GT42R on a 4.1

[CTX-SLPR]

Howdy,

How good of a fit would a GT42R be and what stall would be a good match for that turbo? I'm looking for about 600hp on pump gas and alky and keeping booste under 24 on ported irons or TA SE heads with an 8.0:1 4.1.

Thanks,

 

[GNVAIR]

You might want to talk to Keith Mease as he has actually done this. From what I remember Keith telling me; to use the GT40 or 42 you would have to modify the passenger side header for a 4 bolt flange and make a custom down pipe with an external gate as the turbine wheel is way too large to fit into a 3 bolt housing.

 

[idaho gn]

i do not think a 42 r would be a good choice. that turbo supports 1200 hp in a 76 1100 in a 74. its way to big plus where would you put a 5 inch dp in a buick?

 

[CTX-SLPR]

Not a problem, the downpipe was already going to be custom and I got the deltagates on the shelf. As far as 4 bolts go.... was kind of going ATR 4-bolt anyway. I get to work with the nice comodious engine bay of a 65 Riviera instead of a g-body.

Thanks,

 

[CTX-SLPR]

Besides, I want a water cooled, dual ball bearing center section. That kind of limits my choices to a GT35R or a GT42R. Garrett also only lists the turbo for upto 750hp in its small A/R format. Though its pushing the CID they recommend, 257 is only 4.2L and they want to start it at 4.4L.

 

[salvageV6]

If you don't want to go through all the fabrication email Rick Head at Innovative Turbo.

They make stuff that fits your buildup and fits our cars.

Jack Cotton may also be able to help you out with it.