Thread: Cam and carburetion

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In about three weeks I'm going to be putting together a +.030 350. The car will be used only for occasional cruises and an occasional trip to the strip. No more than about 300 miles a month. I'd like to know what you all think about the combination (obviously, anything can still be changed except the block). I'm a bit concerned that I might be over-carbureted and under cammed.

Block bored to +.030, TP honed, and decked to 9.005 which should be 0 clearance with my pistons.

Rotating assembly balanced.
Eagle 5.7 rods, SpeedPro hyperutectic coated pistons, Melling HV oil pump, Clevite 77 cam, rod and main bearings, Pro Topline 58cc vortec heads (flow 224 cfm @ .500), SI swirl polished, undercut valves (1.94/150), Comp Cam(CC) 1.52 roller tip rockers, CC 12-242 cam (.484/.487 w/1.52 rockers, 224/230 @.050), CC 911 springs, Power Plus airgap vortec manifold, Edelbrock 750 1407, Holley 97 gph electric pump.

Plan on redlining it at 6500 RPM +-a few. Going to run .039 gasket so I'll end up somewhere about 10.6 to 10.8:1 (octane booster, please). Along with this is the usual suspects, double roller chain, 1 pc. pushrods, Moroso 7 qt. pan, ARP bolts where it counts,etc.

What do you all think about the combo, particularly cam and carb? Thanks!

Thank you DennyW. That answers my carb issue. Anyone have any comments on the cam? The trans is a built 350 and I'm not against stepping up the converter.

I noticed one thing in your post right away.You talk about redlineing at 6,500 r.p.m.s.+ Why? Your cam is out of power way before this.Why stress this engine?I would think max. power would be in by 5,500 r.p.m.s.Always remember bigger is not always better when it comes to carbs.

oldman2, just a couple of thoughts....

If you're planning on buzzing the motor to 6,500, you're gonna need more cam like Erik said. Why do you want to rev that high anyway? And why do you want to run 10.8 c.r.? You already know it's gonna be a pain in the ass. If you research the back of the can on the octane booster products, you'll find that "1 point" actually means 1/10th point. That crap is worthless. Another thing, you might think you're gonna be able to run a stock converter with that cam, but I think you have a rude awakening coming. It's gonna be another pain in the ass and you'll have to stand on the brakes at stoplights. Also, you'll most likely have to find another way to make manifold vacuum if you're using power brakes.

I suggest that if you want a performance motor, start with a bigger motor so you won't have to compromise so much on your build.

Thanks Erik and techinspector. I wasn't planning on running it up to 6500. It was just a limit of how high I would be willing to go if someone suggested a more radical cam. Too many pieces that I wouldn't trust over that.

The 10.8:1 wasn't on purpose. Missed on this when I was putting the thing down on paper. I used SpeedPro's spec showing 9.97:1 for 58cc heads when I went with it. Didn't take decking into consideration. Dumb! Dumb! I think I'm correct on the 10.8:1 using 5cc for pistons, .039 gasket, and 0 deck clearance. I would rather it was down at 10:1, but I'll run whatever I have to run in it to make it work. It's not ever going to be a daily driver, just a toy.

On Comp Cams dyno test with this cam, they show 17 in. at 1000, so I'm not extremely worried about vacuum. If I pull that much, I may try 1.6 rockers on the exhaust (I have sufficient spring clearance to run the .515 lift that would give) and I will be checking valve-piston clearance before I bolt it up.

I have rebuilt a number of rice burners and 4 and 6 cyl engines over the last 35 years, so I'm not quite new to this stuff, just busy trying to catch up on what's happened over those years in the world of performance. The last built engine I put together was a 331 Chrysler (went in a 53 Stude. Never was able to pry the shoehorn out. If you ever want to see exhaust problems, try that mix. Exhaust ports line up perfectly with the steering column.), and most before that were 3/8"X3/8* flatheads. It has been a long time. ;>)

This forum has been an incredible resource to me and I have used the search function innumerable times to gather info. I hope you all realize what a valuable source of information you are. Thank you for being here.