pcabe5

My HY would hit 34psi with wastegate disabled by just flooring it. I swapped turbos to the HX35 and now I can only get 28-30 psi by just flooring it. The only place I could think that a leak could be is at the O-ring seal for the compressor to down pipe and the clamp it tight. Boost elbow is brand new.

Am I just not loading it enough to see higher boost #'s?

EGT's seem to be 100-200 degrees cooler and I have a really nice turbo whine out the exhaust .

RowJ

Exactly right. Bigger turbo will give you same amount of air as a smaller turbo with less boost. Another way to say that is you would need bigger injectors to get 34 psi out of a bigger turbo.

What your getting now is probably about the same volume of air you got from your HY35 but it is much denser (cooler) air, thus lower EGT's. Should be more HP. Lower PSI is not a leak.

Anything over about 30 psi on your HY35 was getting into the super heated range (too high an rpm on your compressor) and actually costing you HP. Keep your HX under 34 +/- psi for max efficiency and power.

Good Luck!
Rowland

pcabe5

Rowland,

Thanks for the reply. I was hoping that was the case with the bigger turbo just needed peace of mind to make sure that I wasn't forgetting something or something is leaking. Seems we have similar mods (exc TST and turbo). What kind of boost numbers do you show and have you dyno'd yours?

RowJ

Have not dynoed since adding TST PM3 and changing injectors. I had DD2.5's and an EZ at last Dyno and got 340 hp on a Dynojet.
The KSB-1B added 20 hp by itself; I can get 48 psi boost. Didn't like all the smoke in city driving. With EDM 1.5's & the PM3 would expect to be over 400 hp.

We have a Dyno Day on the 15th on a Dyno Jet, and I found a Mustang Dyno not to far away (which I believe gives more accurate (and lower) hp/torque readings. Plan on doing both within the next 2-3 weeks for comparison test.

Have read 2 books on turbos since I started my Bombing Odyssey. The more I learn, the more sophisticated I realize turbos are and the more I realize how little I know!
Rowland