Running Too Rich After Rebuild

grumpyvette

grumpyvette

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HOWS the new engine treating you DORIANL ?
I assume your thru with that oil pressure issue?
anything else?
does it run good now?
 
So far, the exhaust is shutting up (took it for a spin today) and oil is looking good!

Fore some reason I am running real rich! I wonder why? Is the belt so worn it is slipping and leading to a rich condition? Is the filter dirty??? The new extra deep pistons? I am going to have to take this thing to a dyno. First need to replace that belt and find a computer that I can program the ignition with + an adjustable carb plate.
 
both more fuel and retarded ignition timing make the plugs read a bit rich so verify the ignition timing curve as a first step,
Id suspect the carb float levels or the carb needle & seat valve are either adjusted wrong or defective or the fuel pressures too high, if you have a fuel pressure gauge and regulator ID check that, and make sure its no higher than about 5psi at the carb inlet port.
once again I wish we were neighbors as stuff like this is usually easy to isolate and correct if a logical step by step approach assuming Everything's potentially defective or badly adjusted is used, during testing, until you verify its correct
I recently had a guy hook up a FUEL PRESSURE regulator using the wrong ports, he was 100% sure it was correct.....it was such a simple thing to fix once located but it took several days assuming it was a carb or ignition related issue before he broke down and started testing from scratch, it took less than 30 minutes after that to locate and cure the problem, he was not alone all of us at one time or another ASSUME we have something installed correctly or adjusted correctly when we really don,t
 
There are giant clouds of rich smoke coming out the tail pipes. For safety reasons, I did back off a few degrees at WOT. The car DOES feel sluggish. It needs a dyno.
 
DorianL said:
There are giant clouds of rich smoke coming out the tail pipes. For safety reasons, I did back off a few degrees at WOT. The car DOES feel sluggish. It needs a dyno.
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Dorian....a dyno is for tuning an engine, not fixing problems. It sounds more like a problem with the fuel system, not something that needs tweaking to make it right.

A dyno would be an expensive route to fixing this over rich condition......just my two cents worth.
 
Oh, I'm convinced this is just a tune issue. I got my dual wide band O2 to get me ball park, then dyno!
 
Ok, it's just that giant clouds of smoke don't sound like a tuning issue. Let us know what happens.
 
All that I know is that, before I rebuilt, the secondary jets used to be too small until I took the biggest pair from the box and carefully drilled them out.

Since, I have rebuilt the short block.

I was indeed getting leaking primaries till I replaced the needles and seats.

I know that the pressure is spot on because I ran without the boost referenced fuel pressure regulator and... I quickly ran out of steam! So a few PSI of boost would overcome the pressure in the bowls.

Only other things I can think of... I dropped total advance from 35 degrees to 30. The pistons are deeper. And the supercharger bel is quite worn...

You don't think smaller jets + more advance is going to clear this up?
 
BTW, I just got myself a good knot in my calf from a cramp after stretching... go figure!
 
DorianL said:
All that I know is that, before I rebuilt, the secondary jets used to be too small until I took the biggest pair from the box and carefully drilled them out.

A photo would be a big help here. What I envision when you say "Big Clouds of Smoke", maybe totally different from your vision. If it's not dangerously lean, try going back to the largest jets that are undrilled. Do you still have alot of smoke coming out the exhaust ???

Since, I have rebuilt the short block.

I was indeed getting leaking primaries till I replaced the needles and seats.

Is this something you just fixed, how much did it improve ???

I know that the pressure is spot on because I ran without the boost referenced fuel pressure regulator and... I quickly ran out of steam! So a few PSI of boost would overcome the pressure in the bowls.

I will have to take your word on this, I have Zero knowledge in this area.

Only other things I can think of... I dropped total advance from 35 degrees to 30. The pistons are deeper. And the supercharger bel is quite worn...

If the belt is causing a problem, then it's going to be impossible to trouble shoot until the blower drive is working correctly.

You don't think smaller jets + more advance is going to clear this up?

This is what I would consider a tuning issue and once the items above have been confirmed/corrected, then this might work. One question I have is......does it run too rich at all speeds or just idle maybe......need more detail really.
Click to expand...

What changed so much after the rebuild that would cause such a big difference in the A/F ratio ??? Think !
 
Hmmmm, runs rich when secondaries open up... I can see smoke clouds in rearview when I speed away.

Hmmmmmmmmm...
 
These are not GIANT clouds of smoke. It just looks like puffy clouds from being rich speeding down the track.

A couple of months ago the primary boosters were leaking to the point it wouldn't hold an idle. I replaced the neeldes and seats - problem solved.

Fuel pressure is fine.

Only thing really is the jets that I know are ginormous... I dialed back on ignition timing and finally the belt is very worn.
 
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