I bought an 87 monte carlo ss stock and removed the computer, installed a summit racing Hei distributer along with a 1406 600cfm carb with a holly intake and ever since then the car has not done burnouts in first gear and has zero guts in second gear. I know the car was clearly faster before switching to a regular carb. The timing is dead on and I bought a spring kit for my distributor which helped so I know it has to be the carb. I moved the accelerator pump linkage to the bottom hole and it helped. installed bigger secondary jets and didn't do much so I installed 73X42 rods and it just ran rich although not slower just richer and smelly. Can anyone give me a route to try on this carb I feel like I am walking blind lol




Btw I cant afford a air fuel meter.

 

Update- I went out and tried 5" orange step up springs .095 pri jets .101 sec jets 70x37 rods and accelerator pump linkage in bottom hole. Car has much more power although it smells a bit rich when u rev it up. If I move the accelerator pump linkage to the middle hole it fixes the rich smell but then the car looses all that gained power. Any suggestions?

 

You say the timing is "good" but honestly sounds like you might have more of a timing issue than a fuel issue. Out of the box the 1406 or even 1405 work pretty well on even a stock 305 or 350. One thing to check is the float level and float drop. Also unless you are at high elevation I suggest leaving the stock jetting atleast initially. You can step up to the 8" step up springs to give a richer/smoother transition to power. On my 1405 I found the out of the box jetting to be slightly rich on my LE9 305 in my 83 G20 van and ended up going 2 steps leaner on the primary jets and 2 steps leaner on the cruise end of the metering rod but kept the same power tip size on the rod. I ended up leaning the secondary side out 2 steps as well.

Now on to your distributor issue..... With a typical HEI providing 20-22* total advance in the centrifical advance you will want your timing to be 12-16* initial with the vacuum advance disconnected and the engine idling as slowly as possible. I put a LB9 from a 1985 Trans Am into a 1984 Elcamino a couple of years ago. The 1985 LB9 is the same long block as a L69. I put an edelbrock performer intake, a non computer Q-Jet on it and a MSD HEI distributor on it that gives 22* centrifical advance. Even with the stock stall in the TH350 in the car and the 2.43 ring and pinon the car runs best with 16* initial timing and 38* total advance all in by 2,600 rpm. It doesn't ping or knock with the lightest advance springs and has smooth, strong acceleration at all speeds. The vacuum advance is connected to manifold vacuum and adjusted to give about 10* of additional advance at crusing speed. At 3000 RPM it runs 48* total advance, running smooth as silk.

 

I don't know the actual degrees the timing is initial due to the tag being missing on my engine so a timing light won't work although I bumped it up until the engine turns over hard and then backed it off till the engine stops pinging at high rpm. I found the best spring combo to be 1 stiff and 1 soft. I tried 2 soft and the engine never pinged but it lost all its power I mean ALL. The car starts runs and idles fantastic its just running rich now that I changed the carb combo to get its power back. Also I forgot to mention that it still has a 13psi fuel pump although idk what effects that would have. Quite honestly I wouldn't mind the rich smell if it was 85-90 degrees out today but its 40 degrees in Rochester ny so im just worried that when summer arrives that it will run really rich.

 

13psi fuel pressure is way to much get it to 4-6. Also if it ran good why did you make the swap? Less power and worse MPG?

 

I bought the car to restore and before I tore her apart I took her for a quick spin with the computer hooked up and I was going to leave it but the vacuum lines were dry rotted and the distributer ended up failing and wiring being old it was just quicker to swap over to a carb. My dad just tested the car with me again and he thinks it runs night and day better now that I jetted the carb so ill just get a fuel regulator and set it to ur specs.

 

Get a fuel pressure regulator on it ASAP. Edelbrock carbs do not like any more than 5.5 psi. Over that and the pressure pushes the needles out of the seats, and can also bend the float arms (which is how the floats are adjusted)

I set all mine to 5.25 psi for eddy carbs.

Best way to pick the correct step up springs is to measure engine vacuum at idle in gear and divide that number in half and use the closest spring to it..

Like if you have say 16" hg vac, use the silver 8"hg springs (in fact that is the biggest they have so use it for 16" and higher vac readings)

If you do not have a vac gauge and the engine is all stock (other than induction and ignition system) go a head and swap the silver springs in as it's a safe bet you have more than 16" vac anyway.

I would also check the float adjustments as well. For years they were shipped out with the wrong float levels..

7/16" at rest and 15/16" to 1" drop measured with air horn gasket in place.

 

You are the 4th rochester area guy I know on this board now. We should get a small meet going maybe mendon ponds park or something. Have some burgers.

 

yea definitely, I didn't know anyone on here lived near me. who else on this forum is in Rochester?