I am building a 1976 350 Olds out a of Vista Cruiser. It is all stock just basically freshening it up with new components. I am having difficulty selecting a camshaft as I want somewhat of a lope but also good performance to it as well. If anyone could recommend me a cam or guide me in the right direction it would be much appreciated. (#8 Heads)

-John

 

Your bigger problem is the dismal compression ratio in that motor. Consider spending the money on earlier heads first.

 

The heads are already done and painted so that’s out of the question

 

With low compression you have to stay conservative with the camshaft or it will be "overcammed" and have no low end power and be no fun to drive.

 

There was a new flat tappet 307 Vin 9 cam on Ebay for quite cheap. Basically the same cam as the mid 70's 455. It was a mild upgrade and helped add 30 HP to a 307 over the Vin Y. The generic 204/214 cam also worked well for me in a 76 Olds 350.

 

I was looking at comp cams 42-229-4. Should I bother doing any work to the heads at all to boost hp?

 

That cam should work, but I wouldn't waste the money.

 

what cam should I go with then?

 

You should at least have the heads milled 0.030" to account for the thicker head gaskets that are commonly available now. The factory original head gasket was an embossed steel shim type which would have been about 0.017" compressed and today's replacement head gaskets are mostly composition type and about 0.043" compressed.

 

alright I’ll consider it, any suggestions for the cam?

 

The cam you are looking at, Comp 42-229-4, should work well or one of those suggested by olds 307 and 403 as he has experience with them.

 

That Comp Cams grind has 218/218 @ .050" lift. While I have no experience with that particular cam, note that my UltraDyne cam has 217, but a bunch more lift. I would go with a cam that has lower .050" duration and more lift.

Cutlassefi always recommends a tighter LSA for low compression engines so it builds more cylinder pressure. So for that, one of the factory Olds camshafts such as the one olds 307 and 403 posted above would work.

The problem is you want a lopey idle and good performance, but you don't have enough compression to get both. Choose one or the other.

 

Yes, I do. I was still running the shim head gaskets in that 350, so just under 8 to 1 with the 204/214 Edelbrock cam advanced 2 degrees on the timing set. I degreed it in another motor was within a degree of spec. With Sanderson shorties with 2.5" X pipe dual exhaust, a stock 1900 stall 2004R and 3.42 open with a Holley reman 800 cfm Qjet. In my 3750 pound 88 Cutlass plus fat me ran a 9.9 in the 1/8 mile with ignition break up over 4000 rpm.

 

scratching the idea of a lopey idle because it’s not a race engine, is the comp cams 42-229-4 the way to go?

 

Go with the next one down, 212/212@050 or 212/218@.050. Install it as per the supplied cam card. However your gains will be minimal anyway.

 

alright thanks man I’ll look into it

 

Which one did you choose? I found your post by mistake. I was actually searching for this https://casinosanalyzer.com/online-casinos/new-casinos website online because I am looking for the new online casinos and while searching for it online, I found link to your post.

 

Probably nothing yet. Thread is only two days old.

Personally, I wouldn't put any more money or effort into the engine without addressing that low compression ratio.

 

I am going to detail the engine without going crazy, and Im looking at 42-228-4 comp cams

 

Being that it has low compression, maybe adding a turbo would be good to add ontop of it. No reason why it shouldn’t handle it

 

Remember cast pistons, soft forged rods and later light weight crankshaft all need to be considered if you boost. You will be limited to the amount and the tune will be key. Plus isn't a wider cam LSA a good idea with boost?

 

if it has 80cc combustion chambers, stocks internals mild cam with 7 or 8 to 1 compression. By not running a lot of boost should be fine. I am installing a hi flow oil pump with electric and mechanical fuel pump

 

I'm just a novice, I will say that first. I had a combination like this. I went with my quadrajet and a performer manifold with a 220/220 cam on I think a 106 or 107 LSA. I think it was made by Howards. The car actually ran great and had a noticeable increase in power. I think it had a 1600 converter and 2.73 gears. Just a single point of reference, but I liked that combination. Fun and simple.

It was like this one I think. I had a set of Headman headers on the car I believe or maybe some el-cheapo off brand.
http://www.competitionproducts.com/H...RCCL510991-08/

 

What was your compression?

 

box stock 8:1

 

Is that a cam that I should consider? Or is the 42-228-4 one alright to use?

 

I had a 800 Quadrajet, performer intake and a set of headers. The car ran great. I know it worked for me and had some lope to it. Others obviously know more, but I know that the comp 270 cam was a little of dog in low end torque compared to the Howards cam I had. I don't know why. I think it was because of the 108 LSA vs the 110. It also had more lift, but stock valve springs and rockers didn't mind it. Had great low end throttle response < 3000 rpm.

Just trying to help and give my own personal experience in a similar situation.

 

if it were you which cam would you choose the Howard’s or comp cams

 

If your asking my personal opinion for what its worth I would first before spending any money on my engine if I knew I had to use Felpro or similar .042 head gaskets I would save up a few hundred bucks and buy a set of #4,5,6,7 or 7a heads. The reason is this: no-matter what cam you choose your not going to be happy with it when you have 7.xx compression. I'm guessing your motor has 14cc dish pistons in it. If you then figure those heads at 82cc (after a valve job or just as cast) with a .028 deck height (worse case most likely from GM) and a 0.042 Fel-pro head gasket your at 7.48:1 compression from what I can figure.

At 7.xx compression that motor is going to give you 135-140 or so cranking pressure and will most likely run rich because of it with a Quadrajet if your keeping the stock carb (which if your not tell me and I will gladly buy it from you..... wink, wink).

The difference in all of this is the head gasket and the deck height. I had the stock shim head gasket because I never tore mine apart. Mine was stock. My car was/is still a 1973 Cutlass S. If you tear this apart your no longer stock, the compression is less than stock due to the head gasket.

I know you want to put the thing back together. I do, I totally get that. The problem is if your asking around about the perfect cam I can only say with the upmost 100% respect as I would tell my best friend; dude, your not going to like it.

I would sell the #8 heads on Facebook advertised as complete if they are. I would then email a guy like lemolds here on Classic Oldsmobile (his name is Larry and he's a great guy) and ask him about a set of #4,5,6,7,7A heads. They will most likely run about $300.00. If you get the 7 or 7A's you have hardened seats (I don't think their necessary though, but I'm old). I would have a $350 valve job done and have them surfaced. You will be about $500-$550 all in at this point.

Then your compression ratio figuring the #5,6,7 or 7A heads at 69cc as cast (worse case) your compression ratio will be back up to stock at 8.52:1 since you will most likely take .006 off of the heads minimum just to clean them up.

Then I would do something like the Howards cam with a 108 LSA for low end torque.

This is my .02 cents. It might be worth only a hay-penny.

 

If none of this is possible and you just have to put it together and move on then I would save some money and put in an RV cam. I would probably go even smaller than the 260/260 comp. With 7.48 compression I would most likely go with a 206/212 comp cam .443/448 lift 42-220-4 cam.

The reason I would go smaller is due to the fact that 7.48 compression might be optimistic. You might need to lean out your quadrajet as well if your putting Fel-pro gaskets on it.

 

So you tuned yours with a wideband before and after and saw it go richer?

 

Nope. I’m not an expert. I don’t even think I know anything. I will say only from experience I had a 74 omega years ago. I cracked a head with water in it in cold Michigan winter. I had to put it back together with composite gaskets. When I did that it dropped my compression with a motor with 70k hard miles on it. I noticed afterwards that I was running quite rich with black spark plugs. That was 30+ years ago. I know though the gaskets were all that was changed.

I don’t claim to know anything but what life mistakes have taught me.

 

The same thing was said above:

 

Sorry to reiterate.

 

Not meaning to scold you at all. Just pointing out a similar recommendation was given by two different people that have been there, done that so it should be seriously considered.

 

Fun71 I see your in phx. Would like to connect some time. Ever go up to 67th and Bell on Sat night?

 

No, I don’t get out to that area. It’s a 1.5 hour and 9 gallons of gas round trip for me.

 

I am going to be running a 750 Holley double pumper and considering a turbo because of the low compression. The engine is going in a >3000lbs car so it shouldn’t be that bad. I’ll look at the Howard’s cam

 

If you’re going turbo at some point, the Howard’s cam is wrong for that too.
Just an fyi.

 

So then should I just stick with my original choice?