Carbed in MA: Failed Emm(HC:2/1.2 CO:27.37/20) Need tips!

[crazypete]

So I just advanced my timing even more!

You know how the balancer says -10->32 then "BTC ::: E4tE"

Well, I put the timing to between the TC of the BTC...which is about 42-45 degrees and still no pinging!! I advanced it again to the 4 of the E4TE (50-53 degrees appr. ) and FINALLY some pinging.

So I was like OMGWTFBBQ and revved the engine with the timing light on.

AHA!

The timing only jumped about maybe 10-12 degrees. I think the centrifugal advance (the only kind my car has) is stuck or gummed up. I think it might be time for a new dizzy (the vac advance never worked on this beast so this is an excellent time to get that working too).

It's a shame. I would rather have thumped my chest about my "posessed demon car that can run 50 degrees initial timing"

 

[jrichker]

So I just advanced my timing even more!

You know how the balancer says -10->32 then "BTC ::: E4tE"

Well, I put the timing to between the TC of the BTC...which is about 42-45 degrees and still no pinging!! I advanced it again to the 4 of the E4TE (50-53 degrees appr. ) and FINALLY some pinging.

So I was like OMGWTFBBQ and revved the engine with the timing light on.

AHA!

The timing only jumped about maybe 10-12 degrees. I think the centrifugal advance (the only kind my car has) is stuck or gummed up. I think it might be time for a new dizzy (the vac advance never worked on this beast so this is an excellent time to get that working too).

It's a shame. I would rather have thumped my chest about my "posessed demon car that can run 50 degrees initial timing"

If you can find a shop that has a Sun distributor tester, they can test the timing advance for you. Some different springs and maybe a different bushing on the advance stop pin can allow you to bend the timing curve to almost anything you want. My favorite setup for 6O's Olds & Chevy's was 10-12 degrees distributor and 14-18 degrees initial advance. Total timing was 34-42 degrees. Back then, 100 octane leaded fuel was available at the pump.

 

[crazypete]

So I ordered a new accel distributor with easy adjustable counterweights and adjustable vacuum secondaries.

But...

I was thinking.

This advanced timing might be good for reduced HC and CO, right? Nox might go up but it was nonexistant in the last test anyways.

Should I leave the "super-distributor" in for the test? It gives me a lot of extra ping free timing across the entire range.

 

[crazypete]

So it turns out the distributor was the problem. The old 76 granada distributor's advance mechanism no longer worked and the vacuum advance never has worked properly.

Got me a new accel

I can now get about 18 degrees initial before pinging, 40 total and vaccum advance now works. Totally different car.

So I got the jetting "just right" with 2 green bars on my mixture guage and I have one last question before go for a retest.

Should I let the advanced timing try to cover the hc/co with the better burn or should I downjet to get it leaned out? I take it a miss will up the emissions as will a lean ping.

 

[rd]

Yep, a misfire is unburned fuel going to the exhaust, and should be avoided at all costs.

You probably need a good bit of timing no matter what.

I would jet it as lean as it will go, per your meter, for testing.

The other suggestions I have for getting emissions down would be to add a stock 85 style Ford or similar Edelbrock Performer intake that has EGR, hook up the egr, and also hook up the air pump to the heads and to the cats. Maybe install a new air pump, or at least clean the filter on the inlet real good.

You could also try the Holley emission style jets, ie, those with a 2 after the jet number. They are flowed and tested to flow within something like 2% of design, vice a much wider allowable variation on standard jets.

I installed a Holley 8005 reverse idle type emission carb on my 79, way back in 86, just in case I had to get smogged, but I never did. It came with 622 primary main jets. This also had a 2 stage power valve, although I don't think thay would help much.

I think an MSD box would also help.

I would definitely resolve the damper and timing issue, if the dist did not do that.

 

[crazypete]

Thanks guys for hanging in there with me.

I've taken care of the timing issue. It was all in the distributor. It basically was running the equivalent of locked out timing with a small 7 degree mechanical advance. This is why I could take 40 degrees initial timing. It also means I ran the last emissions test at 17 degrees total timing...not good.

I already have the best ignition I can. Crane hi-6 (1200 joule sparks) on an ls-92 coil (their better coil) through side gapped and indexed plugs.

I kinda want to get EGR working but I have no way of controlling the EGR valve. I tried having a continuous open system and the EGR overwhelmed the motor immediately.

Well, when I get home, I'll downjet. I'm worried about stripping the threads on the carb, I've changed my jets so often this past month. But it looks like in MA, your registration now gets revoked after a few months if the car's uninspected so I need to get this crackin.

I'm thinking. Downjet 2 sizes from "2 green bars" to get lean but only on the primary. Leave the secondary alone and put a black spring (stiffest) on the secondary side to take the secondaries out of the equation. Put a 2.5 powervalve so it doesnt open during the test.

I dont have any specialty jets like that. I have a pair of the "H" jets but I'll look into that.....in the end though, the mixture guage tells all, right?

 

[crazypete]

So in the end...its not what you know, it's who you know. They took pity on me after they saw I had failed something like the 5th time and they kept the car overnight so they could "tune it up and get it to pass". I came by the next day and it had a sticker on it. I didnt ask any questions and they didnt offer any explanation.

Bottom line.....if anyone is going to do a carb conversion on a street vehicle
1. Get a 1990 or before. This is the cutoff point for the laxer EPA requirements. I would have passed the first time around if my car was 1 year younger.
2. Get a set of fresh cats and dont use them till the day of the exam. My richer running clogged them up in a week while horsing around. They were nonexistant by the time the 3rd test came around.
3. Stay away from alcohol. It greatly raises emissions! Maybe a little bit helps but even at 25% mixture, it practically prevents combustion. I was choking from the fumes with cats installed at idle.

This whole experience has greatly eroded my enthusiasm about mustangs and car wrenching. Owning this car is just a continuous roller coaster of problems and issues.

So in the end, all the tinkering failed and it all came back to getting help from someone else.

Thanks for hanging in there till the end, guys.

 

[jrichker]

Gald to hear that you got your sticker & can drive the car. Too bad we don't know what was done to make it pass, that could have helped other guys in similar situations.

 

[crazypete]

Actually, it would have passed if I didnt have locked out timing. The numbers were so damn close. And my first tune was "slightly lean" running 87 octane with acetone. If I had a full spark advance, it wouldnt have failed cycles 3 and 4.

The most important thing is fresh fresh cats. Install them literally the night before you take the car and dont drive until you go for the test. Run a good tune and back off 2-4 jet sizes. Get a restrictive power valve and make sure the secondaries stay closed.

Best thing, like I said before......is have a pre 1991 car and then you'll coast right through with your fresh cats.

 

[payupsucka]

Best thing, like I said before......is have a pre 1991 car and then you'll coast right through with your fresh cats.

since when did that do that? i have a 90 and i gotta go on the machine every year

 

[crazypete]

since when did that do that? i have a 90 and i gotta go on the machine every year

hats true but if you looked at the EPA requirements for HC, for instance something something up to 1990 is 1.2 and 1991 and on is 2.0 for limits.

You get laxer standards with pre 91.

 

[payupsucka]

hats true but if you looked at the EPA requirements for HC, for instance something something up to 1990 is 1.2 and 1991 and on is 2.0 for limits.

You get laxer standards with pre 91.

cool i wonder if i will pass with cats but no smog?

 

[crazypete]

cool i wonder if i will pass with cats but no smog?

Nope, most cats dont work without a smog pump. They do make them but they are more expensive and even then you probably want to pump some fresh air down there to thin out your exhuast gasses a bit.