holley carb help

[dust-u]

Gonna remove my six pak for rebuilding/ tuning(running rich) I have 2 carbs to try.. and need a recommendation... 1st motor is 340 plus 30.. 11:1 comp.(maybe 12: 1 its old school) 509 cam 4 sp. 3:91s out back.. looking to use a nice ld340 intake I picked up. carbs are as follows : 650 dp..basically stock. 2nd holley 770 street avenger vac. secs.. what would u run... and why.. I am all ears...:burnout: I have heard these street avengers are problematic.. are they?

 

[Mrmopartech]

Give me a call at the numbers I sent you,mrmopartech

 

[82CRUISER]

I would run a770 with smaller jets and a lower vac power vlv. The eng will run nicer with the larger cfm. The tuning should be done by checking the plugs I am told

 

[EL5DEMON340]

I would use the 650dp. Should be close with the stock jetting or look for about 68 to 70 pri and 75 to 78 sec. May need a bit bigger pri squirter. Use a 1/2" 4 hole phonolic spacer under it. Most Dp will be a bit rich off idle and cruise.

 

[forphorty]

650dp

 

[AJ/FormS]

For street, the DP for sure. It's waaay more funner! You can open all 4 holes at what ever rpm it will take it without detonation.I slowed my advance curve a bit, off the bottom for that reason, with a 2-stage curve. I was able to go back to 3.55s, with no perceptible loss of bottom end as compared to a 750 VS and 3.91s. It lights up the 295's almost right off idle. Whoo-hoo! Yeah I'm a just a punk-kid in an old mans skin! lol
And the Smaller 650 is easier to modulate wheelspin with, which makes sliding around corners a bit more controllable.
My cam is a 230@050fast-rate and I use a 750DP. It has quite a bit more torque off-the-line, then when it had the Mopar 292adv/549. Second-gear Sliding is super-fun

For track work cant say.But the 650 is likely a bit small. Mine made more mph on the 750, but was hard to get off the line without wheelspin.Actually, with 325/50 DRs, it was impossible,on our track, to not light them up. Still went 93/8th.