viergutz2

Alright I need some more advice. I have a 5.3 with a larger cam and valve springs and a 750 proform. It seems to running extremely rich, yet my AF gauge says different. the gauge could be wrong because it still has open headers which on Thursday that will be complete. But I guess I don't understand why it is smoking so dang bad. You literally cant be in the garage for more than a couple minutes of it running. I am hopping to rectify the problem over the weekend since it is finally warming up and the salt on our great northern Minnesota streets is going away.

Ideas from anyone would be great. I have tried adjusting the timing and adjusting the idle screws but nothing seems to help.

89gmcs15

iTrader: (7)

Your open headers are more than likely letting in oxygen throwing off your wideband. Get some pipe sfter your header then check your gauge

viergutz2

Thursday I will have the exhaust on, but is it normal for it to be smoking so bad. its not an oil smoke. It seems to be a running rich smoke and smell.

ZONES89RS

iTrader: (25)

Probably just pig rich. You will see once the exhaust is on with the wide band.

Pop N Wood

iTrader: (1)

If you have just been running it in the garage you may want to clean the plugs before you take it out for real. They can gum up pretty quick running like that.

LXguy

iTrader: (5)

Four corner idle? How far out are the idle screws?

Can you see fuel dripping out of the boosters?

Transfer slot set correctly?

Fuel Pressure?

89gmcs15

iTrader: (7)

Dont worry about any troubleshoot tuning with your wideband until you get your exhaust done. Your just going to chase your tail watching the wideband.

You can however get it running close by not using the wideband.

If thats what your after (honestly a waste since youll be changing it all again with the wideband) post up your carb settings now and we can possibly assist you in gettin it closer

viergutz2

Alright, Exhaust is on and I even got it so it doesn't smoke me out of the garage now. Ended up turning the idle screws in until they where about a half turn out from seating. Now at about 1800 rpm I end up going full lean on my afr. I have tried changing the PV all the way from 4.5 to 3.5 and 2.5 but that really didn't do much. any Ideas.

krochus

iTrader: (1)

Going down on your PV number is taking fuel away not adding as you're lowering the vacuum level at which they open moving the enrichment closer and closer to 0 vac which is WOT essentially.

When is the carb leaning out? At steady cruise or WOT ?

viergutz2

on a steady cruise.

krochus

iTrader: (1)

The power valve will have nothing to do with that. Nor will the main jets typically below 2500rpm or so.

1800 steady cruise should be all idle circuit. How much transfer slot do you have uncovered on the primaries with your idle speed set?

My hunch is you've got too much slot uncovered and you are pulling fuel through the transition circuit at idle (your mixture screws in so far is a clue) so when you give it a light bit of throttle cruising along the idle circuit has no more fuel to give hence the full leanout

viergutz2

Well, I pulled the carb and checked the slots to see if there was to much showing. It looks like there is about .020 showing. I went back to the 4.5 PV also and still nothing. would it be worth going to a larger number PV yet.