76Supreme350

Hello. I have a 1976 Cutlass with a 350. I am putting in 1.6 roller rockers, performer rpm intake, and a holley 700. I was figuring while doing that I should replace the head gasket because its my daily driver. Also, while the heads were off I figured I should go get them ported with the extra parts going on. I found another set of heads off of a (i believe to be) 1970 cutlass in a junkyard nearby. They want 100 for both heads. My first question, should I get them so that way my car wont be out of commission for longer than a day. Also, when I get them ported and polished should I also get it cut to raise compression ratio or will I run into valve clearance. And last, should I get the valve enlarged and are there even any larger valves available, or is it possible. Thanks.

captjim

First off, going with older 350 heads will raise the Cr quite a bit as the chambers will be 15 cc +/- smaller. So yes, get the older heads, have larger intake valves installed and spend the extra money on a little bowl work. No need to have the ports worked on or polished, IMO.

While you have the intake off, and to take advantage of the compression ratio increase, I would definitely upgrade the cam and chain, you are already half way there. Something like the 60801 Voodoo, 16-18 Engle, or as always get Mark to grind you one. Something in the .480208 @ .050 neighborhood. Your Cr should be around 8.6 to 1.

Warhead

Sounds like a good plan.
Not doing the valve job/guides is like throwing power away. 20-50 hp in some cases.
$100 is a good price for those heads. Get larger intake valves installed (good power for $, unlike the exhaust side), 1.875 is stock, a 2 inch intake is a good move up, along with a bowl clean-up. Have them do a 30 degree back cut on the intake valve, while they are at it.

I would keep the cut to around .030" max, but you will not have to worry about valve clearance at these lifts.
Good luck,
Jim

76Supreme350

Hows this? http://www.jegs.com/i/Lunati/638/00083LK/10002/-1

captjim

Waaaaaaaaay too big.

88 coupe

Is cutlassefi claiming to be a cam grinder?

Norm

captjim

I don't know what he claims to be, ask him. I do know that he has helped several fellas on here with their camshaft selection and purchase.

76Supreme350

Ok, I got the heads and the valve job is going to run 600 with bigger valves included. Is this about as low as I can get? Someone else said 700.

Warhead

There is always a way to spend more, $600 for this with the bigger valves going in is a good price.
Are they doing guides, and new valve springs?

Jim

citcapp

Nope, but he can get you a heck of a good deal on a cams, lifters, and he has the knowledge to help you select a cam if you give him the correct information on your engine build, transmission, convertor, rear end, etc. quality american made parts too. I shopped around quite a bit before I bought my cam and roller lifters. I also checked him out with other guys who used his services and did not find any compliants.

captjim

Classicolds resident troll Norm has made 2 posts in SBO tech forum. The one in this thread,
"Is cutlassefi claiming to be a cam grinder?"

And this in the "suggestions for build" thread,
"Without a precise definition of "unstreetable" your arguments are worthless."

Both are argumentative and add zero info, experience, or perspective to either thread, yet he constantly chastises others for doing the same thing, and the moderators here allow him to do so. Mark has done nothing but help guys, Norm does nothing but criticize and argue. Same old story.

cutlassefi

Thank you Jim and Pat. I try to help as you said, I've been in a position where some nitwit like Norm gave advice straight from a book, not from experience, and it wasn't worth a darn.

I'm not perfect, but I try to offer real world facts that I've experienced over the years. Norm doesn't have a clue.

Here's Panos' dyno sheet from monday. In case you don't know the specs they are;

10.85:1
Erson Hyd Roller 238/246 on a 110 in at 105.
Out of the box Performer with just the center divider cut
Out of the box Quick Fuel 830
C heads with 4 angle valve job with crossovers filled and center divider welded, otherwise bone stock

https://classicoldsmobile.com/forums...ess-455-a.html

76Supreme, I'd be happy to help. Email me anytime.

380 Racer

clapsmiley.gif clapsmiley.gif clapsmiley.gif

380 Racer

By the way Norm, thank you for using a quote from me in your signature. Shows how you can take something not only out of context but also alter it at the same time. Sheesh......get a life!

67 Cutlass Freak

This engine from the factory had 79cc heads with low compression deep dish pistons. I believe 8.5:1. The '72 had 69cc heads. That would increase your CR some but most likely not more than 1/2 a point. You could & should mill some without any valve to piston clearance issues. What are your goals? How much money, I mean how fast do you want to go?

Pocket porting is good. Bowl enlargement is the only way you can fully take advantage of larger valves. Filling the heat risers & welding the exhaust dividers is also a good idea. Enlarging the ports themselves is very time consuming. If you are going to port yourself do your research. I've ported a few sets. Each set takes me about 80 hours. I do not have a CNC. More flow is not always the answer. For more torque smaller ports yield higher velocity.

Offer them $200 for the complete long block. Build a completely different performance engine. Beef up the bottom end. Get some higher compression pistons. Maybe a halo, some light weight rotating components. Maybe consider a stroker with Chevy rods. You should know what cam and lifters your going to use to select the correct valve springs.
Here's some photos comparing a set of ported BB heads to unported #4 castings off a 1967 330 with 64cc combustion chambers. It's really hard to get good photos of the runners with a my digital POS camera.






If you are considering porting the heads yourself you should check out these two tech articles -

http://www.mondellotwister.com/ArtHeadPort.htm
http://www.mondellotwister.com/ArtPtngAtHme.htm

I know everyone has a very negative opinion of the big "M", but Joe is a great guy and has made huge contributions to the Olds community. Please don't get me started about Lynn.

88 coupe

Here it is again:

If the suggestion is followed and Mark grinds a cam, wouldn't it make him a cam grinder?

Considering the statement, how is the question not legitimate?


Thanks. I will assume that captjim simply misspoke and, as he has in the past, launched a personal attack, in order to divert attention from it.

On the outside chance that anyone might like to view the original posts, simply click those two blue buttons in my sig.

Considering the content and lack of maturity, shown in the last four posts, I find it interesting that captjim is the one who complains about the lack of moderation.

Norm

captjim

Norm, you are hysterical!!

67 Cutlass freak, on a standard bore/stroke 350, the compression ratio difference between 79cc and 69cc is .73

Also, aren't most #8 heads more like 80+ where some 350 heads are 68 or less? That WOULD make the change almost a point.

67 Cutlass Freak

captjim wrote-
Wow Jim I'm impressed. Good math skills. I just plugged in the numbers & came up with a .7 increase from a 10cc chamber difference also. Maybe I was thinking of a BB where 10cc's won't gain that much. I just checked the reference manual and for 1970 the Olds 350 came with a 70cc combustion chamber. All #8 heads were listed as 79cc.

380 Racer

So Norm, just take anything about me out of your sig line as it was taken out of context of that whole thread. Got that *uckstick?

captjim

No math skills here, my brother, ONLINE CALCULATORS!
http://www.angelfire.com/fl/procrastination/motor.html

I have measured quite a few older 350 heads, and yes most come in around 68-69 cc. I have not measured many (if any???) # 8 heads, so I have no idea how accurate the published data is.
Also, depending on what head gasket is used on the engine, he might even pick up another .15 by going to a .028

76Supreme350

Jeeze, I don't check for a day and there is a war going on, lol.

The heads are from a 70, not a 72. The machine shop guy told me they were around 64cc. I'm not looking for a super fast car. I'm building a sbc for my 80 LeMans that is getting all the high performance. I just wanted to add an intake, carb and rockers, but figured a gasket change and those heads would help some. I will probably just get the valve job done and leave it at that.

88 coupe

If you have an objection to my sig, send me the details in a PM. If you can show that your complaint is valid, I will be happy to replace it with an apology.

Norm

geckonz08

67 Cutlass freak ---I can see where the 80 hrs come from/go to.
Those heads look preeemo .
How do they flow ?notice the difference ??
mike