Since the OP is asking for help is the reason for this reply. I will re-iterate what Olds307 has said before. I would hesitate to put a power-adder on a soft, stock bottom end. As a mechanical engineer your stock bottom end was never meant to handle that stress. This subject I do know about. I have been a mechanical engineer for better than 30 years and I think that decision would be quite costly and frustrating as an end result.

This is not an uneducated decision. It is a well informed, educated reply. These engines are not built with this intention or consideration. Engineering has changed over the years. In 1976 boost was not a design consideration which exponentially increases metallurgical stress.

With that said, if power is what you need and you don't mind possibly having to go through some learning curves; turbos can be a lot of fun! Just know that having a spare engine ready when something goes awry is always a good idea, especially if you have to go to work the next day.

 

For a low compression, turbo build you’ll need something on a wider lobe sep than a 110. A 114 is more the norm for a turbo build.

 

with everything mostly stock on the internals and it going in a light car you have a cam recommendations?

 

How does the lunati 10420483LK look?

 

Go for it. It'll be a lazy POS, but you'll be happy you've got a big cam in it.

You've gotten a ton of responses, all telling you the same thing: you don't have the compression to run a big cam and you don't have the bottom end to run boost. If you don't want to listen to reason, then go for it. Learn by trial and error. Mostly error in this case.

 

Alright I won’t boost and I’ll just try the lunati

 

This. ^^

Attaboy! Glad to see you can take advice. That cam sounds perfect for a mild street engine -- no power below 2500 RPM. Just the ticket!

 

Lol, truer words have never been spoken!!

 

Yep, it’ll be a total pig.

 

Nobody even knows what secret car this is going in, or the gear and converter?

he said it’s going in a lite car..it sure isn’t the 76 vista it came out of.

did I miss all the main criteria for picking a cam?

one thing you don’t do is change the compression to fit the cam, which is what I see being suggested here. If you are wanting to keep it together, there are cams specifically designed to build cyl pressure in low compression smog motors without removing the heads.

there are off the shelf cams that can wake that dog right up…gonna add headers at least?

 

I think that's because he seemed a bit keen on using a particular cam, then suggested an even larger one. Did you not notice that?


That is what has been said for the last 2 pages.

 

Here we go....

 

 

the very first response was about its dismal compression..he never said a word about which cam.

later he started to thro out cam suggestions. He clearly doesn’t know how to pick a cam, and admitted it.

soooo, then the experts jumped in because his cams were on the big side. We still didn’t know any details on the car…you see how it started to go in circles from then on?

What gear? What trans and converter? What car? Hasn’t even been asked….but the experts already know the cam is to big 🤣🤣🤣🤣

the fools are out a day early

 

I'm no expert. I just made a suggestion based on my own experience with what I assumed a similar situation. I even stated so multiple times.
I stated my car, the equipment I had, the compression ratio I had and the cam I used. I stated every parameter for my suggestion.
I stated my car was a 1973 cutlass S, stock drivetrain, headman headers and the stock Quadrajet.
I then gave the cam that I used and stated how it worked in my car. Nothing more and nothing less.

I don't appreciate being called a fool. I can say I don't appreciate it at all. I was trying to help someone else given what has worked for me.

With that said I'm all ears. I would love to hear what cam is the winner, with maybe the reason for the various choices.
Maybe a few suggestions based on different scenarios?
All ears and eager to learn.

I am very educated. I assure you not a fool and I can also assure you that I have more than enough capacity to understand.
Am I an expert engine builder? No, as stated. I am a 30 year mechanical engineer with a Masters from MIT and a PHD in pure mathematics from Michigan State.

Please enlighten this "fool".

 

So let’s strip this down a bit:


So please enlighten us as to what cam you think is appropriate with this “dismal compression”.

 

I guess its not much fun to comment when you openly insult people by calling them "fools" and then get called out.

 

With the cam that OP appears to have settled on, that engine would be a dog if you installed it in a Toyota Echo.

But your point is well taken ...

@Jay C , why don't you tell us more about the car this engine is going into and what king of driveline combo you plan to use. The more information you give, the better your chance of getting a cam recommendation that will work for you.

 

Don’t rank on me for the car it is going in, I got this engine for free and I need an engine right now for this car. My 1990 Jeep Yj is common for swapping a sbc into but I have an Oldsmobile. I and going to reuse the np231 transfer case and regear the splines in it to work. I am going to get an advance adaptors for a Ax15 tranny which came stock in the car. The rear end will be most likely a ford 8.8 with 4:10 gear ratio. I will also have a limited slip installed aswell. The only reason I am doing this is because the original engine died and because I have this 350. It will be fine.

 

For a Jeep I would really lean towards a cam that would make lots of low RPM torque. So keep the duration conservative.

 

it seems to be hard to find one for a stock Oldsmobile with low rpm do you know of any?

 

I've had lots of luck with cams in the 200-210 @ .050 duration range with LSA 108-110 and .450 - 470 ish lift. Ive also had luck with the stock 455 cams.
I'm not trying to repeat, just remind, since Jay_C is asking. I don't think for your Jeep you will see much difference in most cams in this range. FYI.

 

What size tires? Low end torque is what you want.

 

either 35s or 37s

 

42-220-4 very strong torque, excellent mileage and smooths idle

42-221-4 says strong torque through low end and mid range, good idle.

these fit stock applications and being that I will be running shorty headers peformer 2701 and 750 double pumper which one seems like a better combination ?

 

Definitely NOT the Lunati that you were thinking of. Maybe try something along the lines of a Comp Cams XE250H. Google it. You could probably go with a little more (but not much more) lift, and I know Mark ( @cutlassefi ) usually recommends a single pattern for Olds, but this is more or less in the ballpark. Should develop some decent torque and move that little Jeep out a lot better than that Lunati would.

 

the comp cams 42-220-4 kit looks decent to me what do you think

 

Issue is OP does not want to hear that the engine he got for free is a smogger turd and that's why he got it for free. He also does not want to hear that the answer is head work, when he already has had them cleaned up and painted. Many people come on here wanting to hear a specific answer because they are already down the wrong road.

I bought my 442 for a good deal because the previous owner put in a "w-30" cam into a car with a 3.08 rear. Car falls on its face until 3500 rpm.

 

it’s a simple rebuild this is not a performance engine all the measurements are perfect and should not have any problem coming together

 

Kind of an inverse confirmation bias?

That would be fine. So fine, in fact, that it's the exact same cam that I just told you about.

 

I think he needs validation from 4 or more posters to validate the selection.
Here's my vote........
X 2

 

alright thank you, I realized after I sent the message. I bought it with the included kit should be plenty thanks for the help

 

I realize this is a bit late and you already ordered a cam, but there are many, many places that sell Olds “RV” style cams that have around 200* duration @ .050” lift.


https://www.summitracing.com/parts/mel-cl-soc-9



https://www.summitracing.com/parts/mel-mc1287


https://www.summitracing.com/parts/m...ake/oldsmobile

 

It’s alright, I’m sure this will work fine

 

I looked up the specs and I agree, that appears to be a good cam for your application.

 

Thanks again

 

Keep in mind also that with that cam you probably won't need a 4.10 gear. Something around 3.55 should do it, plus it'll get better gas mileage and be more streetable, if that's a consideration.

 

I keep it in mind I need to find something to fit the rear of the car I’m not there yet

 

X5. See way up in post # 30. Glad to see this is coming together.

 

Remember that a Wrangler has two drive axles, so a gear change means everything x2. And he said 35” or 37” tires, so 3.55 wouldn’t be low enough for those monster tires.

That brings up a whole new discussion about the appropriate axle gear ratios.
Gear ratios for the AX15 transmission are: 3.83, 2.33, 1.44, 1.00, 0.79, so with 35” tires the axles may need closer to 5.xx gears.