[moontower69]

Previous owner rebuilt the 350 30 over with 4X small vale 96 heads - but can't for life of me understand WHY they put this peanut cam #537441 grind in it....had decent torque off idle but nosed over at 2600 rpm....and 4 barrel was worthless...hence this swap.

Got the Butler 067 to swap out and hoping for more top end. Anyone been here before, any advice? With 7.6 compression, I'm thinking 067 is about as big as it can handle.

It's as father son project.

[moontower69]

Car is a 1974 Lemans GT...

[steve25]

The last time the 067 cam was used in a 4-bbl 350 was in 69 with near 10 to 1 compression.

Your original cam had a advertised duration of 269/277 with 51 degrees of overlap..

With your 7.6 compression and if you do not have 3.55 rear gears then if you wanted to run a factory cam I then I would run the 066 cam along with 1,65 rockers.

The added .040” lift will help to add much needed torque besides some top end power.

The advertised duration of the 066 is 273/282 with 55 degrees of overlap.

You really need to mill those a heads atleast .045” which will knock 7.5 CCs out.

If you really want to run the 067 cam I would mill your 4X heads .060” on the deck and intake flange so everything bolts up well.

Be sure to replace the valve springs either way because 50 year old springs will not cut it .

[b-man]

I know you already bought the cam but I would have chosen the 066 factory piece instead.

The 066 was used in the 1968 350 HO auto trans cars.

[jhein]

If the 067 is still NIB, you can probably exchange it. I bought a cam from Butler and changed my mind and they swapped it for me. It did cost me shipping but I got the cam I wanted.

[Tim Corcoran]

Originally Posted by steve25

The last time the 067 cam was used in a 4-bbl 350 was in 69 with near 10 to 1 compression.

Your original cam had a advertised duration of 269/277 with 51 degrees of overlap..

With your 7.6 compression and if you do not have 3.55 rear gears then if you wanted to run a factory cam I then I would run the 066 cam along with 1,65 rockers.

The added .040” lift will help to add much needed torque besides some top end power.

The advertised duration of the 066 is 273/282 with 55 degrees of overlap.

You really need to mill those a heads atleast .045” which will knock 7.5 CCs out.

If you really want to run the 067 cam I would mill your 4X heads .060” on the deck and intake flange so everything bolts up well.

Be sure to replace the valve springs either way because 50 year old springs will not cut it .

This is good advice your compression is way low for any kind of performance. If you mill the heads make sure to also mill the intake side an equal amount or the intake manifold won't set right. And yes, new valve springs, lifters and maybe pushrods too. At least check the geometry. Don't use just any lifter, get the Hy-Lift Johnson lifters Butler sells them. And you will need to have a way
to adjust the lifters so you will need some poly locks too. If you don't you will have major problems.

[b-man]

This looks like a simple cam swap, as much as bumping the compression a bit makes sense I’m guessing they’re not planning on spending a considerable amount on machine work to accomplish that.

The best and most economical route to take is to choose a smaller cam than whatever the Butler 067 cam specs turn out to be.

The factory offered the 066 cam in some of their 7.6:1 400 engines (1976 T/A auto trans with 2.41 rear being one) so it should work fine in a low compression 4-barrel 350.

[kyle_blake]

Not sure if you are interested but the engine i just took apart 428 ,had a way to small cam in it. I kept all lifters in order and the cam looks in excellent condition. I'm up in Canada though and I'm sure you have more options closer to you. exchange cam as someone suggested.

let me know if interested. i attached the spec of cam , it was made by CRANE.

[moontower69]

Ok, thanks for the advice. I think swapping heads now as well is in order! Thinking since the rest of the motor is in great shape (no blow by and doesnt burn oil and great oil PSI of 60 at cold start) and my son is up for the challenge of pulling the old heads.

So to run the Butler 067 (wasn't cheap) I need a small valve head to get to what 8.5 or 9:1?

Saw an old set of #46s bare heads on Facebook marketplace or should I look for #14 or #17?

[moontower69]

Looking at a set of #17 cores on Ebay w small valves, gets this 350 to about 9.3 w 75cc by my calculations, will that work well with my Butler grind 067? I def dont want to go full 068, this has a 3.08 rear and is just a fun around town car, no racing.

Plus my son is 15 and has his eyes on this car....dont want him to have too much power....

[b-man]

Those #17 heads would be a good head swap to get you where you want to be with the cam you bought.

#17, #47 or 1969 #46 400/428 heads are all small valve heads that would bump up your compressor into the right place.

[77 TRASHCAN]

I have a Virgin set of 17 heads I bought, thinking they had smaller chambers. I check both heads, 2 chambers on each head. All were 83.5 cc's.....

[steve25]

By the time you shell out the bucks for another set of heads and then these days pay the crazy rates for shipping 90 lbs of cast iron and also potentially then to have a shop clean them up, and maybe mill them .002” to get them level you might as well just do to the cost factor mill your 4X heads .060” on the deck & flange and cam for that compression that you will end up with.

At least then you will have the 4X heads hardened exh seats that is needed for unleaded fuel.

[moontower69]

I'd be interested in your #17s!

[77 TRASHCAN]

Originally Posted by moontower69

I'd be interested in your #17s!

I responded to your PM

[b-man]

It all comes down to how much money you’re budgeting for this father and son project.

Leaving the original heads on the engine is by far the least expensive route. Either roll the dice on the 067 cam and hope it gives you some decent results or exchange it for the 066 cam. After I checked the Butler 067 I see it still has a low lift of .405” like a factory cam and pretty reasonable duration for a low compression engine, it’s not a bad match.

Shipping a pair of Pontiac heads is ridiculously expensive now, the last set I shipped from CA to FL was $275 for the pair, that was with me doing all the packaging myself at no charge to the customer. The heads sold for $900 so the customer was able to justify the shipping cost. Each head packed up was around 65 pounds 22x10x8 wrapped in about 4 layers of heavy cardboard with a very generous amount of packing tape securing it.

Then once you send the heads to a machine shop and rebuild them you’re looking at $500 for a substandard rebuild keeping the old valves and knurling the guides and probably reusing the old valve springs all the way to $1500 to do everything right with all new parts and touching all the bases.

Is it really worth swapping and rebuilding some different heads to bump the compression 1 or 1-1/2 points just to use the cam you perhaps bought in error, or would it be more in line with the aim of this project to simply buy a cam that’s more compatible with the 7:6:1 compression engine you already have.

Only you can decide. If you’re not into sending your newly licensed son down the road in a powerful car then maybe going for the less expensive and easier option may serve you best. Replacing a worn out cam and lifters along with the timing set makes perfect sense on an otherwise sound long block, beyond that again only you can decide.

Good luck with your project.

[PunchT37]

I don`t think this Butler "067" cam is nearly the same as factory. Looks like it`s got way shorter seat timing than factory.


I say, run it. Could get away with factory springs IF they check out.

[PunchT37]

Originally Posted by PunchT37

I don`t think this Butler "067" cam is nearly the same as factory. Looks like it`s got way shorter seat timing than factory.


I say, run it. Could get away with factory springs IF they check out.

My bad. Unless you got the melling version. You might be able to exchange for the "Ram Air Series" with it`s shorter timing and stock type lift.

[Singleton]

Cam card for the Butler 067. The factory 067 had 273/289 advertised duration and 114LSA with 53* overlap.
Butler 067 has 27* overlap.
Butler cam is closer to the factory 066 than it is to the 067. 066 has 273/282, 200/210@.050, .410/.410 lift, 111LSA, 55*OL

[moontower69]

I got a pair of #17 small valve heads ready to install (and gone over) off Craiglist and am going with a Cometic .27 thickness head gasket (since the heads are I think only about 84 cc's).

Should give me close to 9:1 and run strong with 067 and 3.08 open gears or am I missing something? (The rest of the 354rotating assembly was rebuilt by prior owner w 60 PSI oil pump and good compression and doesnt burn any oil or blow by etc.)

Just want it to make decent power to 4000 rpm, the stock replacement #537441 was pretty much an 066 and grunted strong off idle to 2400rpm and then nosed over....just want to improve on that (perhaps it was worn valve springs holding the old cam back?). Have stock converter and peg leg.