Popping and spitting issue unresolved.

[robertf]

So since I started this thread: http://www.turbobuick.com/threads/car-still-pops-and-spits.446331/#post-3715829
I've lost pass headgasket. RR headgaskets {OEM}, Flowmatched 60lb injectors/TT 5.7 Street chip combo {18psi}. Previous was older 5.3 TT Alky chip/50lb injectors. Got it started yesterday, Still idles a tad rough but not my concern at this time. Car is really snappy driving around town. above 12 PSI I'll get an occasional pop {very scary}. At 10 PSI boost, fuel PSI is 60. I'm really gunshy of pushing further than 10 PSI of boost at the moment.
DO NOT want to lose another headgasket.
Current mods are:
Champ ported heads.
Champ portmatched intake.
70mm TB.
Bailey TR6.
TA49.
Stretched intercooler.
3.5 MAF/Translater plus.
Fuel PSI is at 43. bumped to 45 with no change.
I believe Walbro pump.

So where do I look from here. I did adjust my regulator to 80 PSI {vac line off}. Is this an good way to check the pumps output? Should I look into a better fuel pump? I'm just stumped.

 

[robertf]

Just a side note. The Heads have fairly low miles but the car sat and was driven very very little for a number of years. Is it possible the valve springs can go bad from that?

 

[Toby_Goodmk]

sounds electrical, Make sure the obvious suspects are looked at...firing order etc. Also make sure the plugs are gapped correctly. If you let one drop they can bend the strap over and cause drivability issues. You have the TR6 so make sure you have the settings set correctly. If it were my car I would have a known good factory module put on the car and see if things feel different.

 

[mikestertwo]

Powerlogger file?

 

[cork]

Are you running alcohol injection? If so which kit?

 

[ITSAV6]

What is your battery voltage doing when it pops? Coil pack or LS coils? What about grounds on back of head?

 

[robertf]

Guys I believe I've cured the issue. Replaced the UR5's with a fresh set {they were gapped at 40} and tightened the gap as per Toby Goodmk's advice and presto, shes pulling like a GN should.

 

[robertf]

What is your battery voltage doing when it pops? Coil pack or LS coils? What about grounds on back of head?

FWIW, while reassembling the heads, I ran numerous heavy ground wires to insure better than factory grounding.

 

[earlbrown]

Something's up with your fuel pressure. 45 base plus 10PSI should be 55#s not 60.

At least it's high instead of low. Any chance you have a cheap fuel pressure gauge?


If it wasn't like this before the engine work, any chance you pinched the return line a little?

 

[robertf]

Something's up with your fuel pressure. 45 base plus 10PSI should be 55#s not 60.

At least it's high instead of low. Any chance you have a cheap fuel pressure gauge?


If it wasn't like this before the engine work, any chance you pinched the return line a little?

Earl it's liquid gauge that was in the box that came with the car. I hooked it up and layed it across the WW wiper and drove down the road. I have a Kenne Bell hood mount gauge I may install tomorrow to get a second opinion. It's also an older Bosch regulator. I'll know more tomorrow as I ran out of daylight. I am curious to see if theres any difference in gauge readings.

 

[earlbrown]

Pretty sure you found the difference. Those gauges are cute, but they aren't anything you want to trust your life with.

 

[Toby_Goodmk]

TR6 needs looked at, like mine before I switched for regular module and coil pack I took the advice from some smarter than thou and shortened the gap, and poof things were good.