Bog under acceleration

[Dennis Kelley]

Did the car just start doing this? If so you probably have some trash in the metering block. I had picked up something and had to clean the carb. I think if its been doing this since bolted on its a lean condition. I had an extreme lean condition and it would bog like you said. My carb is a BG 650 DP. I jetted up and fixed the lean condition. Wide band on the dyno is the only way to tune. Good luck

Later Dennis

[Cobrabill]

back the bus up.There IS supposed to be clearance under accel pump cams.You need to find out what it is.

[Dennis Kelley]

.015 on the clearance.

[mikey]

Im getting a bit frustrated but I will persevere. Still got the bog. I'm running at 18 deg advance 36 total. Somebody suggested upping it to 20 dont know whether that will make a difference.

BG have suggested bigger squirter - mind you they wouldn't suggest cleaning out the metering blocks would they on a brand new carb

Cheers guys
Mike

[Dennis Kelley]

Hey Mikey,

The suggestion to clean the carb wouldn't hurt. My BG was delivered new with junk between the metering plate. It looked like the metering blocks were not properly cleaned after milling.

later Dennis

[wtm442]

Mikey

What Niles said about the squirter actually squirting gas as soon as you move the accelerator is the most important. It should start squirting IMMEDIATELY.

Regarding the clearance, I thought that Holley recommends 0.050 inch with the accelerator at WOT to make sure that you do not rupture the internals. Maybe I'm wrong????

If that does not cure the bog, then change cams or the cam positions and/or the squirter size.

Hope my memory serves me well, cuz I could not find my Holley book when I went looking. Guess I'll have to buy another.

The best recomendation I ever got was from an old local expert who said "Buy a couple of Holley books and read them at least twice. Then, and only then should you start playing with Holley carbs".

I did that many years ago and I've probably forgotten more than I've learned.