hi i´m searching for suitable heads for my hevy sb with a high breathing capability; i want to build up a rpm engine. i´m not quite shure jet wheter to use my 283 for it, stroke a 283 or use my other sb, my 327. but i need heads for it that lets it breathe. the car is quite light, so i need an engine with a torque that rises parallel to speed. i want to use a singe 650 carburetor or a quad, and the torque should be max at approx. 5000 upm. which heads are good? which manifold suits? i already got a 296 degree cam. i am not shure if the edelbrock sets are trustworthy, grz chris
someone offered me 82-84 corvette alu heads with 1.94 in / 1.6 out. recommendable? other heads i found: gm performance alu heads or those: gm vortec heads any suggestions? grz chris
Stay away from the heads that were originally on a 350 or larger small block as they will have a larger combustion chamber[less compression]. Maybe you should use some cast#461/462 heads and re work em a little. if you do have to use one of the larger chamber heads as a starting point [and modify them]- I have used a set of cast #883-they have about the best flow of the stock IRON chevy heads. better stay with the 327....
First and foremost, there is nothing wrong with Edelbrock RPM or RPM Performer heads. I have a pair of RPM Performers heads on my car and it runs excellent, but there are a ton of variables. Somebody mentioned the different sizes of available heads, all that being said, to select a set of heads that will work best for you, the first thing you need to know is what pistons are to be used. 64CC heads may work and they may not. Another thing to remember, you can usually run a little more compression with aluminum heads as they will disapate the heat faster. Once you understand how much compression your going to have, I personally would call somebody like the Com Cams tech line and talk to them about a recommended grind. There are so many manufacturers and grinds available, you should talk to the pros. The one advantage of the RPM heads is they come with bronze wall valve guides, push rod guides, screw in studs and decent springs and retainers. Your going to have to put a ton of money in a set of stock chevy heads to end up with the same configuration. Just my thoughts. john
That is a lot of duration for a 283. Stay with smaller intake runners.You don't need a set of heads with jumbo runners for a wee block.
hm. one of the reason for the aluminium heads is weight. the other is that here in germany we can drive higher compression ratios because of 100 oktan fuel that is regularly sold on every gas station. thats why i am looking to get a ratio > 10.5:1, i even would prefer 11:1 so the rpm performer heads from edelbrock are adviseable? does anybody know the size of the original 283 chambers? grz
The aftermarket for SBCs is so huge that there isn't room for a poor cylinder head design. They're all going to be excellent, especially if you buy from a leading name like Brodix, Edelbrock, Trick Flow, Dart, etc. With some companies, porous castings are an issue, but I've never heard of a problem with any of the companies I've mentioned.
I'm running trick flow twisted wedge heads on the mill that's going into the Pusherman. Small combustion chambers etc etc. No reason to make comparisons it would be like comparing apples to figs. They'll work fine on your small bore small block. I wouldn't stroke the 283 if I were going to run it. Just build the 327. If I wanted to build a rever I would bore the **** out of the 283. But either mill will work fine in a light to moderately heavy car. But no reason to accept this info as gold. We haven't even met yet. Have we?
... since you haven´t been to southern germany, i don´t think so.. . i also tried to find those twisted wedge heads from trickflow for chevy sb - who sells them? summit offers only the ford version. ok, when the original 283 heads have 52-55cc chambers and the aftermarket heads available have 64cc, i have to raise compression. how? other pistons seem to be the only possibility. right? so my setup will look like this: 283 block dome pistons edelbrock performer rpm heads (64cc) (for now) 296 degree cam roller rockers are there brands adviseable for bearings? especially for rpm applications? grz
After reading the entire thread I'm left with SEVERAL questionS. What are you trying to accomplish? What is this going in? Where are you going to drive it, under what conditions? What is the weight of the car? What rearend ratio are you running? What is the rear tire size (dia.) Where do you think you need to develope maximum torque (and why). I could go on but you get the drift. You are planning a high RPM engine. Do you need a high RPM engine. Is it your only goal to watch the tach as it p***es 8,000 RPM? If so , put in a 6 cyl tach, you'll get a hard on everytime your in the car. Now if you think I'm just trying to be a smart***, I ***ure you I'm not. I just think it's wise to have a plan, when you build an engine, they are too expensive to make major mistakes and waste your money on something that just doesn't suit the application. Why don't you sit down and list what it is you want to accomplish with this engine. Like I said, what's it going in, how are you going to drive it,is it an everyday driver, is it a race only car? Then lay out a plan to accomplish those goals in the most realistic fashion. You can build a good every day driver engine for a couple of thousand dollars with careful planning or you can build a decent drag motor for $10,000. Where do you want to end up? I have a feeling your not real experienced at this or you wouldn't be asking about heads for a high RPM application, you'd already know. BTW, if you think I'm being an *** I can ***ure you I've been there/done that. After owning a high performance engine shop for a number of years I see some of the pitfalls that young guys all into. As a current reference I'd recommend you PM Racefab here on the HAMB and ask for some advice. He is more current on what the hot setup is and will give you some sound advice. Frank
youre rigth, to this point i have just rebuild several standart-smallblocks. this rpm engine is going to be my first modified engine. at the moment i have an 283 sitting in a small 60s p***enger car which has a weight of 1180kg (2360 pounds i guess). the engine´s good times have been long gone, last time i went on a dyno there were 120,5 hp left on the real axle with its max. torque of 318nm at 2.800 rpm (starting at 1.500 rpm). but even this engine keeps my tires spinning; i have 195/60/14 tires. i can´t use bigger ones because of several reasons. so i planned to rebuild an engine, altering its charakteristika. i thought of raising the torque to its peak at 5000 rpm, trying to avoid those "starting at 1500 max torque plateaus". my impression was that an single plane open plenum manifold along with suitable good flowing heads should help to accoplish this. my first plan using a 283 seems not to be working (no heads that fit); so i use my 327. i do not think "youre an ***". in contrary, i like specified questions helping me reaching my goal. i am a quite direkt guy, i can be "an ***" myself...( if you want to call people with a clear mind like that... ) grz oh, here´s a picture of the car, maybe it helps getting the impression...
Well maybe this is my chance to "be an ***" but I got a dollar that says your hopped up 327 is going to make significantly more power than your tired old engine at those low RPMs. If tirespin is already a problem with 234lb/ft max, get ready for an uncontrollable car with that much torque at 1500. Sounds like fun!
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