timing trouble

bowtie44s · Newbie Joined: 13 May 2012 Posts: 16 772.34 points

I have built 2 engines, a 383 and a 454. They both run pretty good. I couldn't get the timing right on either one, so I timed them by ear. When I put the light on the timing is reading around 60 degrees.

I must be doing something wrong but have no idea what. I checked true TDC by using a piston stop and rotating clockwise, put a mark then ccw and put a mark and scribed the middle of the 2. One motor was right on, the other was 2* off. I have the firing order 18436572, have timing light on #1 plug wire, yes i'm on #1. I have tried 3 distributors on one motor and I tried 3 timing lights, 2 of the lights showed the same, one showed 3* different.

If it really was 60* I don't see how it could actually run, let alone start. If I slow the timing down to where it should be it dies before I get there. What am I doing wrong? It must be me because it's 2 motors and 3 lights.

bowtie44s · Newbie Joined: 13 May 2012 Posts: 16 772.34 points

I also had the vac advance unhooked. When I rev it up it does advance more but I completly lose the mark so have no idea where it is.

SMOKEmUP · Posted: Thu Nov 15, 2012 12:34 pm Post subject:

How are you checking the advance? From the timing light? Or marks on the balancer?

clay · Posted: Thu Nov 15, 2012 4:00 pm Post subject:

It is possible to run at 60* depending on a couple of factors. What is the cranking compression, cam specs, compression ratio and piston design (large dome or flat)? Clay

Paul P · Posted: Thu Nov 15, 2012 6:21 pm Post subject:

Find TDC with a positive stop device in the spark plug hole on the #1 piston. Verify timing mark on balancer. If incorrect get timing tape and install it so you have a known good timing mark reference. Then try timing the engine.

SMOKEmUP · Posted: Thu Nov 15, 2012 7:15 pm Post subject:

af2 · Posted: Thu Nov 15, 2012 9:12 pm Post subject:

10sec.et · Posted: Fri Nov 16, 2012 1:10 am Post subject:

ive noticed this only seems to happen on Chevys. im not throwing rocks, im just sayin. i see these every so often at work. it has to be a balancer issue. its ALWAYS on a rebuilt engine with a factory type balancer. either that or something really wrong in the build.

if you had the piston way down in the hole, would the decreased compression cause it to be such a turd that it actually needed 60° advance ? what about a cam thats a couple teeth off on the timing chain ?

89Gmcsierra · Posted: Fri Nov 16, 2012 6:13 am Post subject:

Car vs truck timing marker is in different location. truck behind waterpump and car is from the side. my friends car had some cheap chrome one on the outside and it was completely off.

Big Dave · Posted: Fri Nov 16, 2012 7:42 am Post subject:

Chevy has made far too many different timing marks. It started with the crankshaft with the pre '64 having the keyway in the crank 20 degrees advanced if used on a '64 and up crank, removable timing tabs (three different versions), three different diameter dampers, tubes and pointers or tabs welded to the timing cover that do not interchange and as noted above even different sides of the engine being used to time the engine because of emission and accessories making the motor hard to find.

Big Dave

bowtie44s · Newbie Joined: 13 May 2012 Posts: 16 772.34 points

I have been working with the big block most recently so I will give you specs on it. I have used 3 timing lights, 1 has the dial. I have an 8" balancer with 8" timing tape. Every method shows the same thing.

The small block has a pretty big solid lifter cam. The big block has a milder hydraulic cam. Here are the specs: lift .500/.500 duration at .050 218int/228exh lsa 114.

The small block is a complete rebuild. Bored .030 and all new rotating assembly. The big block was just a cam head and intake. The short block is still all stock. All I did was check the bearings and obviously had the balancer off.

They both run GREAT i would just like to know what the actual timing is.

clay · Posted: Fri Nov 16, 2012 11:36 am Post subject:

bowtie44s · Newbie Joined: 13 May 2012 Posts: 16 772.34 points

I will check the compression. What should a big block be? The small block should be a little higher since it's 9.7:1.

Like I said, I used 3 different timing lights, they all showed the same thing.

clay · Posted: Fri Nov 16, 2012 11:02 pm Post subject:

I would expect it to be in the 150 - 180 range. Probably closer to the 150 end. With the cam specs you have listed, it should work with a dish piston which is what I'm guessing is in it since you said it was just a cam swap. I still can't come up with anything but I'll keep thinking. If you figure it out be sure to let us know. Clay

bowtie44s · Newbie Joined: 13 May 2012 Posts: 16 772.34 points

Yes they are dish pistons. I will let you know but i'm out of ideas. I did check 6 a while back. It was like 1.5 or 2 degrees different. I don't remember which way. I just assumed that was chain slack or something. It's a brand new cloyes double roller but i'm sure there's a small bit of slack in them. I don't think 2 degrees would be any type of hint to anything. I've about got a raw spot on my head from where i've been scratching it so much. They both run good so i've just about gave up.

I told a buddy that builds dirt track motors to set the time. He said why can't you, i said just see what you come up with. He did use one of my lights. He was under the hood for 15 minutes and he said I HAVE NO IDEA WHAT'S GOING ON.