meyer30

iTrader: (2)

I have the HSR, and with all of the little problems I've had putting everything back in the car I still have yet to really tune or test it. But I'm just about there. But before I do that I was wondering if there is a way to tell if it is leaking oil into the intake ports due to it not sealing properly? My heads are 1206 and the HSR is of course 1205. I just bought this but it did not have extra material welded around the ears already. Before I put the plenum on I was able to look down at the ports and everything seemed to be sealing, but how can I tell for sure? I've only ran it for a few short minutes at a time trying to get it to idle and I don't want to ruin these heads...again! So what type of test can I do or a tell, tell sign...Thanks

Supervisor42

I'm assuming you're talking about a vacuum leak at the bottom of the gaskets pulling air from the lifter galley, right?
Do you have access to compressed air?

meyer30

iTrader: (2)

That is correct, and yes I do have an air compressor

Supervisor42

You can test it for leaks using smoke. It's ghetto but it works. You'll need about a foot of 5/8" heater hose, some 3/8" hose and a cigarette (preferably Marlboro red).
Cover the air intake of the throttle body with plastic (large ziploc) and tywrap/tape in place tightly.
Plug off every vacuum lines coming off of the plenum, except the one that goes to the PCV valve which you will remove.
Connect one piece of 3/8" hose where the pcv hose was.
Connect another piece of 3/8" hose inside the 1 foot of 5/8" hose and to the end of the air blower nozzle.
Remove the pcv valve from one valve cover and the pcv filter from the other.
Light the marlboro good and put it filter first into the hose connected to the plenum.
Slide the 5/8" hose over the 3/8" hose with the lit cig.
This limits the pressure that we will put on the plenum.
Slowly blow air (now smoke) into the plenum and watch to see if it comes out of the pcv openings of each valve cover.
Smoke will come out of the plastic to let you know it's working. There won't be enough leakage past the piston rings to matter. If the engine happens to be spotted with both the intake and exhaust slightly open on one cylinder, smoke will come out of the exhaust. If it does turn the crank 10 degrees.
Bizarre huh?

meyer30

iTrader: (2)

Very interesting, thanks for the method. Is there any other way to do this test just in case I don't have a cig handy?

meyer30

iTrader: (2)

I'm running the XFI 268 compcam, how much vacuum should I be getting at idle. I put the gauge on it and it reads about 13.5 in/hg I rev it up and the number drops to zero and then back up. Is this number too low or just about right?

Supervisor42

I don't know what that cam will run in way of vacuum. It's going to be hard to pin down because the timing affects the vacuum so much and of course, the ECM is constantly changing it.
If that weren't enough, the IAC (idle air control) will just close a little more if there is a vacuum leak. Unless there is a vacuum leak so big that it suppplies more air than the engine needs to idle, the IAC will "hide" it.
BTW, when you said "ruin the heads again", what were you talking about? I'm not aware that a vacuum leak (with oil) can ruin the heads on an EFI engine.

meyer30

iTrader: (2)

Well when I first did this motor oil was leaking into the heads thru the lifter valley, apparently the intake did not seal very well due to alot of other things and when I tore it apart the heads were really nasty and needed to be cleaned, so no they weren't ruined but I wouldn't put them back on the motor that way and ended up spending money to have them cleaned.