thinking of using something in the 230-232 intake at @50. range. my question would be, does a large cube engine (496) require more cam than a 454, all things being equall? im looking for about a 6200 rpm limit. thanks Dave
__________________

Yes

Yes
that means you need a BIG stick!!!

I have been advised something in the 250-260 range for a street/strip car. high 240-250 for a hot street car.

I went on the advise of Harold to use the 402A7Lun solid ft for a hot street/strip car.

Advertised Duration IN/EX: 288/296
Duration @.050 IN/EX: 255/263
Gross Valve Lift IN/EX: .612"/.630"
Lobe Sep Angle / Intake Ctr Line: 110/104
Valve Lash IN/EX: .024"/.026"
RPM Range: 3000-7000

I'm running a Ultradyne/Lunati 272/282 (238/248 @ .050) in my 498. Its pretty tame, idels with 10-11" of vacuum @ 900 rpm but still has a nice lope at idel. I'm sure it would like more cam but budget says no for right now.

Makes nearly the same power as my 461 with the same cam, I really can't tell any difference other than it idels a little smoother.

Ran a 11.95 @ 114.5mph a couple of weeks ago compared to a 11.98 @ 115.5mph with the 461 last year.

Mine has a 264 @ .050 and .715 lift in my "hot " street 496. You do need a bigger stick than you are thinking. Good luck.

Whos running a cam in the 230s int. and 240s exh. with around
500 cubes and stock (ported) GM oval ports?
Thats the plan with this combo, something real streetable, but good power. It should go mid 11s were thinkin, and be a nice driver. Anyone have something similar?

I'm putting the Lunati Voodoo 60204 hydraulic flat tappet in my 496. Pure street driver only. I hope it's enough cam? I'll soon find out.

Thats pretty much what I've got, here are the specs:

498 cubic inches
454 2 bolt block
Eagle rotating assembly, steel crank with I-beam rods
SRP pistons, domes cut to yield 9.6:1 static compression (.002 deck)
74' 781 oval port casting with 2.19/1.88 valves, pocket ported.
Manley valves, Lunati springs, retainers & keepers
Ultradyne/Lunati 402A2Lun 272/282 0.550/0.570 solid lifter cam & lifters
Comp 3/8" pushrods
Comp roller rockers
Edelbrock Air-Gap RPM manifold
A well used 850 DP, air horn removed
HEI distributor with Performance Distributors internals
1-3/4" x 3" Hedman headers

The rest of the car specs are in my sig. Mid 11's and a nice driver very doable.

Three years ago Harold recommended his Ultradyne 288/296F10 for my 496. Duration @ .050 is 255/263. It's a pretty big cam even for a 496 in my opinion. It seems to make pretty good power but I think it's a little on the large side for my heads which are GM Performance aluminum oval ports with 2.19 intake valves, and 110cc chambers. Look at my dyno graph. The hp curve looks nice and smooth and then it ubruptly dies at ~5650 rpm. It's not fuel cause I had a rock solid AFR all the way to the end. The ignition should be up to the task. So what's left? Heads?

http://www.chevelles.com/showroom/data/500/dyno4.jpg

I'm betting its your exhaust setup - small aint it?
looks like it cant breath.
What heads?

My cam is 252/263 makes peak power at 6200-6300 with 049 heads.

I'm betting its your exhaust setup - small aint it?
looks like it cant breath.
What heads?

My cam is 252/263 makes peak power at 6200-6300 with 049 heads.

2" primary, 3.5" collector headers, 3" x-pipe exhaust. I gained 36 rwhp and 25 rwtq over the 2.5" h-pipe system it replaced. The gains were from 3000 rpms and up and the curves look identical.

Head are GM Performance aluminum oval ports.

I built a 489 for a guy about 3 months ago. He picked most of the parts, including the Voodoo 60204 cam (233*/241* @ .050"). It has mildly ported 781 heads with big valves installed, 10.4 compression, heavily ported Weiand Accelerator intake, 1" open spacer, and a Holley 830 carb. It uses a Transmission Specialties 10"XLS converter, T-400, and 3.55 gears. 1 3/4" Summit headers and 2 1/2" mandrel bent exhaust with Summit Turbos and pipes to the bumper.

The idle sounds exactly like an original LS-6 Chevelle. There is a ton of vacuum and the throttle response is incredible. Torque is NOT an issue and it is a blast to drive. Excellent street manners. The engine is all done by 5500 rpms, however.

I believe that the engine would like a slightly larger cam, maybe like the the 60205 VooDoo. It should still have PLENTY of torque and probably pull to 6200 or so. BTW, the current combo is right on the edge as far as comfortably using pump gas. If he used the next larger cam, pump gas would surely be no problem.


Randy

Good info ToyzRMe, maybe I should have gone with the 205 voodoo. Ah well, I just bought the 204 voodoo last week. I'll just use the 204 with my 188 rect heads

sheetmetal, a few other factors besides just displacement need to be considered when sellecting a cam,
your rear gear ratio,stall speed,compression ratio and intake design, the heads used, the valve sizes, plus the average rpm range that your driving style tends to keep the engine in need to be factored in, but as a general rule youll want to have about 10-15 more degrees of durration in a 496 and a slightly tighter LCA than a compiable 383 small block, having the same basic set up,if your more familiar with those.

Keith
what kinda carb
intake
what mufflers
and you do have an air filter thats big - right?
Is tha cam too advanced?

Holley 950HP, GM Performance dual plane (same as Performer RPM), Dynomax Ultra-Flo 3" mufflers, same air cleaner you have on your Camaro. I installed the cam 4* advanced.

I have since switched to Multi-Point EFI with a high rise single plane manifold. The new dyno graphs look exactly the same as with the carb. However, we were able to flatten out the drop off after 5650 rpms by leaning it out. But it's still there.

kaa, somethings way off on your engine ! my little 460 with that same cam runs 10.77 at 123 mph with race rite ovals and ran 11.10's at 121 with iron ovals. that cam is not at all too big on a 496 dude!

Hey Guys,

Below is a pic of a 496 I built for Skier_Bob and his '71 Chevelle. The combo is as follows:

- 454 2-bolt main block with studs, torque plate honed and zero decked
- Edelbrock Performer RPM heads, lightly ported and new competition valve job
- Eagle stroker crank and rods with JE/SRP forged pistons, 10.3-1 cr
- Performer RPM Air Gap intake
- Lunati VooDoo 60204 cam and lifters
- MSD HEI and Accell sprial core wires
- Edelbrock 750 carb that was reworked and matching fuel pump and lines
- Walker DynoMax 1 3/4 x 3 headers flowing into 2 1/2 exhaust and 2-chamber Flowmasters
-TH400 trans with a 2500 RPM stall and GV overdrive
- 12-bolt posi with 4.10 gears

In Bobs words - The engine flat kicks Azz!

It has a loud, deep and authoritative exhaust note with a slight lope. The torque is amazing with instantaneous throttle response. The engine pulls hard to 6000 RPM with no sweat and comes very quickly in first gear!

I thought this cam was going to be on the small side for my liking (I wanted to use the 60205) but it exhibits great street manners. This cam is a nice choice between power and driveability.

Good Luck :D

http://www.c-dperformance.com/00_Big_Red_2.JPG

Sheetmetal, I ran a Crane Hydro roller with 226/236 @.050 and .59/.61 lift in my 502 with a 950HP, RPM airgap, GM Alum ovals, 10:1 compression, 3.73 gears and a TH400. It was awesome on the street and ran a 11.8@113 with zero traction in 1st gear. Power wise the cam was done by about 5600 and the valves floated at ~6200. I would run the cam again, but I would drop my gearing to at least 3.31's

I now run a solid roller (251/262@ 0.050, .660 lift) that pulls till at least 6400 or so and only makes enough vacuum for ~3 stomps on the brakes at a time. I don't think the cam is my limitation for rpm now.

Depending on what you want to do with the car and what YOU think is streetable, the range you are looking in will likely make a great street cam.

Sheet,
How high are you going to turn the engine rpm wise? An engine with a peak rpm of 6000 will not need near the cam an engine designed to go 7000.

Chris

Chris
He wants to shift it around 6000 or low 6s.
Its more of a resto/cruiser, with power brakes and ac.
He talked to UDHarold, and ended up ordering a VooDoo - 231/239,
a bit on the mild side, but it should pull to 6 - we hope.

[quote=KAA;1062723. I installed the cam 4* advanced.


KAA, this cam comes with 6* advance ground in. if you installed it with another 4*, this may be your problem. did you verify icl. with 110lsa, dot to dot should be 104*ICL.

i run this same cam in a 468 with 781 oval ports, 2.19/1.72, 10.4-1, performer rpm and a 1000hp carb. it pulls to 7000 rpm with no effort. i havn't dynoed it but my azz tells me its still pulling pretty hard.

i hope you get it worked out.

mike

[quote=KAA;1062723. I installed the cam 4* advanced.


KAA, this cam comes with 6* advance ground in. if you installed it with another 4*, this may be your problem. did you verify icl. with 110lsa, dot to dot should be 104*ICL.

i run this same cam in a 468 with 781 oval ports, 2.19/1.72, 10.4-1, performer rpm and a 1000hp carb. it pulls to 7000 rpm with no effort. i havn't dynoed it but my azz tells me its still pulling pretty hard.

i hope you get it worked out.

mike

Mike,

Good catch. Sometimes it is the simple things that are overlooked.

KAA, this cam comes with 6* advance ground in. if you installed it with another 4*, this may be your problem. did you verify icl. with 110lsa, dot to dot should be 104*ICL.

i run this same cam in a 468 with 781 oval ports, 2.19/1.72, 10.4-1, performer rpm and a 1000hp carb. it pulls to 7000 rpm with no effort. i havn't dynoed it but my azz tells me its still pulling pretty hard.

i hope you get it worked out.

mike

Excuse my poor wording there. What was trying to say was that I installed the cam on the 106* intake centerline, or 4* advanced from 110*. It actually checked out at 105*. Whether that was straight up or not, I can't remember. If it's already ground into the cam, then it must have been straight up.

Motorhead 62 is right. I love the 60204!!

Rafel, thanks for fielding the questions for me. as Rafel pointed out i went with the voodoo hydroroller 60212. the gears are 3.55 with a 2500 stall. ported 049 that flowed 309 on the intake. factory air, power breaks, power steering, rpm airgap. this more of a restro cruser. after talking to Harold (super nice guy by the way) i felt this would be a good choice. thanks for the help guys. Dave
P.S. now if i can find a good valve spring?

I'm gonna buy this copy of a CC 288AR solid street roller but in a solid lifter cam for my 496 that Harold designed just b/c I was bugging him for quite a time to do it!!

"pdq67,

I've finally designed something, now I just have to make it......
A solid flat tappet replacement for the Comp Cams CB-288a-R10 their 11-692-8------
CB-288A-R10 288@.015 246@.050 158@.200 .622" valve lift 38-70-78-30
UDHarold's 285@.015 249@.050 161@.200 .618" valve lift 35-70-74-31

Their cam sells on their web site for $363.67, and the -8 in the part number means it IS NOT a steel billet. Lifters cost a good amount, too.
My cam will be a standard high-quality proferal cam--what solids have been made of for 30 years--and will cost around $168.75. Good Americian-made mechanical lifters are available at less than 25% the cost of solid roller lifters.
My cam stays .0176" away from the edge of the lifter, and I have had other cams that get closer to the edge go 100,000 miles on the street. The seating velocity is the same I have used on those 100,000 mile cams. Valve lash on mine is .018", on the Comp .020".
Because of changes in oil quality over the past 10 years, I would recommend using a lot of caution in breaking in ANY flat tappet solid or hydraulic cam.
The Comp Cams is symmetrical, mine, as always, is unsymmetrical. Look at the timing differences at .015"---My cam has a 4* longer power stroke, meaning more torque into your crank at ALL rpms, and a 3* later intake opening point, for less reversion and higher port velocities, again at ALL rpms.
At .050" and at .200", my cam is 3* fatter---Not only is it filling the cylinder faster, it has MORE time to do it.
The result---MORE POWER everywhere.
Now to get you guys some made......

Harold"

Harold said it use’s Chevy solid lifters too!

pdq67

PS., I WON'T run a solid roller cam b/c of not wanting to find out when a lifter goes bad!!!!

For comparison, I ran a 230/242 113LSA hyd roller in the 402 .030 motor for a short while. Was tme enough at idle and ran well to 6200 or so. Run a 233/236, 112LSA in the 460 motor, pulls like a frt train to about 6000 with instant wheel spin in any gear. I would consider a 240/248 good for a 496 motor.