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I have a 91 camaro with a 383,10.5.1 compression,extreme energy 294/306 519/523 with 1.6 rockers, performer rpm air gap intake, holley 750 dp,out of the box performer rpm heads,hooker super comp 1 3/4 headers. currently the car has went a best of 11.80 at 115 mph pulling a 1.64 60 ft. on motor with a 26in m/t. Now i have the oppertunity to buy a set of dart pro1's with a 200cc intake port 64cc cambers they flow 264cfm at .500" intake and 180cfm at .600" exhaust.
Will these heads help or hurt my current 1/4 mile times?

The rpm heads flow 233cfm at .500" intake and 170cfm at .500" exhaust.
Any suggestions would be helpful.......thanks.

 

The RPM heads are a 170 or 190cc ? I thought they were pretty small.
Either way, yea, the Dart's would help out flow wise, and seem better matched to the combo, ie 383, big cam, etc.

11.8 is pretty good for your setup as is. That's quite impressive, IMHO.

What size is the chamber on the Darts? They are iron vs the Edelbrock AL heads, correct? So you *may* want to watch the compression on that.

 

the chambers on the pro 1's are 64cc and they are aluminum.
the runners are 200cc's the edelbrocks also have a 64cc camber.

 

You would probably gain a little top end power by switching to the dart heads because of the larger intake runners and but I'm not sure it would be enough to justify the time and cost of installing them. The Pro 1 heads would give you a lot more room to improve later. They respond very well to porting so you may want to consider having them ported, that would definately make it worth the trouble. Good luck, whichever way you decide to go.

 

Well it looks like i am going to go ahead and get the pro 1's, My friend is going to buy my edelbrocks from me.While i have her torn apart i am going to go ahead and install a comp extreme energy hydraulic roller, havent decided what grind just yet. Thinking of going with a little less duration, the car will be driven on the street a little more, any suggestions on durration?

 

the 286hr is a popular one. Or it might be the 282hr, I forget which one is the roller. Since you're going roller, it'll run smoother, and you'd have about the same power. Win win.

 

Well i just checked the comp cams web site and was looking at the extreme energy XR286R SOLID ROLLER,or the extreme energy XR288HR........can't decide if i want to go hydraulic roller or solid roller. ...........remember this car is only a weekend warrior so i don't care about everyday drivability.
You guys probably have more experience then i when it comes to choosing a cam shaft so your suggestions would help. Thanks

 

I was hesitant like you are to go with a solid roller after hearing the stories about noisy valve train problems and constant lash adjustments. But after switching over to a solid roller I won't ever go back to a hydraulic roller in a weekend street/strip type car. My car picked up power in all rpm ranges and revs much higher and faster than before. I don't think it makes any more noise than my old hydraulic roller cam either, its about the same. I set my valve lash in the spring and check it a couple of times through the year and thats it. I would highly recommend going with a solid roller, you won't be dissapointed.

 

AWSOME YOU DON'T KNOW HOW HAPPY I AM TO HERE THAT!!! i AM DEFINITLEY GOING TO GO SOLID, I WANT TO THANK YOU FOR YOUR REPLY!!!!
I WAS A LITTLE WORRIED ABOUT LOW END POWER BUT I AM SURE IT WILL PICK UP A DECENT AMOUNT OF POWER THRU ALL RPM'S CAR WENT 11.80'S WITH THE OLD SET UP AT 115MPH ANY IDEA WHAT I SHOULD EXPECT WITH THE PRO 1'S AND THE SOLID ROLLER CAM, ALSO THINKING OF REPLACING THE RPM AIR GAP WITH A VIC JR MANIFOLD.YOUR CAR IS PRETTY FAST AND IT RUNS WHAT IM WANTING TO RUN SO ANY ADVICE WOULD BE APPRECIATED! THANKS FOR YOUR HELP

 

what about idling with the solid roller? stop and go traffic? i heard that was a big no no...?

 

The car is only a weekend car, really will only drive it to the track and back.
Have not heard much about idle,stop and go with solid roller. Can't be much different than a hydraulic roller, just a little noisier and more maintnence on vale lash.

 

I've heard of some people who run solid rollers on the street using special lifters that have a groove for oiling. I'm sure it helps oiling in a car that sees lots of idle time but for a limited street use car I'm not sure it would be worth the expense. I wouldn't want a solid roller in a daily driver type car anyway.

Your combo will probably run better with a single plane manifold like a Vic Jr. if you go with the solid roller so I would definately make that change too. Your 750dp carb will run well but I'm sure you would pick up some mph with a 850 or 950DP carb.


I'm sure you can get down to a 11.4-11.3 or better with a XR286R solid roller cam, Dart heads and Vic Jr. If you have the heads ported I'd expect very low 11's or maybe even high 10's. Its gets harder and harder to shave off tenths once you get that fast though...lol Good luck, let me know what you end up going with and how it works out.

 

Thanks for the help! I will definitley let you know who it turns out.
Thanks again.

 

You can also groove the lifter bores.

 

HOW BIG OF A GROOVE?

 

Comp cams sells a tool to do that. Look for a "lifter grooving tool".
It's a small groove, maybe .020" deep or something.

Your capslock broken by chance?

 

Well went ahead and installed the darts with my existing cam and am going to take her to the track this saturday night, hopefuly the car will pick up a few tenths! hope i did not hurt it by switching to the pro 1's
will post track results saturday night!!!!