# Won’t start after trying to check time



## MattH (Nov 1, 2020)

I recently installed a new accelerator pump & N/S. Car would run strong but not pull hard. I wanted to start with timing so followed Lars instructions but now car won’t even start. Removed rotor/cap and removed 1 spring weight, then install rotor/cap and start the car. I don’t have a dwell meter but would try turning allen until misfire then back 1/2 turn. Carb had a small flame so blew it out and tried again. It backfired extremely loud so I want to reach out before I proceed any further. What am I doing wrong and why won’t it start now?


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## Lemans guy (Oct 14, 2014)

You can rotate the engine in neutral with a breaker bar. Make sure key is off parking brakes on, chock wheel. Just get the points to sit on top of one of the distributor cam lobes.

then with a feeler gauge set the gap at .016. That will get it start, but a dwell meter is much easier.


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## MattH (Nov 1, 2020)

Thanks, I pulled #1 plug and brought up on compression stroke but now the stationary mark is about an inch away from the harmonic scribe. The 15/16” crank bolt is a insane to get to with the fan shroud in place.


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## armyadarkness (Dec 7, 2020)

Have you tried from underneath?


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## MattH (Nov 1, 2020)

armyadarkness said:


> Have you tried from underneath?


Yes that’s how I am doing it how. Maybe someone put the wrong fan shroud on. I’m following Lars timing instructions. In the distributor I removed 1 spring and 1 weight. This morning I was talking to guy about my issue and maybe leaving both weights in and only removing 1 spring is what my issue is.


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## armyadarkness (Dec 7, 2020)

Im very familiar with Lars and his papers... You're not supposed to remove a weight!


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## armyadarkness (Dec 7, 2020)

And if you are, then Ive been doing it wrong for a long time.


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## armyadarkness (Dec 7, 2020)

Without a weight on youll never get centrifugal advance. You want one spring off so that you get full advance early on in the revs... set your dizzy at 34 degrees to start. Then record the base time.


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## MattH (Nov 1, 2020)

armyadarkness said:


> Without a weight on youll never get centrifugal advance. You want one spring off so that you get full advance early on in the revs... set your dizzy at 34 degrees to start. Then record the base time.


I’ve always been a hard learner.. hopefully I didn’t tear anything up cranking it like that. I bet she will start now.


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## armyadarkness (Dec 7, 2020)

This is why police and fire have book and practical. It's impossible to put your knowledge to work, or fully understand it for that matter, until you have a practical application.

Learning geometry in school is a tedious and ridiculous task, but when you need to square your deck up, it all makes sense!

Cranking the engine with a fan is a pain, shroud is x10


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## MattH (Nov 1, 2020)

Q


armyadarkness said:


> This is why police and fire have book and practical. It's impossible to put your knowledge to work, or fully understand it for that matter, until you have a practical application.
> 
> Learning geometry in school is a tedious and ridiculous task, but when you need to square your deck up, it all makes sense!
> 
> Cranking the engine with a fan is a pain, shroud is x10


Haha, you ain’t lyin’. At least I know I’m doing something right. I cannot find a dwell meter anywhere… can anyone tell me how to set dwell angle with a multi meter?


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## RMTZ67 (Mar 12, 2011)

MattH said:


> Q
> 
> Haha, you ain’t lyin’. At least I know I’m doing something right. I cannot find a dwell meter anywhere… can anyone tell me how to set dwell angle with a multi meter?


Tons of dwell meters on ebay. Still use the one I had from my younger days.


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## geeteeohguy (Feb 2, 2008)

1. You need to re-install the missing weight.
2. You need to get a dwell meter.


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## MattH (Nov 1, 2020)

geeteeohguy said:


> 1. You need to re-install the missing weight.
> 2. You need to get a dwell meter.


I reinstalled the weight, brought motor to TDC, haven’t touched points yet (no dwell meter), lined up timing marks, rotor cap #1 plug facing button and she fired right up! Thanks a lot guys, now just need to dial in the timing and carb. How do I verify the 36-degrees of timing is coming in before hook back up the vacuum line?

Oh and get a new muffler after that backfire from yesterday.


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## LATECH (Jul 18, 2018)

MattH said:


> Yes that’s how I am doing it how. Maybe someone put the wrong fan shroud on. I’m following Lars timing instructions. In the distributor I removed 1 spring and 1 weight. This morning I was talking to guy about my issue and maybe leaving both weights in and only removing 1 spring is what my issue is.


That wont make a darn when it comes to starting.You must have a wire crossed or wires on wrong or dizzy in wrong. Springs and weights wont make it not start


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## PontiacJim (Dec 29, 2012)

MattH said:


> I reinstalled the weight, brought motor to TDC, haven’t touched points yet (no dwell meter), lined up timing marks, rotor cap #1 plug facing button and she fired right up! Thanks a lot guys, now just need to dial in the timing and carb. How do I verify the 36-degrees of timing is coming in before hook back up the vacuum line?
> 
> Oh and get a new muffler after that backfire from yesterday.


You can either put a sticky timing tape on your balancer or purchase a "dial-back" timing light. 36 degrees may be a bit much, so listen for that horrible engine "pinging" death rattle and if you hear it, you have too much total advance, your timing curve is coming in too fast, or you need high octane gas - or all of the above. Let the pinging go on for too long, and you can wipe out rod bearings, crack pistons lands, break rings, grenade the engine - and you just won't know which choice your engine goes with until it happens and then its all over but the crying.


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## MattH (Nov 1, 2020)

PontiacJim said:


> You can either put a sticky timing tape on your balancer or purchase a "dial-back" timing light. 36 degrees may be a bit much, so listen for that horrible engine "pinging" death rattle and if you hear it, you have too much total advance, your timing curve is coming in too fast, or you need high octane gas - or all of the above. Let the pinging go on for too long, and you can wipe out rod bearings, crack pistons lands, break rings, grenade the engine - and you just won't know which choice your engine goes with until it happens and then its all over but the crying.


Hard to tell with that muffler blown out. It seems to be real smooth and responsive 1k-3k, then starts chopping out. I found a dwell meter I’m going to pick up today and a new muffler. If 36* is too much where should I set it? Just leave it alone at the stock scribe?


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## PontiacJim (Dec 29, 2012)

MattH said:


> Hard to tell with that muffler blown out. It seems to be real smooth and responsive 1k-3k, then starts chopping out. I found a dwell meter I’m going to pick up today and a new muffler. If 36* is too much where should I set it? Just leave it alone at the stock scribe?



I like 34 degrees, but, you can start at 32, then bump up to 34, then 36 as long as you don't hear any pinging under wide-open-throttle load. You may not even feel a difference between 32 and 36, so why go 36 and take a chance of detonation you cannot hear, or detonation due to a 100 degree day, or poor quality gas you just got from the gas station. It also depends on things like compression ratio, octane used, camshaft specs, air/fuel ratio's, running engine temps, and even open/closed chamber heads. The 1967 and earlier closed chamber head seem to be OK with more timing. So it is not just as simple as setting the engine to 36 degrees and walking away. You also have vacuum advance which adds more advance at off-throttle/light throttle cruising. Too much can be a bad thing, but you certainly want it.

So don't just assume 36 as you can damage an engine. You may have to play with the Initial timing (at the Harmonic balancer), Timing curve (springs/weights), Total mechanical - no vacuum advance, the RPM this comes in at, and then your vacuum advance. Plenty of past postings on the forum covering this if you do a search using the above forum search engine.

If you still have the factory harmonic balancer, suggest you replace it with new - it could be way off due to the outer inertia ring slipping or it could even let go and do damage due to the rubber sandwich dry rotting after all these years.


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## geeteeohguy (Feb 2, 2008)

Everything Jim said in spades with one observation: while the 1967 and earlier closed chamber heads do run better with more timing (due to their design) they are unforgiving in a stock engine (flat top pistons) unless you run 100 octane gas. You will rattle your '67 and earlier Pontiac to death trying to run a full factory timing curve on 91 octane fuel. BTDT, and have seen it many, many times. My Pontiacs seem to like 34 mechanical all in. But keep in mind, it's close to 50 degrees with the vac advance connected at cruise speeds for economy. That can get you a little detonation if you are running too lean or too hot or both.


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## MattH (Nov 1, 2020)

geeteeohguy said:


> Everything Jim said in spades with one observation: while the 1967 and earlier closed chamber heads do run better with more timing (due to their design) they are unforgiving in a stock engine (flat top pistons) unless you run 100 octane gas. You will rattle your '67 and earlier Pontiac to death trying to run a full factory timing curve on 91 octane fuel. BTDT, and have seen it many, many times. My Pontiacs seem to like 34 mechanical all in. But keep in mind, it's close to 50 degrees with the vac advance connected at cruise speeds for economy. That can get you a little detonation if you are running too lean or too hot or both.


Guys I’m going to be honest, I don’t have a clue what y’all are talking about. I’m used to starting at TDC, point button at #1 wire and fire it up, get your light out and line the scribe up with the 0 or 10 degree mark. I found Lars timing information and decided to give it a shot. Now I wish I never did. Whats the harm in setting time just like I described above plus checking dwell before using the timing light?


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## PontiacJim (Dec 29, 2012)

geeteeohguy said:


> Everything Jim said in spades with one observation: while the 1967 and earlier closed chamber heads do run better with more timing (due to their design) they are unforgiving in a stock engine (flat top pistons) unless you run 100 octane gas. You will rattle your '67 and earlier Pontiac to death trying to run a full factory timing curve on 91 octane fuel. BTDT, and have seen it many, many times. My Pontiacs seem to like 34 mechanical all in. But keep in mind, it's close to 50 degrees with the vac advance connected at cruise speeds for economy. That can get you a little detonation if you are running too lean or too hot or both.



GTOGUY: "while the 1967 and earlier closed chamber heads do run better with more timing (due to their design) they are unforgiving in a stock engine (flat top pistons) unless you run 100 octane gas. You will rattle your '67 and earlier Pontiac to death trying to run a full factory timing curve on 91 octane fuel."

PJ: I would agree, but we have had several members tell me/us how they can run 93 octane with the 10.5 compression "067" heads and go with 34-36 degrees total. Not sure how they do it with iron heads, but the last post was from lars:

"Running 93 ( with 10% ethanol) and a lead substitute in my stock 65 389 w theoretically 10.75:1 no issue for typical weekend cruise work... about 36 deg total timing and a tad rich jetting."

"67 400 with 670's, Dougs headers, MSD dizzy, Edelbrock 800 cfm carb, 30 over, runs all day on 93, in 98 degree temps with 90% humidity."

"My 67, like yours except it had a points dizzy and a higher rear (maybe 3.08), would run well on 91 octane (no ethanol content), prefers the 93 however. On the hottest of summer days, the 91 might do a little dieseling when shut off at full operating temps (might)."

"670's were GTO-only heads in 1967. The flow pretty well, but they're closed chamber heads and usually need quite a bit of timing."

*lars *- "The engine was a 1976 Firebird 400 – I basically converted it into a 1967 335-horse (gross rating) GTO configuration with the “670” closed chamber, large-valve heads, which ended up producing an actual compression ratio of 10.08:1 with flat-top pistons and the stock deck height. The owner wanted a very mild cam to maintain engine vacuum and power brakes, so a mild hydraulic roller with specs similar to a Ram Air IV was used. No other trick parts – the engine was pretty much a 1967 GTO 400 with a mild roller in it. Total timing (stock ’76 HEI distributor) was set to *37 degrees*, and we were using *91-octane pump gas *with 10% ethanol – right out of the gas station down the street. Total timing was coming in before 2000 rpm – a very quick curve. the engine wanted more timing, so *we bumped total timing up to 41 degrees *and pulled it 2 more times to assure that the data was backed up. The change in timing made a big difference across the entire rpm range, and we had no indication of any detonation, even at wide open throttle under load at 2000 rpm."


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## geeteeohguy (Feb 2, 2008)

First set the dwell to 30 degrees. Then disconnect the vacuum hose and set the base timing at idle to 6--10 degrees BTDC. Reconnect the vacuum line, and adjust the carb idle speed and mixture if needed. That will get you up and running, likely, just fine.


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## geeteeohguy (Feb 2, 2008)

PontiacJim said:


> GTOGUY: "while the 1967 and earlier closed chamber heads do run better with more timing (due to their design) they are unforgiving in a stock engine (flat top pistons) unless you run 100 octane gas. You will rattle your '67 and earlier Pontiac to death trying to run a full factory timing curve on 91 octane fuel."
> 
> PJ: I would agree, but we have had several members tell me/us how they can run 93 octane with the 10.5 compression "067" heads and go with 34-36 degrees total. Not sure how they do it with iron heads, but the last post was from lars:
> 
> ...


Jim, I'm convinced environment has something if not a lot to do with it. Out where I am, it's super low humidity, with dry, hot air. Makes a borderline situation with detonation more sensitive. I've had the same issue with multiple GTO's with stock compression over the past few decades. All were closed-chamber first-gen goats. Guys in more humid parts of the country seem to fair better.


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## MattH (Nov 1, 2020)

geeteeohguy said:


> First set the dwell to 30 degrees. Then disconnect the vacuum hose and set the base timing at idle to 6--10 degrees BTDC. Reconnect the vacuum line, and adjust the carb idle speed and mixture if needed. That will get you up and running, likely, just fine.


Got my meter today, still waiting to pick up some new mufflers. I will try this out and let you know how it goes. Thanks.


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## PontiacJim (Dec 29, 2012)

geeteeohguy said:


> Jim, I'm convinced environment has something if not a lot to do with it. Out where I am, it's super low humidity, with dry, hot air. Makes a borderline situation with detonation more sensitive. I've had the same issue with multiple GTO's with stock compression over the past few decades. All were closed-chamber first-gen goats. Guys in more humid parts of the country seem to fair better.


Altitude is also a big factor which requires higher compression and I think some of these engines/cars must be at altitude. We both know the factory requirement for the high compression cars called for premium gas which was the 98 octane. Retarding the timing way back only gives up a lot of HP IF you can retard it enough not to hit the point were now you get into overheating issues. It is better to build a low compression engine were you can use maximum advance and pull out HP versus a high compression build and have to retard the timing and kill HP.


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## armyadarkness (Dec 7, 2020)

PontiacJim said:


> "67 400 with 670's, Dougs headers, MSD dizzy, Edelbrock 800 cfm carb, 30 over, runs all day on 93, in 98 degree temps with 90% humidity."


This is definitely me. Y'all know how much I drive and I have no issues... aside from the fact that I feel under powered at times. I dont mention it often, because Im not looking to look a gift horse in the mouth.


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## armyadarkness (Dec 7, 2020)

geeteeohguy said:


> Jim, I'm convinced environment has something if not a lot to do with it. Out where I am, it's super low humidity, with dry, hot air. Makes a borderline situation with detonation more sensitive. I've had the same issue with multiple GTO's with stock compression over the past few decades. All were closed-chamber first-gen goats. Guys in more humid parts of the country seem to fair better.


I do live on the east coast, 2 miles from the bay and 2 miles from the ocean


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## armyadarkness (Dec 7, 2020)

PontiacJim said:


> "670's were GTO-only heads in 1967. The flow pretty well, but they're closed chamber heads and usually need quite a bit of timing."
> 
> *lars *- "The engine was a 1976 Firebird 400 – I basically converted it into a 1967 335-horse (gross rating) GTO configuration with the “670” closed chamber, large-valve heads, which ended up producing an actual compression ratio of 10.08:1 with flat-top pistons and the stock deck height. The owner wanted a very mild cam to maintain engine vacuum and power brakes, so a mild hydraulic roller with specs similar to a Ram Air IV was used. No other trick parts – the engine was pretty much a 1967 GTO 400 with a mild roller in it. Total timing (stock ’76 HEI distributor) was set to *37 degrees*, and we were using *91-octane pump gas *with 10% ethanol – right out of the gas station down the street. Total timing was coming in before 2000 rpm – a very quick curve. the engine wanted more timing, so *we bumped total timing up to 41 degrees *and pulled it 2 more times to assure that the data was backed up. The change in timing made a big difference across the entire rpm range, and we had no indication of any detonation, even at wide open throttle under load at 2000 rpm."


Well this is DEFINITELY me, and maybe why I feel under powered is that I set my total to 32. Sounds like I shouldve kept going.


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## armyadarkness (Dec 7, 2020)

MattH said:


> Guys I’m going to be honest, I don’t have a clue what y’all are talking about. I’m used to starting at TDC, point button at #1 wire and fire it up, get your light out and line the scribe up with the 0 or 10 degree mark. I found Lars timing information and decided to give it a shot. Now I wish I never did. Whats the harm in setting time just like I described above plus checking dwell before using the timing light?


Everyone here is going to tell you how to set the optimum curve. However, there's nothing wrong with setting your base timing at 6 degrees BTDC, with your timing light, and calling it a day. Thats what the world has been doing for 100 years.

You came here with a car that wouldnt start, now it does. So... you can keep the microwave that you already won, or you can keep going and try to win that speed boat!


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## Mine'sa66 (Oct 30, 2019)

geeteeohguy said:


> First set the dwell to 30 degrees. Then disconnect the vacuum hose and set the base timing at idle to 6--10 degrees BTDC. Reconnect the vacuum line, and adjust the carb idle speed and mixture if needed. That will get you up and running, likely, just fine.


This^^^^ and the question is are you running your vac can off ported or manifold? You might need to set your base timing a little differently for idle quality depending on which way you're running it.


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## PontiacJim (Dec 29, 2012)

armyadarkness said:


> Well this is DEFINITELY me, and maybe why I feel under powered is that I set my total to 32. Sounds like I shouldve kept going.


*BearGFR *has pointed out here before that the only real way to know if advancing your timing is doing anything is to take it to a drag strip where you can time your car and see how the advance changes your times. If you have it at 32 and bump it to 34 with no change, then it may be good. If you bump to 36 and no change, or it slows, you need to drop it. Some of these builds actually can run better at 30. So if you were to drop the advance to 30 and your car slowed, then you would advance it back up to 32.

You just don't want any pinging/detonation. Intial timing, Timing Curve, Total Timing (mechancal) and at what RPM Total is all in can make a big difference on how the car performs - just takes some work/trial & error.


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## geeteeohguy (Feb 2, 2008)

armyadarkness said:


> This is definitely me. Y'all know how much I drive and I have no issues... aside from the fact that I feel under powered at times. I dont mention it often, because Im not looking to look a gift horse in the mouth.


I haven't been able to run the 670's on my '67 in 30 years. Not at sea level in CA. Had to add water injection and retard the timing, and even that failed. Ended up installing a pair of 1970 #15 455 heads with small valves and converted to screw in studs. 87cc instead of 70-72cc and will just run on 91 octane. It will still ping on a 105 degree day pulling a grade, though, unless I add some real octane booster. Come to think about it, when I drove the car to Yellowstone in the late 80's with high compression, I did not have pinging issues at higher elevations. I had issues in CA and NV where it was still very hot and dry.


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## armyadarkness (Dec 7, 2020)

geeteeohguy said:


> I haven't been able to run the 670's on my '67 in 30 years. Not at sea level in CA. Had to add water injection and retard the timing, and even that failed. Ended up installing a pair of 1970 #15 455 heads with small valves and converted to screw in studs. 87cc instead of 70-72cc and will just run on 91 octane. It will still ping on a 105 degree day pulling a grade, though, unless I add some real octane booster. Come to think about it, when I drove the car to Yellowstone in the late 80's with high compression, I did not have pinging issues at higher elevations. I had issues in CA and NV where it was still very hot and dry.


Yep, I heard you mentioning it the other day, and I didnt comment... In fact, this is my 2nd 67 with the original 400 and 670's, and I never had issues. Although on my first 67 it just had a Pontiac HEI and a Mr Gasket recurve kit, whereas this one has a Pro Billet, so I can tailor each aspect. 

I usually stay out of these timing threads because it sounds like my experience is unique and I didnt want to jinx myself or misguide anyone else. But I do feel better after reading that post from Lars, that Jim put up.


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## armyadarkness (Dec 7, 2020)

PontiacJim said:


> *BearGFR *has pointed out here before that the only real way to know if advancing your timing is doing anything is to take it to a drag strip where you can time your car and see how the advance changes your times. If you have it at 32 and bump it to 34 with no change, then it may be good. If you bump to 36 and no change, or it slows, you need to drop it. Some of these builds actually can run better at 30. So if you were to drop the advance to 30 and your car slowed, then you would advance it back up to 32.
> 
> You just don't want any pinging/detonation. Intial timing, Timing Curve, Total Timing (mechancal) and at what RPM Total is all in can make a big difference on how the car performs - just takes some work/trial & error.


Now that the new cam is in and the rans is done, re-timing and re-jetting are at the top pf my list... If it ever stops raining in Jersey, which isnt likely.


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## geeteeohguy (Feb 2, 2008)

armyadarkness said:


> Yep, I heard you mentioning it the other day, and I didnt comment... In fact, this is my 2nd 67 with the original 400 and 670's, and I never had issues. Although on my first 67 it just had a Pontiac HEI and a Mr Gasket recurve kit, whereas this one has a Pro Billet, so I can tailor each aspect.
> 
> I usually stay out of these timing threads because it sounds like my experience is unique and I didnt want to jinx myself or misguide anyone else. But I do feel better after reading that post from Lars, that Jim put up.


Helped a friend restore his '67 about ten years ago, and it's running the born with 400 with the 670 heads. 4 speed car, 3.55 gears....he has to run 100 octane fuel. He lives near me, where it's low humidity (very) and over 100 degrees maybe 90 days a year. I think geography has a lot to do with it. Cliff Ruggles the Q-jet guru has had great luck over the years running high compression iron headed Pontiacs on pump gas. But he's in a humid area. Back in the '80's I had a 428 in my '65 GTO and never once heard it detonate. Then one day I screwed up a rod bearing over-revving it. When I pulled it apart, 4 or 5 pistons had broken ring lands and the bearings and crank were hammered from detonation. Again, never heard any audible detonation. I think if your advance curve is on the money, and you are not jetted too lean, and it's running 195 or less temp, and you're in the right part of the country, you can pull off running these on pump gas. For me, not the case. And I've been driving first-gen GTO's since the '70's non stop!


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## NYGTO2018 (Oct 1, 2018)

This thread is amusing on many levels but we all consistantly learn and help each other. Love these damn Pontiac's!
As always a big thank you to PontiacJim.
Must have a dwell meter and timing light for basic tuning!
Photo from Nostalgia Drag Day at Island 2 weeks ago. 14.24 @ 99.44 mph (on whitewalls!)
Dwell exactly at 30 and timing at 13 initial!
Thanks :--)


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## PontiacJim (Dec 29, 2012)

NYGTO2018 said:


> This thread is amusing on many levels but we all consistantly learn and help each other. Love these damn Pontiac's!
> As always a big thank you to PontiacJim.
> Must have a dwell meter and timing light for basic tuning!
> Photo from Nostalgia Drag Day at Island 2 weeks ago. 14.24 @ 99.44 mph (on whitewalls!)
> ...



Wow! Now if you could get someone to photo shop out those cars in the background and insert a few era correct cars, you'd have a heck of a nostalgia looking pic of your car "back in the day."


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## NYGTO2018 (Oct 1, 2018)

PontiacJim said:


> Wow! Now if you could get someone to photo shop out those cars in the background and insert a few era correct cars, you'd have a heck of a nostalgia looking pic of your car "back in the day."


You are exactly right. Park the late model stuff away from camera line of sight. Also running were vintage front engine dragsters and many varieties of early 60s iron. A side note: A 389/4bbl GTO can hold up against a 389/3x2bbl if tuned properly IMHO :--)


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## NYGTO2018 (Oct 1, 2018)

Back on point, don't mess with springs and weights until you're dialed in with basics. Keep in mind you might break something big without proper fuel using light springs. Trust me I learned the hard way. My experience is 9° btdc max on a stock 389 YS /WT GTO to stay safe. Dished pistons etc changes the equation of course but my car is stock and my experience. I also use Sunoco 110 at least to keep detonation a non issue at the strip.


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## MattH (Nov 1, 2020)

Alright so I got new mufflers installed and started her up. Checkeddwell and it was waayy of at around 8. Now it’s up where it should be at 31. I set the initial timing at 6 degrees BTDC with the vacuum advance line pulled and plugged. Tightened the distributor up and plugged up vacuum advance. Car idles great for a while then after some revving and driving the idle creeps up to 1k or slightly above and timing is around 12 degrees. Idle screws on the carb don’t seem to make any difference.


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## geeteeohguy (Feb 2, 2008)

Sounds like your mechanical advance weights are staying out in the extended (advanced) position. You can pull the cap and twist the rotor and see if it sticks or feels gummy and doesn't snap back. It's happened to me. The distributor shaft gets gunked up with varnish over time and will hold it advanced. The cure is to disassemble, clean, lube, and re-assemble the distributor. This may or may not be your problem, but you can check it in just a minute.


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## MattH (Nov 1, 2020)

I’ve pulled and reinserted the distributor in my 87 F150 many times but have read a lot of horror stories on people pulling and breaking things on a GTO. I’ll run out and check if the shaft is sticky.


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## MattH (Nov 1, 2020)

1967 Pontiac Distributor


GTO




youtube.com


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## RMTZ67 (Mar 12, 2011)

Nothing wrong with it if gets you on the road until you understand more. Set your dwell to 30. Then set your timing to 6 with the vacuum disconnected from the dizzy and plugged. Take it out and see how it runs.


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## RMTZ67 (Mar 12, 2011)

MattH said:


> I’ve pulled and reinserted the distributor in my 87 F150 many times but have read a lot of horror stories on people pulling and breaking things on a GTO. I’ll run out and check if the shaft is sticky.


 I personally have never broken anything on any of my cars. Get your compression stroke put it on tdc point the rotor where you want and play with it till it drops. In reality it can point anywhere as long as you start number one there and have the room to turn the distributor both ways somewhat. It's just the next guy that gets your car that will say wth, lol. Firing order counter clockwise.


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## MattH (Nov 1, 2020)

I think I’m heading in the right direction. Dwell is at 30, initial timing set at 11-12. It creeps back down under after vacuum advance it’s hooked up but when reving maxs out around 30 degrees. It runs great but idle is too high. The primary flap stays wide open. Car will shut off if I put my hand over the flap, but doesn’t act irrationally if I spray carb cleaner checking for vacuum leaks.


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## RMTZ67 (Mar 12, 2011)

MattH said:


> I think I’m heading in the right direction. Dwell is at 30, initial timing set at 11-12. It creeps back down under after vacuum advance it’s hooked up but when reving maxs out around 30 degrees. It runs great but idle is too high. The primary flap stays wide open. Car will shut off if I put my hand over the flap, but doesn’t act irrationally if I spray carb cleaner checking for vacuum leaks.


Are you saying your timing goes down when you plug in the vacuum hose? And you are removing the vacuum hose at the distributor and plugging it to check timing?


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## MattH (Nov 1, 2020)

Yes I am setting initial with the vacuum advance line pulled and plugged. Seems to move up or down a few degrees once advance is hooked back up and after revving a bit. If normal great, just never dealt with vacuum advance only spout connector.


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## MattH (Nov 1, 2020)

Everything seemed to be steady this evening so took to the road for a couple test runs. Ran and drove smooth. First stop hesitated a little and almost stalled but evened out. 3-4 more passes up and down the road without a hiccup. Got back to the driveway and goosed it one more time and it cut off and I can’t get it to start back up without reving the motor and it’s sounds and feels like it’s missing badly. Anything off the top of your head that I should check.


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## BearGFR (Aug 25, 2008)

MattH said:


> Everything seemed to be steady this evening so took to the road for a couple test runs. Ran and drove smooth. First stop hesitated a little and almost stalled but evened out. 3-4 more passes up and down the road without a hiccup. Got back to the driveway and goosed it one more time and it cut off and I can’t get it to start back up without reving the motor and it’s sounds and feels like it’s missing badly. Anything off the top of your head that I should check.


That sounds like a vacuum leak to me. Check all the connections. If it's a TH400 sometimes the line can come disconnected from the trans vacuum modulator underneath the car. If you have to, disconnect and cap EVERYTHING at the carb or manifold connections, then add them back one at a time. If there's a leak you should be able to find the one that causes the problem.

Timing: 30 degrees "all in" (with no vacuum connected) is a little low. Try 35 or 36 and see how it likes that.

Cheers,
Bear


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## MattH (Nov 1, 2020)

BearGFR said:


> That sounds like a vacuum leak to me. Check all the connections. If it's a TH400 sometimes the line can come disconnected from the trans vacuum modulator underneath the car. If you have to, disconnect and cap EVERYTHING at the carb or manifold connections, then add them back one at a time. If there's a leak you should be able to find the one that causes the problem.
> 
> Timing: 30 degrees "all in" (with no vacuum connected) is a little low. Try 35 or 36 and see how it likes that.
> 
> ...


Haven’t disconnected any vacuum lines yet, but started it today and started right up.. Verified dwell is still at 31, but timing retarded itself about 8 degrees. Set it back to 12 with vacuum line pulled and plugged and drives good again. What are the chances the coil is bad. I know once coils are bad they get hot and things start shutting down.


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## BearGFR (Aug 25, 2008)

If there's no failure mode of a coil that I know of that will cause your timing change. If your timing is changing then something that is not supposed to move is moving. The likely suspects are the distributor is turning in the block, or the breaker plate inside the distributor is moving around, or maybe the timing marks on your balancer are moving because the rubber is shot and the outer ring is slipping. I don't remember what kind of ignition you have, but if it's an electronically triggered system then maybe the module is going bad.


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## MattH (Nov 1, 2020)

BearGFR said:


> If there's no failure mode of a coil that I know of that will cause your timing change. If your timing is changing then something that is not supposed to move is moving. The likely suspects are the distributor is turning in the block, or the breaker plate inside the distributor is moving around, or maybe the timing marks on your balancer are moving because the rubber is shot and the outer ring is slipping. I don't remember what kind of ignition you have, but if it's an electronically triggered system then maybe the module is going bad.


Well unfortunately its acting up again. Will hardly idle and running extremely rich. I also noticed a pooling of fuel on the carb at the accelerator pump arm recently. After the loud BOOM that made me replace the muffler, I’m thinking the accelerator pump is bad again. Going to pull the carb and order a new pump.


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## BearGFR (Aug 25, 2008)

Float level too high maybe?


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