GCSS

I just had the bottom end of my 12v done... 020 new pistons, oil pump, and he set the timing back to stock...
It was at 19.5 advanced before. I have a #5 fuel plate in there now. The truck runs and rives good, it does "Cloud" the morons behind me that like to tailgate...
My question is this.... I am after the best fuel mileage possible..... should I take out the #5 plate and re-install the original one? or....if I leave the #5 plate in there?? If I blow the black when I stomp on it, I will really smoke out the people behind me... I don't mind smoking them, Im just wondering about my fuel mileage..... I have a few options...
#1 put it back to 19.5 advance,
#2 put it at 16.5 or 15.5 like Jim Jessup reccomends ( I had a hard tiome understanding over the phone)
#3 leave it alone with the #5 plate
#4put the OEM plate back in and leave everything factory stock?
please I need opinions!!!!!

Tate

Bump the timing to 16ish, put whatever plate in you want, it doesn't affect mileage.

GCSS

will mpg improve if I go back to the OEM plate?

kawi600

Smoke is just wasted fuel. Also, you never know if that tailgater is a cop.. Ive seen them drive around in unmarked vehicles and theyll come flying up behind you and seem to tailgate while they read your plate and call it in looking for stolen vehicles and such.
A manual 2wd truck should be able to make really good mileage if its tuned right.

Tate

...

GCSS

at 354,000 miles I had an injector go bad.... It basically stuck a little and caused overfueling in #6 cylinder.... result.... melted piston, trashed cylinder wall.
the block still had the original cross-hatch marks in the remaining 5 cylinders and the 5 pistons looked like they were just put in.
They bored the block out .020 over (the minimum available pistons)
New pistons, new oil pump, cam,rod,and main bearings
all done at Hatch Bros. Dodge in Safford,Arizona for less than $3,000.00 parts, labor, machine shop everything.
I live in Ky and had this happen to me three weeks ago ....
Im thinking about re-installing the OEM plate to try to up the fuel mileage.

As for the idiot cop tailgating you.... if you have someone with you, give the moron a brake check. Make sure you are not alone otherwise it's the badge-holder's word against yours. You saw something in the road....

9812vram

The only time the plate makes any difference is at WOT. Otherwize, it's like Tate said: "put whatever plate in you want, it doesn't affect mileage."

I also would agree with the timing - Go 16*.

GCSS

well with the #5 plate in there, it blows the black pretty easy.
I have to ease into it to keep from smoking. when I had the timing at 19.5 it was hard to smoke. a stop on the pedal and the truck would go and go hard!!!!
Tells me that I was getting complete combustion with the timing advanced to that point.
Now...with the timing at stock...(whatever that is...11.5 or 12.5 it smokes easily, and has less power, but still not bad.
I don't know how to change the timing, and will need to take it in to get done.
I can change the plate though.
If I put the OEM plate in, I should get better MPG as the truck won't be blowing the black(unburned fuel out the pipe)
When I first bought the truck, it got 26mpg with the stock plate and the timing at 19.5.
As far as I know it left the factory that way. Some of these trucks had timing changes upon initial startup for the first time due to the assembler failing to wipe the oils from the tapered shaft on the IP. I had one 98 12v that was real bad...it was like driving around with the emergency brake on all the time. Once the timing was corrected, it was a rocket. I wish I could adjust the timing myself, but until someone teaches me, I will just have to pay the man.

9812vram

The fuel plate is the "Full Fuel Stop" plate and only is used under heavy load. I believe all you need is for your AFC to be adjusted. If set correctly, the governor arm will contact the AFC plate in the low rpm's long before it has a chance to hit the fuel stop plate, reducing the amount of fuel injected pre-boost and thus reducing your smoke on pickup.

Get your timing adjusted back up to 16* and then adjust your AFC accordingly. Loosen your AFC housing bolts and pull the AFC housing all the way to the rear of its adjustment - towards the fire-wall. Good chance that will cut the smoke and give your mpg's back. Then adjust the star-wheel accordingly to obtain a doable amount of smoke.

I think the difference you're seeing between the plates is simply that the AFC housing was adjusted correctly before, but was set too far forward when the #5 plate went in.

Tate

Hurray! Someone gets it!

GCSS

no...the plate was untouched. the mechanic put the timing back to factory after rebuilding the bottom end. That is why it is smoking. Before the rebuild when the timing was at 19.5 it was hard to get it to smoke.
In my eyes, it was perfect. well... today I put the factory plate back in and blah... what a pooch. It still isn't bad compared to my Dad's OEM 92. I put the factory plate in and used the guide plate that came with the #5 plate.
I wasn't aware of the AFC HOUSING itself having an adjustment.
I will have the timing bumped up once I get ahead $$-wise. I had a hard hit last couple weeks with the unforseen overhaul and stuff.
For now, I guess I could move the AFC housing....>>> >>>>??? which way???

infidel

It does, about 1/4".
A little goes a long way.
If you slide the cover all the way back towards the firewall you will hate the truck, gutless.
All the way back is only if you need to pass a smog test.