dizzyj

I currently have a k27/8 that I rebuilt recently. Its a beast, but the amount of lag doesnt work that well for racing. I think I'd get better laptimes with a smaller, quicker spool.

I really dont want to modify any pipes, so that seems to limit me to the LR "super" dbb turbos. But which one? I'm thinking the 48, or 53. Anyone have experience with these? how do they work on track? I'd like to feel the kick in the rear between 2k to 2.5k rpms. Right now I dont feel it till ~4k.

Rogue_Ant

No turbo that makes any real power is going to hit full boost at 2-2.5k rpm... (other than possibly a VNT unit)
On the track you really shouldn't need to be that low of RPM anyway.
Try advancing your cam, which will bring more power earlier in the rev-range, and help boost come on quicker.

CyCloNe!

Seems like a lot of people are happy with the Super 53, which I think is a 60 trim wheel. I have the 48 and it does well but for racing you may like larger. Mine puts out a little more than a k27/8.

Paulyy

How much work do you want to do to change your turbo? bolt on or not? because the gtx3076R with a .63 ar would be the best option OR the gtx3071R with a .82.

dizzyj

I raced at cota this past weekend, and there are several spots that I had to shift down to 2nd, and STILL was out of boost. I've never dyno'ed my car, but when you finally feel the big whoosh of the turbo, is that under full boost? or is that when it starts boosting?

dizzyj

so jump a notch or two on the timing belt? guess I should try that first? last thing i want to do is drop $1200 to have somthing that is almost like what I have.

Paulyy

There's other things you can do to reduce spool.

Things like a free exhaust, dual port wastegate and a free intake will bring it down.

Other things will help bottom end is the N/A cam

Paulyy

Even convert it to a 27/6 but you'll loose some top end.

dizzyj

got all that. 3" free exhaust, lr dual port wg. mtune, etc. car is pretty trick, once on boost

Crazy Eddie

I have an old version Stage 2 (quick spool option) Vitesse turbo kit with SMT6 and his MAF chips etc
The car is a beast ... I am more than happy with the power it puts out...
I typically only run the boost at 15 on the regular S#%& gas we have here in CA
Otherwise, I run race gas (100) and that's usually when I have Tom by my side, nudging me to turn up the boost
I have driven in Tom's Vitesse Stage V ( He has a 3 liter) is absolutely sick...
Good luck

rlm328

First question would be what is your class. If you are running one of the stock classes, then the K's are your choice. If you are running one of the GT classes then your turbo is free and you will want a Garret GT30. Depending on what you put on the hot side will determine how fast you spool and what your compressor efficiency is.

Rogue_Ant

No! That will be waayyy too much change.
Pickup an offset cam-key or fully adjustable cam-gear. Dial in 4-5° advance. And see if you like the results..

Reimu

Why are you near 2k-2.5k rpm at the track?

Also have you gone over your system for boost/exhaust leaks? I don't think a k27/8 is supposed to be that laggy.

333pg333

Exactly. The only time you should be anywhere near that low an rpm is in the pits. Do you have any in car video? You were there with the Aussie V8's yes?

dmcampbell

"3" free exhaust, lr dual port wg. mtune, etc."

What are other etc. mods you have? Get the car dynoed, and then share the HP/Tqe curves. Thanks, Mike