Lost compression at drag strip

[buickGN3:16]

Ok so i was at the drag strip last friday night & on my 4th run my car started hesitating about the 1/8 mile point & now its down a cylinder, compression test shows the middle cylider on the passenger side with 0 psi & all the others were between 130 & 150psi. I put a little oil in the spark plug hole for the bad cylinder & tested it again & it didnt help. Rockers springs & push rods look good in the head. Possibly a cracked ring or a burnt piston? Scanmaster showed 780 so i guess i leaned it out huh? Fuel pump is a 255 & injectors are 42.5 lb 009's. Any one have any advice??

 

[MeanBuicks]

I say you pushed the headgasket out of that hole; been there, done that. Easier fix than ring/piston too.

 

[Pronto]

Probably pushed the gasket out. Pull the intake, its probably poking out.

 

[buickGN3:16]

So that would cause a loss of compression? I was about to pull the engine out!

 

[earlbrown]

it will pump compression into the valley area and blow smoke out of the breathers. if the head gasket blows to the outside you'll hear it a mile away.

 

[TurboBuRick]

Smacked a valve?

 

[turbodave231]

HG party time!

 

[buickGN3:16]

The breathers were deffinately oil soaked & i had to drive it home an hour from the track, it never temped past 180degrees without the fan but burned a quart of oil & smoked really bad! The coolant level wasnt low either.

 

[Chuck Leeper]

What kind of instrumentation is in the car?
Do you have any data to post?

 

[buickGN3:16]

i have a auto meter pro comp water temp gauge & matching boost, fuel pressure & oil pressure. And scanmaster of course. But i have my fan on a switch that i cut off & on as i need it. And of course the caspers knock alarm.

 

[Chuck Leeper]

Ok. So what was the Scanmaster reporting while you were making passes???

 

[buickGN3:16]

The only reading i observed was the 02 readings which was .780 at wot,

 

[Ttype6]

The only reading i observed was the 02 readings which was .780 at wot,

Where,in the run,did you see .780? Did it record any spark retard?

 

[buickGN3:16]

mainly on the top end, high end of 3rd gear & i shift to 4th just shy of the end of the run. Didnt see any spark retard but do u know if theres a way to go into the scanmasters memory & check for that info??

 

[Ttype6]

mainly on the top end, high end of 3rd gear & i shift to 4th just shy of the end of the run. Didnt see any spark retard but do u know if theres a way to go into the scanmasters memory & check for that info??

As soon as you go full throttle,the Scanmaster begins recording. After a run/before you turn the ignition off,push the right button and the display will show the highest degree of spark retard and the lowest O2 number. If you press the other button while holding the first,it will show the MPH that these numbers were recorded

 

[buickGN3:16]

Ok thats good info so thanks, but i guess its too late to know now but wouldnt a 255 flow pump & 42.5lb injectors be plenty fuel supply so it wont lean out? Im not sure what size the turbo is by the way. Maf is 3" w/ translator

 

[earlbrown]

do a compression test. That should tell you what hole you hurt. If you have access to a leakdown tester, that would be a much better test.

 

[Ttype6]

Ok thats good info so thanks, but i guess its too late to know now but wouldnt a 255 flow pump & 42.5lb injectors be plenty fuel supply so it wont lean out? Im not sure what size the turbo is by the way. Maf is 3" w/ translator

If your fuel pressure rises one for one with boost,your fuel supply is good. Seeing .780 at the top if 3rd is what your supposed to see. If you see .780 as you first go WOT,you're lean.

 

[buickGN3:16]

I couldnt see the fuel pressure gauge because the light on the gauge dosent work & i raced at night.. i did compression test & center cylinder on passenger side has 0 compression, & the plug was wet. i didnt know if head gasket would cause this issue or not.

 

[earlbrown]

Wet with what? oil or water?

Pop the radiator cap off and check if there's any oil floating on top of the coolant.

And drain the oil and see if coolant comes out first.