Opinions GTX4202r, GTX4294r or GTX4508

[oldsmokey]

Hey guys Im kicking around the idea of swapping out my old tv7512 primary for a ball bearing turbo. Top turbo is a 3788r hybrid with the smaller turbine side from the 3782r. I spoke with Tom at turbo resource and he recommended the 4202 as I want to keep spool as quick as possible. Im just a little unsure what it will support. My current setup with the 7512 regularly dynos 800+. With the turbo swap I would like to increase the duration a little and shoot for 900 on fuel. The 7512 is around 95 lbs/min where the 4202 is around 115 lbs/min but at a higher pressure ratio (I think with the gtx wheel)?

Any suggestions?

 

[DRTurbo]

Hey guys Im kicking around the idea of swapping out my old tv7512 primary for a ball bearing turbo. Top turbo is a 3788r hybrid with the smaller turbine side from the 3782r. I spoke with Tom at turbo resource and he recommended the 4202 as I want to keep spool as quick as possible. Im just a little unsure what it will support. My current setup with the 7512 regularly dynos 800+. With the turbo swap I would like to increase the duration a little and shoot for 900 on fuel. The 7512 is around 95 lbs/min where the 4202 is around 115 lbs/min but at a higher pressure ratio (I think with the gtx wheel)?

Any suggestions?

GTX4202.....no. They are picking a turbo based on compressor flow and have ignored totally the most important part which is turbine side. Most gas based shops don't worry about turbine flow since it doesn't effect a gas motor to the extent it does a Diesel. That turbo would not support that level of power efficiently no matter what A/R you put on it.

 

[oldsmokey]

Thanks. I spoke with someone at your shop today that said am s480 with a .91 wheel would be a fast spooling primary with plenty of air. With the 4202 out of the picture is the 4508 the turbo to pick. how does your new s480 compare in terns of spool

 

[nwpadmax]

I would think an S480 would work. The turbine is in the same ballpark (96mm updated aero BW wheel vs. 99mm older TV75 wheel). Plus they can be had pretty cheaply and often come up for sale used at very reasonable prices. If you don't like it, pass it on...

GT4508 would definitely flow significantly less on the turbine side than what you have now. If you for sure want a Garrett, the 80mm compressor is probably appropriate but you would be wanting a GT47 (93mm) or GT50 (99mm) turbine. This will most likely be the more expensive route.

BTW the GT37s have the same turbine side...the 82 vs 88 in the suffix refers to the compressor. I would think going to the 88 would be a step in the right direction...

 

[DRTurbo]

Thanks. I spoke with someone at your shop today that said am s480 with a .91 wheel would be a fast spooling primary with plenty of air. With the 4202 out of the picture is the 4508 the turbo to pick. how does your new s480 compare in terns of spool

I think your refering to the 92mm turbine wheel from Borg Warner. Probably with a 1.0 or 1.10 T6 housing. Yes that turbo would spool great, little slower then the GT4202 based on the GT42 being a much smaller turbine wheel (only 82mm)