[w72]

After some years of mainly waiting on parts to materialize, my project has finally barked to life. No miles yet, but it idles fine and revs like it has an outstanding warrant. 400/467 stroker, 9.7:1, 041 cam, pretty much a fuel injected Jim Hand clone.

I'm almost sure we made a mistake by installing a sheetmetal valley pan. When I bought all the hard parts years ago, I was leaning towards a roller cam and the Tomohawk valley pan didn't exist yet, so the unbaffled valley cover was the only solution I was aware of. Now I realize it's likely going to suck a ton of oil, foul up the O2 sensor and spark plugs, and generally not work for my combo.

Would you take everything apart and swap a Tomohawk pan in, or hack up a catch can solution? Not totally opposed to a vacuum pump situation, but it seems like overkill for a hot street car and I'm not sure how feasible it is while retaining power steering and A/C in an already cramped F-body.

Any help or advise is welcome. Bonus points if you can confirm or deny that the (well respected) builder is crazy for recommending straight 30wt oil.

[Formulajones]

Personally I'd put the baffled pcv pan on. It's not a bad job to do in the car.
A vacuum pump would be overkill on such a mild build and frankly take up even more real estate than the ac already does, not to mention, The bracketry may not work with ac in place anyway.

[i82much]

Maybe just block it and run a PCV valve in one of the valve covers?

[Half-Inch Stud]

I have it 2nd-hand from the PMD designers, that the 2-Ply Valley cover was design- intended to condense the crankcase vapors before exiting the PCV valve.

[grivera]

As Mike and Larry mentioned, pretty easy to swap a valley pan. The hardest part is deciding to do it. If the water crossover is separated you can do it without draining coolant. Of note, the Tomahawk pan may require trimming where it meets intake.

[78w72]

Originally Posted by w72

After some years of mainly waiting on parts to materialize, my project has finally barked to life. No miles yet, but it idles fine and revs like it has an outstanding warrant. 400/467 stroker, 9.7:1, 041 cam, pretty much a fuel injected Jim Hand clone.

I'm almost sure we made a mistake by installing a sheetmetal valley pan. When I bought all the hard parts years ago, I was leaning towards a roller cam and the Tomohawk valley pan didn't exist yet, so the unbaffled valley cover was the only solution I was aware of. Now I realize it's likely going to suck a ton of oil, foul up the O2 sensor and spark plugs, and generally not work for my combo.

Would you take everything apart and swap a Tomohawk pan in, or hack up a catch can solution? Not totally opposed to a vacuum pump situation, but it seems like overkill for a hot street car and I'm not sure how feasible it is while retaining power steering and A/C in an already cramped F-body.

Any help or advise is welcome. Bonus points if you can confirm or deny that the (well respected) builder is crazy for recommending straight 30wt oil.

I would use a PCV pan for street use. As mentioned put the factory pan back on, pretty easy swap on a pontiac, just need to drain the radiator about half way to get coolant low enough to pull the intake without any leaking, buy a felpro pan gasket with ultrablack RTV or just RTV that some use.

Also if you werent aware & decide to go HYD roller in the future, the early non EGR vally pans will work for most roller cams, might require slight denting on the underside for larger cams, was told of that option by Ken, the guy that first made the tomahawk pan.

As for the oil, you will get a lot of opinions on that, but the fact is if this engine is built with tighter street clearances there is no benefit to using a straight 30w oil or super thick race type oils. These engines called for 10/30 oil and if you have good pressure with that oil that is whats best to run, especially if youre in a colder climate & drive in early spring or late fall when cold the oil is thicker and needs to flow as fast as possible at start up. If 10/30 provides good hot idle psi around 20-30 I would run that weight of whatever brand you prefer.

[Skip Fix]

I have only had one sheetmetal valley pan that did not suck oil. I think it was a KRE only had 3 holes and I used a baffled grommet. The Butler has about 15 holes and I "fogged mosquitos" with every king of baffled grommet, mesh in the line. A 2" tall extension. In fact one test drive of course there was a DPS officer who pulled me over. Let me off when I explained what I was doing.

My tomahawk factory style had to have some serious massaging in the corners to fit

[Kenth]

1973-74 Pontiac 455 Super Duty has the PCV-valve located in the drivers side valve cover. Simple and works from factory.

[65madgoat]

Originally Posted by Kenth

1973-74 Pontiac 455 Super Duty has the PCV-valve located in the drivers side valve cover. Simple and works from factory.

Exactly what I run and best bet I feel! Especially if keeping stock valve covers. Simple. Clean. No oil sucking. Can always add a catch can in line if needed.

Get your oil cap here:

https://www.tachrev.com/SDOilCap.htm

[Skip Fix]

Some valve covers don;t have a baffle in the valve cover and I would worry they would suck oil without one.

[w72]

I'm not sure if the original W-72 valve covers are baffled, or if there would be space to add one with 1.65:1 Crower stainless rockers.

[mgarblik]

Originally Posted by 65madgoat

Exactly what I run and best bet I feel! Especially if keeping stock valve covers. Simple. Clean. No oil sucking. Can always add a catch can in line if needed.

Get your oil cap here:

https://www.tachrev.com/SDOilCap.htm

The guy in the link has been out of those SD replica PCV systems for some time and has no plans to make any more. They were pretty pricey as well. I am considering making a production run of something similar with a good friend of mine, but nothing concrete yet. It's way more complicated than it looks, once you get into it. Probably be a year or so before we have something to sell. That probably won't help you.

[VCho455]

Try the PVC in the valve cover to start and if you're not satisfied then do the valley pan. Remember almost every Chevrolet V8 in the 60's, 70's, and 80's had the PVC in the valve cover.

[Schurkey]

Originally Posted by VCho455

Try the PVC in the valve cover to start and if you're not satisfied then do the valley pan. Remember almost every Chevrolet V8 in the 60's, 70's, and 80's had the PVC in the valve cover.

Yeah, the late '60s and onward, but they all had decent baffles welded to the inside of the valve cover to separate and drain the oil mist. They also had the fresh-air inlet on the opposite valve cover, so the fresh air came in at the "diagonal corner" of the engine.

An unbaffled PCV can suck an enormous amount of oil, depending somewhat on where the valve is placed.

[b-man]

Put in the proper factory or aftermarket replacement pan that’s already engineered for the job and be done with it.

[mgarblik]

Originally Posted by b-man

Put in the proper factory or aftermarket replacement pan that’s already engineered for the job and be done with it.

That's what I would do. The factory PCV set-up front or rear worked very well. You can change that pan in 2-3 hours taking your time and checking the fit carefully. Rigging up a "Chevy system" by the time you fab and weld up a nice baffle will take just as long or longer.

[VCho455]

Originally Posted by Schurkey

Yeah, the late '60s and onward, but they all had decent baffles welded to the inside of the valve cover to separate and drain the oil mist. They also had the fresh-air inlet on the opposite valve cover, so the fresh air came in at the "diagonal corner" of the engine.

An unbaffled PCV can suck an enormous amount of oil, depending somewhat on where the valve is placed.

Just like these.

https://www.summitracing.com/parts/t...yABEgJIufD_BwE

[w72]

Those look like a magic bullet if you have clearance for huge valve covers. I have a brake booster and A/C bracket that would interfere.

Likely going to bite the bullet and install a Tomohawk valley pan. Wouldn't be the worst thing to take a peek at the pushrods after break in. Thank you all for the replies and advice.

[NeighborsComplaint]

Originally Posted by Skip Fix

Some valve covers don;t have a baffle in the valve cover and I would worry they would suck oil without one.

Use a baffled PCV grommet and PCV valve in the valve cover.



If you're stuck on pulling the intake, I've never found it much of a challenge and no need for a separated crossover.

Pinch the upper rad hose close to the water neck, remove it from the water neck and secure the end higher than the rad outlet. Remove any coolant from above the Tstat in the water neck using a bulb-style battery filler and remove the water neck. Use the bulb battery filler to siphon the coolant from the crossover and remove the intake.

No spillage and will just cost you a new Tstat gasket.

[w72]

Pulling the intake will be a bit more time consuming thanks to the FI system and its associated wiring. However, the very end of a long project seems like the wrong place to cut corners. I can't wait to drive it!