blunsford

What are the specs on your cam and how much vacuum do you run at what idle speed? List your experience (likes and dislikes) and what mods (Like a high stall converter) you had to do to make it work right ON THE STREET. Just curious. It seems to me the cam manufacturers seem a bit conservative with their recommendations.

MotorHead

CC 282 solid cam 236/236 deg @ 0.50, .495/.495 lift. with 15 in. vaccum at idle. Great cam, I have a 4 speed with 3. 08 rear end, still hauls down low and
screams up top, runs good at all RPM's :D

Bearcat

Crane solid roller 246/254 (int/exh) @ 0.050", 0.615" intake, 0.636" exhaust, 110 degree LSA. Let's see, if I remember right I had about 9 in hg at about 800 to 1000 rpm idle speed? It's been awhile since I checked. But it's enough (barely) to operate the headlights and power brakes. This cam is on a 427 BBC. Compression is 11:1 and I'm using heavily ported and bowl blended oval port heads with 2.30"/1.88" valves, with a single plane and BG Gold Claw set at 775 cfm. Exhaust is courtesy of Hooker sidepipes with spiral baffles.

The cam doesn't really come on strong until about 3500, and then it's wild until at least 7200 rpm. I've got my Crane Hi-6 ignition set to 7200 for insurance. This motor really needs a good set of 3.70 gears or steeper. The 3.36 gears in the rear end now give it a pretty incredible top end, but slow down the midrange from its more explosive potential. Putting the power to the ground is always a challenge, but it's fun. Problem is, I have to be seriously putting my license in jeopardy to really make this engine feel good on public streets. And all the cops can hear me from miles away!

mrvette

Mine is a ZZ9 TPIS cam in a roller 355, about 15 on the scale....
at 850 rpm....

GENE

Chuck Harmon

I have installed the same roller cam Bearcat has above, but have not driven the car yet. My previous cam was the factory L88.

.562/.584 gross (no lash)
.538/.558 with .024/.026 lash
354/360 degrees duration @ 0 lash
264/270 @ .050" at lifter
112 lobe center

69 Vette with ROD 6 speed and 3.08 gears. 3.27 first gear makes 1st gear equal to M22 with 4.56 rear gear. Hooker side pipes with uncapped JCL baffles, D port factory rectangular aluminum heads, L88 factory intake, 950dp Holly HP carb, 12:1 compression, MSD billet non vacuum distributer with 6AL ignition. Running 39 degrees total advance, 24 degrees at idle, all in by 3000 rpm.

483 RWHP open exhaust, 477 RWHP with baffles.

Cam makes great power. Absolutely loves to live upstairs. If I still lived in rural Colorado I would have been happy as a clam with it. In urban San Jose, CA, my eyes burn from sitting at stop lights due to all the overlap and unburned gas spewing from the side pipes.

Idle speed is 1200rpm with slightly more than 7" vacuum. Driving around in the first few gears, 2500 rpm is absolute minimum without bucking. 2200 rpm cruise at about 75mph in 6th is ok. Got 15 mpg at such a cruise up to San Francisco and back. All highway driving, no getting on throttle. Engine turns absolutely ferocious above 3500 rpm. I shift at 7,000rpm. Simply jumping on the throttle in 3rd breaks the tires loose. Doing so even in 4th at about 100mph can break them loose if the road isn't perfectly clean.

The L88 really is a wonderful cam, but not well suited for city driving. Amazing when you consider it has been around for almost 40 years. The guys at the local speed shop where I dyno'd the car were simply astounded to see the power my car made on their dyno with virtually all 69 factory spec parts. There was another 69 L88, a genuine one, owned by a friend of mine named Jay. He made very similar numbers to mine on the same dyno proving that it wasn't a fluke. I made about 9hp more, but he had a miss at the top end believed to be from crappy plug wires. Neither of us did any tuning on the dyno, we just ran them.

I am looking forward to driving with the Crane #138601 solid roller cam. My expectations are to have the best of both worlds. Decent idle without burning eyes and ferocious upper revs. We will see.

Chuck


[Modified by Chuck Harmon, 10:30 AM 11/19/2003]

72Shark

CC270 Magnum. It pulls about 15" at 800 RPM. Hauls butt.

MasterDave

Isky 270/280 MegaCam (hyd). Lift is 465 in and 485 ex. 112 lobe center. Idles crisply at 650 rpm. I'm at 9.5 cr. Nicest cam I have ever used and pulls hard from 2000 to 6000. Cleans up easily off idle too. About 14-16" vac :thumbs:

SpyderD

Comp cam magnum 280 with 230@.050 on the 355. Strong lope at 600 idle - about 8" vacuum. Headlights work when not under load. Brakes are a little mushy, but part of that is still due to some air in the lines I think.

You should ask about compression as well, I believe that makes a big difference with big cams. The 10.7 compression is a good match for my cam - I have good (but not great) response on low RPM's (under 2000). Great, almost scary, response on high RPMs. Traction is a problem if I step on it on any speed under 25 MPH or so. I still use stock gears so a gear change is my next plan.

toddalin

Crane version of the 327/350 hp cam with 331 CI and 9.5 CR. Pulls 14-15" at idle of about 750 rpm.

jimtreber

298 degree 246 @ .050 .510 lift one-up special ground by Comp Cams.
16 inches of vacuum at idle with Rhoads lifters (say what you want, they work for me) smooth idle at 550 rpm with lifters clicking away.
3000 stall KenneBell Switchpitch
406 with true 11 to 1 compression
4.11 rear

1976

Gordonm

Comp Cams 294S 248 dur at .050 wit ha .525 lift. I run about 9" of vacuum at 900 rpm. Little soggy below 2500 rpm but at 3500 to 7000 it hauls. I would have put in a little more compression if I had to do it over. I am running about 10 to 1 now

yellow 72

SpyderD,
I'm running that same combo with 13" of vacuum with incredible throttle response. You might try dialing in as much initial timing as you can and manifold vacuum at distributor...makes a big difference.

Mike :cheers:


[Modified by yellow 72, 1:24 PM 11/19/2003]

Vetterodder

Comp XE-274, 230/236 @ .050, 10.35 cr, 331 ci. Vacuum @ 850 rpm was 10.5 with standard rings, increased to 13 with Total Seal gapless rings. Decent low end power with 3.36 rear and wide ratio M20 but I probably wouldn't be happy with a close ratio tranny.

GDaina

Comp Cams 288R Solid Roller 244 @.050, 110 centerline, .623 gross lift, idle@850, vacuum 14-15". No complaints, love the cam

Ironcross

One, 612/637. LS7 454. 3500 stall turbo 400, 4.56 gear, 850-900 idle. Two, 560/580. L88 427, 4.10 gear, 4 speed, 850-900 idle. Stock L72 427/425, 2800 stall turbo 400, 4.10 gear, 800-850 idle. Standard lead in all of them, 36-38. :cheers:

ukvette72

CC Extreme Energy 268, 12 in vacuum at idle (800 rpm) 2400 stall converter, 3.36 rear, 9.5:1 compression, Edelbrock aluminium heads. I think i should have gone for more compression. But all told very pleased with it.

SpyderD

I may do that. I put a new engine in - this engine is new still so I let the engine builder set the initial timing which I believe is at 13 and I haven't wanted to play with the settings too much until it was broken in. Now that i have 500 miles on it I am ready to mess with it. The advance is hooked up to the ported vacuum, it jumps too high when I hook it up to manifold so I probably have to play with the vacuum advance settings. Now you should note I have an auto '81 and an which has the incredibly wimpy stock 2.87 gears for that year.
Also - i recently fixed a one of the headlights that had a minor vacuum leak, my vacuum has probably gone up from that 8" since I did that.



[Modified by SpyderD, 1:58 AM 11/20/2003]

Nomad78SA

I have a 388ci with 10:5:1 compression and a 700R4 W/ 1800 stall running the Comps cam 268H, Gross Valve Lift 0.454 0.454', Duration At 0.006 Tappet Lift 268, Lobe Separation 110
I have 15-17" or so of vacuum and a idle at about 700rpm and a nice lope.
No traction from a dead stop and no traction can be obtained from 15-20 mile per hour start also :cheers:
I have got to finish this vette soon
Neil in Tenn


[Modified by Nomad78SA, 5:54 AM 11/20/2003]

fast0

Great idea for a forum, great info. I found this forum as I was looking for info like this to give me more acccurite on drivability street manners in a cam selection. I have learned the hard way as this cam I have is already my 2nd in my very light weight roadster. I just had to register to add my 2 cents regarding my 327 SBC in this roadster. I hope someone will find this info helpful. I don't consider myself a professional at building engines or own the high dollar calibrated tech testing tools so keep that in mind. I currently have a Lunati 60112 roller cam in it. http://www.lunatipower.com/CamSpecCa...rtNumber=60112 700r4, 2500 stall, 10" converter. Rear gears are just 3.00.
Some specifics of my build. .030 over, flat top pistons, .017 down in hole.
Heads are Procomp, 2.02/1.62, 58cc chambers, and 210 runners. Full 1.5 roller rockers.
4.125/.026 head gaskets. Online compression calculators say I am @ 11.3 compression.
My cranking compression is 185psi +/- 4, by my gauge. This cam is closing the intake @ 67 ABDC.
Long tube patriot headers with their attached mufflers. Single plane high flow intake with a
Holley 650 dbl pumper done up by Super Flow Carbs to 670cfm. Timing is about 18 @ idle (1300) to 36 @ full advance @ around 3200. Full mechanical advance. Vacuum is 10.5 taken @ idle, 1300rpm @ engine temp of 180. I do not have any vacuum assist mechanisms.
I get by fine, no ping on premium 92 octane non ethanol fuel.
This engine is very strong. I have no complaints about HP. If this hot rod had a standard transmission all would be fine.
At a stop sign, the car still tries to pull even with the 10 inch, 2500 stall converter. You have to be pretty hard on the brakes or slip it into neutral.
If you keep it in gear and you are at a long light, it may load up and stumble and might even die.
Lowering the idle just makes it stumble on accelerating. The sound is a nice rumble, crisp snarl when reved, that I love and everyone else does too, but I’d rather have a better driver.
The cam’s duration I thought was modest for my application, but with the 66 OL that this cam has is too much for my pleasure.
Then there is the issue of fouling plugs. No problem with them if you keep the RPMS up. I tell my kids to run it around town in 2nd, 3rd if getting out of town on highway. I have tried different recommended types & heat ranges.
I know I should probably change the intake to a good dual plane and the converter to a higher stall but that is another thing and not why I have posted this here.
I hope this helps if anyone is considering this cam.

jnb5101

CC 235/249 @050 with .510/.495 flat tappet hydraulic lifters with Seal Power pistons with -16.80cc. Stock 781 heads. Idles at 1100 right now with 13" vacuum, but I'm still working on the timing and carb! Screams past 2000 RPM and hope to get the low end better.