[opeysgarage]

I have a fresh 350 stroked and bored to 383 with edle brock rpm heads and intake manifold. I have a 750cfm edlebrock 4 barrel on it. I am having a hell of a time tuning it in. It idles rough and the idle drops significantly from park to in gear. It also dies or stumbles if I take a hard "u turn like" turn. I tried the instructions from edlebrock but to no good use. By their instructions I have the idle adjustment screws at the front of the carb, turned almost completely in.
If anyone knows anything, please help as soon as possible..
Thanks..
Opey

[ThrouHerEyes]

Could be a break or hole in your muffler or exaust.. my fried's 240sx does the same and it ended up being a break in the welding to the muffler.. start it up over some sand or dirt and look under the car or have it in a driveway and get on the ground if you see that there is air pushing the dirt/sand or feel heat or air from under the car that is your problem...also if you can smell the exaust fumes inside while idleing that is another sign

[woundbroom]

opey,
I have a 750 edelbrock in my garage (notice location) and cant figure the damn thing out either. I reset the floats, changed jets, changed metering rods up and down and mine did the same things yours is doing.I paid near 400 for the carb and set-up kit to no avail.. Checked on line about the carb and we are definitley not alone with these problems. Steve

[DOUBLEDICK]

On my 750 I had a hard time dialing it in.I finally put a vacuum gauge to th manifold And found I had to go to the lighter springs under the metering rods as it would not drop into the lean position at idle.I also hooked a tach(my alt. tester has a tach function) to the distributor so I could see the effect of the metering screws as the difference in rpm was so subtle I could not tell by ear.I had a stumble at initial acceleration and it went away when I changed the springs to match my vacuum and adjusted the metering screws.I also had to change to a vacuum advance distributor as my mechanical advance left the timing retarded to far at idle.The vacuum advance has my engine at about 16 degrees at idle were my mechanical advance had me at the 4 degrees of initial timing at idle.Good luck hope this helps you find the sweet spot in your 750.

[MNFatz]

I had alot of problems getting mine setup too. This is on a new ZZ4.

Part# was edelbrock #1411-750cfm.

First of all, this carb is jetted way lean out of the box. Buy the tuning kit.

I ended up with:

mains: .113
secs: .110
needles: 073 x 037

These settings correspond to #21 on the model 1407/1410 chart--off the scale rich on the 1411 chart.

Pump rod in the top bracket hole, silver (8Hg) metering rod springs.

12-14 degrees BTDC
recurved distrib, light springs so you're all in by 3500 or so.
Disconnected vacuum retard.

Still going a little lean around 2000-3000, but comes on hard after that. Might be room to even go up another jet size from there and 'needle out'.

I hope this helps get you in the ballpark.

[97Z28]

this is why i like BG, Holley or demon carbs. i've known way too many people that had problems with edelbrock carbs. And if you say..."well if you knew how to tune your carb better the edelbrock works fine". that is a load of crap. i've talked to a few edelbrock techs that even have problems tuning them.

my advice to you... go to a car show and find somebody with a similar setup as what you have with an edel. carb and talk to him/her about tuning it. or, you could just sell it on ebay and use the money for a new holley or BG.

[Derkyb]

First do you have a stall converter to match your cam? I've had a few edelbrocks on my 355ci one being a large 750. I tuned it to run ok wide open but idle and part throttle was a mess. I finally put on a 600 jetted it up and it runs 100x better. Your not going to be happy until you put on a smaller carb. heres a link with a calculator, I think you will find you need alot smaller carb than you think. http://www.classictruckshop.com/garage/shopmathcfm1.asp

[olescarb]

the edelbrock carbs have a lean off idle problem, i only recommend using a 650 or lower cfm edelbrock on any application because of this but:

the idle channel restriction (ICR) is too small for the idle system so the idle system runs out of fuel flow before you get into the main circuit. look in the carb owners manual and you can see where it is. we remove the brass restriction over the ICR and then enlarge the ICR a few thousands of a inch at a time to make the idle and off idle system more active. this workd very well on the 600 performer and 650 cfm thunder but on the 750 it only helps since the rest of the idle system passages are too small. these changes have been done to the 800 cfm edelbrocks but it is not enough to solve the problem (in my opinion)if you want to see pictures of this the july 2006 issue of Corvette Fever has a article called tuning to perfection with more detail in it.

you can see this lean at off idle condition with tools such as a wide band oxygen sensor based air/fuel meter or a 5 gas exhaust gas analyzer.

i hope this helps henry @ oles carb