Danp76

Hi guys, I have a 71 olds cutlass convertible with a 350 v-8. How do I identify what heads I have on the engine? Do I need to remove the valve covers? thanks guys!

coppercutlass

should be on the head next to the #1 spark plug near it . If it's a 350 from 1971 should be a big 7

Danp76

Thank you CopperCutlass, my head does have a large number 7 near number one plug. Is the number 7 head the only one available for 71? Is this a good head?..can modifications be made to make this head better? Any after market alternatives? Thank you, Dan.

coppercutlass

Yep those heads re correct for 71. Head mods all come down to your goals and what your wallet allows.

Danp76

I'm willing to spend some money to do things right. Any suggestions?

coppercutlass

I'll pm you my head specs

nuttkaze

If you would be ever so kind to send me pm with your head specs...thanks!!!!

captjim

On the 71 350, heads are not the issue. The big dish in the pistons results in fairly low compression (around 8 to 1 +/-) which limits cam choice. If you plan on a rebuild and are changing pistons, then of course you can do whatever you want, but bolting on aftermarket heads will not do much for you, IMO.

If you want to make the car fun to drive without pulling the engine, tune what you have, add a 4 bbl intake and carb if you don't already have it, and spend your money on a rear end gear change, to 3.23-3.42. That will wake it up more than engine bolt-ons.

coppercutlass

I'm sorry I though I sent them to you. I will do that tonight send me pm message so I don't forget I work nights so I can only do so much on my phone.

coppercutlass

I do agree with jim unless you really need to rebuild it. There is plenty of hp you squeeze out of a stock 350 with some fine tuning. With a good gear it be like night and day.

captjim

Not trying to start an argument, but there really isn't much HP there. Small cam, stock heads, low CR. However, there IS a bunch of torque and throttle response to be had, then use the gear to multiply it.

coppercutlass

It's all right. If he has headers maybe an x pipe better mufflers, better free flowing air cleaner.curving the dist., etc. Little stuff like that adds up I know it won't add a lot of hp but a little more always helps

captjim

Personally, i don't think headers are worth the trouble and expense on a stock engine, but a decent dual exhaust might be a cost effective upgrade.

coppercutlass

But it would not hurt. And if he builds something down the road all that stuff can be re used.

Danp76

If I decide to go right through the engine, what pistons would your guys recommend? Should I rework my stock heads or go aluminum edelbrocks? What's a obtainalbe street hp from an olds 350 engine? 400hp? suggestions?

olds 307 and 403

The Probe flat top pistons are nice and light with the thin ring pack. CP makes a high quality/price piston that will work with just a proper hone. The Speed Pro are old school but strong and affordable.

captjim

These are the kind of statements that you make that start arguments. No, they will not "hurt", but neither are they cheap. Why spend all that money and time for little to no benefit? Wait until the engine gets pulled for a rebuild, drop the headers in very easily.

coppercutlass

"Drop the headers in ". No matter what the headers have to go in the same manner if they are full length I have no experience with shorty headers but they always go in from underneath. The way I see it these things can be added on over time and when his engine is built those things have already been purchased instead of building an engine and waiting to buy everything else he already would have it. Sorry I don't have the book of JIM in my head and I don't know what you do how you do it. I didn't give bad advice just something you and I don't see eye to eye on. That's where it becomes and opinion so either keep it to your self or in this case respect others opinions since the man is asking for them.

captjim

This way usually ends up costing more money and being a LOT more work. Save up, do it all at once, except for things like rear swap.


I think you just say too much sometimes and try to support (argue) your initial position. Headers are a PITA and good ones are expensive. So, if gains are minimal on a stock engine, why do it? If you are pulling the engine, that is the time to do the headers, they do "drop right in" then as opposed to installing with the engine in the car.

coppercutlass

With a stock starter you still have to have the headers hanging to get it in. I made it easy for my self used qeather pack harnesses to make things easy so I'm not fighting the wires, bolts starter and headers. I also used quick nuts on the other side of the bolts so that the bolts hold themselves in place to tighten. The quick nuts are .010 so it does not affect the strater too much. Just saying there is a lot of little things you can do to make life easy when working on these cars.

coppercutlass

Hard or p.I.t.a is a matter of personal opinion. I have had my headers in and out so manytimes it's easy really. I know what to expect and I have done things to make easy for me. Even when I did my headers the first time I didn't find it too hard . So you might spend 20 tops 40 on new header gaskets. I used felpro blue's and I re used them 3 times before they started to leak on me. Everything we state is an opinion but there is no need to question someones opinion because there really is no fact behind opinions . Ex. Headers are a pain and expensive to you. To me they are easy and I bought a decent set that has laste me a long time. The next guy might say it's impossible based on his experience.

captjim

You argue endlessly and it is pointless. I will restate my position, IN MY OPINION, headers are not a cost effective upgrade in this application. Better to install them later with the new engine.

DoubleV

My 2 cents; if you're planning on installing headers at some time I see it as being more cost effective to do it right away ( assuming you don't currently have any exhaust system at all ) so you don't have to spend more money and time modding the exhaust pipes to fit your headers vs the manifolds.

If I wanted to install headers and was planning on removing the engine at some time, there's still an advantage to installing the headers before removing the engine; you can work out all the fitment issues with the headers before hand. That way when you pull the engine, rebuild it, and drop it back in, you don't have to fuss with header fitment because you've already done it. You have enough work to do getting the engine in without having to fuss with your headers at the same time too!

coppercutlass

That's the way I see it practice make perfect.

captjim

Unless the new motor mounts ( I am going to assume the 40 year old worn out stock mounts won't be re-used ) change things enough that it is all different anyway. I have installed a bunch of headers and engines, and IMO it is fairly simple to lay the headers in and drop the engine. But if you say your way is better, OK, sounds like a lot more work to me.

coppercutlass

He never said it was better. I never said you where wrong. Where do you get all this from. I have the original mounts on my engine and one is split I have no issues fitting mine in . I should re phrase that not split but starting to. Some of us don't mind work. Not everyone thinks alike. I keep saying that yet you keep saying everyone else's method is too much work or wrong etc. The op asked for some advice and he is gonna get mixed answers. If everyone wanted to do what you did they would pm you if they cared enough.

380 Racer

I for one, agree with Jim.

coppercutlass

I will say this. Putting in the headers while installing the engine is also not easy. I actually tried this before. I layed the headers in and lowered the engine. Now here is where my problem was. As you get the engine in it is hard to keep the headers in place. I tried hooks but the angle of the headers would not work with me dropping the engine in. Mind you I had my dad helping me I got fed up and said f-this I'm doing it the way I always do. This is from experience. To drop the engine in and lay the headers in to bolt up is not that easy because you pretty much have to lay them in there as they would sit pretty much level with the flanges outwards a bit from the block as you know headers are round and like to roll around. Not to mention you still have to fight your starter if you are not running a mini . It's also not easy if you are running just stock wire which is why I went to a weather pack quick disconnect set up. Saying it's easy is easy doing it is diffrent. From my personal experience it's much easier to do them from underneath. I have done em on a lift and believe it or not it's even harder on a lift . The last time I installed an engine which was 2 months ago was the first time I installed headers with the car on jack stands. It was way easier than on the lift. Because I had the car high enough to get the headers in and low enough to bolt em in place. That's my experience. Take it for what it's worth which to you guys won't be much but. I'm not complaining I got my routine down and it works I got no reason to complain. Not arguing just supporting why I said what I said. I have also removed and installed my headers atleast half a dozen times for many diffrent reasons I re used 2 sets of felpro blues and currently I'm running a set of flat out gaskets. So 110 dollars stretched over 5 years aint too bad. Comes out to 22 bucks a year for me. So in the long run he spent 22 bucks more or if he runs felpro header gaskets he can re use them .I was usually able to re use them about 2 times. I ran one set for 2 years and re used them and then ran em one more year tried re using them again but they leaked.

380 Racer

Working with headers is not that difficult. I agree with Jim I would wait until the new mounts were in place and install the headers with the engine. Piece of cheese.........do it all the time. On a small block the starter should not be a problem. Until the Kooks, I used a full sized starter with all the headers I used. Except for these headers I need a mini starter.

Oh by the way I install the engine and trans seperately.

coppercutlass

I can only imagine how hard it is for you guys when you have to crawl underneath and install them. I have no issues installing my headers. I have never been able to squeeze a starter in between the header pipes and oil pan. It's too wide to clear. I also think the installation method has been explained by others in this site similar to what I said that you can't bolt up the headers untill you have the strater in. I'll find the link later and post it for that thread.

380 Racer

It's very simple.......install the two end bolts just into the head so the header will swing outward. Hold the starter up between header and pan,connect wires and then install it. Install the rest of the starter bolts and bingo all done. You are making that job worse than it actually is.

coppercutlass

that's how i do it i also install my engine seperatly. I also use the end bolts but i only use one at the front and thats it untill the starter is in. i never said it was hard for me. I can have my headers in and out pretty fast with no issues . What i was trying to say is that either way has it's tricks and isn't as easy as cheese. here is a link to a very good link to header installation and a diffrent take on it from a very good source of info on here . https://classicoldsmobile.com/forums...ss-supreme.htm

here is another one that say's diffrent

https://classicoldsmobile.com/forums...s-headers.html


here is one with people putting input on sbc and olds header apps

https://classicoldsmobile.com/forums...ngine-way.html

380 Racer

Back to Jim's question........Why wouldn't a person replace the needed things as the engine & headers are installed?

coppercutlass

Jim is not the op he can start hos own thread asking questions. I did not replace mine because they where fine this last time I noticed they started to split. When I put the new engine in it's getting new mounts. If it aint broke don't fix it.

Danp76

I"m not sure if I'll do headers or not, seems like you guys are stuck on this header topic. My concern is what compents do you recommend for a good street performance engine?...piston recommendations?..cam ? carb? aluminum heads or modify my number 7 heads?

captjim

I want to thank you for that, it actually made me laugh out load. Almost as funny as you telling me to use a dictionary and spell check. Nobody clutters/derails threads more than you do.

I never "asked" anything, show me where I did. I offerred my opinion that headers were not a cost effective upgrade on a stock engine. Your advice to install headers because "it would not hurt" is ridiculous. I also stated my opinion that is is better to do it all at once and not piece-meal. Just my opinion.

captjim

We have actually covered this a gazillion times, do a little searching and see if you find any useful info. I will give you my advice, which I am sure will be countered by master engine builder Coppercutlass. Do one of two things;
1) find a proven build that you think will meet your expectations within your budget then duplicate it. Search here and ROP, you will find a lot of different combos.

2) Choose a reputable builder/vendor with experience in Olds engines, tell him your goals and budget, then TAKE HIS ADVICE. Not this or that, but all of it.

Personally, if I was starting over, I would bore .068 over, cut the crank to 2.100" and use 400 SBC pistons and rods. Either just grind the journals .025 or off-set grind and add a little stroke. The easiest is probably use a 6.2" rod and a 1.425 p/h with no offset, a virgin block will put you right at zero deck. Use flat tops and aftermarket aluminum heads. With the right cam,, converter, and gear it should run mid-high 12s and be streetable and reliable. Cost would be around $6,000 plus assembly.

captjim

This illustrates my point about you, your post are incomplete. VERY few guys have access to a lift, most don't want to do the same tedious job over and over. They want to do it, drive it, and have fun. So when you say "Putting in headers from the bottom with the engine in is a piece of cake" MAKE SURE YOU STATE THAT THIS IN IN A FULLY EQUIPPED GARAGE WITH A LIFT AND AIR TOOLS. You did not give that impression before. You do this CONSTANTLY and you are either being lazy or dishonest.

coppercutlass

I actually said it was easier on jack stands read the post's all the way through. You can mae sarcastic remarks . But for a guy who is 23 I think I have made some good strides. I restored my own car top to bottom ex rear end and trans. And I'm willing to take risk's to really find out what will last and what won't. You guys make me out to be an idiot but compared to a lot of others I got the b@lls to take risk's and not get my panties up in a bunch when it does break. I'm not gonna go on about my combo if I had done things right it would have lasted and I would have had higher et's if the money allowed for the proper carb and converter. You said it your self 13.3's aren't bad I could have done better considering I had higher compression etc. I'm done.

coppercutlass

I also don't use air tools when I'm working around the engine at all. I use my electric 3/8ths impact for exhaust and maybe for acc. Brackets but that's about it. Quit making assumptions. I'm tired of you guys hounding me. I won't let up because I won't get pushed around. I might add I had lift privledges when I stored my car at my dad's work where they had a lift for their delivery trucks . I would work on them for free to store and work on my car there now that I own my own house I got no excuse so I'm stuck working on jack stands which I don't mind either. Which is why I said this last time I did my headers It was easier and quicker on jack stands how's that for honesty.