I unhooked the 4 wire conector that you on hook when setting the timing, and now the car does not after fire nearly as much? it will still pop here and there but no where near as much or as loud as before? what can I do now? should I bump the base timing up? or should i turn it down, how much either way? it is at 4 or 6 right now? by disconecting the 4 wires what did it do to change it? the car does not have as much power right now so i don't want to leave it disconneted.

Also if I use teh zz4 ecm/prom am I going to noticed a diffrence over teh jet perf lg4 chip? ( I probably would spend around $400 for the kit) thanks

P.S by advanceing th ebase timing does it change the advance also? thanks

 

sounds like it is just running rich... only does it on the jake brake though right?

 

Yeah but it stopped when I took the ecm out of the timing ( by disconecting the 4 wire conector)

 

the 4 wire connector doesn't take the ecm out of the timing. it is a SINGLE light brown/tan-ish wire that you unconnect to set the timing. Typically located near the brake booster or around there.

 

On the carbed cars it is a 4 wire connector, it says it right in the manual.

 

Hummm in my 82 it said to disconnect the single wire.

 

yes it is the single wire connector but if you still have original hood with the emissions sticker it will tell you exactly what to do and what the stock timing is...but i have the haynes manual in front of me and it says nothing about removing the 4 wire connector from the cap ANYWHERE it doesnt even tell you what it is called besides a FOUR WIRE connector so plug that back in

 

Doesn't matter what your Haynes says.

On the carbed cars, you set the timing by disconnecting the 4-wire plug that hangs out of the distributor base.

Which is NOT the one that goes to the cap.

I'm not completely sure about this "afterfire" business. I'm kinda new to this though, only been doing it since the 70s. Maybe I still have something to learn?

Your timing should be set to about 6° BTDC with the 4-wire plug disconnected. LG4 cars usually call for 0° on the sticker, but will run better at 6°. Experiment and find out. There's no "magic" in any particular number; the engine doesn't get out its timing light and check the "number", and then decide accordingly to run however. Just give it what it wants.

It also doesn't change, except for a real slow retard over a long period of time. There's no reason to just be twiddling on it all the time, like there was back in the points days, where it changed as the points rubbing block wore down and needed reset about every oil change.

If it doesn't seem to run right when it's set to the factory spec with a light, then there's a good possibility that the inertia ring on the crank damper (the piece that the moving half of the timing mark system is on) has slipped, and when the light "says" it's at 0° or 4° or whatever, it's actually somewhere out in the ozone. Check to be sure by putting the engine at TDC with a piston stop or something, and verify the accuracy of the mark. They're rarely exactly right, and they're often extremely wrong.

 

I have tried from 0 to 12 and it still does it, I have it at 8 right now, the car runs great, besides this problem,I have one of those damper covers that bolts on the numbers are marked on it.

 

You know, on a carb car you're always going to get a fair bit of "pop and snarl" on the overrun when you lift at high RPMs. They can't shut off fuel flow during overrun like a fuel injected motor can. Now, it shouldn't be so bad that you're afraid you're going to blow the exhaust off the car, but with a loud exhaust it'll sound pretty raucous when you lift.

Now here's one I don't think had been brought up to you before......

EXHAUST LEAKS..... they can make for some NASTY popping on the overrun. You recall I said a carb can't shut off fuel flow during overrun, right? Well, you're going to be dumping quite a bit of unburnt and partially burnt fuel straight out the exhaust on overrun. It only needs 2 things to allow it to ignite violently in the exhaust: heat and oxygen. Obviously, there's plenty of heat from the exhaust valve on out so that really just leaves oxygen. If you're got a leak in the exhaust anywhere forward of, say, about the cat converter that leak will draw in outside air between the exhaust pulses- which has lots of free oxygen in it. KABAM! Bigtime backfires.

 

I disconected the 4 wire conector at the dist (the used to set timing) and the car does not pop on decel nearly as much (barley at all if at all), so what can I do now?timing chip? please fill me in? The poping is alot louder then normal.The exhaust is air tight.
thanks

 

I have the cc carb and dist, could I make some kind of switch that would cut the circuit to the est when the throttle is closed?

what about teh l69 chip, could i get one of them and stick it in my stock ecm? if so what part number do i want? I have a knock sensor and a 5 speed.

Or should I just go with a none cc carb and dist? if so which ones and what do I with all the other sensors and the ecm? thanks