Holley Carb, AEM UEGO Questions?

[F8d2Blk]

Why would I say that? If you don't want to start anything, don't post dumbass shit. Take that shit somewhere else. Later, QD.

It wasn't dumbass shit, it was more or less a partial joke but it is kind of in the wrong forum. But I posted here in hope of some people with Holley carb knowledge.

[quickdodge®]

It wasn't dumbass shit, it was more or less a partial joke but it is kind of in the wrong forum. But I posted here in hope of some people with Holley carb knowledge.

I didn't know it to be a joke (partial or not). And I wasn't talking about your entire post being dumbass shit. Just your "joke." If you were joking, then my apologies. Later, QD.

[AE86Raptor]

If you're running gasoline, stoic is at about 14.7:1 for an N/A engine, which I would try to shoot for at idle. Other fuels have drastically different specs for stoic. At WOT, I'd aim around 13.5:1, any more and you would have black exhaust smoke (if you don't already). I run ~15:1 at idle and ~14.2 at cruise and ~13.5 at WOT.

[F8d2Blk]

All this is great info. I really appreciate it.
Yes the Holley Carb is actually to big for the application. But the actual manifold that is made I think restricts it some more too.
I should be closer to a 300-350cfm but the one I have is 500cfm
I did the formula but don't remember exactly what it should be but I know there are a number of people running the same setup with better gas mileage and performance is still decent.
www. vg30.com

So I finally have it sitting at 14+ at idle
Wide open throttle is anywhere from 12.5-13.5
Partial throttle is the problem it is really rich ranges from 15+ to over 17+ or when I let off the gas.

" IS THIS BAD?"

so I am guessing this is going back to big of jets. Although my chevy guy also gave some advice about changing a cam on the carb to allow the gas to come in later on.
So all was this morning until my fuel pump quit. Can't go anywhere now. Doh!

[AE86Raptor]

The higher the number the leaner it is. It could be alright, do you hear any detonating? How does it drive, any hesitation? When you let off the throttle I would imagine it would jump lean, and then stabilize to something slightly richer, unless it has a fuel cut-out system of some sort (I know most EFI cars have it, even my 86 model, but I'm not sure on carbed engines).

[F8d2Blk]

It hesitates and boggs some. When it hits those higher numbers and wants to die.

[AE86Raptor]

Another thing I forgot about was that you said that your pump went out. If the pump was weak that could have cause the motor to read lean. Get a new pump and start again. But the hesitation would cause those lean numbers.

[DirtyMechanic]

Uh, yeah. It is. Air-Fuel Ratio is defined as the mass of air to the mass of fuel in a combustion process. This is something that is immutable. It is fact; pick up an text on thermodynamics and look it up.




Now, let's actually think about this for a second. Knowing how an AFR is defined means that a 12:1 or 11:1 is really freaking rich. This is not good from the stand point of efficiency, or the chemical reaction of combustion. It's not good because not all of the fuel is being used.

It *is* good from the stand point of not blowing up a turbo charged engine. Too lean of a burn in that engine will cause combustion temperatures to rise; the excess fuel helps to keep combustion temps in the individual cylinders down. In a non-turbo charged application, combustion temps aren't as critical so the mixture can be leaned quite a bit.

I would ask you to stop trying to give advice about stuff you dont know about. but im sure you wont. but im going to try anyways. STOP TALKING!!! you have really no business talking about what A/F raitos should be.

afr for optimal fuel usage and afr for optimal power are often different. most performance related vehicles will run slightly rich to ward off spark knock, and can allow a little more advanced timing. I would imagine 14.5:1 - 14.9:1 at idle, and approx 13.1:1 - 13.5:1 would be close for WOT, N/A. obviously the best bet would be to put it on a dyno and also have a detonation detection device of some sort.


how about you tune any turbo car @ 10+psi at 14.7:1 and lets see how long before it detonates itself to pieces. I generally tune my cars to 11.5-12.0:1 afr in boost and 14.5:1 part throttle driving.

+1

All this is great info. I really appreciate it.
Yes the Holley Carb is actually to big for the application. But the actual manifold that is made I think restricts it some more too.
I should be closer to a 300-350cfm but the one I have is 500cfm
I did the formula but don't remember exactly what it should be but I know there are a number of people running the same setup with better gas mileage and performance is still decent.
www. vg30.com

So I finally have it sitting at 14+ at idle
Wide open throttle is anywhere from 12.5-13.5
Partial throttle is the problem it is really rich ranges from 15+ to over 17+ or when I let off the gas.

" IS THIS BAD?"

so I am guessing this is going back to big of jets. Although my chevy guy also gave some advice about changing a cam on the carb to allow the gas to come in later on.
So all was this morning until my fuel pump quit. Can't go anywhere now. Doh!

dont do anything. what you just said sounds right on. part throttle could be leaner and the off throttle could be richer. but other than that. your good. to help the wanting to die when you let off try riching the idle up ever so slightly. this will help the dieing part.

[StraightSix]

I would ask you to stop trying to give advice about stuff you dont know about. but im sure you wont. but im going to try anyways. STOP TALKING!!! you have really no business talking about what A/F raitos should be.

Really?? Tell me, please, exactly which portions of my post were in any way wrong. From where I'm sitting, you've made an empty accusation since you're unable to justify your opinion. Heaven forbid someone understands the theory behind why and how an engine runs. Perhaps my tone was a bit snide, but the facts remain; anyone who can read and knows a little math can very easily corroborate the information I've presented. So, until you can refute, intelligently, what I've presented don't criticize what I have to say.

[DirtyMechanic]

Really?? Tell me, please, exactly which portions of my post were in any way wrong. From where I'm sitting, you've made an empty accusation since you're unable to justify your opinion. Heaven forbid someone understands the theory behind why and how an engine runs. Perhaps my tone was a bit snide, but the facts remain; anyone who can read and knows a little math can very easily corroborate the information I've presented. So, until you can refute, intelligently, what I've presented don't criticize what I have to say.

stoic means nothing for modified car. and even for a stock car it still means really nothing. for a stock car thats usually where idle is. but idle usualy goes rich then lean so the cats can perform. and yes stoic is where air and fuel combusts to produce the least amount of emissions. but since it goes rich and lean the nox and co go up and down. now with a cat the nox and co are lowered due to the rich/lean change of idle. now for power you never ever use stoic for a tune other than idle.

power for n/a is usualy from the high 12s to the mid 13 a/f. it all depends on the engine and what the specific engine likes. which you will only know if you tune on a dyno to find out where the power is. now for boosted cars the a/f is usualy much richer for safety reasons. which are usualy form the 11s to the low 12s like i said depends on what the engine is and what it likes and where it makes power. but usually tuners go for a richer a/f to save the motor.

like one guy said before you tune a boosted car to a 14.7 stoic that motor will
1: not make any power
2: pop real quick
3: not run

even for a n/a motor 14.7 is not going to yeild you any power. just extremely high EGTs. so there i back up what i say. if you want talk more be my guest ive been in the aftermarket area on the tuning and building said for more than 3 years. may have heard of the shop. Forged Performance