Needed: Holley carb tuner in Central FLA
I'm looking for someone who is knowledgable in Holley carbs to tune my combo,
Needing help with fine tuning my carb, I'm no expert, and before I mess it up to where I cant drive the car. I have a 383 stroker that was built by T&L Engine Development, a little about the motor, it has a hydraulic roller cam, was a custom grind, spec'd at 236/242 @0.50 .555lift, (only info they provided) Dart Iron Eagle heads, Edelbrock RPM airgap intake, 10.3-1, it dyno'd at 486hp @ 5800, 478tq @5100, idle at 950 with 9"vac, 12* timing with 32* @3600, the engine is in a 84 camaro Z28, roughly 3400lbs, with a built 700r4, 2600 stall, 3.42 thru a 7.65 10bolt rear,
My problem is I have the off idle bog when accelerating, carb specs from AED, 70 primaries, 82 secondaries, powervalve 4.5, primary squirter .031, secondary squirter .035, I have been searching/reading up on all the info that I can find here. I adjusted the timing recomended by AED, to 18* and 1000 rpm for idle, but I still have the bog, my vacuum is @ 8-10" at idle, in gear it drops to about 5 and flucuates to 8-9", I did the easy cruise and monitored the vacuum at a speed of 30 to 40 with a very light pedal to maintain that speed and the vacuum reads 12-15", the engine will load up pigrich while stopped, fuel pressure at the fuel log is 6psi and sometimes fluctuates to 5psi, mechanicl pump, and the level is barely right at the site hole, and yes it has a primary powervalve a 4.5, the secondary is blocked off, the MSD diz has the black bushing, & 2 heavy silver springs, have adjusted the timing to 18*, and according to MSD's website, that gives me a total of 36* @ 3500, this helped very little, the bog off idle is still there, and any time I stomp the loud pedal while cruising it has a slight hesitation.Once the motor clears it's throat, it runs like a raped ape.
I tried adjusting the idle up, but in doing so I cant adjust the idle adjustment screws, any suggestions before I totally screw up the adjustments.....
The torque converter is wrong and the distributor advance curve is wrong.
Get a 3500 stall converter based on a 245MM converter case diameter with full functional lock up.
What you got now is a 12" gm converter that has been tweeked to raise the stall a bit. (all they do is bend the fins in the stock 2100 stall converter)
Your motor requires a real high perf high stall converter.
Recurve the distributor for 24-26deg base timing at idle and 36deg max mechanical advance. That means you have to limit the advance to 10-12deg.
You cannot do this with just a advance bushing swap. you have to modify the mech advance stop.
26 base at idle 36 total then 12deg of vacuum advance for cruising.
Vacuum advance should also be limited to 10-12deg.
The increased idle base spark advance allows you to close the throttles down to the designed idle sweet spot.
Remove the carb, flip it over and reset the throttle blade / idle fuel transfer slot expose at idle. Both pri and sec should be about even .030" ish slot exposure. reinstall
Make sure the pcv is hooked up and functional.
Install fresh spark plugs. it will now idle cleaner in gear and not load up.
If your AED carb has screwin type air bleeds the idle air bleeds may need fine tuning. Use a AFR gauge/o2 sensor to watch the idle and off idle afr.
A very small size change in the primary idle air bleeds makes a big difference.
get it to idle near 14.7:1 with the gauge. The just off idle low rpm cruise should be close to 14.7:1 also. This is when the idle fuel transfer slot is working. At about 30-40mph part throttle driving the primary main jets are working. As you step into the throttle more the power valve opens.
You'll see that point by watching the AFR gauge go power rich.
You can use more rear gear. (4.10's) effectively 2.87:1 in OD witht he th700r4
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