XS, you sure the air is pushing through the head and out the exhaust? The only reason for that would be:

a) Valves not seating
b) valves are in overlap in the stationary position

There are no other explanations that I know of. I've never seen it happen though. I always test from the compressor and leave everything but the intake connected. This tests the entire pressure system, BOV, IM, head, pipes, BC, everything.

The only think I'd suggest trying is bumping the engine over and trying to test with the crank in a slightly different position.

Oh, what method are you using to pressurize the system? Air tank? Shop compressor?

 

im in panama city FL i wont have the evo for too much longer

 

TB, IIRC, there isn't a position in our motor where all valves are seated at once, correct? if so, then there would always be air in the exhaust.

 

Only one set has to be seated to seal the head ... it should only leak a notable amount if a cylinder is in overlap with both sets of valves open. That would only happen for a brief moment at the end of the exhaust/beginning of intake stroke, depending on cam selection and cam gear/MIVEC settings.

 

ah, I'm with you.

 

so when I'm doing the leak test, should the motor be at TDC?? or what position should it be in?>

 

Both occasions that I've tried to do the boost leak test I have used a shop compressor. I've tried bumping the starter several times. I walked around to the tail pipe while a helper was trying to charge the system and I could hear air coming out. I can not hear any leaks in the engine bay over the sound of air going into the valve steam. If I can borrow or buy a compression tester I guess I can check that next.

 

If you had low compression the air wouldn't come out of the exhaust.

Honestly, I think you lack pressure to fill the system. I haven't had much luck doing tests without at least 80 psi ready to go in a tank. I use a small 5 gal portable tank for this, but any large shop will have a 100 gal+ tank with plenty of pressure to spare. If you are trying to pressurize while a compressor is running with no existing pressure, that will not work.

 

I did this with two different compressors both at over 100psi fully pressurized. I know it wouldn't go out the exhaust it would be blowing past the rings and out the breather on the valve cover... I guess the S1's have alot of overlap.

 

is anyone going to be in boaz tonight

 

or Huntsville

 

im always in huntsville haha! what was going on?!

 

Interesting. I think the samething is happening to me.

 

Im in Huntsville too

 

^^ ive seen you around a couple times... waved but you never waved back!



and if you need someone to put in that clutch let me know! i own a transmission shop ill make you a deal!!