O.K. big block gurus, give me some cam recommendations for my build which will be on the dyno in the next week or so. I want to run a streetable solid roller.

Specs. are: 496 Cu. in. 10.5 compression. AFR cnc ported 315 head or cnc ported procomp 320 cc head. Aluminum flywheel. Close ratio muncie with 3.70 rear (currently) but will probably go to a keisler 5 spd with 3.36 gear. Intake is a factory rectangular port tripower. 2" headers w/ 3 in. collectors.

I want all the power I can get, but the engine must idle around 900 and pull 11-12 inches of vacuum and have decent low speed driveability. Would like to see 650 HP if possible. I drive this car ALOT and on many long trips so it must be durable.

Mike

 

I think something like this should work for you. http://store.summitracing.com/partde...3&autoview=sku
I know its kind of small, but you said that you want to drive it a lot, and I think the AFR heads & cubic inches will still help you meet your power goal.
If you go with the ProComp heads, I think you would probably need more cam to get there.

 

To make that kind of power I would say you should be in the mid to high 250's intake duration @ .050 with an exhaust split of 4 or so. The AFR's exhaust port is good so you don't need a big split as long as your exhaust system is good. I would try to keep net lift in the .650 to .675 range and run the new Isky Red Zone needleless lifter. Get good springs. To give you a comparison, my 10 to 1 502 with AFR 315's and a Holley Strip dominator single plane and a solid flat tappet that is 258 @ .050 with a 1.8 intake rocker made 614 hp at 6100rpm. A solid roller with the same duration would get me close to 650 hp. This was on a dyno known to pretty stingy. Should be fun ride for you. Oh, and make sure you get the cam ground on a billet core. No cast deals here. And definitely go with the AFR head if you can. My low speed driveability is fine although it cruises best at 2200 rpms or more. A roller would idle and cruise better at the same size. Need to think of the solid roller as a maintainence item for your application although I would not hesitate to use one. I will be going to one soon also.

Bill

 

When i built up my 454 .060 over Motor , 9.5-1 c.r. , EDL Oval Alum heads, EDL airgap intake, electric fans, 800 cfm Mighty Demon Carb,, SuperComp Headers, 'x' , hiflow mufflers ... I chose a Lunati Roller Cam of 232/242 duration at .050" , .575/.595" lift, on a 112 lsa ... being afraid Id have too much of a lope at idle . But once completed, it was nowhere near objectionable to me and I realized I could have gone more in duration and lift . Vaccuum sits at 12" wc with no braking problems. I ended up with 540 h.p./600 tq (gross) . Looking back on it, I really wished i had gone with an Eagle 496 Stroker Kit at 10.5-1 c.r.

 

With only 10.5 you limit the duration to about 248 I

I would leave the 3.70 rear and install a tko 600 with .82 od. See how you like it and then maybe drop to a 3.36

 

I agree with Bill. He didn't mention it but with the vacuum you want I would go with a 110LSA or perhaps a 108. Once you factor in lash, a 258/262@.050" solid roller has an effective duration of 249/253 with an .018" lash. Should be a street screamer.

Are you really stuck on the tri-power? The single planes are so good now that they might be a worthy alternative.

FYI - I am running a Comp Extreme Street solid roller, and even though I've checked the valve lash about 6 times, they only needed adjustment once, which was after the motor was heated up the first time. Now it's been 7000 miles and the lash is holding tight. I'm going to back off to checking it only every 5K miles, or once a season. Mellow idle, huge midrange and a screamin' top end - what more could you ask for?

Jim

 

Driveshaft, I like this cam. I think I could get away with the next step up even. Anyone else run this voodoo line of cam?

 

Your setup sounds very close to what I am after. THe tripower would give it a little better low end as well I think with maybe a slight penalty up top. Many of these rollers seem big to me but I realized that you have to take off about 8 degrees duration for the lash adjustment in comparing to hydraulic cams. I am not familiar with the Isky Red Zone lifter. Is this a new more durable lifter?

 

Yes, this new lifter has a bushing instead of the needle bearings. Much better idea for the street.
These big engines really tame cams down. They also have plenty of low end no matter what you do. They seem to work very well even when they don't seem a good match with the chosen compression. With a good head, and you get a cam to spin the motor a little bit, compression really doesn't seem to matter. There is a guy on the Chevelle forum with a 9.7 to 1 498 with AFR 305's and a 260 @ .050 solid roller running over 130 mph in the 1/4. He is making at least 700hp. Bottom line is you have enough compression to run alot of cam. Anything in the 250's is going to be plenty streetable in a 496.

 

The next cam up would get you there for sure, but I wouldnt count on 11" of vacuum.
I also think its getting a little large for a car with a sub 500 cu. in. motor that gets driven a lot.
If it was a going to be a street/strip weekend play toy, then it would be a great pick.
Of course this gets a lot into personal opinions of how big is too big.

 

For the 496 I had been planning I was looking at Comp's XSR grinds with either 280/286 or 286/292 advertised duration (less aggressive profiles than Voodoo line) However, rather than with a 108* or 110* LSA I would most likely have gone with 112*, especially with the larger cam, as IMHO the wider LSA would not only flatten out the torque curve and potentially lengthen how long top-end hangs on, but it would definitely yield better idle characteristics, including improved vacuum. BTW, what redline are you needing to stay under?

FWIW, tho I love Tr-Powers (I've had several), I believe you'll be leaving big chunks of performance on the table by not running a better breathing high-rise manifold on such a large mill. My $.02...

 

Maybe the 1502 Engle for that build, not sure about their distributor drive gear these days. Years ago you had to swap out the distributor gear.

http://englecams.com/catalog/new_catalog.php

 

Scott's post reminds me to suggest it's a good investment to spend the extra $ to get a steel core with an iron gear. Also, don't restrict oiling on the street, as your lifters require ample lubrication at the low rpm's you'll run at most of the time.

 

Irish,
The above is a good cam. But pick something that matches everything you want.
I had the rear wheel dyno post with the 468. I initially sought to match HP and TQ #'s. I was real close. I can get a bit more out of my combo with some more tuning. Spend some time carefully opening and blending that intake.
Although I used 1/2" carb spacers, I wanted the factory look all the way down to the original valve covers with stickers. I even internally balanced the 4" stroke to get the same size balancer as the 427. I have an aluminum flywheel, lightweight pistons, and many other goodies.
I went with a wide lobe sep to broaden the Tq and smooth the idle.

Just keep in mind that the tripower intake on those cubes will die off above 6000rpm. So you want to pick a cam and adjust the cam timing to match a power peak at or below the intake peak. You can put a 275*+ cam on it an run out of intake before the cam peaks... and then leave alot on the table.

The 4.25" stroke will smooth all cams over a 3.76". If you want peak power, low vac, and a choppy idle then go 260*/265* on a 108. Pick the same cam on a 112 to spread the power out some, smooth the idle, and increase vac. Put some zero gap rings in to increase vac 2-3" with big cams.

The tripower is the best intake that fits under a stock BB hood.

 

Howard's cams or Herbert will give you a good custom order cam, even with the iron gear.

 

I am leaning toward a wider LSA as well for the reasons you stated. Better driveability and very little power penalty. A 110 or 112 seems about right. Most of the cams would need to be custom ground to get the 112 though.

Have to stick with the tripower for my hood line. Otherswise it is a TorkerII. I ran the TorkerII on my old 489 and it did very well. Didn't have a tripower then. But many people underestimate the tripower against comparable manifolds. It won't run with a Victor jr. or similar but will equal or beat a low rise single plain and even many dual planes. Saw a dyno test in corvette enthusiast on a 496 roller motor where the tripower beat an RPM air gap and Holley strip dominator both with a Holley HP950 by 15 HP at 6400 (655HP to 641HP). Of course the problem is not everybody has one laying around or wants to part with $3000! Mine came with the car!!!

I am planing to do some back to back dyno testing on the tripower versus some other manifolds to see exactly how capable it is.

 

Love your combo and it has alot of similarity to what I am after. With another 30 cubes I have a little more room to play! Where did you get the carb spacers? I have been wanting to get something in the 1/2" range to test on the tripower but can't find any for sale. How did it effect your combo? Consensus seems to be a slightly wider lSA and maybe a mid 250's duration should get it done with 650-680 lift. Mine also looks stock and I want to keep it that way.

Also it looks like it will be the AFR heads.

 

Summit for the 1/2" spacers. The outer 2 will need to be opened a good bit. Open plenum spacer for a 2bbl. It fits and the top of the aircleaner just touches the hood. Solid motor mounts are a must. I have 1.8 rockers to get the 720 lift. 254/260 on a 112+4.

 

My brother's 439 with a similar setup but a flat LS6 intake with a BG demon 1000 did not produce 1hp/cubic inch to the wheels. I like the tripower intake. The 1967 is better but needs the l88 hood.

 

If you are going to custom order a cam, I think I might reconsider those manufacturers.
They arent exactly on top of the latest cam design and are better known for stamping out copies of other peoples old stuff.
Two good ones that pop into my head are Cam Motion & Bullet, but there are lots of other good choices out there.
Since idle quality is important to you, I agree a 112 lsa would probably work good for you, bud dont kid yourself about not giving away anything by spreading out the lobe centers.
You will gain idle quality and a tiny bit of power at 6000+ rpm, but in the rpm range where you drive the car 90% of the time (2500 rpm to 5500 rpm) you will be down on torque compared to a tighter Lsa.
The billet cam with an iron gear is real common with most of the reputable cam companies out there so it isnt hard to find. Nobody but Comp is silly enough to grind a solid roller cam on a cast core.