Advice on Cam Specs

[bobs66440]

Hi guys,

I'm rebuilding my 440 fairly stock with maybe some port work but nothing crazy. Running HP manifolds and dual quad intake. Just wondering if this cam will work. It came with the car. I'm looking for a little lope in the idle but I don't want to sacrifice performance.

Thanks!

 

[rumblefish360]

That cam will not give a lope when the engine is all warmed up, thenterline needs to be numericaly low. That one has a 112 centerline. (half way inbetween the 107 & 117 numbers) Also, when valves open and close quick, it can add to the note that comes out. The advertised duration numbers vs the ones @ .050 show this cam to have slow opening valves. This looks like a Crane cam or a Wolverine.

You can find a similar one from Comp Cams with a 110 centerline or you can ask them to knock it down 2 degrees to a 108. That'll chop at idle real nice.

 

[Cranky]

Do you know what your static compresstion ratio is? I'm no cam guru but that looks to me like it's going to give your engine a lot of cylinder pressure and if your compression is already up, that's just going to put it over the top and you'll have ping issues. Now if your compression is low, then that cam will help it think it has more....but like 360 said, fairly smooth idle.

 

[1968_Roadrunner]

Not much lift either. Probably close to stock, with more duration. Just my .02

 

[bobs66440]

Ok, I thought it was kind of mild, just figured since I already had it....

When the time comes I'll just get one that the engine builder recommends. Thanks guys.

 

[Cranky]

Another thing you can pay attention to is when the intake opens. Advertised rates are just that and advertised numbers are usually listed for anything before .050 lift. Not much is happening before .050 lift and the numbers that are listed @ .050 is what should catch your eye....and any cam that lists an intake valve opening that's '0' @ .050 and closes more than 30* ABC is usually going to have a very high vacuum and pack the cylinder full. Not a real good cam for higher compression engines but works well in low compression engines....

 

[rumblefish360]

How are you thinking of building this up? (Looking for insight)
Gear ratio and tire size please.

 

[bobs66440]

How are you thinking of building this up? (Looking for insight)
Gear ratio and tire size please.

I plan on building it fairly stock or with as much power and reliability as I can afford. It's stock now but very tired and using a lot of oil. It's going to be a low budget build (hopefully under $3500.) I have stock heads and plan on going through them, but would like some port work to help them breathe better due to the dual quad I am currently running. The cam a little lumpy but not crazy. The bottom end will remain stock with new rings/bearings etc...maybe some decent pistons (suggestions?). I am putting on factory HP exhaust manifolds. The r&p is 3.55. The tire size is 245/60x14. It's going to be primarily a street cruiser...but healthy sounding/running.

 

[bobs66440]

Do you know what your static compresstion ratio is? QUOTE]

It's a '66 motor, probably out of an Imperial or something. I'm not sure, I think it's a stock engine...sounds very stock anyway.

 

[rumblefish360]

I plan on building it fairly stock or with as much power and reliability as I can afford. It's stock now but very tired and using a lot of oil. It's going to be a low budget build (hopefully under $3500.) I have stock heads and plan on going through them, but would like some port work to help them breathe better due to the dual quad I am currently running. The cam a little lumpy but not crazy. The bottom end will remain stock with new rings/bearings etc...maybe some decent pistons (suggestions?). I am putting on factory HP exhaust manifolds. The r&p is 3.55. The tire size is 245/60x14. It's going to be primarily a street cruiser...but healthy sounding/running.

Factory-or-Edelbrock dualquad? I see nothing out of the hood in the avatar, I just wanna make sure it's not a tunnel ram. I know you didn't say tunnel ram, I just wanna be sure LOL!

Slug wise, if your going to use the cam above, I'd look for a slug at around 9.0-1 and not higher than 9.5-1. It will make good power in a very acceptable way for a true driver and drive everywhere. (Even with mom in law.)

A Comp. valve job and nothing more than a light bowl work on the heads.

I'd use the cam.

 

[bobs66440]

Factory-or-Edelbrock dualquad? I see nothing out of the hood in the avatar, I just wanna make sure it's not a tunnel ram. I know you didn't say tunnel ram, I just wanna be sure LOL!

Slug wise, if your going to use the cam above, I'd look for a slug at around 9.0-1 and not higher than 9.5-1. It will make good power in a very acceptable way for a true driver and drive everywhere. (Even with mom in law.)

A Comp. valve job and nothing more than a light bowl work on the heads.

I'd use the cam.

Ha ha, yeah, no tunnel ram. It's a Offenhauser dual plane w/ 2 Edelbrock 600's. I have the secondary carb coming in after about 20 deg. of rotation of the primary throttle shaft and both hitting full throttle at the same time.

The guy will also have a dyno available so I'm hoping to get some decent numbers...I would like 400+ hp and 500+ tq. Don't know if that's realistic or not.

BTW, it's an Elgin cam if that means anything...

 

[Cranky]

How does it run now?

 

[bobs66440]

How does it run now?

It actually runs very well now, aside from the oil usage and it has a hot hard starting issue. It could use more power, but pulls pretty hard.

 

[Meep-Meep]

I think Rumble pegged it as Wolverine. I ran one in my 68 302 Mustang and it ran OK. Funny how the specs are the same except for lift. The idle had a faint rumble to it if you listened really hard. There might be better cams for your application (like the factory magnum cam), but since you have this one it shouldn't hurt you. As mentioned verify the compression requirements, however, I don't think you will have any issues with 9.0:1 as long as you shoot for about 160 PSI of cylinder pressure for regular 87 gas. Missing the match between compression and cam will hurt you!

The advertised intake closing point is the most important for determining cyl pressure because you can't build any pressure when the valve is off it's seat. Compression is your friend if you run the proper gas to support it. From the sound of things you may not notice much difference compared to the cam you have now, if the one you are running is mild.

The intake you are running is a divided plenum single plane and very similar to the factory inline dual quad setup used in the early 60's Chryslers. Those also ran a progressive linkage very much like (or identical to) the 426 HEMI. The divided plenum gives an improved signal to the carbs and that can only help. Also, the divided plenum makes the 600's more palatable on the street. If your AFB's are jetted to the factory specs then I'd say they are sized about right for your engine.

 

[bobs66440]

The intake you are running is a divided plenum single plane and very similar to the factory inline dual quad setup used in the early 60's Chryslers.

Hmm, that's interesting. I never knew that was a single plane. Thanks for that info. I never thought to research it. It works really well though. I just have to solve the hard starting while hot issue. I'm not sure if that has the crossover or not. If so, do you think I should block it?

 

[rumblefish360]

Fiar weather driver? Block it. Must have it in the cold weather for what ever, leave it open.

Though these big blocks take awhile to warm up, I really don't think it'l make a huge difference open or closed off.

 

[Meep-Meep]

25 yrs ago I used to run a Torker with the exhaust heat open on my 383 and never had a starting issue, but these days it's a different story. Carbs do not like this new gas, at lest not out here in CA. I would block the manifold heat for sure and possibly add some thin phenolic spacers under the carbs and route the fuel line away from heat. Not using a mech fuel pump might help also.

From the pic it looks like the Offy I have. It's a single plane but don't confuse it with the full open plenum variety.

 

[bobs66440]

Yeah, it's a fair weather driver...though we usually cruise until the snow flies, then the car goes away for the winter. I think I will try the phenolic spacers...it can't hurt. Thanks!