Powerlogger

[Scoobum]

Okay. I assume that's a 255/60/15 tire. I plugged the info into the Wallace Racing Calculator...a nd the slip for that convertor is 17.9 percent.

[Shimy87]

I run 17 inch wheel so its a 275/40/17 nitto nt50r thats 26 3/16 tall. Your way past my understanding. ...is 17.9 % good , average or bad?

[Scoobum]

The circumference for that tire is 83 inches. Plugging in the new data the slip checks in at 13.9 percent. Not bad for an unlocked convertor.

I'd try 1-2 pounds more boost...and see if it picks up on the top end charge.

Think of convertor slip as a clutch slipping on a standard trans. It's not putting all the power to the back wheels.

[Shimy87]

Ill give it a try....thanks!!!

[Shimy87]

update on my slow top end. Did a compression test Pass side from front to back, 152,155,155, drivers side front to back 140,143,130. Test was done cold. Obviously I have a compression issue on drivers side. Should have done the head gasket on that side also when I had it apart just to know its good. Now don't know what to do. Maybe winter project, pull motor and rebuild?? 

[TexasT]

Put a squirt or two of oil in each as you test and do the test again. Might tell if it is rings or the valves.
I don't think 130psi is too awfully bad. Is is within 20%.

[gusszgs]

Shimy, do it warmed up too

[Shimy87]

Wasn't really concerned about actual number as much as variation between cylinders. The pass side with the new head gasket is good, the drivers side is not, and the cylinder with 130 is 25 under the pass side. If it was within 10% I'd live with it. But 25 lbs. low is a lot, and I still get a hint of oil out that side valve cover breather. That low cylinder also had a piece of the sparkplug porcelain chipped off by electrode. I think the smart move is to pull that head and see whats up. I hope piston and rings are ok and maybe a new head gasket will solve the problem??

[Shimy87]

Had a chance to wrench a little. Pulled the rockers to close valves and put some air to the lowest cylinder. Got the stethhose out and listened in the intake, exhaust and dipstick tube. I hear no hiss in intake, clear hiss in tail pipe and unfortunately hissing also in dipstick tube. Had to quit but pretty bummed, was really hoping not to hear any hiss in the dipstick tube

[Shimy87]

update, pulled it apart yesterday and taking heads in for valve job. In listening with scope, I put air to the lowest cylinder and it is really leaking out the exhaust port. I also listened in the crankcase and then put air to the "best" cylinder and listened to the crankcase and the air sound was exactly the same. I'm hopeful that doing the valves brings compression back to within 10% varience.