the cam was ground for my application. i was at the shop on and off for 3 weeks before we decided on the final build. i was asking about manifolds due too the fact sometimes things are brought up i've never heard about or thought of and i do a little more research.

there was a brand new edelbrock performer manifold already on the car before i started the 331 Stroker. so i will either try that and see how it runs for a while or go with something new. not sure yet. just looking for ideas.

 

if they designed it for use with your performer manifold, then use that.

i'm suspect that you haven't indicated the correct cam specs. i wouldn't call 560 lift that much at all. you might want to verify the number you have indicated is the duration at .050 or is the advertised duration. it seems more like it should be the advertised based on the rest of your components.

 

it will work o.k with it but a little bit off on the top rpms.

 

258 duration at .050 is a LOT of duration for a 331, and if it's a custom ground cam then the specs on the intake and exhaust will both be different. A custom cam ground to the application is also designed with a manifold in mind, so if it is a true custom cam then find out what intake it was designed to run with. Call the cam manufacturer and give them the grind number on the cam, they can tell you.

And just cuz something runs with power in someone else's car, doesn't mean it's going to run well in a street car, or run well in your car.

 

+1. We are not saying that ii is too much cam, just not the right cam for your package. Just because your engine's "brain" (i.e. cam) is telling it to take a deep breath does not mean your engine can. Does that make since? Since you have some expert advice already, as him/her what heads, intake, carb, and exhaust you need to use that cam effectively.

 

There is a possibility that the cam is right, the grinder may favor long duration cams with small intake ports to keep port velocity high for extended periods of time. But like I said, call the cam grinder and find out.

 

i guess my first post was kinda garbled. i know i need to run a different manifold, something atleast to 6500 -7000 for the engine i have built. it was discussed during the build.
that said before i pull the trigger on the purchase of of a different manifold that flows with the rest of the engine, i was just picking the brains of the members who always seem to have a wealth of info on every subject.

the exact specs on my cam are ---------Valve Timing

in.open--44 Ex.open--80
in.close--80 Ex.close-44
Duration @.050- 258 Duration @ .050-258
intake valve lift-.560 ex. valve lift--.560
intake valve adj-.024 ex.valve adj.-.024
Lobe center--108
1.6 Scorpian roller rockers

 

It looks to be a "large" cam that favors higher end power. The Vic Jr would probably work best with the cam, but again the heads are going to limit top end power. The ports are small so the long duration helps to make up for it, and will also help mid range some, but it's mostly going to be a high rpm deal. Larger heads like Vic Jr or TFS FAC 190's would make substantially more top end power. Matched with something like 4.10 or a 4.56 gear and it'll move out really well, but not something I'd personally use as a daily driver.

If you have the regular Performer RPM heads then the cam and heads are really not well matched. What intake you pick depends on what kind of power you want, the Vic Jr will make more top end, and something like an RPM Air Gap will make more mid range.

 

I am not a cam guru, but I do know how to read and have done a little research over the years. What I know is if you compare your cam to Comp Cam's catalog, the performance range of that cam is going to be 3000-7000 rpm. Comp runs a little more lift than yours, but they are comparable. Also the solid roller cams do not like low rpm running, so you will need to keep it spun above 3000 and really should run it in the 4000-5000s for this setup. If you do not, you will constantly be adjusting valve lash and will make very little power while you are in those low rpms. Maybe your small heads will help with that...I don't know.

The reason we have said that the heads and cam do not match is with that much duration, your power curve is getting pushed up the rpm scale. With that, requires more air flow capability. Small runners help keep the velocity of the air flow up, but they can also restrict air flow when your engine needs it quickly as in at high rpms. That is why you generally need to match the head runners, intake, and cam to all work in the same rpm band. Under normal thinking, you have a higher rpm cam with a lower rpm head.

I like the Air Gap. I have not received my tuned Air Gap yet, but I look for it to add a few horsepower at the topend by better matching the air flow of my 205 AFR heads but its dual plane action still lets me run it on the street going back and forth from work. That being said, I run a solid roller cam with a bunch of lift and do not drop the rpms below 3000 unless I am at a stop light. Basically, my engine lives between 3000-6500.

That is my $0.02.

 

mine is not a solid roller ,just a regular solid cam. also i run a WC Tremic 5spd and 1st gear is pretty low.