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Running stock 302 - 11:1 Pistons, 30-30 cam, 480 dist, etc., and it idles just like it should with the 780 carb. 900 RPM. Only mod to carb is bump of primary jets from 68 to 72. Vacuum 8-11 in-hg at idle. Dist at 12 degrees initial. Runs and drives fantastic on the street with pump gas.
 

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"The secret to a good performing engine design is simple... choose ALL the 'go' components for the load and rpm range the car will be used for 95% of the time.
Cam headers carb....match the lot
Then dial the engine in .. carb and timing "

That is the best advice anyone can give...
If you call Crower and ask them to design you a cam you need to give them the car weight, trans gear ratios, rear ratio tire height etc then the most critical thing needed outside Cubes is intake runner volume, flow numbers from .100 to .700 on your heads.
Dave Crower did a 636 lift 280 dur solid roller for a 302 with 186's and it made 12" of vac fat torque curve and with 350 ft# by 3500 and 475+ HP at 6500 and still climbing. Very easy to drive but roll into hard and it would light the tires up without effort.
The results speak worlds for their thoroughness, driveability, great vacuum and unreal real world performance.
 

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The only reason stock 302's had an 800 Holley was to make the 800 SCCA-legal for the Trans-Am series; the '64-'65 Corvette 327/365hp engines (essentially identical to the 302 except 25 more cubes) revved to the moon with 585 Holleys (2818).

Years ago, when I had my Z's 4053 carb off for restoration, I ran the car for a couple of months with a 600 vacuum secondary Holley, and it was an improvement - mainly crisper throttle response. If my car wasn't so original, I'd have left the 600 on it. Unless you're going to race it, a 600 will work just fine. :thumbsup:

:beers:
 

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I agree, do not ruin your carburetor drilling holes in the throttle plates. Close the primary butterflies and increase your initial timing to 18*-20* and the total to 34* unless you are going to mix some racing gas with the pump gas in your tank. You will need more initial timing to keep the idle up to 900-1000 rpms. The cam isn't designed to idle. Also do not waste your money on a carburetor that is too small like the 600-650. Here is an article with some good information that will help you understand setting up your distributor and timing.
 

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Close the primary butterflies and increase your initial timing to 18*-20* and the total to 34* unless you are going to mix some racing gas with the pump gas in your tank. You will need more initial timing to keep the idle up to 900-1000 rpms. The cam isn't designed to idle.
You can accomplish the same thing without cranking in all that static timing and shortening the curve; set initial at 10*-12*, centrifugal at 24*, all-in by 2800-3000 rpm, and use a "B28" vacuum advance (starts @ 4" Hg, fully-deployed at 8" Hg) connected to full manifold vacuum. Streetable, idles nicely at 950-1000 with 9"-10" of vacuum. :thumbsup:

:beers:
 

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And there's more,,,,,,
First, grab a copy of this months HOTROD magazine. Turn to page 122. Marlin Davis has some math for us. He maintains that the old 'smaller is better' rule, when it comes to carbs is bogus. The formulas that lead to that myth were based on conservative assumptions. As Marlin often does, much info is contained in that half page story. I'd put some of it up now but my keyboard doesn't support the math characters needed.
In fact, his story centers around similar engines we've been using in this thread.
Don't have a copy? Just get a big carb.
But here's a tid-bit from personal expierience that seems to contradict 'bigger is better'.
A few years ago I was running my 1200cfm Retrotek TBI at the track. The new SR cam made me too quick; 11.20's but my tech card was only good to 11.50. Instead of being thrown out of the race I went back to the tech inspector and we put our heads together. What worked was simply backing off the throttle linkage about 80%. You could just see the plates moving. Bingo. 11.55's. The 80-20 rule saved the day.
Now, was it the electronics that kept the car nearly as quick? Not a clue?:confused:
 

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You can accomplish the same thing without cranking in all that static timing and shortening the curve; set initial at 10*-12*, centrifugal at 24*, all-in by 2800-3000 rpm, and use a "B28" vacuum advance (starts @ 4" Hg, fully-deployed at 8" Hg) connected to full manifold vacuum. Streetable, idles nicely at 950-1000 with 9"-10" of vacuum.
Just adding .....For non EGR engines... EGR engines have curves/ VA specs quite different for the lean burns.
And all in 2800 rpms.. this was the spec for the 302 Z engine....but keep in mind, the cam the carb etc where all designed for WoT track...on the fuel formula and lead 40yrs ago.. and a engine that has never been bored....
I would seriously think about slowing that curve down a little also...3000/ 3200.

2500 to 2800 is more of a spec for octanes around the 105 and compressions 10.5 to 11.5.

just from observations from my own experience, dialing in etc
 

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Discussion Starter · #29 ·
Well....... Just took this thing apart and found bunch of surprises. Found out this has hydraulic lifters with a solid tappet cam. Does not have eagle crank and eagle rods and does not have 11:1 pistons. Also just found out this is a 327 not a 302. I'm pretty pissed right now but I'm replacing the cam with a hydraulic roller cam entire kit 510/520 and leaving the new 750 quick fuel carb. Thanks for all your advice and beware of what people say are in the engine when buying a car.
 

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Thread is 7 years old and the OP is long gone.
 
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