Any other ideas!!!! Thanks
Could it be the distributor
Thread Starter
Drifting
Joined: Sep 2005
Posts: 1,441
Likes: 1
From: Woodway TX
Could it be the distributor
Hey guys, on a recent rebuild on my 89 TPI all went pretty good with just a few problems of course. The last prob. that I am running up against is pre ignition detination. When I set the timing at 6 BTDC it is real bad, I backed it back to 4 BTDC it is not as bad but it is still there plus a loss in power that you can feel. I have prem. gas in it + I added some octain booster just to see if it would help, nope. My question is could it be that the distributor is bad? If so what should I expext to pay for a used one.
As always, thanks Don F
As always, thanks Don F
Instructor
Joined: Jul 2005
Posts: 133
Likes: 0
From: hartwell ga
Hey Dave
There is a shop in Waco called Nitro Dave's on the main street (it is where all of the used car lots are, not Valley Mills Dr.) The head mechanic there is a trained GM mechanic. They do a lot of work on F-body cars and some rice. They might could help. THey guys there are honest and friendly AND they know their stuff. Just an idea to get you rolling. I used to live off Chapel Road in Hewett.
Barry
Barry
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
What happens if you keep retarding it, or just time it by ear?
Are you sure the balancer is in good shape? These can spin off their mark by a few degrees.
Are you sure the balancer is in good shape? These can spin off their mark by a few degrees.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Did you set the dist in correctly and check spark plug wire routing?
#1 at TDC and balancer mark at 0*.
Had a problem with my 86 where dist was out of time, but I could set the base timing where I liked, on the balancer.
#1 at TDC and balancer mark at 0*.
Had a problem with my 86 where dist was out of time, but I could set the base timing where I liked, on the balancer.
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
1) What's the STATIC compression ratio ?
2) What's the CAM specs. ? OR... What's the Dynamic Compression Ration?
3) What's the quench ?
Got to know these or you're tuning with a blindfold on.
BTW, Did you disconnect the 'Brown' wire before setting the base timing?
Another BTW... those little bottles of 'Octane Booster' are snake oil.
There's NOT ENOUGH of ANTHING in those little bottles when mixed with 10~20 gallons of gasoline to make a knat's 'eye's worth of difference.
No, I DON"T CARE WHAT it sez on the bottle. Hey, wanna buy a bridge on the East side of New York?
2) What's the CAM specs. ? OR... What's the Dynamic Compression Ration?
3) What's the quench ?
Got to know these or you're tuning with a blindfold on.
BTW, Did you disconnect the 'Brown' wire before setting the base timing?
Another BTW... those little bottles of 'Octane Booster' are snake oil.
There's NOT ENOUGH of ANTHING in those little bottles when mixed with 10~20 gallons of gasoline to make a knat's 'eye's worth of difference.
No, I DON"T CARE WHAT it sez on the bottle. Hey, wanna buy a bridge on the East side of New York?
Last edited by VetNutJim; Mar 24, 2007 at 12:33 AM.
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Melting Slicks
Joined: Jun 2004
Posts: 2,328
Likes: 0
From: Central TX
we also pulled all plugs, replaced with new gapped ones, wrote with permanent marker on each wire, and rerouted
same problem
and yes,all timing has been done with the brown ignition wire pulled, as according to the GM manual
upon accelaration, you can hear and feel it detonating
it is basically a brand new stock motor (heads, cam, lifters, etc.... maybe slight higher compression forged pistons)
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
1) What's the STATIC compression ratio ?
2) What's the CAM specs. ? What's the Dynamic Compression Ratio?
3) What's the quench ?
THAT'S what you need to be endeavoring to find out.
'Somebody' has to know the answers to those basic questions.
If 'Nobody' knows.... well.... good luck with it....Oh, and CHANGE ENGINE BUILDERS.
2) What's the CAM specs. ? What's the Dynamic Compression Ratio?
3) What's the quench ?
THAT'S what you need to be endeavoring to find out.
'Somebody' has to know the answers to those basic questions.
If 'Nobody' knows.... well.... good luck with it....Oh, and CHANGE ENGINE BUILDERS.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Don, is the EGR system working correctly? When mine was failing it did the same thing as you described. Id love to see some pics or vids of the ol 89 in action. 
THe dist. was the original in the car, but shouldnt make it ping.
THe dist. was the original in the car, but shouldnt make it ping.
Last edited by cv67; Mar 27, 2007 at 01:46 PM.
Thread Starter
Drifting
Joined: Sep 2005
Posts: 1,441
Likes: 1
From: Woodway TX
Hey Ron, I am in the process of checking the EGR, EST, & ESC. It will take a little time though, every time I get my head in to it I have to do something w/ work, #@*+ CUSTOMERS!! Oh well, besides this problem the 89 is performing great. When it is cold no problem when the engine gets warm it runs with the pre-detonation. There was a wire broke loose in the distirbutor that I repaired before though. DonF
Last edited by DonF; Mar 28, 2007 at 07:54 AM. Reason: Finished