I have a ProCharged 383 Stroker engine in my 88 GTA and since putting it in the car and running it I cant get the valve covers to seal properly.

It only seems to leak at the back of the heads and mostly on the drivers side.

I have tried using Mr Gasket cork gaskets as I saw people said they were good but I have had no luck.

My heads are perimeter bolt style

Any help would be greatly appreciated

 

over tightening, or not tightening gradually in a criss cross fashion and until reaching correct torque? If they call for 20 ft lbs, I 'll usually go around the horn, starting with 10, then 15 and then finally 20 so that everything has a chance to seal evenly. or maybe something is bent?

 

btw - what kind of shock tower brace you running there? is it one side or both?

 

probably inlbs 20ftlbs sounds like a bolt would break the vc

 

ya, poor choice of a number, but used it to get the point across.

 

I suppose you could find an object that is truly flat, and check for warpage on the head surface and valve cover gasket surface. I have had success with Fel Pro silicone valve cover gaskets, but I have centerbolt heads so I have some advantages there. Gradually tightening opposing sides is the way to go, I would just do it by feel with a nut driver unless you have a high quality in. lbs. torque wrench.

 

The bolts are supposed to be only "snug". Tightening more will just make them leak worse. Do you have the load spreader pieces that each bolt goes through (4 per cover)? Those are important for preventing warpage. I never use cork gaskets for those. I always use rubber gaskets, and glue them to the covers (not the heads) with RTV with good results...

 

If you are using a chevrolet PCV valve attached to the intake manifold it will leak under boost and force oil out from the back of the valve cover (ask me how I know)
Solution is use a high quality toyota supra twin turbo pcv valve.

although I Dont see any pcv valve in the pictures just throwing this out there

 

They are home made and are on both sides

 

covers and gaskets never came with load spreads as was told they are not needed. I used to use rubber gaskets but everyone recommended cork so thought I would try it. I used and always use RTV

 

I have PCV valves that I got off of Summit racing but removed the valves so straight through breathers now

 

My '83 came with the load spreaders, so they're necessary (UNLESS you have after-market cast aluminum covers with a thick flange). Cork gaskets are 100 year-old technology. Why anyone use them in the 21st century is "mind bottling"...

 

Just so you understand by using a breather you are forcing crankcase pressure to rise above atmospheric, it will try to fill the crankcase like a balloon, which will force oil into every seal and causing oil leaking.

I am not saying this is the cause of your leaks; The seals should be able to take some small amount of pressure from crankcase blow-by. However in the long run it will eventually leak from every seal without a proper PCV system, because time + pressure = leaking. A proper PCV system pulls pressure down below atmospheric, into a vacuum, which will pull oil OUT of engine seals, prevent leaking. It also protects oil quality making the oil cleaner and reduce engine deposits in the circulatory system. Something to think about

 

there is no vacuum to reduce crankcase below atmospheric as the engine is supercharged. so inlet to pcv has to be plugged and routed to oil catch can. otherwise supercharger will boost into crankcase stopping excess pressure escaping

 

Sorry you are new to forced induction. There is always vacuum available.
https://www.supraforums.com/threads/.../post-13980010
At part throttle it comes from the pcv valve -> Intake manifold. Use a supra Twin turbo 95-98 PCV valve, not chevrolet. Chevy will leak.
During boost it comes from the air filter tract. Behind air filter is a vacuum for PCV.

I set up hundreds of turbo and supercharged engines using factory PCV. How do you think I learned to do it properly? By simply investigating OEM factory turbo and supercharge setups

 

felpro race gaskets with sleeves to help prevent overtightening, and a quality valve cover should seal it. if blow by is causing it look into some sort of crankcase vacuum pump.

 

hehe "some kind of vacuum pump" the engine is an effective vacuum pump. It does tend to move air.
So are turbochargers.

 

if you do not know what i am refferring to when i said vacuum pump I cant help you my friend. crankcase evacuation vacuum pump was the implied meaning, sorry I assumed most here were car guys, and since we are talking about a power adder engine it is also implied that crankcase pressure is a known issue with power adder cars etc. guess you are unfamiliar with the concept, or commonly used moroso, gz, and other Vacuum pumps used to deal with this sort of thing.

 

Sometimes the cork doesnt line up well with the head flange and or the valve cover flange. Same problem on my bbc if i dont line it up right and tighten it down correctly. Looking at the gasket you can see on the imprint of the cork where it lies on the head and cover. Could try the blue rubber coated steel laminate style felpro gaskets. Or you could glue the cork to the head with rtv so bottom half is sealed and doesnt move when putting covers on, so no misalignment happens.

 

I use vacuum pumps and dry sump systems with many engines. What I was referring to is the fact that the engine itself is an air pump, it is a vacuum pump. You can use the vacuum pump action of the engine piston to drive the PCV system. You can also use a turbocharger the same way- to provide kinetic energy to the PCV system which drives crankcase evacuation.

At wide open throttle there is a pressure drop behind the air filter. This pressure drop is utilized in ALL factory vehicle gasoline engines to drive PCV action at wide open throttle, using the engine as the vacuum pump to drive a pressure below atmospheric inside the engine crankcase. Exactly like an externally driven vacuum pump would do.

THe reason we don't want an external vacuum pump on some engines is because of the increased complexity and maintenance related issues. They are not street friendly due to maintenance concerns and additional parts complexity.

Crankcase evacuation using air filter pressure drop example

 

Or maybe you prefer to suck it into the intake tract and use that as a source of vacuum? It is far more common with high performance power adder v8 stuff to use a belt driven external vacuum pump, or electric vacuum pumps and keep it from heating or potentially contaminating the air fuel charge. more than one way to skin a cat I guess

 

Weeeeel Intake manifold doesn't have significant vacuum at wide open throttle due to rapid pressure variations as valves open and close. Perhaps you have heard of water hammer? Engineering textbook phenomenon where pressure waves reflecting from closed valves travel up into the plenum...

The pressure drop is produced in front of the throttle valve, this is where OEM engines 100% of original engines receive their PCV signal for wide open throttle, using the engine as a vacuum pump.



In forced induction engines the same thing happens but instead of the throttle valve, it happens at the compressor wheel inlet or supercharger inlet, the region behind the air filter.

All factory engines use the engine as a vacuum pump to drive PCV. It is when people disable this system and have no idea how to use the OEM pcv system which starts causing oil leaks.
The pressure rises in the crankcase without proper OEM pcv and causes oil leaking, and other issues such as carbon deposits, reduced oil quality, long term health issues with the engine, reduced piston ring function, many issues as a result of disabling or removing the OEM pcv system setup.

 

Good idea using the electric vacuum pump to drive crankcase evacuation. It is often easier to do with small displacement engines.
For example here is 2L engine at 500rwhp in an evolution using the electric vacuum pump to drive PCV.

Here is an example of somebody using electric pump for PCV in crankcase pressure monitoring and control

https://www.evolutionm.net/forums/ev...l#post11930508



I hope this example helps put PCV into perspective. You must control the pressure somehow, electric pump, belt driven, exhaust driven, turbo driven, find some way to achieve the goal of low pressure in the crankcase. The OEM uses the engine as a vacuum pump but as our friend here pointed out, 'many ways to skin a cat' The main thing to realize is, the crankcase pressure must be MONITORED and CONTROLLED. You can't just ignore it and pretend like it doesn't exist. That is like installing a fuel pressure regulator and then not checking the fuel pressure. Crazy!!!

 

for years now gz motorsports has made a very good sportsman kit that they stand behind when used on the street, is a bit pricy, but it is a complete kit several 3rd gen fbody people have used it. still others have used the electric smog pumps from cobra mustangs, the trick with them it seems is setting it up to ramp up at wot, and switch down when under light cruise conditions. if you run them at a 100% duty cycle they do not last long at all. back to the gz kit, it is a modified gm smog pump they have machined and fit vanves to, as well as a regulator setup. the nice thing about them is they can bolt right up using the oe serpentine belt routing etc. but a little pricy.

 

with afr heads, and allstar fabricated valve covers this works great! there is no slop in the bolt holes i used a dab of rtv to make the gasket stick to the valve cover i have had it off 3 times now, very easy to bolt back up, doesnt allow overtorque or crushing of the gasket. not sure what to say for you centerbolt guys, for perimeter bolt covers it works awesome. the gaskets were $45 a couple years ago, but barring damage when removed they should last forever, no contact with pushrods like the cork and rubber laminated steel shim gaskets i used prior had. the gasket is a good guide for mockup too, clearance the heads where the gasket has notches and you wont have pushrods rubbing the heads. thats with 1.6/1,6 shaft rockers and a .576/.576 lift cam. plus they are big enough that installing baffles for pcv and breather is easy, and no clearance issues with the c4 wiper motor. so third gen guys should be fine with this setup too. 100 for valve covers, 45 gaskets and it killed a few birds with one stone. i was able to bolt the wire seperators to it too. for my na 383 i just used a fixed orfice pcv valve, and the stock l98 breather hose and fittings with a pair of parts store grommits. ill have to get a photo to show you guys, it is a tidy setup, looks good easy to remove and service