Thanks for all the replies. I know I can get it to pass on HC's with the jet and rod change. I'm just not sure if I can lean it out enough to get it to pass on CO%. I do believe that here in CO, the vehicle just has to pass at idle or pass at 2500 RPM on CO% to pass the test. I do not believe it has to pass both at idle and 2500 RPM for that part of the test. Has anyone tried putting Iso-Heat in to get it to pass since that is basically just alcohol?

Yes it does have the big 351C 4V heads on it and a cam, but it has a Edelbrock Performer intake for the 400cid on it. Which that intake is acting as a restriction in the air flow and the cam is a mild/stock replacement cam from Edelbrock.

Jakehan - I think i will try that as well.

 

Lol why were you sticking your face that close to the exhaust?

 

My first suggestion is to move. But if that is not an option, then try a 2bbl. You can get a 2150 from Ford Truck Carburetors for $180. A 2bbl - 4bbl converter is $30. Or find a used 2150 and rebuild it, should have less than $50 in it. Or put your carb on CL to trade for a 600cfm 4bbl. As stated by a bunch of folks here, not sure you will ever make the numbers with a too big carb on it.

 

I had an engine with a similar setup. 351c 4v edelbrock, intake, aluminum heads, long tube headers, large cam etc. It had a 650 edelbrock carb on it. Like most said its probably the size of carb. The 2bbl ones that are stock for the engines are cheap $150-200 compared to a new 600-650cfm 4bbl. That would probably help. Nut sure about much else. Here in Ontario old vehicles don't need to go for e test.

Reman stock 2bbl $200 https://www.summitracing.com/parts/u...view/make/ford

 

Thanks again to everyone for the replies and input. Thought I'd post an update. Several people seemed to be interested if it will pass. I decided to change the jets and rods in the carb. I changed the metering rods to 071x047, left main jets at .104 and changed secondary jets to .098. I also advanced the timing a few more degrees, set idle at about 950rpm, put the mixture screws at 3/4 of a turn out from fully closed, have 15hg at idle and added some Iso-Heet to the gas tank. The secondaries are still disconnected.

I took it in for another test and got the complete opposite of what I was expecting. I'll give prior results first as a comparison.
Previous test:
HC PPM: 2500 RPM - 347.2, Idle - 498.2, Limit - 400
CO%: 2500 RPM - 7.82, Idle - 5.86, Limit 1.50
Today's test:
HC PPM: 2500 RPM - 701.8, Idle - 621.1, Limit - 400
CO%: 2500 RPM - 0.28, Idle - 0.21, Limit - 1.50

As you can all see, It is now running too lean with the 750 carb on it. This result was much to my surprise when I got it. I was expecting HC to pass and CO% to still be high or just barely passing. I will soon (within the next couple days) hook the secondaries back up, turn the mixture screws to 1 1/4 turns out from fully closed, retard timing a couple degrees and go get my free retest and hope that is the last test i have to take for at least a year,.

 

Burning eyes smell is not rich generally, it is high HC, the product of incomplete combustion more often caused by a lean condition.
If you live where strict emissions standards are in play, you can't run huge carbs and lumpy cams. Get used to it. Have a good tune up shop tune your engine on a 4 gas analyzer, there is no guessing game that can even come close. Even with the mods you have, you should get under 4% CO and 500 ppm HC, although I don't know if that will get you legal.

 

So...you are thinking that you can satisfy an emissions test with all of the equipment that was designed and installed removed, to get the engine down to the required emissions specs, and you are doing this with an engine that has been modified in a general anti-emissions direction?

Seems plausible.

 

Yes I think I can. Most of the emission equipment on vehicles is a joke any way. The emissions equipment on most vehicles restricts and hinders performance so much that it makes them run bad. We will once I take it back how it does. At this point I'm fairly confident its just down to getting the mixture screws and timing at just the right spot. I'm kinda on a mission to show that this engine with these mods, large 750 carb, no emissions components (except 1 cat converter which is needed to pass the visual inspection) can pass the test within the limits allowed. Which, if it does, will support my theory that emissions equipment on cars is no more than a government gimmick for them to get more money.

 

One thing about those idle mixture screws, they are precision cut to trim out the amount of fuel at idle needed for a particular engine. About a 1/16 of a turn will move the AFR a whole point so it's amusing to hear people say "Oh, they are about 3 turns out."

 

Yeah, right. Let us know how that works out.

 

When I had my '65 Coronet and lived in SLC where emissions testing was required I passed emissions every year. I drove past every station! Woo! Heck, I didn't even legally need seat belts!

 

Honda CVCC engine. Very trick in it's day. Passed the government standard with zero add ons. No cat. No air injection. No EGR. No computer. Naturally clean. It used a unique 3 valve head to get there. It basically had no "emissions equipment", and yet the government had no problems with it. You are not sporting anything like Honda's CVCC head. In fact, you are totally in the other direction.

As I said before, good luck.

 

High HCs is unburnt fuel. You took it to the point of getting a lean misfire at idle is my guess.


Is there any ability to register the truck as a vintage / antique and bypass smog regs? I had a helluva time with mine back in October until I had some carb work done on my 2150, but eventually got it through in good shape. You have a lot of go fast pre smog parts on there that might not ever pass no matter what you do. Maybe consider an EFI kit?

 

You want full atomisation and a complete, even burn to pass emissions of any sort. Down here in Australia we got Cleveland engines from 1970 through 1985 model year so we live and breathe them.

The Performer intake will help you, being a dual-plane, but the biggest killer will be the cat converter... why don't you just get a pair of aftermarket 100 cell cats and install them after the headers? This will help a lot for any sort of emissions testing.

If you want a quick, cheap fix then reset your 750cfm Edelbrock carburettor to factory settings, remove it and put it back in the box. Now fit a 350cfm Holley two-barrel and set it to factory settings - 60 mainjets and 8.5"power valve. Check the float height and idle screws are to factory settings also, this is crucial. You should pass due to the much increased vacuum through the carburettor and subsequentially better fuel atomisation.

Now after the test refit the Edelbrock and keep the 350 until next time you need testing... although this is most likely illegal (state dependant) and you may get caught out with fines etc.

Probably not the advice you wanted to hear, but it will probably help.

 

I was able to finally make it back to the emissions place yesterday. I wanted to get there much sooner than that but just didn't work out. First off, I want to thank everyone that gave me positive feedback and suggestions to try. Second, I wanted to post my results from yesterday so that everyone that was curious if I could get it to pass and for those nay say'rs that basically said I had a better chance at winning the lottery could see what my final out come was.

Firstly I thought it would be best if i did a recap on the modifications that are done to the truck so that everyone does not have to scroll back through all the prior posts to find it.
Engine Mods:
Stock air filter housing with air filter about twice as tall as standard air filter, Edelbrock 750 CFM 4 barrel carb, Edelbrock performer 400 intake manifold, 351 4v Cleveland heads, stock 351 4v Cleveland exhaust manifolds, single exhaust (modified y-pipe to adapt to cleveland manifolds) with Flowmaster muffler with 3in piping and turn down tip off back of muffler, 1 Magnaflow cat converter (required to pass visiual insp), gutted air injection pump (had to gut pump because the cleveland heads do not have the air passages in them, so the pump is just a dummy to pass visual insp), mild Edelbrock street/strip cam, full MSD ignition (6AL controller, blaster 2 coil, weighted advance distributor (non-vacuum advance)), 8mm plug wires, Motorcraft platinum plugs, 180 degree t-stat, EGR removed, thermatic system removed and Mallory fuel pump.

Adjustments/things I did to get the final calibration:
87 octane fuel (mid grade here, we are at a mile high above sea level), 10-12 degrees of timing, leanest jets and rods in 750 cfm carb per the Edelbrock tuning guide, disconnected the secondaries, getting about 15 in vacuum and about 860 rpm at idle.

Now the trick I used to get it all dialed in because the traditional method of tuning it with a vacuum gauge and tach just weren't doing the job:
Purchased a wideband UEGO O2 sensor/gauge kit from AEM, installed it and tuned the truck that way to get it as close to the stoichiometric ratio (14.7:1, which is 14.7 lbs of air to 1 lb of gasoline if you didn't know) that I could for before cat converter measurements.

Now as a comparison, here are my previous test results:
HC PPM: 2500 RPM - 701.8, Idle - 621.1, Limit - 400
CO%: 2500 RPM - 0.28, Idle - 0.21, Limit - 1.50

Now attached below is a picture of my final test results from yesterday. Thought a picture would be best to try and limit anyone saying that I just made the results up:

So as you can all see, even here at altitude and with those anti emissions modifications to the truck goes to show that with the right calibration and the will to do so that you can make almost, not all cars, pass the emissions test. So as a recap, the only working piece of emissions equipment on the truck is the aftermarket Magnaflow cat converter. All other emissions equipment has been removed or are just dummy parts to pass the visual inspection. Now time to go get its new plates. Thanks again to everyone that responded to my post with positive feedback. Hope everyone has a good and wonderful weekend.