1974 454 Timing????
Thread Starter
Instructor
Joined: Oct 2005
Posts: 244
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From: Brighton Michigan
1974 454 Timing????
Guys,
Let me set this up quickly for everyone. I have a stock 454 in my 74. I'm running MSD ignition, and last year my mechanic had it running good and it had a very nice idle to it. He claimed that the car needed a harmonic balancer. Due to my inability to get the car too him again to have the balancer replaced. I took it to another reputable shop. I just got it back from the shop where they claimed that the car doesn't need a balancer and they re-timed the car.
Now when I cruise at 40mph, I can't get the car to settle down, she seems to keep pulling intermittenly. Now while at idle it sounds like I have an exhause leak, and when standing behind the car the rumble from the pipes doesn't sound smooth. Is this a timing issue? Let me know guys.
Alex
Let me set this up quickly for everyone. I have a stock 454 in my 74. I'm running MSD ignition, and last year my mechanic had it running good and it had a very nice idle to it. He claimed that the car needed a harmonic balancer. Due to my inability to get the car too him again to have the balancer replaced. I took it to another reputable shop. I just got it back from the shop where they claimed that the car doesn't need a balancer and they re-timed the car.
Now when I cruise at 40mph, I can't get the car to settle down, she seems to keep pulling intermittenly. Now while at idle it sounds like I have an exhause leak, and when standing behind the car the rumble from the pipes doesn't sound smooth. Is this a timing issue? Let me know guys.
Alex
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Joined: Nov 2012
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From: Irma Northern WI
Hi Alex, If the harmonic balancer is defective it generally causes the outer ring to move or slip on the elastomer. That can make timing the car difficult. However; from your description of the problem, I would first replace the spark plugs and then the wires before looking for other causes. Always, the simple things first. If the car sat for long it could also be stale gasoline. Avoid ethanol contaminated gas if possible! good luck.
Thread Starter
Instructor
Joined: Oct 2005
Posts: 244
Likes: 1
From: Brighton Michigan
I had the plugs and wires replaced no more than six months ago. Like I said, it was running fine until it was allegedly retimed. I'm going to try and put a timing light on it soon.
Safety Car
Joined: Mar 2007
Posts: 3,652
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From: Bridgewater nj
If the timing was set last year and no one messed with it since, its still in the same spot! If your balancer slipped, you'll have to time it by ear and feel. I usually keep advancing until it pings. Then back off a degree or two. A good test for pinging is a slight hill cruising in high gear.
If you're surging I would think carb. Or fuel pressure.
If you're surging I would think carb. Or fuel pressure.
Burning Brakes
Joined: Feb 2012
Posts: 925
Likes: 7
If the timing was set last year and no one messed with it since, its still in the same spot! If your balancer slipped, you'll have to time it by ear and feel. I usually keep advancing until it pings. Then back off a degree or two. A good test for pinging is a slight hill cruising in high gear.
If you're surging I would think carb. Or fuel pressure.
If you're surging I would think carb. Or fuel pressure.
Thread Starter
Instructor
Joined: Oct 2005
Posts: 244
Likes: 1
From: Brighton Michigan
No. In my original post. I said the 2nd shop attempted to re-timed the car. I just took it out for a small drive and after I get up to speed (40-50mph) and let off the gas she'll backfire a little. I'll try to get the timing light on her tonight after I get the kids in bed. I'll post updates soon.
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Melting Slicks
Joined: Apr 2001
Posts: 2,030
Likes: 363
From: Lubbock Texas
Sounds like the 2nd shop messed up your tune somehow. You might take it back and give them a chance to make it right but your best option might be to return to the original mechanic who had it running good in the first place.
DC
DC
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Joined: Oct 2005
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From: Brighton Michigan
Gentlemen,
All is good in Michigan. I got the timing light on her and she was WAY to advanced. I retarded her down to 12, and set the fast idle at 850ish. She drives great now. No more surging. One last question...it still sounds like I've got an exhaust leak coming from the drivers side, any thoughts???
All is good in Michigan. I got the timing light on her and she was WAY to advanced. I retarded her down to 12, and set the fast idle at 850ish. She drives great now. No more surging. One last question...it still sounds like I've got an exhaust leak coming from the drivers side, any thoughts???
Melting Slicks
Joined: Jul 2009
Posts: 2,091
Likes: 40
Gentlemen,
All is good in Michigan. I got the timing light on her and she was WAY to advanced. I retarded her down to 12, and set the fast idle at 850ish. She drives great now. No more surging. One last question...it still sounds like I've got an exhaust leak coming from the drivers side, any thoughts???
All is good in Michigan. I got the timing light on her and she was WAY to advanced. I retarded her down to 12, and set the fast idle at 850ish. She drives great now. No more surging. One last question...it still sounds like I've got an exhaust leak coming from the drivers side, any thoughts???
GREAT! News.
My advance was set to high as well. The sticker calls for 10 degrees . Mine was bucking/surging at low RPM too . Its really hard to get a light on a Loaded LS4 with all the belts. Smooth as silk now.
I know my carb needs a total overhaul, the parts rattle like an old worn winchester lever action rife. Maybe this winter. Too much fun driving now.
Heel & Toe
Joined: Jun 2013
Posts: 17
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From: Caracas Miranda
Hi peeps, it is hard unless you put it on a lift or drive it up in ramps or jack stands get under it after starting it a inspect the full exhaust lengh, check the joints between manifolds, muflers and exhaust pipe, use a cut up in flecles sheet of paper and it will flicker when you go by a exhaust leack and you can confirm with a piece of hose to your ear, once you isolate the leak, then can figure out the remedy, my 2 cents, hope it helps and good luck