Just rebuilt my 350 for my 91 z28. I got eveything done and now the engine is back in, ac/emmision delete, i got a bigger cam, a comp cam computer controlled #305 cam, .276 .290. Now my dad and i have been trying to get the timing right and the thing to idle for about a month now. We get it to fire fine, some times it does a quick fire then quit, then another turn of the key w/o moving the distributor and it cranks does a slow fire the runs for 2 seconds then quits. Then we move the distributor here and there and it idles, we set it, sounds great, tightin the distributor and try to start it and it does the quick fire and dies right away thing and we never get it to stay constant. We try it with the est in then out. We have no idea, any suggestions would be awesome!!!!!!!

 

are you still using the ECM/EST controled distributor? are you setting timing with ST unplugged, or plugged in? what did you remove, and why?

 

Oh, yeah. ede is all over this one. If you removed/altered some of the wiring as part of the "ac/emmision delete", and the ECM is not getting reference pulses from the distributor, the fuel pump won't run more than a couple seconds unless oil pressure builds quickly. If you altered that wiring, the oil pressure may not even make a difference, and you might be running briefly on only the initial fuel pump prime.

So...?

 

I didn't remove any wiring, i just dont have the wiring plugged into what went to the ac and emmisions. Everything else is the same, is does run, and will run good when we get the distributor set after awhile, but then it just never restarts or stays running after that, so i cant drive it anywhere because it never runs the same from firing to firing. I had the chip custom burned by tpichips.com with all my specs and deletes and such.....

 

in terms of the est, we tried to get it to run without it plugged in and now with and it is the same.

 

You do know that you have to unplug the EST, set your base timing, and then you can plug it back in, right? You dont set the timing with the EST connected ever, right?

K.I.S.S.

 

Check your wiring going to the Distributor and E.C.M. and see if something is amiss. If not, plug the emissions stuff back in one at a time and try to start the car and get it running right to see if maybe you unplugged something that shouldn't have been unplugged.

 

Were the head, and or the block surfaces machined?
Are you using the intake, and distributor from before the rebuild?

 

Yes im using the same distributor and stock intake but ported and polished. No machining was done excpet the crank was ground down and cylinders, usual stuff.

 

Ok I just set the timing with the est disconnected. Set it too about 8*, sounded good ran good. Shut it down, disconnected the batt. plugged the est back in, waited 5 mins. Started it, took a little tweeking ran, but when I put it into gear it dropped so far down in rpm it kills right away. So what base timing should I set it too first off, any ideas. and also what do you think the killing could be from ??????

 

Now check to see if the base timing is still set to 8°, if not (I'm sure you locked it down) either the distributor is bad (mechanically,) or it's bottoming out enough to keep it from locking down securely.
If the base timing has changed, reset it, lock it down, and leave the engine running, and the timing light connected, scribe a fine line on the base of distributor, continue the line onto the intake. Aim the light at the pointer, rev, and hold the engine at a steady rpm above 1K. If the timing jumps around then the distributor is bad, if the timing doesn't jump around, but slowly advances, the distributor is bottoming out. Look to see if the line you scribed is still aligned.
If not you'll need to insert spacers between the distributor, and the intake. If it's still aligned, I've wasted your time, and now I'm just as frustrated as you are.
BTW, what do you mean by a little tweaking?
FYI
Part stores, at least none where I live carry nylon distributor spacers - Performance stores do.

 

Set your base timing at 0 and see what happens. I'm also curious about the tweaking you had to do to get it running.

 

When it fires and runs, we rev it and rev it, everything is fine, then we put it into drive and it takes a second then drops rpm so much that is chugs and sputters then eventually dies. The book says 6*, but does it change with a fairly big comp cam, .276 .290 114 lobe?

 

I can't imagine it being that bad with a 114 lobe seperation angle. Are you sure you don't have a vacuum leak? Maybe the timing is retarded to far. Try bumping it up a little and see what happens.

 

Not to bust in on your thread but when setting the timing and
you have to move the dampener, there are three smaller screws
and one bigger one in the center. I need to put a breaker bar
on that center bolt head and turn it to get the groove on the
dampener to 0* right?
Question: If I move the dampener like I mentioned above, won't
that move the piston from tdc????????????????/
Right now the groove is on about 10 or 12*.
Also, do I need to take the serpentine belt off to move the
dampener?

 

If you move to 0° that is TDC, but it may not be the #1 piston TDC on the compression stroke.
You don't set the timimg by moving the crank manually, this is done to get the engine to start so you canset the timing to 10 - 12°.
You don't need to remove the belt.

 

So bump the engine until the groove is either close to or at 0*
and then manually put the groove on 0* (if it is not already
there), and move the rotor to the #1 firing position.
I am by the way trying to get the car to start. Right now it
doesn't and it is probably because when I replaced the dizzy
I didn't mark it correctly.
So it doesn't have to be on the compression stroke to start
the engine huh? I thought that it did.
Thanks!!!!

 

The spark needs to happen on the compression stroke for the engine to start.
To fire up the engine to set the timing:
1.) Pull all the spark plugs, or as many as you can get to.
2.) Remove the dizzy cap, manually turn the crank until the rotor is pointing at the #1 on the dizzy cap. Where the damper groove is doesn't matter at this point.

3.) Pull the dizzy out slowly, watch the rotor as you pull it out, it will turn a little counterclockwise, this is the postion the rotor needs to be in when you drop it back in.
4.) Stuff a rag in the #1 sparkplug hole, or use a screw in compression tester.
5.) Manually rotate the crank until the rag pops out, or the compression tester begins to indicate pressure. The groove should before the pointer, continuw turning until you're at 0°
6.) Put the dizzy in with the rotor in the last position it was at when you pulled it out, install the clamp.
7.) Put the cap on, aligning the #1 spark plug wire post with the rotor, and lock the clamp down.
8.) Put the plugs back in, connect everything up, and fire it up.
Don't forget to disconnect the EST before setting the timing, and reconnecting it afterwards.

 

i am having similar issues with timing and i need to do what you just described, i understand everything in your steps except the part that goes:

"The groove should before the pointer, continuw turning until you're at 0°"

what is the groove and pointer?

and i assume that when you say continue turning until your at 0* means keep turning the engine until it reaches TDC in Cylinder#1? does the groove and pointer tell you when its at TDC? whats the groove!? lol

 

do you have a manual or auto? If it's manual, are you sure the clutch is disengaged? Just a thought...

 

I guess turning the crankshaft can be considered "turning the engne," but remember your doing it manually not with the starter.
The groove is the piston TDC timing mark cut into the damper, and the pointer is the o° location on the timing tab on the timing chain cover. Just continuing with what Dark Scorpion used, "groove."
The engine turns clockwise (if you're facing the front of the engine) compression will build and pop the rag out before the timing mark reaches TDC (o°.)

 

We retard and advance the timing so much to try to hit it right that our hands bleed. I sorta new at this but my dad isnt really. How important is it hen u set the base timing, is that the key. So should I set it to 0* and then plug the est back in then set the disributor to get it to run good. I think the base timing is at 8* right now. We set the disributor and it ran fine, rpm at idle was up around 1500, got to drive it down the alley. Then slowly it started to just chug when it ran and now it doesn't start all together!!!!! Do you think my distributor is bad to make it go out of wack like that. Or could it be something else. Sorry guys I want to drive my car so bad it hurts.

 

OK, this is what happened we just went out and farted around. With the EST OUT, we were trying to set base timing and someone said try 0*, so we try to get it to fire, takes a while to then when we hit the right spot on the distributor it fires, check the timing it is almost up and down like at 18*, and it is alternating and moving from 12* to 16* then 18* mostly 18*. We try to bring it down to 8 and it really slows up and then 4* and it cant keep up and kills. We cant even get to 0*. It sounds really good at like 18*, So my dad thought maybe it is off a tooth because its nice at 16 or 18* and kills at 6*, but it is really harsh and doesn't fire so the tooth must be right. This is F*%k#ng pissing me off. Any ideas.
Do u think it has to do with open headers or not...no back pressure?

 

It should run good at 0°.
When the #1 piston is at it's exhaust TDC the timing mark on the dampner/balancer should should be at 0°, and the alignment marks on the timing gears should be facng each other, when both the cam gear, and the crankshaft mark are at the 12 O'clock position the #1 piston will be at it's compression TDC again, the dampner will align with O°.
Assuming the cam/crank gears are properly aligned:
If you locked the distributor down, and held the rpm steady (with the EST disconnected,) and the timing mark was alternating it's a symptom of a bad distributor.
I think you should verify cam crankshaft gear aligment, if you don't agree with the bad dizzy assumption.

 

I hate to make more work for you, but I really think you should check your timing chain and gears. You might be suffering from a stretched timing chain. The pointer moving back and forth is usually a sign that the Distributor bushing is worn out, but if the chain is stretched like I think it is, then changing the Distributor alone won't fix the problem. My buddy Joey had the same thing happen on his Mustang. Check the timing chain and gears to see if they're stretched first, so that you can see if you need to replace them. I know you must be getting frustrated by now, who wouldn't be, but this is a necessary step. If you have to change the gears and chain, get a new Distributor, it doesn't have to be anything special, and replace the chain, gears and Distributor. After you've done that, your problem should be history. Then all you have to do is set your timing and you'll be off and cruising in no time.

 

Thats one thing I made sure of was that they are aligned because I don't want to have to do this. I aligned the two dots on the cam and crank when I installed it, I don't know. Im about to take it to a shop and say make it work. Any info on the open headers, that doesn't matter right. It was really fluttery at 16* but at 8* or closer it didn't flutter hardly at all, timing mark stayed put.

 

Is the chain and gears you installed brand new?

 

Yes they were top of the line new and expensive.

 

Then I have to go with the worn Distributor bushing. Get another high quality Distributor and stab that in there. There's really no sense in fixing that worn bushing unless you've already rebuilt a good portion of the Distributor with high quality name brand parts. M.S.D. and Accel would be excellent choices. I know Mallory exists, but I've never used any of their parts. My brother in law has, and he's enjoyed them. Not trying to dis anybody's favorite, just talking from my own experience.

 

Ok we got it to run, we figured out we were in the wrong tooth before, so now when we get it to fire and run it sounds better, runs fine, we can take it up to 4 grand and it sounds really racy. Set the distributor and shut it down then re fire it, it fires up fine, shut it down, fire it again, starts fine. Sweet, maybe we got it. So we close up for the night and try it the next day and it doesn't start for the life of it without messing with the distributor again.... what do you think that is...?

 

I still think you need to check that bushing. If your timing chain and gears are new and the timing pointer was still fluctuating, then the problem has to lie in the Distributor. If you know somebody with one of the old Distributor testing rigs, then you can take it there and have them check it out. A new el cheapo Distributor will only run you like 50-100 bucks. I think you'll find that it fixes the problem.

 

Sounds like the distributor is toast.... I love excuses to buy upgraded parts, dont you?

 

I love new parts.

 

So a bad dizzy will cause the car to not re fire after a while when we had it running perfect an hour or so ago.

 

a bad dizzy can do a host of symptoms. Some being very very hard to diagnose... espescially when you want it to be anything BUT the dizzy lol....

If you want, you can get a junkard one for fairly cheap... but me, I'd get one from MSD, and I'd be able to justify it by pricing a new one from the dealer... calling the dealer to get brand new OEM replacement part quotes, and then looking at the much better aftermarket ones for about the same, and sometimes a little cheaper than OEM.. it makes me feel like I got a good deal... espescially if I can find that aftermarket part on eBay

 

oh, and you should check other dizzy parts firstly by the picture below. I realize that it is for a V6 dizzy, but the same principles apply to a V8's, they just arent in the same place sometimes.

 

ok, well what dizzy should I get, I don't want to spend a terrible amount of money. If you guys could give me a part # or anything I have gotten alot of the wrong parts in the past, and on summit racing theres different types, magnetic, electronic, male, female hei, so what would work most diffinatly for my setup and application. Any suggestions....

 

One from the junkyard should work well

 

a rebuild should only run you somewhere in the low $1xx range... I just dropped one in my car last weekend (found everythign inside mine was toast)

 

I have a quick question before I attempt this procedure again for the 10th time.. so when you refer to #1 cyl TDC aligning with the 0* mark on the tab, does this happen every 1 revolution of the balancer? or does it essentially need to rotate eight times for each of the 8 cyl to reach TDC?? the reason I ask is cuz I was doing the procedure and the rag didn't pop out but I lined it up to 0* and dropped the dizzy in with rotor pointing 4:30 ... car idles but bad miss during accerlation..

 

If I were to go with a msd what kind should i get exactly. Id kind of like to go with new.

 

The miss could be related to the Distributor problem, as well as a host of other things. Fix the Distributor first, and if the problem persists, post back and we'll be able to help you out from there. The other possibilities are mostly pretty minor and will only cost some time to fix. The Distributor needs to be removed from the trouble-shooting process first. One last thing; relax. You're doing fine and you have the right idea about the balancer. It won't require 8 full rotations for each cylinder to reach T.D.C.

 

ok well I was at it again got a new lifetime warranty pos dizzy from autozone put it in with the balancer lined to 0 and the rotor pointing to #1 as best as possible. hooked everything up and got it started.. ran good for like 3 min literally then went back to same prob with it missing at 6 deg BTDC. so I really don't know at this point I mean my fuel PSI goes up to 31 then drops to 0 then up to 31 while cranking and running. so maybe it's fuel not spark?? but I have this strange feeling I messed the alignment of the dizzy up somehow and it could be my problem. so just to reconfirm ANYTIME the balancer mark is at 0 deg on the tab it means #1 TDC?? once every revolution? thought somewhere on here it said every other (so 2 revolutions). also is the protruding metal tab or the square plastic side of the rotor supposed to point to #1 spark plug. I know it seems obvious but one time it didn't fire with metal side facing #1, flipped it and fired but ran crappy. I did turn the oil pump a little to make it line up with #1 more but I think I made it worse. I will re-read all the info here and try again tomorrow.

 

The balancer makes two full revolutions between #1TDC, IIRC the other is #8 exhaust.

If it ran fine for 3 minutes then it is not timing related.


What is your fuel pressure at while it is running? What is it at idle? At WOT? What is it when you shut the car off? How about 10 minutes after you shut the car off? How about when you turn the key to the ON position?


This is a TPI motor, right?

 

Sellmanb is all over this one. I might chime in if needed, but it seems like he's on the right track. One question though, is the timing mark staying solid now, or is it still moving back and forth?

 

OK. I am just about ready to try some of this but I have one
question. How do I manually turn the crank to get the groove
to 0*. I had a socket and a wrench on the center bolt on the
balancer and it didn't look like anything moved???????
Do I need to get a pry bar and does the cap need to be off
the dizzy???????????????

 

Use a socket and a breaker bar. It should work.

 

Taking the cap of the Dizzy would help, turn the crank until the rotor is just before the #1 wire tower, you should see the balancer mark close to the Zero mark.

 

i got a question here.. while idling and looking at the timing mark it will stay steady at 6 deg BTDC. then I hold the accelerator at about 2000 rpm and the line jumps to like 20 deg btdc. is this normal or is it supposed to stay where you set it (6 deg BTDC) @ 600RPM and 2000 RPM?? i'm thinking my balancer might be slipping, some of the rubber on it is off. before i replaced dizzy it would actually go a few deg the other way, so down to like 4 when revving.. oh btw I have EST bypassed.

 

you have some type of timing advance, either from the ECU or a vacuum advance, that is why it jumps.