ok...still nothing.....

[MI95Cobra]

well i found a few messed up spark plug wires...so i bought s new set and still nothin...it turns over faster but still backfires....i'm running out of ideas...should i try and reset the dizzy again??? also i think i'm going to just leave it alone...buy the new heads i want, put them on and have a mechanic fix the problem.... ...i also bought an obd1 diagnostic scanner...think that could tell me the problem???
jimmy

 

[Stanger007]

Sounds like Grady's advice he gave you earlier might be it - if you are backfiring either a valve is hanging open or your distributor is off?

I didn't read all the other threads but did you try a compression or leak down test?

Wes

 

[red95gtconvert]

This is definately the hard way to do it but you've already had alot of problems anyway so... Why not restab the dizzy one tooth clockwise and try starting it, if doen't start just keep repeating the process until it does. It may take quite a few trys but you will find the right spot eventually. I've done this before and had the car running within 15 minutes. Good luck.


On a side note I will be in OKC thursday and can possibly come by and take a look at it with you if you want.

 

[GTJake]

Eliminate the fact that it could be the dizzy first. I don't know how you've been doing it before, but here's what I do.

Take out the #1 plug put your finger over the hole and crank it over slowly until you see the balancer coming up on 0* BTDC. Then when you're close, take a breaker bar and crank the motor over until it's at exactly 0* BTDC. Stab the dizzy in so it's pointing directly at the #1 terminal. Put the hold down clamp on the dizzy lightly just so it doesn't move too much. Pull the spout and have a buddy start the car and you stand next to the motor and get ready to twist the dizzy clockwise to advance the timing a hair.

Jake

 

[MI95Cobra]

i thought about pulling the distributor and checking the gear on the bottom and restabbing the dizzy...i'll let you know how it turns out....

 

[final5-0]

well i found a few messed up spark plug wires...so i bought s new set and still nothin...it turns over faster but still backfires....i'm running out of ideas...should i try and reset the dizzy again??? also i think i'm going to just leave it alone...buy the new heads i want, put them on and have a mechanic fix the problem.... ...i also bought an obd1 diagnostic scanner...think that could tell me the problem???
jimmy

Jimmy

I've given some thought about your ordeal since you installed the heads that have been cut an unknown amount.

Here are the basic things that need to be checked with the valve train

1) Rocker tip travel distance over the tip of the valve

2) Position of #1 to see if it is centered over the tip of the valve

3) Spring coil bind

4) Clearance between top of retainer and bottom of rocker

5) Correct lifter pre load

You can get all specifics of 1-5 on the big cam folks sites btw

While all 5 things need to be correct for proper reliable operation ......
I got a simple test you might wanna do to give you an idea of
what is going on with things.

Since you got cut heads ... it is #5 that I suspect is causing you the
biggest problem.

You said in another thread you had no compression. I suspect your
pre load is too deep in the lifter and holding the valves off their
seats.

Before you buy new heads or spend a lot of money for a mechanic ......
Consider this as a test to check things out.

I got my mic out and checked several of the thinnest washers I had
laying around the garage. I found the range to be 40 to 50 thou
which is close enough for what we wanna do.

Instead of buying a shim kit you could just place a washer on each
side of the ped bolt for a temporary shim to preform our little test.

If you find you then got compression ........
the pr's could be too long

btw ... this has nothing to do with dizzy timing and is valid even
if the dizzy is not installed in the motor.

One last thing here is this ............
This test is only to check things ... don't start the motor

Grady