Tuning nite-mare...

[Freddie's Buick]

I threw in the towel. Waved the white flag. Hasta la vista babe. It'll have to wait for some other ocasion. And it's all because I have other jobs to start on.

I retro-ed my Buick to the 1979 old school version. Disconnected the ECM/EST and went with a vacuum controled HEI distributor and turbo style Q-jet. I also customized and modded two HEI vacuum distributors with new MSD springs weights and adjustable canister.

All this and could'nt get it right. It was a wierd timing issue. Heck I even got 5-lbs boost, (I have'nt seen it ever get to boost at all).

She would keep a steady idle and do several laps on the highway but when deceleration came she would lose all vacuum and die. I spent the better half of these last four weeks trying to figure it out but could'nt.

I suspected the carb but I swapped it out to the electronic one and it did the same thing. I then thought it may be the distributor so I swapped it out too and no change.

Frustrated I went back to the ECM/EST system. Runs like she used too. No vacuum loss or dying. I'm stumped.

Is there anyone out there that can provide me with a pic of their distributor indicating were you have plug #1 in the firing order? ('78's-80' only).

Because of my brackets I can only drop in the distributor a certain way and I had to relocate #1. This really shoud'nt be a problem. It's a smooth idle, quick start-up and no back-firing so I know It's not the firing order. I must of removed it and dropped it in at least 10-12 times and no matter what it still did the same thing. I've timed it from 8-15 BTDC. No differance.

Oh well, this experiment is inconclusive. That sucks!!!

 

[mat231v6]

what i did was have a guy modify the distributor so you dont need the vac advance. he some how did this by curving the distributor. i dont know how he did it but it only costed me like $65. it works great i just dont know how he did this so dont ask. i am still wondering even now.

 

[charlief1]

I'll try to post something for you tomorow Freddie. I'm just about to go to bed and havent got a pic handy. Hope you have a good night.

 

[Freddie's Buick]

.... i just dont know how he did this so dont ask.....

Lol...:biggrin: I was asking, (hate being stumped). Interesting idea though.
I do know this: The 1981 EST is a real turd. What a big differance in performance. The EST literally restricts power.

The only way to get that thing to move is a chip that is re-curved. No one is capable of doing this because the ECM was a one year run, (just like Charlie's bastard child waste-gate). I wonder if the 1982 is not too far off either?

Anyway, it is better to retro the electronics performance-wise. The only thing I left the computer to moniter was the TCC. Worked like a charm.(Just had to figure a way to shut off the check engine light). The after-market version of TCC control will blow a hole in your wallet for a $160.00.

I never ripped off the ECM though and probably never will. I can switch back and forth for as long as the computer still works. For now I'll just keep runnig it OEM. I will go back at a later date and see were I went wrong with my retro experiment.

 

[unboostedV6]

I don't remember much about the carb'd turbo thing and vacuum plumbing, but if you want to lock out the vacuum advance, unbolt the vacuum can and fab up a little plate to fit in its place which pins the pickup coil still. Be sure to index it as well. GB

 

[charlief1]

I threw in the towel. Waved the white flag. Hasta la vista babe. It'll have to wait for some other ocasion. And it's all because I have other jobs to start on.

I retro-ed my Buick to the 1979 old school version. Disconnected the ECM/EST and went with a vacuum controled HEI distributor and turbo style Q-jet. I also customized and modded two HEI vacuum distributors with new MSD springs weights and adjustable canister.

All this and could'nt get it right. It was a wierd timing issue. Heck I even got 5-lbs boost, (I have'nt seen it ever get to boost at all).

She would keep a steady idle and do several laps on the highway but when deceleration came she would lose all vacuum and die. I spent the better half of these last four weeks trying to figure it out but could'nt.

I suspected the carb but I swapped it out to the electronic one and it did the same thing. I then thought it may be the distributor so I swapped it out too and no change.

Frustrated I went back to the ECM/EST system. Runs like she used too. No vacuum loss or dying. I'm stumped.

Is there anyone out there that can provide me with a pic of their distributor indicating were you have plug #1 in the firing order? ('78's-80' only).

Because of my brackets I can only drop in the distributor a certain way and I had to relocate #1. This really shoud'nt be a problem. It's a smooth idle, quick start-up and no back-firing so I know It's not the firing order. I must of removed it and dropped it in at least 10-12 times and no matter what it still did the same thing. I've timed it from 8-15 BTDC. No differance.

Oh well, this experiment is inconclusive. That sucks!!!

Ok Freddie, I've slept and have a little more time on my hands now. Have you tried using the stock ecm distributor and set the timing for 18 degrees and locking it out for testing? This would help you determine if it's a distributor issue or something else. I think this is why Fred set his system up with the MSD box and adjustable timing unit. It allows you to manually adjust the timing of the engine while you're driving and the puter won't have any control over it.

As far as the #1 plug position it really doesn't matter on a non CCC system. You can put it where you want because the fire is just a stupid system.

 

[Freddie's Buick]

....Have you tried using the stock ecm distributor and set the timing for 18 degrees and locking it out for testing?

I did'nt have to lock it. The EST distributor has a default timing curve good enough to run without computer control. Yes I did try this. Car would not die. Ran fine. But this is not what I want to do.

....This would help you determine if it's a distributor issue or something else. I think this is why Fred set his system up with the MSD box and adjustable timing unit. It allows you to manually adjust the timing of the engine while you're driving and the puter won't have any control over it.

Charlie, going retro is going without the computer. I do have an MSD box with separate timing control. I had to disconnect the MSD system because it stumbled and was worst with the box. Tried with 4-pin modulator, 5-pin modulator, magnetic trigger and the stumble continued. So in order to rule out MSD I disconnected it. Went old school stye, strickly OEM. It did'nt stumble but on deceleration vacuum was low and the car died.

....As far as the #1 plug position it really doesn't matter on a non CCC system. You can put it where you want because the fire is just a stupid system.

That's what I've always thought, but I've experianced on several ocasions in the past that for some reason some Buicks run better close to it's stock firing position. That never happened to me with Chevies.

 

[charlief1]

Are you using a PEVR valve Freddie?

 

[Freddie's Buick]

Heard a lot about them but never seen one. All the postings that mention it no one seems to know how they actually work.

All I did was put a check valve on mine.

 

[b4black]

I do know this: The 1981 EST is a real turd. What a big differance in performance. The EST literally restricts power.

Is you knock sensor/module working right? On my '83, I can tap on the intake manifold with a hammer and hear the idle (timing) change. I wonder if you ESC is retarding timing all the time. Can you see the timing retard with a scan tool on a 1981?

If assume your intial timing is about 15 BTDC. Can you check it higher RPM's with a dial back timing light?




On my '82, I'm thinking of using a '83 ECM and wiring harness that I have. This would let me use the '83/'87 piezo style knock sensor. I don't have a lot of experiance with the earlier 81/82 accelerometer. I presume they had a good reason to change it.

 

[Freddie's Buick]

Hi Rich,

Good hearing from you again. I don't have an ESC or knock sensor installed. I have an ESC but without a knock sensor it would be irelevant to install, (those knock sensors are way too expensive for an experiment for now).

If I'd succeeded getting it tuned I probably would of made the effort to find one.

I do have a dial back timing light and all the checks I did showed that everything was in order. It was deceleration from a good run that baffled me. I really had no way of knowing if the timing dropped since I was driving it. But it is my suspicion that it had to be timing/distributer related.

Both non-EST distributers I installed did the same exact thing. I ruled out the carburetor since installing the EST distributer eliminated the problem.

I'll go back to this when I finish doing new valve stem seal cuts, new exhaust valves, modified timing chain cover mods and volume checking my compression with a burrete.

I'm also replacing my HT-969 lifters with my freshley rebuilt Kenne-Bell Hi-Rev lifters. (I had removed them after only 2-years use when one started ticking back in 2002).

I need to put my Sunday driver back to daily driver status, (this ought to breath some new life into this turbo-beast).

 

[mikemcvaney]

I know where number on is on the cap will look at my distributor monday and tell you its a 1979. Mike

 

[mikemcvaney]

Numberone

Its on the left of the wire hook ups on the cap.

 

[Freddie's Buick]

Thanks Mike.

That's exactly were I lined it up to. Funny how the EST distributors are located to the right of the wire hook-ups.

I guess I'll keep looking but I think I know what it was.....I will only be able to confirm this way later on down the year if I'm lucky and I can find the time to re-start this experiment.

 

[Freddie's Buick]

Problem Solved!

It was a stripped stud and opened gasket on the compressor elbow, along with a bad wastegate hose. The stud allowed air to get into the intake through the unsealed gasket. I found it accidently by spilling water on my intake while tuning the engine.

The water got sucked in and the engine choked with gas and water. Almost ruined my plugs and my head job. After I re-threaded the stud and sealed the elbow up again I had to pour denatured alcohol to dry the plugs and any water inside as the engine sputtered and fought to stay on.

This trick always works for me and eventually in a few minutes the engine began to purr. The hose was broken from the inside so it was hard to see, but I easily found it becase the elbow was finally sealed and the hose leak can be heard.

Although she's back to how I had it set up before, all the MSD stuff is up and running like new.

With this in mind some time in the future I will try this again and store away the EST/HEI distributor for the vacumm type HEI and the non-electronic carburetor. I really think performance-wise it's the ticket!

 

[charlief1]

Glad to hear it Freddie. Sounds like you're getting her squared away again.

 

[Freddie's Buick]

Well I finally went back to it and it works outstanding! No module...the MSD triggers it so no electronics in the distributor other than the coil. The Pontiac carb I built up for it works fantastically. No worries on the TCC issue either. A B&M kit for converter lock-up control will bypass computer control and work automatically. It uses a speed sensor on the trans for automatic lock-up.

One can manually adjust the sweet spot on the dash.

 

[dr_frankenstein]

good to see its alive brother!

 

[Freddie's Buick]

Couple of things I ran into with this are important hopefully to anyone that needs info. For one, I read somewere on the www that it does'nt matter were one drops no. 1 as long as the engine is on TDC. WRONG! For some reason it does matter on the V6 if you're using a CD unit like the MSD. It will start and actually run but the timing would be way off the timing tab by 20-60 degrees depending on were one drops no.1. It will not run well at all.

Also, I was dumb enough to think I could use a Chevy V6 HEI. IT WILL NOT WORK! Same as above, it will start but run erratically. The difference is in the center shaft that holds the rotor. It's forged in a different position than that of a Buick. No mater if you drop it correctly on number one it will still be off.

I ran into these two issues but there is one more thing one has to be careful with. When setting up TDC on a Buick V6 just because you line up the timing marks on the pulley, and the distributor rotor faces no. 1 it doesn't mean it's on TDC. To be absolutely sure remove No. 1 spark plug and see if it's actually TDC. It can also be on BDC, (in which case just turn the crank one more revolution and line up the marks again).

This is unique to the V6 engine. The V8 obviously will always line up. That's were the confusion is.

 

[ek02]

The engine is not on BDC, but actually at TDC on the exhaust stroke when the distributor is 180 degrees out. When the mark on the damper is on the "0" timing mark on the front cover, the #1 piston will always be on TDC. It could be on the compression or exhaust stroke depending on the position of the cam. Remember there are 4 strokes in 2 crank revolutions. Intake, compression, power, and exhaust. A V8 can be timed 180 degrees out just like a V6. You can drop a distributor in, in any direction, as long as the rotor lines up with #1 in the cap on the compression stroke. The problem is, the vacuum advance needs to be in the correct position to fit, so it has to be timed so the rotor lines up with #1 in the cap on TDC of the compression stroke. Then, you need enough room to move the distributor to get the timing right. It's easy to be a tooth off and not be able to get the timing set because the distributor can't be turned enough in the direction it needs to go and still have the vacuum advance can be in the right place. Backing up or going forward a tooth can be hard to get right. Your engine looks great. Hope it runs good.