duncan01

That's what I believe ill do. Just for kicks I stuck a vacuum gauge on it when I got home this afternoon. Im pullin about 11 to 12 inches. Before the head swap I was pullin about 15 to 16. I smoked the engine with a cigar (redneck smoke machine) and didn't see anything. Its not jerky or anything on take off like a typical vacuum leak would be. I would expect some loss in vacuum with new heads but not that much. Maybe im wrong hell its all trial and error. Oh yea, all the lines are new and upper and lower intake gaskets are new and snug to rule those out

mjr46

for the most part yes, the eec iv uses algorithims to do calculations, I don't claim to be a math wiz in that area..lol

holyshift

I like my gt40x heads,i think you'll be happy with them.

duncan01

I like them alot so far just trying to get all the bugs worked out. They gave the car a nice solid sounding hit, and noticeable gain in power.

duncan01

Anyone have any thoughts on the vac reading I posted a couple posts up?

dawson1112

I would think that after the head swap ,if you used new valve springs , rockers and all that jaz your vacuum is probly about where it should be for that cam. What is your base timing set at? Some times you can pull another 1' of vacuum by bumping the timing up a little and resetting the idle .
Changing the volume of air like you did could easily result in lower vacuum

But I would expect a vacuum leak to present it self and either a constant high idle , the engine hunting idle ( meaning rpm roller coasters up and down) , and probly some popping at high rpm or wot.

Check all you connections in the air intake tube after the Maf and before the throttle plate. Any amount of unmetered allowed into the air intake tube before the throttle blade can cause issues like this.

If the engine feels strong and you don't have any other issues other than the hiccup upon deceleration I wouldn't worry to much about it.

duncan01

base is at 14 degrees. Ive checked over and over again. I tweak on it almost everyday after work hear lately. The only thing annoying the hell out of me at the moment with the CAI is the damn whistleing noise through the filter. I think its were the intake tube isnt exactly straight in the throttle body and its a professional products throttle body. I feel a little better about vacuum now, thanks.

duncan01

update: Went down to my tuners place today and stuck the car on a wide band. Holy **** was this thing running lean. Since were not going to tune it till next week cause hes backed up. We upped the fuel pressure from 39 psi vac line off to 58 to compensate. I know that this isn't right but its a bandaid till Monday.

dawson1112

My cai intake whistles too its just one of those things I deal with

holyshift

Yup mine whistled too. Also when its on the dyno "clock" your maf meter in different spots. My car when it was efi lost 5hp when we moved it. Found the sweetspot on it and left it. Also filter,I initially had a small filter on my intake,put the biggest on I could.on and the car picked up et at the strip(didn't think about it on the dyno) just some ideas.