Too small a cam for my 512RB build? Here is my combo.

I am wondering if I purchased too small a cam for my 512RB engine build. Here is the combo I am putting together. I wanted it to be a street/strip buildup.But I am wondering if all that cubic inch will need more cam and duration? I would like to get a little more HP and Torque out of this combo than I originally wanted (bad planning) but here it is.

512 RB with 10.5 compression
Eddy RPM intake or TM7 (I have both)
Proform 950 Carb
Hughes 579/587 256/260 solid with EDM lifters
440source heads with springs,retainer & locks changed.
Hooker 1 7/8 Headers

This is going in a 70 Charger RT with 4speed and with Dana 4.10 gears.

It's a heavy street car, I think that cam looks pretty workable but there are guys on here a lot smarter than I. If you wanted more I would port the heads before I put more cam in it.

Sheldon

It's about 10 degrees smaller than I would run (I've built A BUNCH of them) but it'll still be very stout. I'd prefer a single plane TM7 but the RPM is still a good piece, you're going to have a ton of torque from about 3200-up, it will be fun for sure.

There was a guy in Mopar Muscle with a Tan 70 RR that ran a combo very similar to yours (except auotmatic), he won the 6-8 car street shoot-out, so don't worry too much about missing the combo by much.

Something that will help you out much more than a +10degrees @ .050 cam swap at this point would be to cut off the 3" collectors and weld-on a pair of 3 1/2" collectors to replace your 3" on the Hooker 5903's. You're torque and power peaks will otherwise be limited by the 3" collector which is the achilles heel of what are pretty well-built headers. At 511 cubes, that alone will be worth 3 tenths or more vs maybe the tenth you might see from the cam and the stock 5903's.

Here's how it's done:

I'd say run it as is. Cam choice for a street car really depends heavily on the driver. Some people don't mind really lumpy cams with poor idle while others hate them. I run cams that are a lot smaller these days in my street cars than I used to just because I got tired of the noise and hassle.

Thats a very similar grind to what I have in my 493 and my car flat out flys. The torque is awesome. I do have differents heads and headers (ported eddys, and 2" TTI), but still you should be fine.

the new Car Craft has an article on collectors/pipes...deffinately go with 3 1/2" collectors and 3" pipes...

as far as the cam...I like em big and you have some cubes there...are the heads worked at all?

Bobby/Streetwise has some good stuff for street engines like yours..

I think that the combination is prety good and would go with it. What you are willing to accept for the street vs max. strip performance will drive your satisfaction level, and only you can determine that yourself.

My cam is 10 degrees smaller than yours. I'm leaving some on the table, but I really like it's street manners and would not change it.

The heads are going to be your limiting factor on that build .

How good where your rear tires for hooking Your going to need some goods one now with the 512 I would put the motor together and try it, the four speed can be made to make up for a lot of mistakes, which I don't thank you made on the cam. I would put it in and try it, be ready to shift it quickly or let off of the throttle if it starts to go sideways in first or second gear No kidding Let us know what you decide and how it works out Stroker motors make a lot of torque and torque is King Especially in a heavy car

The heads are unported. I may just do a clean up and port match after all is said and done. But it sounds like a good port job would be worth it.

Blackcharger,

Here's my take.

If you can pick up your mid lift .200-400 flows 10-15cfm it will pay you back huge in terms of upper bottom through top end power. This is where your cam spends 2/3rds of it's time and the gains through judicious porting are well worth the effort....it's like adding extra degrees of cam timing above .200 for more power with no downside to drivability like adding seat to seat time might be.

put it on a dyno and get some #'s for me it was money well spent!

Well, you could put a little more duration on it, but with the 10.5 CR, I wouldn't get carried away. I think you will be very happy with the combo you have now.

Before I read your cam, I was going to say about 260 degrees at 0.050" with an agressive lobe (like you have). A milder lobe with 5-10 degrees would make the same power as the cam you have.

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The heads are unported. I may just do a clean up and port match after all is said and done. But it sounds like a good port job would be worth it.

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Considering the actual numbers that have been posted , it would not hurt .