750 edelbrock tune question

[1967coronet]

440 motor home engine, stock 452 heads, comp XE262H cam with comp lifters , crane springs.
small tube headers , edelbrock performer intake, pertronix ignition, stock or oem style napa fuel pump,
timing is set at 16* with 35* total, vacuum advance is hooked to manifold vac. vacuum was 13" at idle of 900
rebuilt 750 , 1411 with the stock orange springs and 7547 rods, floats set at 3/8 and 15/16ths, ran like crap fell on its face at 2,500rpm ethire pulling up slow to 2,500 or hitting it from idle, off idle was great. you get to 2,500 and it fell off flat.
This past weekend I talked to a edelbrock tech guy at the good guys car show about it.
{Used a 600 eddy off my 383 to go to the show it ran fine all rpms but way to lean} Anyway the tech guy gave me a set of { pink springs } and a pair of 7537 rods. I didn't change the float settings just the rods and springs and then reset the timing and air fuel screws with the vacuum gauge , now I have 16" of vac at 900 rpm and the carb works great up to 3,800-3,900 rpm pulls like a freight train from idle, {no bog at all} to 3,900 then starts a light surge, never miss fires just has that real light surging but it keeps climbing in rpms and pulling good, feels like it will go onto 5,000 just fine.
Its real close to being set but what way do I go guys ? should I try the stock 7547 rods with the pink springs? or is it possible the 5/16 fuel line and oem style pump is not keeping up. with this mild motor I didn't really suspect the line and pump would cause any problem.
Thanks for any input.

 

[khryslerkid]

I'm running about the same setup as far as the engine goes. I'm running dual 600's with 15 in. vacuum. I had no luck running the vacuum advance off the manifold. It likes the ported better. Check it out with the timing light to see the total. I had surging with manifold, none with ported. I also restricted the vacuum advance to 55* total.

 

[1967coronet]

I'm running about the same setup as far as the engine goes. I'm running dual 600's with 15 in. vacuum. I had no luck running the vacuum advance off the manifold. It likes the ported better. Check it out with the timing light to see the total. I had surging with manifold, none with ported. I also restricted the vacuum advance to 55* total.

Thanks that 35 total number I put on was just mechanical, I never did look at the total with the vac hooked up. I will tomarrow , grab the light and see what it has and switch to ported and try it out before switching anything else on the carb, Its so close to being done lol.

 

[oliver]

I don't have any specifics, but I messed around with my 4011 for a few years and it would never run right. Finally called edelbrock and had an engineer tell me the internal passages are too small for a carb this size to be correctly tuned to higher displacement or high performance engine. I had surging, bog, and transition problems. I kicked it to the curb for an aed built 650cfm Holley. I bolted it on, adjusted idle and idle mixes and it's been perfect.

 

[rumblefish360]

@67coronet , FWIW, use the 800 AVS model.

 

[1967coronet]

Thanks guys, I got a chance to mess with it some more this weekend. I put a allen wrench in the distributor vac can and found it was 1/4 turn from the stop point clockwise. I left my timing were it was but opened up the can setting 1/2 turn and hooked it to ported.
surge is gone up to 4,500 had a couple cars coming my way so I backed it down.
Don't need any driving awards lol.
Thanks again for the help.
rumblefish I will keep that 800 in mind if I have any more problems.