Q: Carb to suit a mild 318 stroker

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dfoyl

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Looking for some options in carb selection for a 318 re-build I am slowly working on. Here is what I have in mind:

318 stroked to 383ci (or thereabouts), mild street cam, late-model Magnum heads, Air Gap intake. It won't see a drag strip, just weekend / fine weather street duty. I definitely want an electric choke. Car is a 69 Dart with a 904, 3:23 gears. It currently is 2-bbl with a 500 cfm Holley.

I'm thinking a Carter 9636 / 625 cfm. Too small ?

Thanks for any help!

Dean.
 
I would go with a 670 street Avenger carb.....vacuum secondaries and electric choke.
 
I just put a 670 Street Avenger on my 360 and love it. I tried a 600, 725 and 750 prior to this carb. The 670 has the low mid range throttle response of the 600 and the top end of the 725 or 750. Plus I picked up 2 mpg over the 600.

Fo my application the jetting was spot on out of the box and the carb only required setting the idle speed and a slight tweak to the choke (needed it to stay closed a little longer with the open plenum intake).
 
dfoyl

Welcome aboard!

At 383 cubes...or so... the carb size should be part of the package. You wrote street duty. From this, I'll assume your not exactly building a high HP engine, just something with muscle.
Can you provide cam specs and tire size?

625 cfm is not to small in one area, but small in another. Stock B block 383's came with small Carters of that rating years back. The early big blocks were not very high in HP. So the smaller carb works great. Once you cam the engine with headers and etc.. stuff, the 383 B engines really woke up well with the larger Carters @ 750 cfm.

You'd be the first to build a stroker without the idea of mashing the pedal, so I'm sure, the engine/car will be put through a few paces and you'll hit the gas hard. Just to get on the Hwy or pass someone on it.


The previously mentioned carb will work well for a mild manored stroker small block. A larger 750 would be preety good for mild racing.
 
Thanks for all the input guys - I've been a member for awhile, but have been reading and learning before jumping in :newb:

>>Can you provide cam specs and tire size?

I haven't looked at cam yet, and that would have been my next question. I'm still mocking up the top end to make sure I have under-hood clearance. Tires are currently 225/14/65 all round, which I'd drop back to 60 profile next time if I stayed with the same rims (I'd probably go to 16" custom made to SBP, but lower profile).

Dean.
 
dfoyl, in your first post you stated you was going to build a 318 mild stroker (roughly 383 cubic inches). I did a little math and I found you would need to use a 4 inch stroker crank with a perfect stock bore of 3.91 to get 384 cubic inches. Is this what you are planning on doing? I think it would be a real nice machine once you get it finished!
 
Dean, part of this puzzle is knowing where you want to be and how you wnt it to perform. On our end, there is a certain amount of knowledge we need to have. Otherwise, the suggestions we give in trying to help you out become general answer with only general info given.

The cam/compresion should have been knowns or the question should have read more like, "Help me build this" 318 stroker with this ........as my goal.

Your changing perameters around, knowing or not, and making it hard to help.

The above 670 Holley carb is a good suggestion for a small cam, under 220 @ .050 duration. But for what engine size, what purpose, what RPM, whats the intended useage of this cam and carb combo. Where will it perform? Road racec, drag race, in a truck?

Thers no one size fit all answer or equation to fit parts together.

Thrashard shows you a good place, Holley, to get a ruff idae on carb size but yet earlier I also said the factory equiped the 383 with the small Carters.
?????????????????????????????????
See how to places equip the same CID engines differently?
Did you know Chrysler also equiped the 440 with small Carters? The 600 or so CFM carbs. Go find a stock as a rock 67 Chrysler Imperial and find a small AFB. (Also note these carbs had no secondary air velocity doors. The engine was so huge that it could suck down the cfms of the small carb without penalty. As a 318 could not do so with a 1150 Dom.)
 
Your tires are very small for this.

What RPM range do you want to drive the car in?
whats it's intended purpose?
Is this made more for cruise and torque or HI end HP?
Whats your thoughts and direction you want to take with this build?
 
Bored&Stroked, yes, 4" stroke with essentially stock bore size or a little over.

rumblefish360, RPM range: I doubt any more than 5000 and that would be only while on the highway overtaking. 95% will be local street driving (not racing), which would be in the 3000 rpm area. Intended purpose: just a weekend driver. Cruising and torque over HP definitely. Cam: still an unknown, but I'd lean towards something that idles well over all-out performance. Compression - 9:1 to 9.5:1. Pump gas (we have 91 octane) or premium (95 octane), premium isn't readily available in smaller country towns so I'd like it to have the ability to cope with 91 octane. It's in an otherwise stock Dart, so standard curb weight. Lmk if I missed any q's.

Dean.
 
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