo GODs recommend for ~400 crank HP and offers excellent spool-up?

I like my heat, so I might go with a set of GHL's or B&B's (still undecided).

Advice please???

P.S: I've considered the K27 turbo's, but they seem to be over-priced and I prefer to go with a Garrett or Turbonetics solution.

[gtu935]

If you click onto the turbonetics web site they have a graph that wil help you determine the type and size of turbo to use

[JMA-RUF]

I looked into that and it recommended a T60-1, P-Trim, 0.68 A/R hot housing. Would that be a good solution for ~10psi boost? I plan to run 930 headers, so I'm limited to a T3 turbine housing it seems. Unless I have the headers butchered and replace the T3 flange with a T4 flange? Advice?

[WydRyd]

I vote for a Garrett GT30R and it gives you head-room to grow in HP later on

[JMA-RUF]

Hmmm... GT30R looks interesting.

What A/R is best for my 3.2L?

Any input appreciated.

[mb911]

we use turbonetics T4/TO4E 's with .69 a/r and 57 trim.. all 3 of us using them love them and if you call turbonetics they confirm its the best fit for the application

[JMA-RUF]

Thanks Ben. So your turbo has a T4 turbine housing? You aren't running a normal aftermarket 930 header? They all seem to have T3 flanges on them for some reason.

Please keep the recommendations coming.

[gtu935]

You can order it from Turbonetics with the T-3 hot side

[JMA-RUF]

Yes, but isn't a T3 housing too restrictive for our motors?

Please enlighten me

[gtu935]

Not if you size it correctly.

[gtu935]

Check out the graph on the Turbonetices web site

http://www.turboneticsinc.com/turbomatrix.htm

[JMA-RUF]

OK, I just did and it recommends a T60-1 Fullsize, STG V, 0.68 A/R.

What the heck is a STG V? Is that some sort of T3 housing/turbine?

It says this turbo will support up to 450HP, which leaves me a little head room I guess

[mb911]

call them they will set you up properly.. and yes I use a t4 hot side as this is what was suggested for future upgrades if I wanted it..

http://forums.pelicanparts.com/uploads9/bens+0051170163934.jpg[/img]

here is what I am running for headers

[JMA-RUF]

Thanks Ben... Very nice and neat setup. How does it perform on the road? Those runners look quite long.

[beepbeep]

I would recomend Garrett GT30R for that output. Excellent spool-up and power/spoolup ratio.

[mb911]

Originally posted by JMA-RUF
Thanks Ben... Very nice and neat setup. How does it perform on the road? Those runners look quite long.

Don't know yet but this is what www.autosportengineering.com uses it is basically a a kit you buy from ssi and add the elbows and weld it up..

I can tell you my last setup was very similar that we based off of ssi and it was at full tilt by 3100 or so.. If you search "well I finaly started" thread you will find my whole thread on my turbo experience it is about 10 pages long maybe more..

[Porschefile]

Originally posted by JMA-RUF
OK, I just did and it recommends a T60-1 Fullsize, STG V, 0.68 A/R.

What the heck is a STG V? Is that some sort of T3 housing/turbine?

It says this turbo will support up to 450HP, which leaves me a little head room I guess

You definitely don't want a stage 5 (T350) turbine. That's overkill if you only want 400-450fwhp, and it will just cause unnecessary lag. A .68 a/r should be just fine for what you are looking for, and it will still easily make over 400whp. I'm running a T4 .81 exhaust 60-1 and at 1bar I made 431whp.

A Gt3076r (gt30r) with a .82 exhaust or possibly a slightly larger exhaust housing would be extremely responsive on a 3.2l. I wouldn't go any smaller than a .82 (well the divided .78 is close enough) as it's unnecessary with a 3.2l. You'd have 1bar of boost before 3000rpm. IMO, a T3 hotside is a bit restrictive considering the displacement of most of our motors (usually 3.2-3.6l). I'd just do a T4 but, that's me. There's nothing wrong with doing whatever works though.

Precision's SC series turbos are worth considering: Link Lots of custom stuff isn't listed but, I believe many of them have ball bearing options and you can choose T4 hotsides. Anyways, these SC turbos are usually ~$850 new and are excellent quality. I believe someone on this board is using one. Sounds like you'd probably want one like the Sc34 or Sc44.

[JMA-RUF]

Thanks all, for your responses and advice... much appreciated.

I'm really tempted to go down the GT30R BB path as some of you have suggested, or even perhaps the Precision Turbo route, which would certainly be cheaper than the GT BB.

I'm told, with the 3.2 motor, I can just do a quick top end job and fit some C2T head gaskets to lower compression to around 8.8:1 and then I can safely run 0.85bar for approximately 485HP.

Have any of you done this mod? If so, how well does it work/perform?

[Lukesportsman]

James,

You've basically described Protomotives recommendations so i would say several have done it. Merv is the most vocal on here from Protomotive but NOT the only one. 8.8:1 is OK with EFI and boost they recommend, but what I DON'T like is the increased squish area at 8.8. The Fast and Furious guys all do this kind of thing with running spacers under their heads of Japaneese cars.

It obviously would be better to swap pistons, but that surely increases the difficulty. Run a big I?C, keep AFR's a little rich and check EGT's. I was very close to going this route before deciding to go more hard core. I think your locked in at that level then and don't get greedy with an adjustable electronic controller on those cast pistons.

You may ask Merv if he swapped cams at this stage or if he had to wait till he swapped P&C's.

[WydRyd]

hehe, you're right, I'm a pretty avid Protomotive fan and have a lot of respect for what Todd does. He's educated me so much during my journey to forced induction heaven. Of course there is more than one way to skin a cat, but for simplicity sake, I think the Protomotive solution is best for aftermarket conversions

What James is wanting to do is certainly treading into new territory (on this Forum anyway) as I don't think anyone here has gone down this route (i.e: the 95mm P&C's + C2T gaskets).

In my build, I just went straight from stock 3.2 (0.7bar) to 97mm Turbo P&C's & GT2 CAMs.

My advice would be, if you are looking at running more than 0.7-0.85bar later on, cut your losses and go with forged turbo pistons now, otherwise you'll have to tear it down again and fit them later anyway.

Options are:

- forged 95mm JE turbo pistons (7.5 - 8.0:1) in your existing cylinders
- bore your cylinders to 98mm, replate in Nikasil & get 98mm JE's
- get some 930 turbo 97mm P&C's and slip those in.

You can improve piston cooling by running larger 2mm piston splash valves, but that requires a complete engine teardown and splitting the case

At the end of the day, it depends on how much power & drivability you want and how deep your pockets are