For those with the GTM kit, has anyone gone from like a stage 2 to a stage 4?

I'm looking at going from GT28RS to GT3076R's, however it's been a bit challenging getting anything out of Gamma as of late in this regard.

I'm curious if anybody on this board has done this before to the GTM kit, and basically if the turbo upgrade options were just direct bolt on without any modifications to piping etc.

I'm also considering going GTX3076R for a little newer of turbo than it's older counterpart but trying to avoid as much custom hacks as possible to make it work.

These days it seems everybody goes V-Bands, but ideally I'd like to stick to the original flange types that came with the GTM kit to hopefully eliminate custom work, but I am a little concerned if the bigger turbo's would hit anything, but I don't *think* that they used different turbo manifolds for the larger stage options they previously offered, but I'm not sure if the piping was any different...

 

I'm not sure if you already know this, but the GTX30 series is a t3 based turbine housing where as the GTM manifolds are flanged for t28. The biggest t28 I believe is the GTX2871 which flows about 80 hp less than the GTX3076, however two of the gtx2871's are still over 1000 hp at the crank.

 

Yea thanks for the response,

It kinda fizzled out when digging into it more as it looks like to really play nice AR wise, custom manifolds are needed for the better flowing flange type. The GTX3076R has a T25 plus option (at least from ATP) turbine housing (looks the same as a t28 although not sure dimensionally - would need to dig deeper) with a 2.5"/3" V-Band outlet, which is still some custom work on the downpipes.

Was wanting to go larger for eventual re-use on a LSx project but not too big that it would be lag country vs lag city on the 3.7 haha.

 

T25 will limit top end, but good enough for a street car. The best bang for the buck might be to have your existing turbos upgraded with an HTA billet 68 mm compressor wheel. Your spool will remain the same and you'll pick up maybe 100 whp (equiv to GTX wheel).

 

^Thanks dash, that's certainly an option. I'm also considering brutha's GTX2871R's as well as he mentioned they come in the same flanges (would assume getting a .86AR for more top end on that setup). The 2871R seems a little surprising considering it's only 80 off from the 3076R, but I'm assuming if mated eventually to a larger motor setup that the 2871R would fall off vs. the 3076R - but 1K CHP still sounds like a lot even for a potential v8 use later. Haven't really seen any v8 guys using 2871R's specifically though to consider as a long term upgrade but sounds like they would support a lot of power considering their size.