http://www.summitracing.com/parts/HYP-4066/

i would still like to know what a leak down test is please

 

I would say factory unless you have a HEI like a msd system system......otherwise you will see no difference on the dyno...its one of those things people like to throw money away on and see imaginary gains in performance... the thing is people replace the shot rotor, cap,plugs and wires along with a perfectly working coil and of course you will see a boost in performance.....(from the other stuff). Of course this isnt only my its what I've been told by serious builders I've talked to that build racing engines for a living..... the only way to see a performance in the ingnition is to go with a true high energy ignition system and not just a factory style epoxy or tar technology coil..(they are limited by that technology btw)

 

thank u, u have a very valid point. can u explain what a leak down test is please thouugh

 

I'm not sure how its done...I know you use a compressor and it checks for leaks in things like valves....Hopefully aim4squirrels can chime in here and elaborate.

 

Those are great numbers!!! I have a number seven with less than 65 and a number two with about 75 but mine still runs like a bat outta hell lol.

To do a compression test: First run the engine to warm it up. Second remove all the spark plugs, remove the coil wire and disable the fuel system. Third place a compression gauge on a cylinder and turn the engine over and record the reading. (Do this for all cylinders)

NOTE- I prefer to turn the engine over manually. This is how we check the compression in aircraft engines during phase inspections.

If you get a low reading you can squirt a small amount of oil in the cylinder and try again. A change in the compression usually is a sign of ring or wall damage. No change is a normal sign of valve wear or a bad valve seal.

 

I hear ya I was just kidding because my engine was blown so I had to either rebuild or move up to a 360. Hughes kit is $89 I am diong the same thing with my 360. It is a pretty straight forward fix.

 

i know how to do a compression test i did one. what im askings is how todo a leak down test

 

Oops

A leak test is done almost the same way but instead of a compression gauge you use a pressure gauge. Not to sound too "mr obvious" but you will need a compressor also. This test WILL be done by manually turning the engine. Performing this test one cylinder at a time at top dead center. A 5-10 percent leak is acceptable at 80 to 90 PSI. If you hear air then you have a fault, tailpipe is exhaust valve/ throttle body is intake valve/ PVC is rings or wall

 

thank u. i will do that test give an update once that is done, but going to order the hughes plenum tonight

 

I recently did a compression test also numbers were simular but I only had 70 on cylinder 6&8 I had just done the Hughes plenum plate I figured the gasket was gone for a while sucked plenty of oil into the intake, if you read the dodge tsb on the plenum fix they say to run combustion chamber cleaner through it because of the oil build up on valves. The seafoam is basically the same thing I just ran it through mine I picked up 20 psi on 7 of the cylinders and the other cylinder that was a 70 is now 150 seafoam does work