Camshaft characteristics?

[Andy Blaisdell]

I just picked up this cam from a friend who bought it a long time ago but never used it. New in the box. It is an SSI or Super Stock Industries Camshaft. Hydraulic flat tappet camshaft. What I am wanting to know since my looking at this cam spec card is a bit confusing, especially the numbers which I think stand for Intake and exhaust center lines being different. At least from my perception. Here is the cam spec card. Please help by enlightening me as to how the engine will behave to a cam with these specs. Power brake capabilities as well. Thanks.

 

[Andy Blaisdell]

Got on a camshaft calculator online and this additional information was gathered. Some is repetitious.

Intake center line 108 degrees
Exhaust center line 116 degrees
LSA is 112 degrees
Overlap is 71 degrees

See what I meant by way different center lines?

 

[Bighead440]

We installed this cam in a buddy's Dart that had a '69 383HP in it. This cam idled well and ran pretty strong, his complaint was not enough lope. He was on a strict budget and PAW had the whole kit with lifters for $99 I believe. I imagine in a 440 it would really be tame. No issues in a bone stock HP with the red, dampner-equipped valvesprings and stock rocker gear. Ran low 14s in the Dart with 3.21 gears.

 

[Bighead440]

Power brakes would be no problem, and no high stall converter needed either, a 11" factory converter would be fine. It's milder than the specs would suggest.

 

[max1196]

The 5 degrees of built in advance would make it calm down from what the specs are suggesting. I calculate this would need 9.35 compression ratio to maintain a correct Dynamic compression ratio. Otherwise rather calm for a big motor.

 

[Andy Blaisdell]

Yeah, I wasn't looking for calm. I want a loping idle but not so radical I have to run a vacuum pump for the power brakes. He also has a new in the box Comp Cams 292H which is brand new but by looking at the specs it looks to be too radical. Both cams are for sale if anyone is interested. I will provide his contact information, upon request.

 

[Bighead440]

If you have the valvesprings for it and hopefully adjustable valvetrain, a Comp XE275HL or XE285HL would work good with lopey idle sounds and acceptable vacuum.

 

[Andy Blaisdell]

If you have the valvesprings for it and hopefully adjustable valvetrain, a Comp XE275HL or XE285HL would work good with lopey idle sounds and acceptable vacuum.

Regular stock 1.5 rockers. Thanks for the cam recommendations. I do have a cam which cam in the 440 I just purchased but the numbers (which are hard to read) on the end of the cam don't cross reference to anything. The intake and exhaust lifts are both approximately .474 and in between the first 4 lobes there are remnants of purple paint. Anyone have any idea as to what this cam might be? As best I can tell the number on the back of the cam is 200867 but it looks to be double stamped and unclear. The heads have heavier than stock springs with dampeners.

 

[65sporty]

Andy your building a 440 aren't you? It would be a good street cam in a 383. I just looked at the 292H and you may be able to get away with it running a 4 speed but may be low on vacuum with the 110 lobe sep.

 

[Andy Blaisdell]

Yes, building a 440. My main concern is that I'm running a 3:23 gear in the rear end and that cam according to Comp Cams needs 3:91 or better.

 

[65sporty]

Ok, you may like the XE725 much better

 

[Andy Blaisdell]

Will that give a loping idle?

 

[LocuMob]

If you have the valvesprings for it and hopefully adjustable valvetrain, a Comp XE275HL or XE285HL would work good with lopey idle sounds and acceptable vacuum.

I was told by Steve Dulcich to run the XE275HL in the Polara with a 440, slight stall, and 3.55's, needs 9.0:1 compression as per company website. The XE285HL says 10.0:1, higher stall and deeper gears. I picked up the 285 for cheap, have touched ran this can in a car before, if so, how streetable was it? Trying to determine if it would work for my driver or if I should out it in my Dart, which will be more "wild".

 

[LocuMob]

Will that give a loping idle?


The intake and exhaust lifts are both approximately .474 and in between the first 4 lobes there are remnants of purple paint.

It should give a lope.


You just described the .474 Purple Shaft cam from Mopar Performance/Direct Connection. I run the .484 in my car, as they've been the tight price, free! I like it, has a choppy idle and I run my power brakes no problem. The power comes in around 3500 and pulls til I shift. The XE275 HAL should have a better pattern that idles like a hot rod, but it's more technologically up to date than the 50 year old design can I run.

 

[Bighead440]

IF the ".474" mystery cam is the Street Hemi MoPar PurpleShaft, it will work awesome in a 440 with an 11" stock converter and 3.23 gears. Good combo, even quicker with 3.55/3.91 gears, 4.10 really would be too much IMO unless you had a 383. Shift at 5600rpm with stock heads and valve gear, make sure the valvesprings are up to the task.

 

[LocuMob]

IF the ".474" mystery cam is the Street Hemi MoPar PurpleShaft, it will work awesome in a 440 with an 11" stock converter and 3.23 gears. Good combo, even quicker with 3.55/3.91 gears, 4.10 really would be too much IMO unless you had a 383. Shift at 5600rpm with stock heads and valve gear, make sure the valvesprings are up to the task.

What's the difference going to the .484? Lose some vacuum, what else? I'm in the same boat as Andy, I get some of it, the rest I don't.

 

[Andy Blaisdell]

I will be running 516 heads on the 440 with Speedpro L2355F flat top pistons with 4 valve reliefs. heads are updated to 1.74 exhaust valves. I am guessing about 10 to 10.5 to 1 compression. Correct me if I am wrong.

Yes, the street hemi cam is the closest lift wise in description to this cam according to stuff online.

 

[Bighead440]

What's the difference going to the .484? Lose some vacuum, what else? I'm in the same boat as Andy, I get some of it, the rest I don't.

The .484" PurpleShaft needs more gear and cam. I would say 3.55 minimum, 4.10 max on gear and maybe a 2500+ converter. Vacuum still adequate but not as plentiful for power brakes. My .02c

 

[Andy Blaisdell]

Will be running a 4 speed

 

[Bighead440]

I was told by Steve Dulcich to run the XE275HL in the Polara with a 440, slight stall, and 3.55's, needs 9.0:1 compression as per company website. The XE285HL says 10.0:1, higher stall and deeper gears. I picked up the 285 for cheap, have touched ran this can in a car before, if so, how streetable was it? Trying to determine if it would work for my driver or if I should out it in my Dart, which will be more "wild".

The 285 is pretty lumpy.
I had this "XE285HL" ground on a 112LSA (smoother) but with a slightly longer duration exhaust lobe. Should mimic the shelf cam pretty closely due to similar overlap. This is a TRW 6pack piston engine with milled open chamber heads, so 10:1 compression probably. 500+hp easy-peasy.