devin1

Hey Everyone,just put a stock 5.3 in my 71 chevelle.Got it started without too much trouble,idles fine,starts great.750 holley,edelbrock intake,edelbrock ignition controller...iknow iknow everyone says they are garbage. When I try to rev the motor slow but steady it cuts out for a split at 2k rpm for a second like a miss,if I rev it quickly it back fires through the carb.Carbworked great on my bbc,jetted it down for the ls.So I guess what I am wondering is it really that bad,the controller that is ,or is there some thing else going on. I checked voltages ,grounds,fuel pressure is fine,new plugs.Am I missing something or is Edelbrock really selling something that bad.

ZONES89RS

iTrader: (25)

I will assume you have a 30 cc accelerator pump and it is a mechanical secondary?

devin1

Thanks Zone,I was hoping you would reply,no it has 50cc cam an yes mech secondarys,jetted it bown to 70s and 76s.Carb worked great ,Should I have the pink wire on the controller run to a relay off the battery?

ZONES89RS

iTrader: (25)

You happen to have a wide band oxygen sensor? Have you tried all the different timing pills?

devin1

Here is the car in question

speedtigger

iTrader: (16)

Which Holley model number do you have? Why did you change the jetting?

devin1

No wideband,yes tried all pills,puton my 850 qft and does same thing,if I hold it at around 2k it will cut out repeatedly over and over,ground is on back of drivers head.
I am going to add another ground,and also run pink wire through a relay directly to battery.Do not think it is carb related but have beenwrong before..lol.

speedtigger

iTrader: (16)

That is a good check. Two carbs same problem sure does sound like ignition problem. By chance did you hook the power for the MSD up to the factory ignition wire? You likely already know this but, pre-HEI models have a resistor wire that must be replaced from fuse box.

ZONES89RS

iTrader: (25)

Totally forgot to mention that, good catch bud.

devin1

Yes it is hooked to the factory wire,My msd6al that I just removed was also wired this way,but it got its main power directly from the battery.This may be an issue?
If I put my volt meter on this wire with key on shows 11.4 volts.
I am going to change this,thanks for the replys,will keep you posted

ZONES89RS

iTrader: (25)

Wire it straight to the battery and see what happens. Should be 12+ volts while not running.

Horsepwraddict

iTrader: (12)

I chased a similar problem for a long time with my s10. Turned out the bolt I had the ground on had a mangled thread. It felt tight with a wrench on it but it was just shy of making good tight contact, it was under the dash so it was hard to see. Had me scratching my head for a long time.

devin1

OK guys do I have egg on my face,sorry Vic.Ran a jumper from pink wire directly to battery,took a little 80 grit to cylinder head where ground wire was attatched...oh man what a difference.
This morning I will go and get a relay and wire that sucker up properly.It was still way rich because my 850 is still on there,but miss was gone and seemed to rev way better,
cant wait for a test drive,only ever drove this car with an all steel 427 bbc and 3800 stall
For anyone that cares,th350 2200 stall 3.42 12bolt posi 5.3 out of 2006 gmc.Ran a best of 11.70 114 with bbc,will be a couple weeks before I get back to the track,and the best part is I hope to drive it this trip and leave my truck and trailer home.
Thanks for all the help guys,it is always the little things that bite you when it comes to building cars...

ZONES89RS

iTrader: (25)

That's good to hear man. Me and many members will preach how important grounds are, but I think the power wiring was the issue. A bad ground can cry these boxes.

devin1

Thanks zone
Yes ,I guess my excitement of getting this running got the best of me,I know
better.
Rewired through a relay,test drive went pretty good feels quite nimble with the
reduced weight on the front of the car.
Still needs some tuning of carb and such,little stumble off transition,squirters may be a little big yet.
Is there a table of the timing curves for the edelbrock box?
May help a little with tuning,running chip 1 which I assume would be the least aggressive,amI correct?
Defenitely a good starting point,so thanks again guys...

devin1

Hey everyone,sorry for the long absence,engine runs great now,went to an edelbrock 750 carb,seems to be the ticket.
Now my issue seems to be drivetrain angle,engine is at 4 degrees at ride height,pinion angle matched,but has a pretty good vibration I cannot seem
to get rid of.
Is 4 too much,cant go lower inthe front because of truck pan and steering linkage contact at hard left turn.
Whaat is everyone else running for angles?
Guess i need to get a f body pan and smaller ps pulley?
Any thoughts or suggestions
thanks

Horsepwraddict

iTrader: (12)

can you raise the transmission mount to get some angle out of it?

devin1

Yes ,I raised it 1/4 inch only changed it less than 1/2 degree.
More would require tunnel surgery,been thinking of that but not there yet.lol