I have figured it out

[bigd65]

All the times i have posted about the truck running rich and then a vibration problem, well i believe i got it fixed. here is what i did.

1. i removed the EGR valve and put the block off plate on. i really did this not expecting much if anything at all. well i believe i did.

2 here is how i set my timing. first i set it (as everyone was saying)with 14* initial. well i did tghis with the advance still hooked to manifold vacuum. i drove it for a tank of gas and the gas milage went to about 15mpg fromabout 12-13 with a BUTT LOAD of spark knock (valve clatter). then i figured i dont have spark knock at wide open throttle so i went to TDC with the vacuum advance disconnected. with it connected i believe it is about 16-17* initial. man this thing runs great and i believe the milage went up some more, will have to update on it. BTW still no spark knock at wide open throttle. BTW i figured i would see what kind of tire spin i had and the thing spun tires all the way through second ( no crap) and i had the TV cable adjusted to loose , it switched to second way to soon, but kept spinning. i have not had that type of oprotunity again yet but i will try the tire spin again. it still feels like the bed is twisting when it changes to second gear though but thats why i spent the 1300.00 bucks on the tranny for.

OH yea and the drivability on the freeway, i have to continue to look down at the speedo to make sure i aint getting to carried away with the speed.

just thought yall would like to know

[MylilBowTie]

Sounds good. What all did you have done to the transmission?

Cant wait till I get mine back from the transmission shop, so I can test n tune.

[swervin ervin]

Jeff,

timing is real strange indeed. I'm can't remember exactly what it is you have. Timing can make or break your power/mileage.

First, get you a Crane adjustable vacuum canister. It comes with springs for the mechanical advance. Next read this article on my site about how to install and adjust it.

If everything else is in the distributor is in good shape and not worn out, it will work wonders for you.

First, your initial needs to be set with the vacuum hose disconnected and plugged. If the mechanical advance is set up properly, you should be able to run 12-15 degrees initial on a 9.1 to 9.5 CR engine without any trouble. Trouble is stock vacuum advance canisters have way too much advance in them. Some with more than 20 degrees. You need to limit when it starts and how much vacuum advance you have. This is what the Crane kit will do.

I can't stress this enough. Advance springs and vacuum canister will work wonders for your truck. This I know for sure.

But, if you think what you have now is working for you, how am I to say it's wrong. I hope it works great.

Oh yeah, are you running manifold vacuum or ported?

[bigd65]

Mike , i know you have told me and told me, i think now i will listen this time. it runs good but right off idle the is a vibration on acceleration and deceleration, but ONLY RIGHT OFF CLOSING AND OPENING THROTTLE. the more i think about it, it is probably a timing problem. the milage is still god and it breaks the tires so easy but it is kinda irritating. also if i am cruising about 45 there is a shimmy. some one else has posted about this and i dont think the problem with mine is in the suspension or steering.

THIS THING IS REALLY GETING ON MY NERVES

ONE MORE QUESTION:

is this canister gonna limit the total vacuum. i hear that at wide open throttle the advance cannister plays no role in the timming. if i set my timming at 10* i have clatter at wide open throttle.how can i limit the total timing on it

[swervin ervin]

Yes, the canister limits total vacuum advance. It also helps control when the vacuum advance starts. I remember a while back you saying you hooked your vacuum up to ported. Do you still have it this way? Manifold vacuum is better IMO. This is a arguement which has been going on since it started.

At WOT, vacuum advance don't have anything to do with the total advance. This is controlled by the weights in the distributor. Stock HEI distributor have 20 degrees total mechanical advance. Then according to what is needed, you then set the initial to 12 to 16 degrees for a total of 32-36. SBC's run best in this range. I run a total of 35 degrees. My MSD distributor has 21 mechanical and I have 14 initial.

What is going on with your's is the vacuum in my opinion. This is what the Crane kit will fix. You install the new springs so the advance starts right off idle, in the 1000-1200 rpm range. You want it all in no later than 3500, 3000 or so is better. The kit comes with an assortment of springs. I used both blue springs in my old distributor. This starts the advance around 800-900 and is full in by 3200. My MSD distributor won't let you install a Crane advance canister because of the ways it's made. I would have one if it would. But so far, the MSD is working great. They have a good canister to begin with. It also comes with an assortment of springs and bushings to change the advance to suit.

With the vacuum advance controlled this will work great. Don't worry, if everything else is in good shape, we'll get it dialed in for you.

Mike