Ok guys I'm thinking maybe the piston slap in my truck is that bad that I'm loosing boost now.

OK I have a Metco upper pulley and a PSP lower pulley, and I'm getting around 10.5 max boost with an autometer gauge. Now I have heard that many of you are getting allot more boost then this with just one pulley, so I'm thinking that this might be a good way to see what the problem could be without removing anything yet.

So what do you got for boost? And not a educated stock gauge estiamte, those arn't even close!

thanks for the input
Later Joe.

 

Joe,

My autometer guage shows 10-10.5 with the stock pulley.

Mike

 

I have the autometer boost guage.Am running a smaller SHm upper pulley and Johnny Lightning lower pulley,boost is about 14.5 lbs.
Jerry

 

14psi @ 5500 RPM

Autometer gauge

 

As far as I know, boost is a measurement of pressure in the intake manifold, not the cyclinders..If your intake is leaking or intake valves are burnt,bent, and not sealing you would loose boost. Run a compression check on all cyclinders,,good luck..
Ted O.

 

Well I guess that kinda seals the deal there huh.

I'm pretty sure tha between me and J-man we should have about the samw boost if everything was OK, but I must have some kind of problem.

I seriously can not get over 10.5 pounds of boost, and everyone that listens to my truck ask me whats that tapping noise . I guess that is enough for me to conclude that I got a valve that is messed up then huh. I kinda thought that could be the problem after spiro said something to me about it. DAMMIT TO HELL, This is going to break the bank for the next few months. I'm so freaking pissed now.

I guess its time to start pulling intakes and manifolds off . hey there's first time for everything right! I need the experience.

Thanks guys, keep the numbers comming and let me know what else you guys could think of that it might be, I'll try anything to get my baby back into shape again.

 

Killa,, really do a compression test before you start pulling heads. I don't have a shop manuel for the Ford but I'm sure someone has one and can tell you what they should read..
Ted O.

 

8.4 to 1.

I'll try and do one this weekend. Thats going to be a job, I can tell you that already

 

Killa, My dodge was around 180 #'s per cyc. and they should all be within 8-10 #'s of each other..Not sure about the "L", but they should all be within 6-10 pds. of each other..That will tell you what cyc head has the bad valve..
Ted O.

 

11.5 #'s @ 5300 RPM. JL pulley, autometer gauge.

 

Sounds like valves to me. If you nipped a piston, it wouldn't effect your boost too much. Theseengines appear to have valves in them that won't take a lot of heat for an extended period of time. Run a leakdown test on it.

That will tell you where the leakage is before you disassemble it.

I'd look for a manifold leak first, or possible blower damage. What was your boost when you first installed these pulleys?

 

Killa, my gauge (Autometer) with Sal's lower pulley has never gone over 9 psi. I think it could be the gauge. My truck is just as fast as others with the same mods, even though their showing 12-14 lbs. I'm going to try another gauge.

 

That sux Joe. I know with the PSP lower and at 5600 rpm I see around 12-13 lbs of boost at the manifold. Shoot me an E-mail if you need any help.

 

I was told by the tech, '99 & '00 L should be 175 psi on compression test.

 

Is it different on the 01's?