A friend of mine just finished retuning after changing a few thing with his setup. This is what he has

B18c gsr
81.5mm JE 10:1ish
buddyclub spec3 cams
supertech valvetrain (+0.5mm exhaust valves)
Full port and polish
topmount manifold
3” full exhaust w. Vibrant stealth
garrett GT3076R turbo
0.63 a/r turbine
44mm tial wastegate open dump
edlebrock manifold
ID1050x injectors
walbro 255
Hondata s300v3
CPR kit

after tuning he made 470hp and 342tq at 24psi.

He was hoping to get to 500+ but we’re wondering is he maxing out the turbo? We know Garrett rates it for 525hp. Or is it the turbine housing and would going to a .82 or 1.09 a/r get him there?

(I said go for a new G30-770 turbo :D)

 

what fuel type? That walbro 255 has to be at its peak I would think as well as the injectors.

 

Only if on E85. He can go a little more to about 520whp, with knock resistant fuel. But remember, it's only 52lbs/min. The turbine wheel can deliver quite a bit more. Going to a .82A/R or ever 1.03 won't do that bit of good. I've made over 540whp on a .63 A/R with the same turbine wheel as the N111 GT30 turbine. Might be the fuel used.

 

i don’t know much about his turbo, but my turbo is a .65ar and I’m right at 700whp

 

hes on 94 octane, unfortunately no e85 around here in Toronto Thats kinda the answer I figured I was gonna get. Looks like he is pretty much maxed out the turbo with the fuel available. It’s a street car so race gas is pretty much a no go

 

‘still a lot of power on pump gas

 

This isnt a mustang dyno right?
Thos cams were degreed correct? Its not a big cam and 1-2 degrees playing on the dyno changes power at least 5%.
Still decent power on a 55/60 turbine wheel in .63 with just pump gas.

 

There's no "unfortunately" about it, honestly. I'm not really a fan of E85 anyway. (only 4 hours from GTA). I think that getting that power level for 94 octane is very impressive for that turbocharger, so that person should not be disappointed at all. The fact that they're using a top-mount styled exhaust manifold I'm sure changes the behaviour of the turbocharger (in a negative aspect IMHO), but, I think overall, quite well done.

 

So I was relaying what you guys said to my buddy. He appreciates all the input. We were wondering would it be possible to change the compressor wheel on his turbo to get any extra power or change to a larger/more efficient turbo? Or is it mainly the octane holding him back?

 

Water meth injection and he has easy +50

 

Hmm. With about 6-8 more psi, but then you're just creating heat. There are ways to rebuild/upgrade that turbocharger.

 

Yes true.