exhaust back pressure gauge

[T77911S]

anyone have an exhaust back pressure gauge hooked up?

i have been thinking about one for quite a while now.

[Tippy]

I've been wanting to do the same. I've had 3 different turbos and it would have been nice to document the pressure differences with comparison to boost onset.

Backpressure is a huge factor in peak hp.

For CIS guys, I wonder how much one can gain once the fueling is maxed out by simply running bigger AR turbine housings?

I've seen over 50whp gains (I want say 100whp?) on 4-cylinders with no other changes except larger AR turbine housings reducing backpressure.

[Porsche 935]

Back pressure can also build up from too small a waste gate.

[T77911S]

you know i have never really thought about the waste gate (WG) in that way.
i have a tial on mine since my factory one went bad. i ahve heard that the porsche WG was very good but i never really thought in what way was it good, after all (i thought) its just dumping exhaust once max boost has been reached.
how does the porsche WG compare to the tial?
i know the porshce one was a monster and had to weigh 4 times that of the tial.

i have been doing a lot of reading on cams and the ne thing i see a lot is how back pressure is a big issue and that there is a lot of HP being wasted there.

[Tippy]

Back pressure can also build up from too small a waste gate.

Ditto!

[jsveb]

Would be interesting to log.
I believe Spenny has mounted something like this:
Exhaust Back Pressure Install Kit - 4 Channel Wideband

[smurfbus]

I've done this on my 930 and IIRC reported it here too?


This is what I used (Aprilia exhaust extensions) with LM2 pressure channel and a separate 3bar pressure sender to log the data.



EDIT: Found the thread.

I had some strange boost ramp up problems after correcting my distributor green wires so I measured back pressure to get better understanding of whats going on. That was with a smaller turbo than the current holset.

"I measured my backpressure before turbo and it's not bad at all. On 3rd gear WOT it's only about 1.3bar max and about the same as the boost (0.1-0.3bar) on cruise on highway"

"I just checked the last log and the pressures are accurate. Same 1.2 bar on 3rd WOT at 5000rpms on my gauge and the innovate LM-2 log (1.2bar backpressure at about 0.8 bar IC boost pressure)"

"Took the turd out and it says K27, 7200R on it"