Timing Nightmare

[Gearhead10]

We got the 29 runnin and engine broke in a couple weeks ago. Havin a problem though. I can't get it timed right. I been around sbc engines all my life and this is the first time I've ever encountered this. I want to set it around 12 degrees as a startin point but It'll barely run. As I advance the dist it will smooth out but then the timing is way off the tab, like at 28-30 degrees. Now I've done all the checkin like: timing tab, harmonic balancer spun, TDC, we've moved the dist ahead and back a cog, etc. The dual point has a mechanical advance that is adjustable and I've already found out it was already adjusted wide open, which I've read is about 28 degrees. I now believe it should be 0. Put it back together and I can get it to run but still have a timing issue. I went to Mallory website and got alot of info but none seemed to help so far. For one thing I can't find the part # of my dist so I don't know if it is really old or what. There is a new Mallory Unilite unit in sight ,which I'm pushin for, but I would hate to spend that kinda money on a new distributor and still have the same problems. We are stuck to using a smaller dia dist because of the 3 duece setup. I guess the ? I have is am I missing something? Is the dist junk or am I just not gettin the right combination of adjustments. If I can get some info from some of you it would be cool. I just wanna know if this other dist is bad , just maladjusted or if I'm just goin crazy. Thanks

 

[42chevy]

Are you sure the point plate isn't moving? I have had them move and cause what you are describing. Very frustrating to troubleshoot.

 

[zzrodder]

It sounds like the disributor is haywire to me... For a cheap test get an HEI from the boneyard to try, or borrow one from a buddy - or is there not enuf firewall clearance? Unless you are dedicated to going old school I'd take electronic any day over points....

 

[PORTnPOLISH]

Everything you named was exactley what I was thinking but from what I do know about old school points ignition it sounds like 42 may be right. Good luck and keep us posted on what you find.

 

[Gearhead10]

When I had it apart it seemed to have everything tight as it should be. Firewall and intake clearance is the issue with not being able to use a normal HEI unit. I personally hate the point type dist as it is and think a Unilite will be the answer. The ol man has an old racin buddy who is gonna tear down the dist we got to make sure its ok. I'll keep ya posted.

 

[bob w]

Keep in mind there are two balancers with the timing mark in different locations. The balancer used with the "gunsight" timing tab that is practically vertical is different. If you use that balancer with a normal, early timing tab it will appear that the timing is advanced way past the tab in order to get it to run right.

 

[Gearhead10]

The engine is a 283 and using the stock balancer. We had another balancer off a spare 283 and they are both the same. Last night the ol man bumped her up to true top dead center by watchin the piston in #1 hole with a penlight and the marks on balancer are nuts on with the tab. We got a new unilite dist ordered and should be here tomorrow. We'll know by Thurs nite if we got the problem solved I guess. I'll let ya know. Got the torque thrust wheels mounted on her too so we are dang close to drivin it.

 

[cking894]

By any chance did you get the cam timing off? I accidentally did this one. There was a dot on the new top gear that I thought was the correct one. I got the engine running and it sounded really health but wouldn't get out of it's own way. You might try pulling a valve cover and see if the valves are closed all the way when it's at tdc.

Just a thought, Keith

 

[Gearhead10]

Well, we got the new Mallory Unilite dist in and wired yesterday and got her runnin and timed. Its a non-vacuum advance unit but has a preset mechanical advance. Settin timing is tricky but you can really dial it in. It come preset around 16 degrees. So to time it we figured that if we wanted a total timing advance of 28degrees at road speed than we would need around 12 at idle. We have a timing light with a dial on it to preset advance. We set it at 28 and set idle timing at 12. We had to rev it up to 2000 rpm and check total time an it was on 28. We figured we would drive it and see how it runs, if it pings then we need to back the timing down. There is a cruise coming up the 19th for our towns annual summer celebration so we are pushin to get it on the road. The interior isn't done but a blanket on the seats will work. I gotta adjust the clutch linkage this week and she should be road worthy. I get her out I'm gonna post some picks so you can all see the finished product.