MSD 8361 initial timing setup
Thread Starter
Burning Brakes
Joined: Jan 2003
Posts: 961
Likes: 275
From: Frederick MD
MSD 8361 initial timing setup
Hoping to get the 68 running again for the first time in 3 years today (hopefully). In summary the engine itself is a mid 70s 454 out of a truck with peanut port heads on it. Smog motor. As best I can tell it’s either got a very small cam (RV style) or stock. No porting on the heads and the pistons are a dish style. Compression on a compression gauge was around 140ish which lends me to think that at best it’s a stockish rebuild if not a totally OE motor. Around 8:1 static compression, but without pulling the motor apart that’s about the best I can tell with a bore scope and deductive reasoning.
Motor didn’t run very good and stumbled upon takeoff etc when last ran. The following definitely in my mind were not helping:
1. Had a tarantula single plane intake manifold on it (rectangle ports) which has a RPM range which just starts to come in where the peanut port heads would kill it off.
2. Mallory unillite distributor with no vacuum advance and no idea what the timing is was inside.
Car has an aftermarket hood so I picked up a used Edelbrock 2161 intake for pretty cheap. Got a helva deal on the entire MSD setup for a 8361 (box, 2x coils, dizzy) for $150. Definitely overkill for this motor but for what I paid I couldn’t go wrong. Gentleman that sold it said it had about 10 hours of run time (everything looked new) and pulled it off because he couldn’t get the motor to time right. Basically the timing would jump around for no apparent reason. Took one look at the dizzy and even without any measuring tools knew what was wrong. The dizzy had close to .070 - .080 of endplay. While I’m no engine master I know that will cause the timing to jump around particularly knowing the dizzy gear is helically cut.
With the above said. I’m starting out with the blue bushing in the distributor and a light blue and light silver spring on the dizzy. I figure these will be safe starting points given I’m not 100 percent on what the motor is. Any suggestions on where I’m likely to end up? I’ve read the Lars paper and all that fun stuff. Based on the paper I could go with both blue springs and a slightly smaller bushing but just see where other folks have ended up with similar setups.
Definitely not my first time retiming a dizzy but this is my first time messing around with the curve so wanted to ask questions.
Motor didn’t run very good and stumbled upon takeoff etc when last ran. The following definitely in my mind were not helping:
1. Had a tarantula single plane intake manifold on it (rectangle ports) which has a RPM range which just starts to come in where the peanut port heads would kill it off.
2. Mallory unillite distributor with no vacuum advance and no idea what the timing is was inside.
Car has an aftermarket hood so I picked up a used Edelbrock 2161 intake for pretty cheap. Got a helva deal on the entire MSD setup for a 8361 (box, 2x coils, dizzy) for $150. Definitely overkill for this motor but for what I paid I couldn’t go wrong. Gentleman that sold it said it had about 10 hours of run time (everything looked new) and pulled it off because he couldn’t get the motor to time right. Basically the timing would jump around for no apparent reason. Took one look at the dizzy and even without any measuring tools knew what was wrong. The dizzy had close to .070 - .080 of endplay. While I’m no engine master I know that will cause the timing to jump around particularly knowing the dizzy gear is helically cut.
With the above said. I’m starting out with the blue bushing in the distributor and a light blue and light silver spring on the dizzy. I figure these will be safe starting points given I’m not 100 percent on what the motor is. Any suggestions on where I’m likely to end up? I’ve read the Lars paper and all that fun stuff. Based on the paper I could go with both blue springs and a slightly smaller bushing but just see where other folks have ended up with similar setups.
Definitely not my first time retiming a dizzy but this is my first time messing around with the curve so wanted to ask questions.
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Go time it and see how it runs. If it doesn't feel right, tweak. No right answer as each engine combo will be different. May never run right if too many engine parts are mismatched as you have already noted.
Le Mans Master
Joined: Oct 2010
Posts: 6,936
Likes: 848
From: melbourne florida
2023 C3 of the Year Finalist - Modified
First. Don't start off calling a distributor a "dizzy".
That engine sounds so mis matched it isn't even funny.
You may need to pull the timing chain cover to see what's up.something tells me the guy you bought it from left you his problem. It could be a flat cam lobe . I'm afraid if setting the timing doesn't help you will need to dive deeper. Good luck.
That engine sounds so mis matched it isn't even funny.
You may need to pull the timing chain cover to see what's up.something tells me the guy you bought it from left you his problem. It could be a flat cam lobe . I'm afraid if setting the timing doesn't help you will need to dive deeper. Good luck.
Le Mans Master
Joined: Oct 2010
Posts: 6,936
Likes: 848
From: melbourne florida
2023 C3 of the Year Finalist - Modified
First. Don't start off calling a distributor a "dizzy".
That engine sounds so mis matched it isn't even funny.
You may need to pull the timing chain cover to see what's up.something tells me the guy you bought it from left you his problem. It could be a flat cam lobe . I'm afraid if setting the timing doesn't help you will need to dive deeper. Good luck.
That engine sounds so mis matched it isn't even funny.
You may need to pull the timing chain cover to see what's up.something tells me the guy you bought it from left you his problem. It could be a flat cam lobe . I'm afraid if setting the timing doesn't help you will need to dive deeper. Good luck.
Tech Contributor
Joined: Aug 1999
Posts: 14,379
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
You can't call it that if you're an American. If you do, you will be shipped off to the penal colony called Australia. And we even give those guys crap about calling it a silly name like that. And if you start talking about your "carby" it's highly likely that you'll be banished from the Forum and from this country.
Lars
Last edited by lars; Nov 14, 2021 at 12:49 PM.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
The blue bushing pulls 21 degrees so set initial to 15 degrees to get 36 total. The one silver, one blue spring is a good baseline.....
Adjust the vacuum advance can to pull 12 degrees.....MSD cans are adjustable but they tell you that nowhere....
Jebby
Adjust the vacuum advance can to pull 12 degrees.....MSD cans are adjustable but they tell you that nowhere....
Jebby
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Le Mans Master
Joined: Oct 2010
Posts: 6,936
Likes: 848
From: melbourne florida
2023 C3 of the Year Finalist - Modified
I'm sorry if that happened but I think it's important to use the correct terms so there is no confusion going forward.hopefully he got his issue resolved.
Thread Starter
Burning Brakes
Joined: Jan 2003
Posts: 961
Likes: 275
From: Frederick MD
Didn’t run me off at all LOL. Just reading, taking notes, and working on the car. As for calling it a dizzy…. That’s what my granddad called them on the old gas tractors so that’s what I call ‘em (I’m an old farm kid).
So where I ended up was about 35 degrees advanced at 3500. The advance at idle is 8-10 or so at 650. That’s alittle more advance than what the blue bushing says, but MSD says the bushings are approximate take that for what it’s worth I guess. Springs and bushing are what I set them to on the bench. Vacuum advance was obviously unhooked when I checked. I know
I could have gotten alittle more aggressive I think but it’s my brothers car. He says he’s gonna run 87 octane in it most likely (why I have no idea). So I wanted to be certain it was safe given everything has wise here is either E10 or E15. Seems to run pretty good.
So where I ended up was about 35 degrees advanced at 3500. The advance at idle is 8-10 or so at 650. That’s alittle more advance than what the blue bushing says, but MSD says the bushings are approximate take that for what it’s worth I guess. Springs and bushing are what I set them to on the bench. Vacuum advance was obviously unhooked when I checked. I know
I could have gotten alittle more aggressive I think but it’s my brothers car. He says he’s gonna run 87 octane in it most likely (why I have no idea). So I wanted to be certain it was safe given everything has wise here is either E10 or E15. Seems to run pretty good.