[cttempest]

Good or bad idea?
I was running this setup on my car for years a long time ago.Everything seemed to work good,and car had nice power.
Now my shortblock is in machine shop and almost ready,but I'm not sure if I should stick with theese heads or go to with something with 1.96/1.66 valves.

I need to figure this out so I can pick a cam and a tourque converter for the th-350(I'm thinking 2400 stall)? and so on.Any help is appreciated.

engine:
1972 350 YU bored .030,sealed power pistons,stock crank and rods.I do not belive it has been decked at all.
heads:
1967 326 140 casting.1.94/1.64 valves 9.2cr..Not sure if they have been milled but have had valve work done by whoever built the motor.Has screw in studs now and was running Comp Cams magnum 1.52 roller tip rockers and I belive an 068 cam.


My plan is to use a Summit 2801 cam.I would like to reuse the rockers.

Yes I know a 400 would be more power and all that,but this motors only temporary while I build a bigger one with forged internals in a few years from now.This motor was in great shape when I tore it down,and needs minimal work,so Im using it,and it'll go in my daily driver once my 400 is done.Any help is aprreciated.

[dmac]

Make sure you cc the heads if you aren't sure. 9.2 cr original on the 3.26could be close to 10:1 or even more if the heads have been milled with the bigger cubic inches of the 350.

If you really have 9.2 with the 350, and are on a budget, those heads will be fine for regular driving. Might want to switch to 1.65 rockers if your current cam and lifters are in god shape. Just have the pushrod holes enlarged. 1.65 rockers will give you almost the same effect as a slightly larger cam. Have the shop verify springs are okay for the added lift.

It really comes down to your budget. Bigger valves wouldn't hurt. But 'stepping up' any component means upgrading everything else or just upgrading that one part is not going to net as much.

[PunchT37]

068 cam was prolly not bad. A lot of lift could be a problem. Not too sure about how much. The 326 had a different valve angle/placement than the 350. Might want to check valve to piston clearance with bigger cams.

[cttempest]

Originally Posted by dmac

Make sure you cc the heads if you aren't sure. 9.2 cr original on the 3.26could be close to 10:1 or even more if the heads have been milled with the bigger cubic inches of the 350.

If you really have 9.2 with the 350, and are on a budget, those heads will be fine for regular driving. Might want to switch to 1.65 rockers if your current cam and lifters are in god shape. Just have the pushrod holes enlarged. 1.65 rockers will give you almost the same effect as a slightly larger cam. Have the shop verify springs are okay for the added lift.

It really comes down to your budget. Bigger valves wouldn't hurt. But 'stepping up' any component means upgrading everything else or just upgrading that one part is not going to net as much.

Well,if I decide to use them,they will definitely get cc'd and gone through.Stronger springs if need be etc.I just didnt want to go through all that if it's a waste of time.I'm kinda on a budget,but would rather sacrafice cash if theese heads would rob horsepower this engine doesn't have.Ha
If were only talking small power gains from sourcing better heads,having them gone through and all that,I may as well stick with theese as they are pretty much good to go and the cc's and springs check out.Like I mentioned,someone installed screw in studs,poly locks,and to be honest,the springs are clean,shiny and black still,which really doesn't mean much,but I think they are newer and stronger

[cttempest]

Originally Posted by PunchT37

068 cam was prolly not bad. A lot of lift could be a problem. Not too sure about how much. The 326 had a different valve angle/placement than the 350. Might want to check valve to piston clearance with bigger cams.

I will definitely be checking that either way.
I was told it was a 068 back when I got engine in 1998.But I cant tell what exactly it is.I really like the Summit 2801.Especially for the price.I dont think I'll be using cam that was in ther because I let it sit in a damp garage and it started to get rusty.

[cttempest]

I should have mentioned I will be using a stock Pontiac intake,not the Torker that was on there

[Formulabruce]

Originally Posted by cttempest

Good or bad idea?
I was running this setup on my car for years a long time ago.Everything seemed to work good,and car had nice power.
Now my shortblock is in machine shop and almost ready,but I'm not sure if I should stick with theese heads or go to with something with 1.96/1.66 valves.

I need to figure this out so I can pick a cam and a tourque converter for the th-350(I'm thinking 2400 stall)? and so on.Any help is appreciated.

engine:
1972 350 YU bored .030,sealed power pistons,stock crank and rods.I do not belive it has been decked at all.
heads:
1967 326 140 casting.1.94/1.64 valves 9.2cr..Not sure if they have been milled but have had valve work done by whoever built the motor.Has screw in studs now and was running Comp Cams magnum 1.52 roller tip rockers and I belive an 068 cam.


My plan is to use a Summit 2801 cam.I would like to reuse the rockers.

Yes I know a 400 would be more power and all that,but this motors only temporary while I build a bigger one with forged internals in a few years from now.This motor was in great shape when I tore it down,and needs minimal work,so Im using it,and it'll go in my daily driver once my 400 is done.Any help is aprreciated.

This is a kick ass set up you have been running, for a 350, I ran the same set up, reliable, and 350HO power.. you already have the screw in studs, keep the cam and the springs,Stock intake too!~ Cc the heads and rock with it.. Dont discount the homework you did before, it was good!!, and reliable.

[cttempest]

Originally Posted by Formulabruce

This is a kick ass set up you have been running, for a 350, I ran the same set up, reliable, and 350HO power.. you already have the screw in studs, keep the cam and the springs,Stock intake too!~ Cc the heads and rock with it.. Dont discount the homework you did before, it was good!!, and reliable.

Really?Well,thats exactly what I wanted to hear!!!
I had this engine in a Tempest wagon,and that car hauled ass.
Anybody I took for a ride was holding on,and very impressed.Thats why I figured it was probaly a good setup,especially with a tight budget.

Like I said,the cam in it started to rust.So do you agree on the 2801 from summit?

[dmac]

I would go 2800 after just seeing what the 2801 is like in a 400. Tire burning with cam, carb, headers at 9:1

Are your heads listed as 9.2: on a 326? Where did you get that number? As others stated, valve clearance and chamber cc is key

2801 will be a lot of cam.

[cttempest]

Originally Posted by dmac

I would go 2800 after just seeing what the 2801 is like in a 400. Tire burning with cam, carb, headers at 9:1

Are your heads listed as 9.2: on a 326? Where did you get that number? As others stated, valve clearance and chamber cc is key

2801 will be a lot of cam.

i'll look into t+he 2800

i found the cr on Wallace racing site

I will definitelt be cc'ing theese heads and checking clearances.

[Formulabruce]

Originally Posted by dmac

I would go 2800 after just seeing what the 2801 is like in a 400. Tire burning with cam, carb, headers at 9:1

Are your heads listed as 9.2: on a 326? Where did you get that number? As others stated, valve clearance and chamber cc is key

2801 will be a lot of cam.

X2!
Also, in STOCK form, a '71 350 with a 2bbl already has 350 ft lbs of Torque!!
edit: Every single Pontiac 350 made was actually a 355 too!! right from the factory!

[dmac]

If those heads were 9.2 on a 326, they are almost 10:1 on a 350, even more on a bored out 350. Even more if they have been milled at all. If you are over 10:1, it would explain the good performance, but you need to watch the octane level in the gas. If you have 93-94 available easily, you might be okay with 10:1

[cttempest]

Originally Posted by Formulabruce

X2!
Also, in STOCK form, a '71 350 with a 2bbl already has 350 ft lbs of Torque!!
edit: Every single Pontiac 350 made was actually a 355 too!! right from the factory!

very true!!!

[cttempest]

Originally Posted by dmac

If those heads were 9.2 on a 326, they are almost 10:1 on a 350, even more on a bored out 350. Even more if they have been milled at all. If you are over 10:1, it would explain the good performance, but you need to watch the octane level in the gas. If you have 93-94 available easily, you might be okay with 10:1

Good points.Well,I definitely dont want to be over 10:1.I don't mind if the cars going to run on 91,but that's max.I'm even having a hard time getting VP around here.The closest station that sold it closed.

[Squidward]

I'll be curious to see how your build goes.

My current 350 build was going to be a 350 H.O.-ish setup with 2801 until I fell under the turbo spell.

I am running the 2800 cam right now in a different 350 motor. I'd say it's a great cruising street cam, fun to romp on. It's faster than a previous 400 with 066 cam. But you may find yourself wanting a little bit more after a while.

I've never ran an 068 before, especially in a 350. But given its wide LSA, might it be a better choice for what sounds like a higher compression setup? Others would know more.

I like seeing people build some of the smaller motors. Strangely enough, I have a spare 350 sitting around, and a 326 with 140 heads.

[cttempest]

Originally Posted by Squidward

I'll be curious to see how your build goes.

My current 350 build was going to be a 350 H.O.-ish setup with 2801 until I fell under the turbo spell.

I am running the 2800 cam right now in a different 350 motor. I'd say it's a great cruising street cam, fun to romp on. It's faster than a previous 400 with 066 cam. But you may find yourself wanting a little bit more after a while.

I've never ran an 068 before, especially in a 350. But given its wide LSA, might it be a better choice for what sounds like a higher compression setup? Others would know more.

I like seeing people build some of the smaller motors. Strangely enough, I have a spare 350 sitting around, and a 326 with 140 heads.

I'll have to look into your turbo build,sounds awesome!!!

Yea after more research and talking with some people,I'm thinking about the Comp cam,it seems the Summit ones arent going to do it for me.

I like the small motors too.My pops had a 350 with a tri power and 4 speed in his 65 Goat way back.That car ran!!!!I grew up riding in that car and still remember the power it had.He won a lot of street races with that setup.

My 350 is in machine shop,I had to get two pistons from Summit.Crank is ground,block is pretty much almost ready.I cant wait!!

I think Im just gonna fire the heads back on the way they were,only thing about motor that will be diffrent is the cam and I'm using a stock intake now.I'll see how she runs and go from there.

[dmac]

You might have gotten away with higher compression with the stock cam. A lot of the comp cams are ground to build cylinder pressure. You might end up with more cylinder pressure. If you are selecting a cam, it is important to know what your cr is now. Just because the old cam worked in the combo doesn;t mean a different cam will.

10:1 cr might work with the stock cam, but you might get a lot of detonation with pump gas with a different cam due to lobe design and timing. To make sure your engine lasts, just get your heads cc'ed. It is really quite easy to do.

[A.W.Dille]

What you're doing sounds similiar to what I'm doing on my 350 but I already have an 068 cam in mine and going to be using 143 heads with a 69 iron intake with a Q-jet and headers. The 7H1's just didn't provide enough compression for the cam. And I have no problem getting 93 octane where I live so hopefully detonation won't be a problem.
I agree with dmac as to cams with a tighter lobe seperation building cylinder pressure, I have that problem with the Lunati that is in my 400 in my GTO, have the timing backed off and still have a detonation issue. Opening the chambers slightly will help by lowering the static compression if you want to use a cam with tighter lobe seperation, which in turn will raise the dynamic compression which would put you on the borderline for detonation but not as likely as if you leave the chambers stock.

[cttempest]

Originally Posted by dmac

You might have gotten away with higher compression with the stock cam. A lot of the comp cams are ground to build cylinder pressure. You might end up with more cylinder pressure. If you are selecting a cam, it is important to know what your cr is now. Just because the old cam worked in the combo doesn;t mean a different cam will.

10:1 cr might work with the stock cam, but you might get a lot of detonation with pump gas with a different cam due to lobe design and timing. To make sure your engine lasts, just get your heads cc'ed. It is really quite easy to do.

Well,change of plans anyway now,read my next post.ha

Good advice on Comp cams.Thanks

[cttempest]

Well,I cc'd the 140 heads today,and if I did everything right(which as simple as it was,I'm pretty sure I did)this is what I came up with


Using ATF
made my own plate out of a CD

I came up with 66cc's

That was with and without cd in place,head perfectly level,clean chamber.I checked a few and they were pretty much all the same.

I'm assuming time to scrap theese heads and go to plan B,which I dont have yet,ha.