Twin 64 or 6766 CID question
Twin 64 or 6766 CID question My heavy sedan is size limited to the t3 or vband turbine housing so my max a/r is .81. I think I can squeeze the SP cover on this mid mount kit.
I had originally decided on a built 427 but it seems that might be a bit much and I should step down to a 388. Either would be with a set of as cast BR7s
My goals are a solid 1k at the wheel and *maybe* 1200 at the track.
Would the smaller displacement help me with the probable back pressure issue the 427 would have? I don't need to spin it more than 6500
I had originally decided on a built 427 but it seems that might be a bit much and I should step down to a 388. Either would be with a set of as cast BR7s
My goals are a solid 1k at the wheel and *maybe* 1200 at the track.
Would the smaller displacement help me with the probable back pressure issue the 427 would have? I don't need to spin it more than 6500
I honestly think either will work for your goals. 427 would be better if you're looking for more grunt down low and 388 would be better for max HP up top. I think you're correct in your line of thinking that the 427 will definitely be more prone to BP issues, but with a goal of only 1k or 1200, I think either will get you there. Just really need to think about what your overall goal is for the motor. I personally would do the 388 but make sure the cam and intake is set up for lower RPM. So a mild/medium cam and honestly a stock intake manifold. That will help it make a lot more tq down low but you also still have the headroom up to the smaller CID offers.
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From: Norn Iron
My heavy sedan is size limited to the t3 or vband turbine housing so my max a/r is .81. I think I can squeeze the SP cover on this mid mount kit.
I had originally decided on a built 427 but it seems that might be a bit much and I should step down to a 388. Either would be with a set of as cast BR7s
My goals are a solid 1k at the wheel and *maybe* 1200 at the track.
Would the smaller displacement help me with the probable back pressure issue the 427 would have? I don't need to spin it more than 6500
I had originally decided on a built 427 but it seems that might be a bit much and I should step down to a 388. Either would be with a set of as cast BR7s
My goals are a solid 1k at the wheel and *maybe* 1200 at the track.
Would the smaller displacement help me with the probable back pressure issue the 427 would have? I don't need to spin it more than 6500
So that isnt a limitation.
Some of the new G30 Garrett's are crazy small for huge claimed power potential, although I'd be sceptical of their little turbine being ideal for a large V8
But a lot will depend on what turbos, as much as what numerical size.
Last edited by stevieturbo; Apr 12, 2020 at 05:47 PM.
I honestly think either will work for your goals. 427 would be better if you're looking for more grunt down low and 388 would be better for max HP up top. I think you're correct in your line of thinking that the 427 will definitely be more prone to BP issues, but with a goal of only 1k or 1200, I think either will get you there. Just really need to think about what your overall goal is for the motor. I personally would do the 388 but make sure the cam and intake is set up for lower RPM. So a mild/medium cam and honestly a stock intake manifold. That will help it make a lot more tq down low but you also still have the headroom up to the smaller CID offers.
The cam has been spec'd out as a: 235/242 .666"/.651" 115 +2 LSA with 1.8 rockers.
That's one of the reasons for a big displacement and smallish turbos, to get the car moving easily.
Stock intake, not need for sheet metal or high ram
That really is the limit. I would like to actually drive the car and not worry about having a tow truck on speed dial.
The cam has been spec'd out as a: 235/242 .666"/.651" 115 +2 LSA with 1.8 rockers.
That's one of the reasons for a big displacement and smallish turbos, to get the car moving easily.
Stock intake, not need for sheet metal or high ram
The cam has been spec'd out as a: 235/242 .666"/.651" 115 +2 LSA with 1.8 rockers.
That's one of the reasons for a big displacement and smallish turbos, to get the car moving easily.
Stock intake, not need for sheet metal or high ram
