rlm328

I don't know why you insist on the GT30 being to small. I am making 350 rwhp and 370 ft-lbs torque with 14 psi boost. The reason I am not running more boost is that I ran out of fuel pressure. I have a flat torque curve peaking at 3500 rpm. With a fuel pump to allow me to reach 17 psi I will be pushing 400 rwhp. That is a lot in a 2600 lb car. It eats 996 specs, will beat the older GT3s and will keep up with C5s. So if you only want to drag race why stop at a GT35?

Paulyy

in a 3L ?

mind you a "gt30" is a gt3076r not a 71r

I said "that you don't choose a turbo of its over all potential, you choose one that works well with the engine."

You can put a gt3076r on a 3L but you can also put a gt3582R on a 3L
with the gt3076r i can guarantee you'll be missing some top end power. I dont actually see a point of a gt3076r on a 3L as a gt3582r/.82 can spool up 1bar boost at 3200-3400 rpm and easily have 400-450whp

Xaerran

Yea, Fuel is usually the issue with the 3.0L. I am assuming you are moving to a 5bar and 160# or something similar?

rlm328

Yes it is a 3 L, the Bosch 044 is capable of 300 l @ 5 bar so it should be capable of 450 hp. I already have one of CEP's fuel rails so that should not be an issue about over pressuring it. Still debating improving the injectors as they are 72 lb. But that will be an experiment for later.

Paulyy

what rear housing are you running? i wouldn't be surprised if your top end is running out of steam. having 370 ft/lb torque with 350rwhp really sounds like you have a lot of bottom end but lacking top. Not a bad thing depending how you drive and types of tracks you're on.

Got a dyno chart? Wouldn't mind having a look at it.

Thom

The only GT30-sized turbo I tested on my 3L 8V was the GTX3076R, and used with the 0.82 turbine housing AND the stock intake AND stock 9R cam it gave a nicely fat midrange.

It did run out of power above 5500 rpm (though with none of the back pressure-induced parachute drama of the KKK-style turbo it replaced), regardless of intake and cam, but the 1.06 turbine housing helped filling the relative lack of punch above 5500 rpm at the cost of slightly increased spool, again with the stock intake AND stock 9R cam.

With that said, now that I am running a GTX3576R which uses the same compressor as the GTX3076R, I can only imagine that a GT3076R or the very similar GTX3071R will offer a broader usable powerband than the GTX3076R if used with the stock intake AND stock 9R cam.

The GTX3576R I later upgraded to is a much better turbo than the mismatched GTX3076R but is in my experience "too large" to perform decently with the stock intake on a 3L 8V. It runs amazing with a short runner intake though, way better than the GTX3076R.

If I were to make further comparison tests I would purchase a GTX3071R, fit it to my remaining Tial GT30 1.06 housing and see it how goes with the stock intake and stock 9R cam.

To sum it up :
- Stock intake with stock cam : GT30
- Short intake, regardless of cam : GT35

Voith

Shawn is using single 044 and is making 530+ RWHP.

OP: check EFR range of turbos, they use titanium (gamma ti) turbo wheels and shafts which cuts weight of rotating assembly by 50%, use massive (compared to garrett) ceramic ball bearings, both side double ring sealing etc.

http://www.full-race.com/articles/efrturbotechbrief.pdf

Player0

None of the garretts will bolt in though correct? I plan to use the stock 2.5l and later 2.7l intakes. I just don't have anyone who can do that fab work.

Player0

It sounds like the gtx 3076 would be the best match for me. I'm more than happy with the power of my car at the track. My top priority is reliability followed by low end torque.

I'd like a slight improvement over the k27 so 400 hp is a nice target. Too much hp would be problematic at the track with my small tires.

I also want to use this thing on the 2.5l maybe so the smaller turbo seems like a better fit. I only have 80# injectors.

But actually installing that turbo sounds super hard. Is there anyone who sells a kit?

rlm328

Only a print out I will need to scan it in. The car is built for low end to mid range power. As most of the tracks I play on have a technical aspect to them.

Player0

Okay, finally back home so I can do some proper research in to a new turbo.

Here's what I found lodged in my air filter.
http://imgur.com/CKc0Yr8

I have good video of the thing as well, I'll have to get it up this week. It sounded like a hose popped off but I lost all power cause of the huge vacuum leak. I can't wait to pull the turbo and see where the hole is.

Player0

OmniGLH: Not sure why this thing went forward. I wonder if the MAF was destroyed in the process. Ugh. I'm assuming it had more to do with the rotor coming loose and it just mechanically spinning it's way upwards more than any air flow thing.

divil

It sounds logical to me that if the shaft broke the impeller would pull itself forwards like a propeller. Although whether it would do that with the vanes almost completely gone, who knows. Maybe they broke off after it shot forward into the MAF area?

Sorry to hear about this BTW. I was at this event too...did it happen on track?

Player0

Yeah, it was right after the esses, I was doing over 100MPH at the time. I wanted to pull off in a nice safe place to the right in the bus stop but I lost all power and momentum before I made it so I had to pull off in the center grass there, confusing the heck out of some poor guy who caught up behind me. Glad no one got hurt.

rlm328

GT30 3.0 l 14 psi (max) boost. Boost is controlled by the ECU. Apologies I never learned how to control the size of a file