Backpressure Question

bricewise · Aug 8, 2014

From what I've read about back pressure your looking for 1:1, 1:1.5 ratio and 1:2 at max. Is that correct?

I recently started watching mine and it seems like until my 4094 starts spooling I'm seeing anywhere from 1:2 to 1:3 boost to back pressure. Is that normal? Should I be concerned about exhaust leaks? Or any other concerns? Or am I just being a hypochondriac?

Fast-6.0 · Aug 8, 2014

VGT turbos will typically run more bp than boost by design. That's why Non-VGT turbos make more top end hp because they can run 1:1 bp to boost.

Our truck runs 32psi and 52psi backpressure at WOT with the 4094.

WhiteMamba_Scorpion · Aug 8, 2014

How much boost can the 4094 make?

bricewise · Aug 8, 2014

Fast-6.0 said:
VGT turbos will typically run more bp than boost by design. That's why Non-VGT turbos make more top end hp because they can run 1:1 bp to boost.

Our truck runs 32psi and 52psi backpressure at WOT with the 4094.

Well that makes me feel better. I knew I'd be pushing more BP simply as a result of it being a VGT but was curious if I was in a range that was fine.

And it sounds like you answered my question. Thanks Tadd.

Fast-6.0 · Aug 8, 2014

WhiteMamba_Scorpion said:
How much boost can the 4094 make?

I would say should be in the mid 30's. We are at 5500ft, so the crappy air here limits our boost.

WhiteMamba_Scorpion · Aug 8, 2014

Fast-6.0 said:
I would say should be in the mid 30's. We are at 5500ft, so the crappy air here limits our boost.

Ok, just curious. It's nice to have some background info so when my trucks done I can check the backpressure too.

In case you didn't know my truck is the one Jared at RCD is building currently so you should be seeing my trans soon :thumbup: Looking forward to this new turbo setup