Speed Talk

by **mikes** » Mon Sep 17, 2007 8:04 pm

Hey all, working on a normal aspirated sbc with a holley 650 dp that while idling, burns your eyes right out of your head. But heres the catch, it also has a wideband o2 sensor thats reading 13.3 arf. Whats up with this?? This carb was suposedly done by some pro with screw in air bleeds etc etc. The float levels are spot on, there is no dripping boosters, I can adjust the idle mix screws in and the engine will start to loose rpm...Im not really sure what im missing? It has a fairly lumpy cam too. Thanks for the help!

by **MileHighMan** » Mon Sep 17, 2007 8:19 pm

mikes. Sounds like too much initial ignition timing. Good Luck. Dan.

by **mikes** » Mon Sep 17, 2007 8:21 pm

Hi dan..that would cause this eh? it does have its timing locked out at 38 degrees. I also edited my origanal post with more info. thanks dan!!

by **Unkl Ian** » Mon Sep 17, 2007 8:27 pm

Short pipes ?

by **mikes** » Mon Sep 17, 2007 8:29 pm

Hi, it has full length headers with 3" duals that dump just in front of axle...

by **MileHighMan** » Mon Sep 17, 2007 8:30 pm

mikes. try retarding till your tears go away. It's free. Good Luck. Dan.

by **clevo** » Mon Sep 17, 2007 8:31 pm

Mikes
The 13.3 Afr is rich for idle, i set most engine idle Afr from 14.5 to 15.0 keeps the plugs clean . Flat out rpm the Afr is from 12.50 to 12.80.
:wink:

by **mikes** » Mon Sep 17, 2007 8:34 pm

Hi, what would be the best way to lean this out? open the idle air bleeds or look into the idle feed restrictions? I believe they have not been modified.

by **MileHighMan** » Mon Sep 17, 2007 8:39 pm

mikes. The only thing I would touch is your a/f mixture screws, or your base ignition timing. Good Luck. Dan.

by **clevo** » Mon Sep 17, 2007 8:43 pm

Adjust your idle mixture screws :!:

by **mikes** » Mon Sep 17, 2007 8:45 pm

I did and the engine will drop rpm and i can keep going till it dies so I know they are working...

by **MileHighMan** » Mon Sep 17, 2007 8:48 pm

Vacuum Leak. Dan.

by **automotive breath** » Mon Sep 17, 2007 8:49 pm

Slow flame speed due to residual gas from camshaft overlap. How much
overlap? What ignition are you running? Normally a good capacitive
discharge ignition system eliminates this.

by **mikes** » Mon Sep 17, 2007 8:51 pm

hmmm, it pulls 9.5-10 inches vac. I will go around with carb cleaner to check better....

by **MileHighMan** » Mon Sep 17, 2007 8:53 pm

I'd slow your timing to 16-18 at idle Max. Good Luck. Dan.

Speed Talk

Why does this car burn my eyeballs right out of my face??

Why does this car burn my eyeballs right out of my face??

Eyes Burning

locked out

Tears

Eyeballs.

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