Which carb for my 383/4spd ?

[Ltlgto]

My '69 Roadrunner has a '65 383 and 4spd. in it. I believe it to be stock. It was not running well when I got it so changed all tune up parts, installed an orange box/electronic distributor. Borrowed an Eddy carb while my carb was rebuilt. It ran great the first couple times I drove it, but started running bad again :angryfire: (I have a hard time keeping it running when I come down to near idle) . Could be the distributor moved? Installed rebuilt carb and it was even worse and seems to have no vaccuum. Looking to put a decent carb in it. It is an Air Grabber car so it has to fit under the hood. Should I stick to mechanical secondaries and mechanical choke? Thinking an Edelbrock 600 or 650? Suggestions?

Thanks!

 

[TekHousE]

umm, this might be an obvious comment, but you say you think the dizzy moved? So why not check that first? Then start thinking about new carbs?

 

[Meep-Meep]

Distributors don't move that easily so you might have something else going on.

A 650 will be plenty of carb for a stock 383 (assuming it's stock).

Also, are you running the 65 383 intake? That has, if I recall, the narrow carb pattern with a narrow gasket surface. You might want to check to make sure the carb base is properly sealed to the intake.

 

[bandit]

650 with vacuum secondaries would be my choice

 

[Ltlgto]

Distributors don't move that easily so you might have something else going on.

A 650 will be plenty of carb for a stock 383 (assuming it's stock).

Also, are you running the 65 383 intake? That has, if I recall, the narrow carb pattern with a narrow gasket surface. You might want to check to make sure the carb base is properly sealed to the intake.

Thanks Meep, and you're right, the intake does have a narrow gasket area. The dizzy was tight. I bought a Eddy 600 with mechanical secondaries (rebuilt by local car guru) so I could get it to our local car show. Bought two regular gaskets with a metal plate in between (Edelbrock). The old ones were gas soaked and very pattern worn. Car fired right up and now runs very well again.

I have a chance to buy some 915 heads that have been rebuilt and have the larger valves. Are these too much for a basically stock '65 383? I'm thinking about getting the 915's, a new intake (best kind that will still allow for Air Grabber?) and a cam and lifter kit. Any suggestions? Would probably need another carb after upgrades also.

 

[Meep-Meep]

915 heads would be a great addition especially if the price is right. Hard EX seats would be a huge plus.

If you just want to have fun driving to shows and get on it now and then the 650 will work well. The later stock intake works pretty well but a free flowing aluminum intake like a performer or old DP4B (if you can find a good one) should work better. I'm also taking into account you air grabber clearance requirement.

Cam should be pretty mild. Shoot for something with a lobe separation in the 112 range and 270 deg duration but stay away from the 108 deg cams unless you really want to haul *** and get a bunch of parts to match that cam.

 

[Ltlgto]

So I'm buying the set of 915's for $300. They are recently redone, have the big valves and are ported but he could not remember if they had the hardened seats or not. I will have them added if not. I just ordered an Edelbrock RPM Performer today from Streetside Auto. They were $15 cheaper than Jegs and Summit and had an additional 10% off coupon so $216 shipped. I will be looking for a cam/lifter set next to complete the upgrade. Will probably need a little more carb than the 600 Eddy. Maybe a 650 or 750. Then get my 4 speed redone!

 

[69roadr]

So I'm buying the set of 915's for $300. They are recently redone, have the big valves and are ported but he could not remember if they had the hardened seats or not. I will have them added if not. I just ordered an Edelbrock RPM Performer today from Streetside Auto. They were $15 cheaper than Jegs and Summit and had an additional 10% off coupon so $216 shipped. I will be looking for a cam/lifter set next to complete the upgrade. Will probably need a little more carb than the 600 Eddy. Maybe a 650 or 750. Then get my 4 speed redone!

cool! cant wait to hear about the results!

 

[rumblefish360]

The stock carb on 383's were 1 of 2 IIRC, the Holley and the Carter. The Carter AVS' were a 630 cfm rated unit. The 750 is a nice upgrade along with the intake, air cleaner, headers and a cam.( No need to rebuild it? Good! All the better.)

I would use the Thunder AVS over an AFB any day! The draw back here is the 2 offerings. 650 and 800. If it is to be a Holley, A basic 4150 DP @ 750 would get the nod.