Thread: looking for a good power combo (need help)

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i own gm performance parts crate motor #809-12499529. i have a gm performance intake and an edelbrock performer series 600 cfm carb. my compression ratio is 8.5:1. the heads are 76cc. just wondering if anyone had any good ides on what combinations of parts i should use.

Well I'm by no means a chebbie expert, but I would think the compression ratio is a bit on the low side to get a lot of help from bolt ons. Not sure how much money you want to spend, but maybe some smaller chamber heads, along with the entire Edelbrock Performer RPM package, heads, cam, intake, and carb. Looks like you probably allready have the right carb. If you have to live with the big chamber heads, then a cam change and some headers may help.....

Originally Posted by 79elcamino

i own gm performance parts crate motor #809-12499529. i have a gm performance intake and an edelbrock performer series 600 cfm carb. my compression ratio is 8.5:1. the heads are 76cc. just wondering if anyone had any good ides on what combinations of parts i should use.

What do you want the motor to do? Did you buy it and then decide that you wanted more power or what? The compression ratio will not support more cam, so be careful, you could make it slower than it is. What's wrong with running it like it is? How much money do you have to spend?

I agree with what has been said. I think a set of Edelbrock aluminum heads and RPM intake would be a good choice, but I do not like their RPM cam as its design makes most of its power in the upper rpm band. A better choice would be a Lunati Voodoo 60102 or 60103, depending what idle quality and performance level you are looking for. These cams are state of the art in cam design right now, and are an improvement over the CompCams XE line according to Harold Brookshire who designed both lines of cams. Just make sure you use the corresponding valve springs for the cam you choose.

Originally Posted by 79elcamino

i own gm performance parts crate motor #809-12499529. i have a gm performance intake and an edelbrock performer series 600 cfm carb. my compression ratio is 8.5:1. the heads are 76cc. just wondering if anyone had any good ides on what combinations of parts i should use.

With that comp. ratio you will need to look at cams that have a duration @ . 050 of 210 or less on the intake side.

well what id like to do is get an edelbrock rpm airgap intake and a new comp cam camshaft. then the edelbrock performer rpm heads. hopefully getting 9:5.1 comp ratio and running it on regular gas. ive got headers and dual exhaust. but what u really want is what my dyno n my computer is telling me and thats about 410 hp with heads.

Geez, you don't need an RPM intake. I don't understand you guys who think the motor will be faster with a bigger manifold. All you'll do is kill off the low and mid range with it, where you do 99% of your driving. Now, is you're gonna drag race/street drive with a 383 and rev it to 6,500, then yeah, the motor could take advantage of a bigger manifold.

Originally Posted by techinspector1

Geez, you don't need an RPM intake. I don't understand you guys who think the motor will be faster with a bigger manifold. All you'll do is kill off the low and mid range with it, where you do 99% of your driving. Now, is you're gonna drag race/street drive with a 383 and rev it to 6,500, then yeah, the motor could take advantage of a bigger manifold.

If we are talking heads, cam, carb and associated parts to make 400+ hp, it would seem an RPM intake would be the logical choice. The Performer is designed to make peak torque at 3500 rpm and lose effectiveness after 5500 rpm. That kind of engine is going to see 6000 rpm with peak torque being in the area of 4000 rpm or so. Why would you want to compromise top end? An RPM dual plane manifold is not going to lose that much low end like a Victor Jr. would. I would just like to know the reasoning behind your response, that's all. No offense intended.

What about someting like this?

http://store.summitracing.com/partde...0&autoview=sku

Originally Posted by 79elcamino

well what id like to do is get an edelbrock rpm airgap intake and a new comp cam camshaft. then the edelbrock performer rpm heads. hopefully getting 9:5.1 comp ratio and running it on regular gas. ive got headers and dual exhaust. but what u really want is what my dyno n my computer is telling me and thats about 410 hp with heads.

A 400 hp 350 with comp. ratio of 8.5 to 1 can be done but you will have to buy really good heads and a hyd. roller cam.

Put a supercharger on it the comp. is pefect.

no ill buy the heads and get 9:5.1 comp ratio

Originally Posted by BigTruckDriver

Put a supercharger on it the comp. is pefect.

His engine has cast pistons.
I don't think I would recommend a supercharger.

Originally Posted by rumrumm

If we are talking heads, cam, carb and associated parts to make 400+ hp, it would seem an RPM intake would be the logical choice. The Performer is designed to make peak torque at 3500 rpm and lose effectiveness after 5500 rpm. That kind of engine is going to see 6000 rpm with peak torque being in the area of 4000 rpm or so. Why would you want to compromise top end? An RPM dual plane manifold is not going to lose that much low end like a Victor Jr. would. I would just like to know the reasoning behind your response, that's all. No offense intended.

No offense taken. You could be right.

Try this site:

http://www.ryanscarpage.50megs.com/combos1.html