Always had at least 2 lb's lower boost than what been advertised with most combinations.Was running a Kleeman 168 lower and 77 upper and made 15lb's of boost.Now I have a 84 upper and make 12.5 lbs of boost and a very noticeable low/low mid loss in power but.....lower IAT numbers but the ecu isn't making up for the lost power with the extra timing.
The first combo should have been around 17 and this present combo should see 14 or more. I am at sea level. Anyone running these combinations with any data to share ? Thanks

 

Do you have any exhaust work done?

 

Shorty headers and second cat and resonator delete. Mufflers where also slightly bypassed internally.

I see that a 168 and 77 upper is like a 205 mm lower boost wise on the boost chart and that's a big pulley to run but never saw north of 15 lbs so may go back to the 77 upper.
I can say temperatures are around 15-20 degrees cooler under boost with less boost but car is a little low on power even with lower iat's and sightly more timing.

 

What are you using to log boost with ?

 

I use an Aeroforce scan gauge and it always matched any other logging that I did.

 

I know I lost boost when I installed Headers, but I can't say how much it was. I see you have shorty headers.. Would be nice to know what boost loss is installing the headers.

 

Well I know boost pressure is back pressure but this car always seemed to have a lower number even stock. Like I said the 168/77 is a pretty stout combo but it only makes 15 lbs....3 pounds shy of the claimed 17 lb's and still spinning the blower at that high rpm. That's really my only concern.

 

Hmm 3 psi is quite a bit lower, especially you are at sea level. I guess the unit is not a high mileage, or boost sensor issue?

 

New sensor and 60k on car. It has always read low stock or modded. I guess it is what it is. It's making great power so not going to worry about it but was curious as to what others have seen.