Quick backpressure question

[TURBOZ]

At 12psi manifold pressure, is 32psi of backpressure in the exhaust too much?

Problem as posted before boost falls off as rpm goes up.

Thanks

 

[TurboDave]

That's not out of line IF you're measuring backpressure right before it enters the turbine housing.

However, if you're measuring that post turbo, there's a HUGE problem with it.

 

[TURBOZ]

That messurment is before the turbo. Presision claims too much, it should be around 14psi before the turbo. The back pressure before the turbo does not seem to go up as rpm goes up, but boost falls off. Im thinking the turbo needs to spin faster to feed the motor but the back pressure is holdin it back. what do you think?

Thanks

 

[TurboDave]

Hmmm, could be. But the turbo manufacturers that I've talked to have said on occasion that, while under boost, the pre turbine backpressure is for the most part as much as double the boost you're making.

So, in retrospect, I suppose 32 is too high. Sounds like a call to Duttweiler, and/or PTE is in order to try and determine if the turbine, turbine housing, compressor and housing are all a good match for your combination.

 

[REDS HOT AIR]

ultimate would be 1 to 1 ratio but it would take forever to spool

stock turbo shold be around 2 to 1 being double pressure on exaust than intake but after market turbo's should be less than 2 to 1

i havent checked mine out but go figure less backpressure is more hp in turn is more mph

if you are trying to cover for a leak under boost like intercooler hose or something leaking it will increase your exaust to intake pressure ratio