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

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

When leaning the mixture, the idle goes up
What kind of carb is it :?:

Are you turning the idle screw in or out :?:

by **mikes** » Mon Sep 17, 2007 9:13 pm

Hi, holley 650...turning screws in to lean it...from where the car runs best (around 1 1/4 turns out..) I can turn them in a 1/4 or so till it will start to drop rpm and die from being too lean. Im just into the transfer slot..I will remove the carb to get a better look how far exactly I am into the slot. might have to drill a small hole in the blade if too far?...

by **clevo** » Mon Sep 17, 2007 9:25 pm

Turn the screw out to lean the engine and the idle will come up
Are you using a Afr sensor to adjust the idle ? :?:

by **Eric David Bru** » Mon Sep 17, 2007 9:41 pm

mikes wrote:I also edited my origanal post with more info. thanks dan!!

Do not edit your original post after others have replied to it. Add additional posts AFTER theirs.

EDB

by **Troy Patterson** » Mon Sep 17, 2007 9:55 pm

You haven't yet said what cam is in this thing???? Is it big enough to run 38 at idle?

You need to know the distance into the transition slots (or exposure to manifold vacuum at idle), no more than .040" should be exposed on any transition slot.

Shot power valve or power valve gasket leaking will do the same.

A metering block warped or the mating surface on the center section can allow fuel to be sucked in to the power valve cavity.

Bad metering block gasket.

Too high a float level.

Weak spark.

Wrong cam timing.

Low compression.

It goes on. Need more information. If you want help, don't dish it out piece meal.

Troy Patterson TMPCarbs.net TMP Carbs

by **mikes** » Mon Sep 17, 2007 10:12 pm

hi again, I edited my first post before I had even my first reply but by the time I hit the post button dan had replied. I didnt mean for it to happen that way but I wanted dan to know what i did.

Cam is an old comp magnum 292 . Compression is 9.75-10:1 ish.. a little low for this cam Im sure but cranking compression is 178, pump gas. Ignition is beefed up hei with locked out timing, high voltage coil and better module. If power valve was shot or bad gasket wouldnt fuel drip from the booster? the carb is totaly dry at idle. no fuel above the plates that I can see...float levels good, just even with bottom of hole. I will pull the carb to get exact measurement of transition slot. thanks for the help so far. My main question tho was why the burning eyes with a 13.3 afr...I had that and even less afr's(11.9-12.5) on other engines with no eye burning so I was just kinda curious what might cause that with the higher reading. and no fuel drips from the booster.

by **Troy Patterson** » Mon Sep 17, 2007 10:18 pm

The 292 is a 110 lca isn't it? If so, it's too tight and aggrevated by the low compression. I'd also think you didn't have enough cam to run 38* at idle without paying some sort of price. I'd bet you are building negative torque lower in the rpm range - and you are running a 650? What engine is it, a Buick 231 V-8?

If the power valve or it's gasket were bad, it'd feed fuel into the power valve cavity - which is ported into the plenum chamber. You'd never see it on the engine. When you lift the carb off, it may drip off the base of the carburetor, when holding the carb. level.

I'd think you could get away with 20 degrees or so on initial - maybe a little bit more.

What size engine??? You're starting to pi$$ me off! :lol:

Troy Patterson TMPCarbs.net TMP Carbs

by **mikes** » Mon Sep 17, 2007 10:22 pm

Dont get HOT.... :mrgreen:

its a 350... when the carb is off for the slot measurement i'll check the gaskets and valves...

by **mikes** » Mon Sep 17, 2007 10:24 pm

oh and timing is locked...no advance.

by **clevo** » Mon Sep 17, 2007 10:28 pm

Do you have or use an AFR meter when adjusting the mixtures :?:

by **mikes** » Mon Sep 17, 2007 10:33 pm

hi, yes the innovate wideband is attached to car...I listen for the best running so far but have not watched the afrs to adjust the idle, only after. I didnt realize the power valves would drip into or below the carb...I will pull it tommorrow to check those out. this was on an engine with a mini blower so possibly a valve could have blown because of a sneeze or backfire.

by **Troy Patterson** » Mon Sep 17, 2007 11:39 pm

Oh, here's the deal with the O2 thingy. The more you need one - due to bad a/f ratio resulting in poor combustion, the less accurate an WB02 is.

The O2 don't tell you what's wrong, like is it power valve, high speed air bleed, overlap or the garden hose left running over the carburetor. All it knows is the aggregate result of whatever ills lurk above, and then not all that accurately at times.

Troy Patterson TMPCarbs.net TMP Carbs

by **My427stang** » Tue Sep 18, 2007 5:37 am

Every one I had locked out or a ton of initial was smelly.

Matter of fact, the later the timing, the higher the EGT at idle and it really cleans them up

Maybe run less initial, it wont help right away because there is gas everywhere in the exhaust, but I bet it would clean up pretty well.

by **automotive breath** » Tue Sep 18, 2007 6:44 am

Why is the WBO2 not fail safe? The O2 sensor does not measure A/F
ratio, it measures O2 and reports AFR. In doing this it assumes a
relatively large percentage of the mixture is consumed during
combustion. Here we know that’s not the case, when less of the charge
is burned more O2 remains in the exhaust gas giving a false reading.

The positive side of this is when you get the idle problem resolved WOT
performance will improve. The reason being is the excess fuel you are
smelling at idle is fouling the rings, that black oily liquid on the plug
threads is unburned fuel, this liquid gets in the ring lands and takes
a while to clean up at WOT causing poor performance .

by **Tod74** » Wed Sep 19, 2007 7:47 am

My427stang wrote:Every one I had locked out or a ton of initial was smelly.

Matter of fact, the later the timing, the higher the EGT at idle and it really cleans them up

Maybe run less initial, it wont help right away because there is gas everywhere in the exhaust, but I bet it would clean up pretty well.

Excuse my ignorance...but would someone please explain to me why too much timing at idle will make it run fat? I would think the extra timing would help burn the fuel better...That isn't sarcasm,but a serious question. Thank you