Here's my setup:

VT Competition Engine (8.8:1 CR, JE Pistons/Rings, Eagle Rods)
MLS Head Gasket
ARP Head Studs
Boosting 10 lbs with Vortech SFMU (2.72 disk)
Fuel Trims on Pocketlogger look good (Idle: STFT hangs around -2/+2 and LTFT is -17, under boost the A/F gauge always is buried in the green)
Exhaust Temperatures never go higher than 1400 degrees
94 Octane Gas Always used


A couple of months ago, the car would leave about a dime sized spot of oil on the ground. Looking under the car, you can see residue at the bottom of the transmission bell housing. This engine already had the rear seal replaced once so I am confident that the rear seal isn't the issue (Old Story: First time the new motor was installed from VT it leaked ten minutes after startup. VT used the wrong rear seal. The seal was replaced with the correct one).


Now the other day, I got a check engine light for cylinder 4 misfire. I figured I may have fouled a plug. This afternoon I took all the plugs out and they looked fine. I decided to do a compression test. The first test yeilded (engine was fully warmed up):

Cylinder 1 through 4 (185, 185, 185, 120)

Woah. That surprised me and would explain why the cylinder is having a misfire. I decided to retry the test after two capfuls of oil was put into cylinder #4. It went to 125 psi. Not that big of a change. I am going to assume the oil leak and low compression are due to a blown head gasket. This would surprise me though as it is the MLS metal head gasket.


What do you guys think? The car is going to my mechanic tomorrow (a friend of mine) and I am going to see what he says.


Thanks,
Kurt

1. check for oil in the radiator overflow
2. have someone do a leak down test
3. on the right side of the motor is the vacuum line that is supposed to go to the air intake. whatever is on it, take it off and see if you have any oil vapor coming out.

james

I took the cap off of the radiator overflow and it looked normal. I also pulled the dipstick to see if any air was coming through. Nothing. Seemed normal. The car also seems to run/idle just like before. No big change.


I'll have to see what tomorrow holds. I'm hoping for the lesser of the two evils (headgasket).


--Kurt

COuld be a bad valve, or a blown headgasket. Blown headgaskets don't always mis oil and coolant, and can be a huge PITA to dianose in such cases. I blew mine into the waterjacket, and aside from an intermittant overheating problem, i never had any issues - not even low compression.

Do a leakdown test - just get that cylinder at tdc and blow some compressed air into it, see where the pressure vents from.

Here's an update. I got the car back from the mechanic yesterday but I didn't make it back here to post up the results. He said the gasket is definitely leaking and needs to be redone. He also said that the camshaft seals are leaking (not a big deal as they will be redone at the same time as the head gasket).


I didn't get to talk to him for very long but I am assuming that this plays a big part in my low compression in the fourth cylinder (I'm going to double check tomorrow). Anyone had a similar experience?


I was wondering everyones opinion of whether or not I should go back to using a regular gasket instead of the MLS gasket as this one did not seem to hold up at all. This gasket only has 3,000 miles on it and extreme care was taken when the car engine was built (used ARP studs and bolts torqued to recommended specs of 70 ft/bls and used the copper gasket spray material). Also could the ARP bolts be reused after a measely 3,000 miles?


Just as a side note, the car was broken in for the first 1,000 miles and saw no boost. I boosted it about 500 miles at 8 psi and then turned it up to 10 psi. That was the highest this motor has seen.


--Kurt

I would run another MLS headgasket, there really is no better for our cars.....and this time I would torque the ARP studs to 90lbft's. I think you should be okay using the same studs...but I'm not %100 on that.

70ft/lbs is nothing. I run ~100ft/lbs.

ARP studs are reusable. They don't stretch like stock bolts.

Was the head decked, and the block thoroughly cleaned before the gasket installed?

If it blew in 3000 miles, something was wrong to begin with, and it probably wasn't with the gasket itself.

The engine came from VT so I am assuming they checked the top of the block for flatness. The head came off of my old motor which had no problems with head gaskets (never leaked) so I never decked the head because of this.

The only other thing I can think of is I was sent the wrong gasket. Are the neon gaskets different from the eclipse gaskets since one is SOHC and ours is DOHC. I ordered the gasket from VT and told them what car is was for. Where do you guys buy your MLS head gaskets from? Dealer?

Maybe there is more to this story and I'll know once we begin to take it apart. I am hoping it is nothing serious and low compression is due to the gasket. I'll keep everyone updated though as we begin to disassemble.


--Kurt