NightmareTA

iTrader: (20)

It seems I may be at the limit of my turbo on my setup. Currently I'm running a stock bottom end 2005 5.3, 317 heads, LS6 cam and intake, and a custom made single turbo setup with a turbonetics 7668. It has the F1 wheel and .96 AR. The car made 540 rwhp on 11 psi, and then 560 on 15 psi. I tweaked the tune and it feels like it's got a bit more power now, but haven't been to the dyno since. Just seems to run out of steam on the top end, and literally every car I race in the upper 5xx to mid 6xx rwhp range is close on the hit and then the pulling gets worse the faster we get. I've been told multiple times that my current turbo may be on the small size for a 5.3.

The car is a T56 car, so with that in mind, can anybody give me some good recommendations on a turbo that'll give me some more umph up top without taking until 5K rpm to spool? I was thinking this may be a good option...

http://shop.huronspeedproducts.com/T...urbo-t7875.htm

stevieturbo

Change the cam

NightmareTA

iTrader: (20)

I honestly don't really care to change it. I love the stock idle and smooth driving. It's a street car and I just don't want to get into swapping the cam because of the work involved. I'm sure going bigger on the turbo, namely the turbine side, should bump up the powerband and give it some more top end pulling power.

IronBlocked

He's right, you can have a stock-ish idle with a .58x lift and 230-240 duration to carry power up to 6500-7k

IronBlocked

also, making all the power+tq so low on the rpm range is really hard on rods

NightmareTA

iTrader: (20)

Biggest issue is that I don't want to kill the stock rod bolts either. If I bump up the redline with a cam, and then start revving to the moon, I don't think it'll last long. The current turbo and setup dies off just before 6K rpm. I'd love to just swap out the turbo if possible. I thought plenty of guys were going fast on an LS6 cam?

stevieturbo

You would need to spec a terrible cam for it not to be smooth and perfectly drivable. A cam upgrade will yield gains everywhere.

A different turbo may help too.

What sort of preturbine pressures are you seeing ?

IronBlocked

You can just swap the turbo too if you want to keep the revs @6k

NightmareTA

iTrader: (20)

Haven't checked pre turbo pressure. Do you have a tip on how to get that measurement? Would I just basically need to get a pressure gauge plumbed into the merge pipe somehow?

All I'm honestly looking to do with the car is raise the powerband up, hopefully through the turbo and not a cam. Not sure if I made it very clear in my original post...it was late when I typed it and I was half asleep lol. Would be nice for it to have more steam up top and pull to 6500ish rpm instead of fall off at 6K.

Thats what I'm hoping I can do!

stoverz28

iTrader: (8)

Is boost falling off up top?

I have the exact same setup but with a 224/224 cam. Only made some 10psi runs shifting at 6k but it pulls very well up top and idles just fine.

pyro719

iTrader: (5)

My on3 7875 5.3 ls6 combo pulls to red line at 20psi. Get a bigger exhaust wheel

NightmareTA

iTrader: (20)

Exact size turbo I was considering, and great to hear that combo is working out good for you. Thanks for the input.