First79vette

#&^&#$ directions....two ports on the front of my 750 Edelbrock..right now i have the vac. advance plugged into the drivers side. and plugged the pass side. Pass. side says its for idle advance... :confused: idles better in the drivers side. Seems like i'm haveing a hell of a time getting this thing to idle without bogging after warm up decently at a stop in gear, right now it will idle at 900 rpm (not in gear) all day long. I have a new stock fuel pump on and wondering if shes fogging to much fuel in, what is stock pump pressure? I'm rigging up a pressure gauge to check, Edlebrock says it should be in the 5-8 lb range. Man that 3/8 fuel line really bobs and throbs! I'll be checking timing tonight and see if its slipped, I had it set at 12 BTDC befor the inducter fell into the header... :mad have that fixed now.. :banghead: any suggestions? Is that vac advance line plugged into the right port?

Mikeb690

I just went through this on my Q-jet....The guy who had it before me had it hooked up wrong. If you have it hooked up to the port that pulls the vacuum at idle then its wrong. Hook it to the one that is not pulling any vacuum at idle. It pulls the vaccum as you rev the engine, thats the one you want for the vacuum advance.

neverendingproject

depends on your particular engine. near stock , the pass side port. huge cam, driver side.

gravismaximus

i dont have my distribtor pluged into my750 edelbrock. i have it pluged into the intake. am i loosing power this way? or is that just for idle.

BacaBill

I have a '79 w/ the Edel 750 DP also. I'm having, probably, the same problem as you. It stumbles after sitting idle, up to about 2200 rpm. I even bought the calibration kit & jetted it all the way lean. (tried rich first). Even full lean, it's running super rich, almost enough to burn your eyeballs. Oh, the original question,,, according to Edelbrock, EGR equipped, passenger side,,,,, w/out EGR, driver side,, mine is on the drivers side.

AlwaysWave

As I see it.

The initial (at idle) timing is set without any vacuum attached. So why would you then use the manifold vacuum which advances the initial timing once hooked up? Use the ported. The ported is the carb outlet above the throtle plates, in other words, the highest one of the two.

The idle circuit is in use at part throtle as you cruise at lower speeds. At 1500 rpm I'm doing 40 mph with barely a touch on the pedal, and I know the throtles are hardly open and still within or slighly above the transfer slot.

Make sure your carb is setup so that the transfer slot at idle is showing no more than 040" of transfer slot. Set your timing and idle speed adjust with a vacuum gauge to manifold vacuum, and set for the highest reading you can get.

With a bigger carb like the 750, you can lean the idle screws to a lean bog and pick up idle rpm's by advancing the intitial timing more. If your total timing then comes in too soon, you'll have to use lighter distributor weights to correct it. It's a game of trial and error, but you can eleiminate the rich condition.

Also FYI....Edelbrock carbs don't like more than 6 psi fuel pressure. At more than 6, the needls may be overcome spilling extra gas. I use a regulator on mine, set at 5 1/2.

First79vette

I think I got it...But whats the transfer slot? :confused: what is the stock pump pressure? I know it doesnt like anything above 6lbs and dont have my pressure gauge made yet to check, D@%#$n busy day too. :mad I'm going to plug into the pass side and reset timing and see what happens. Glad to see I'm not the only one with this problem. :lol: I think I might have the idle screws open too far too. The other thing too is that I did not put any different weights in the dist. (stock weights) would they be set up for EGR? this engine did not have a smog pump on nor was there

Thanks!


[Modified by First79vette, 11:15 AM 4/24/2004]

First79vette

Made the change... to the passenger/higher port, set the timing at 10 BTDC seems to run a lot better. Idle neutral at about 975 and drops to 725 or so in gear with no bog at full temp.l :yesnod: Hopefully this cures my problem. No more dying at the stop signs. :lol: