Thread: 4 bbl size for a 302

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It looks like I am going to pull the intake on the low mile 302 to replace some lifters that are noisey after setting for 30 years and since the intake is off I am thinking about putting on a 4 bbl,what would be the ideal size and brand for a 302. Jeff

Since a 500 is the proper size for a 350 (I know just about everybody runs a 600 or bigger, but it is overkill) I would suggest that you not get anything larger than a 500. A 600 would definitely be two much carb.

I still like Denny's formula that he posted a while back, cubic inches times 2......

On my 302 powered '27 I'm running two 500 cfm edelbrocks. On my Jeep truck (with 302 Ford) I'm running one 600 CFM edelbrock.
The two fours actually aren't too bad, but the 600 on the truck is perfect. Just changed plugs after 3 years, perfect color, and good response. I have it on an edelbrock performer intake.

As for brand, I subscribe to the theory "Holleys will win on race day, but Edelbrocks will get you home." I have run the 2 four setup for 12 years, in pouring rain, numerous times, and they just keep on running.

Just my opinion.

Don

Don,

Are your two 500 quads running progressive linkage or straight linkage? If progressive, are you primarily just on a single carb until you get your foot into it? Or are you running both carbs at the same time?

Not really a silly guestion. I have three deuces on my Olds engine and they are currently set up for straight linkage. Let's not talk about mpg, that just sickens me.

Progressive linkage? We don't need no stinking progressive linkage !!

No, actually both are hooked up to open exactly at the same time, straight linkage.
It is a mild 306 with early heads with Chevy valves, 9.5 compression, and a mid range Crane cam. The carbs are mounted on an Offy low riser manifold, and I never had any bog or flat spots.

Everyone that saw it thought it was overcarbed, and it probably would have run better with one, but I wanted that look, so that is what I did. Fuel economy was about 20 MPG.

A friend of mine has a '29 roadster with a 302 with a two-four tunnel ram. He wrestled with Holleys for the longest time and then ordered two Edelbrock 500's. He later told me he bolted them on, turned the key, and had to sit down in a chair and figure out how the heck the car was running so well, and he hadn't even tuned the carbs yet. He had ordered a few different jet sets to install, and never needed them.

I'm just a multiple carb kind of guy, and have always put trips or 2 fours on every car I have had. But you are right about gas milage.

Don

"Progressive linkage? We don't need no stinking progressive linkage !!"

Way to go, if you're going to mount them then they need to used.
20 mpg, hell I don't even get that going downhill in neutral with a 40 mph tail wind. The BB Olds (original 371cid) with the J2 option on a great day will only get 12, but on average it's more like 8 mpg. Could be the three old Rochester 2g's on the Offy manifold, or could be the lead footed 59 year old teenager behind the wheel!

I have been considering replacing my Edelbrock 600 and Torquer manifold on my 34 Plymouth with two Edelbrock 500's on dual quad manifold. 34 now gets about 12 in town and 17 on the highway, figure the dual quads probably won't dent it much more. Besides the next step after the dual quads will be the huffer if I can sneak it in without my wife knowing it.

Thanks for the good news about the Olds and trips getting that milage.

I'm building pretty much the same setup for my '39. I have a mild 30 over 394 with the same Offy intake and 3 rochesters you are using.

I guess it is time to order that 15 gallon moon tank to replace the 10 gallon one I have now???

But, don't you love them Olds??? I grew up shoving Olds engines into any car I could get my hands on, and they were THE ENGINE back then. They are still my engine of choice for old timey rods.

Don

I get concerned sometimes taking the Olds on trips, not because of the mpg, but because of the engine and tranny (original Jetway Hydramatic). Not parts you can find at an AutoZone. But we use it because it's fun. Have taken it to the Turkey Run in Daytona twice and may do it again this year if gas stays below $3 a gal. When I first got it family members tried to get me to buy a 400 gal tank on wheels to tow behind it. Probably would be good for the Daytona trip.

You are so right about the old engines. Getting rebuild part is getting more difficult but it can be done. A friend who had a period perfect original 57 J2 ragtop needed a new crank and had a difficult time getting one, but finally did. He rebuilt the engine then sold the car for $54k. It was a beauty.

One of the car clubs up here has a old style front engine dragster powered by blown 394. Quite the screamer.

Good luck with your engine build, it will be good to see the car when done. I posted a pix of my Olds and engine in my gallery, in case there were some youngin's on here that had never seen a real engine.

20MPG?!?! holy geebus..... i'm happy if i pull over 9 in my mustang with a 302... then again mines a little built up, got some 69 HO ported and polished heads with 351 valves, roller rockers, radical cam, RPM airgap intake, 650CFM edlebrock carb.... i could probably pull more, if i could ever learn to keep my foot out of it

It really loafs at about 2500 Rpms going down the road at 60 MPH. 390 gears, but 30 inch tall rear tires and a 3 speed stick.
Plus, being chopped and channelled gets it out of the wind pretty well.

Probably weighing less than 2000 lbs helps, too.


Don

By the way, I think fastback Mustangs like yours are the best body style they had, even better than the convertibles.

Originally posted by Itoldyouso

By the way, I think fastback Mustangs like yours are the best body style they had, even better than the convertibles.

i agree very much so with you on that... thats why i got the car.... i decided that the 66 mustang fastback was probably one of the hottest small block only muscle cars you can get... and so i bought it... everytime i go anywhere i always have offers on my windsheild for it offering $20k plus.... i only paid $8k plus another $5k in work on it... but what can i say... i love it

I JUST REMEMBERED A FORMULA PROVIDED BY ROD AND CUSTOM MAG :TAKE THE CID. X MAX RPM YOU WILL REACH, DIVIDE BY 3,456 EXAMPLE 350 X 6000 / 3456 = 608 CFM

Then throw this into the calc's......... Fuel that takes up space and how about a mess of annular boosters to atomize all that fuel really well but they are really taking up a lot of space in your 750 cfm carb......

What you wind up with then is about 600.

Gotta remember them magazine guys are selling something.