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Discussion Starter #1
Like the title says... I want to run a 12.5 down the 1/4 mile..

I am undecisive on my cam selection so far... I have read tons and tons of forums online for the past 3 days NO JOKE! and I can't seem to get the right answer to "I WANT THE MOST HORSEPOWER WITH VORTEC HEADS" and I dont care if I have to shave the heads down for more lift since they are only capable to .470 - .480 roughly...

I recently bought the Edelbrock Air Gap Intake for this setup which I know will help me, but I need a cam that will mix we'll with my setup and get me into the 12's... I want again to be close to a 12.5

I've seen the 7102 Edelbrock cam but nobody seems to mention it while running 12's (all everybody and anybody say the 7102 Grind IS OLD AND THEIR ARE BETTER AND MORE MODERN GRINDS AVAILABLE) but nobody has proven them??... All I have been reading are the XR268-286 cams (roller cams) in the 12's & even 11's... Help me out please, thanks!

Here's my setup..

1979 Corvette
3500 lbs (W/ me in it)
350 SBC Gen I (non-roller)
G-Force Tires (Not peeling out at light)
820 CFM Holley Carb
Vortec Heads
Edelbrock Performer Intake
284 Crane Cam
Stock Bottom End
2000 Stall Converter
700r4 Corvette Servo + Shift Kit
3.42 Gears
13.6 1/4 Mile @ 100 MPH (my best time)

CAM SELECTION:
7102 Edelbrock
RPM Range: 1,500-6,500
@ .050 inch Lift 234 int./244 exh.
308 int./318 exh.
0.488 int./0.510 exh.
LSA 112
 

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I would suggest getting a bigger stall, higher gears, and some sticky tires. A good quality stall will net you the most gains for the money. Don't focus some much on the cam. You could send the heads off to be ported and have a custom cam ground to the head flow. That's what I would do. Just my opinion.
 

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Comp Magnum 292, Lunati has a Street Master, and Isky has a grind with similar specs with more lift and duration than the Edelbrock.

My 70ss ran 12.9 with the Comp some gorilla ported angleplug heads, weiand team G, 10" converter and 4.11 gears on soft street tires. It ran 13.3 with the Lunati and stock heads. I'd imagine with good heads and soft tires it would have been deep in the 12's in both cases, and your C3 is lighter. I daily drove both cams by the way.

Its going to take more than just a cam change, so I agree with Mystery on more converter and gear. Your carb is a bit on the large size too. I never went past a 750 cfm, and most 350's don't even need that. Most cam companies have good tech support. I've bugged them a few times.

Honestly, I wouldn't hesitate to go roller.
 

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I wouldn't be suprised with that outcome. Set the suspension up for drags and would probably hit mid 12's.
 

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Discussion Starter #6
We'll I want to keep this car as a weekender so I still want to have the drivability for highway use and all the goods thats why I have the 2000 stall and 700r4, the carb was actually put on by my father-in-law... I would like to put my 600 cfm carb back on and see if it will work better...? I dont want more gears cause again I want to use it for highway use and 3.42's I believe are in the middle of street/strip use...

I dont want to go roller cause if I'm gonna spend that money I might as we'll buy a ls1 and throw that in the vette! lol but yeah I know the rollers get an easy 50 HP + over the reg block.. but I dont want to go roller..

My tires don't peel out on take off, they actually launch pretty @ 2,000 Stall! :)

I was hearing about some Hydraulic 302 cam that has high lift .540 or so... (old school cam) and it should get me into the 12's.... I will get the specs soon hopefully so you all could help me out with that.
 

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If you get a good quality stall it will drive like stock around town and still lock up on the highway not losing and MPG's. New technology in conveters is amazing. The old school converters were never meant for street driving or highway cruising. They were annoying because you had to bring your RPMs up to match your speed just before they would kick in, not so anymore. I drive a 3600 converter and really wish I went with 4000 because the street manors are so good. If you go with a bigger cam you will need a bigger stall because you won't be able to manage a higher idle it wants with a low speed converter, you will have to hold both feet on the brakes at a stop light.
 

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stall/gears/tires

3600 stall with a good cam to make use of it (you are seriously limiting your options on cam with a 2000 stall) at LEAST 3.73 gears but 4.11 would be better, and a dedicated set of drag radials for the track. not saying you can't have a 12.5 quarter mile daily driver but... there are some trade offs.
 

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Must have been busy last summer when this was first posted...

You have more carb than you need (although it probably isn't slowing you down), but not enough intake. The Performer dies at 5500 RPMs, and your cam still has another 1000 RPMs left in it. Get a Performer RPM.

Your engine can't use much more than 650 CFM. A 700 would feed it fine, and drive better on the street than the 820 you have. No more than 750 for what you've got.

As already noted, you need more stall and gear. 3000 probably isn't enough. 3500 to 4000 would be more like it. If the car feels like the secondaries kick in a second or two after you launch, which I'm betting it's doing, it's because the converter is keeping the engine below its "real" powerband. If you can determine what RPMs that is happening, get a stall just above that. Your 60' times will drop like a rock.

3.42's are cruising gears. 3.73's would help get you off the line. Of course, you're going to need traction to match. I drive my car to the track on highway radials, then change to stickies when I get there. Although I don't know much about the G Force tires and the track - with a good suspension and good track prep, they may hook okay.

I hope your Vortec heads were modified for higher lift. They typically can't take more than .480" lift before the retainers hit the tops of the guides. And the stock valve springs are junk. I'll assume that was taken care of. Regardless, I don't think your cam is holding you back, but the rest of the package is.
 

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I have to agree. Stall converter and sticky tires will offer the best gains. In actuality, a larger cam with your current stall will probably slow you down. It is probably too small for your current cam. Then edelbrock you have chosen will be a dog. It need at least 11 to 1 compression ratio.

That being said I would recommend the following:

Edelbrock rpm manifold (if it fits)
Comp xe274 or lunati voodoo 276 cam
Matching springs (you will need to modify the heads for the lift)
3000 stall converter
3.73 - 4.10 gears
Drag radials

You have to think of the whole combination. The parts need to compliment each other.
 

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This thread reminds me of the good ol high school days. Where outcomes to races could be predicted by burn out contests. Allow me to set the scene. I was a Sophomore (92') had a 82 swb Chevy truck that looked faster than it ran. Finally blew the 305 and tossed in a way over cammed 350 (Bowtie LT1) stock short block with 194 heads, Team G high rise spider intake, with a Holley dual fuel line carb. Yeah I know, but I was a kid and you couldn't tell me shit. The engine looked very cool but I could barely keep it at an idle to show off that cam. I had run into someone even dumber that I. We swapped intakes and carbs and he threw in an extra hundred bucks. (He had a Dual plane victor jr and a 600 mechanical secondaries Federal Moguel carb) my truck ran a lot better when I made the swap. Still had idling issues until I installed a lawn mower throttle cable so I could advance the timing from inside the cab. It wasn't long unt my dumb ass got headers and a true dual 3" exhaust. Of course I put flowmasters on. Mind you, every thing in the driveline was stock. Man with that exhaust, I might as well have pitched an anchor. Once again I had to learn from the old timers. I'm not quite sure how fast it really was. It seemed fast to me though. One day my uncle was giving me shit about my exhaust and made a bet with me. The bet was : I can make your truck faster by putting back on the OEM exhaust manifolds. Yep, he was right. Over the years my ignorance hasn't improved too much. So when I hear about CFM carb debates, I think about the truck. Sorry I didn't indent, but I'm posting from my phone.
 

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