Need to stabilize my timing: How?

I currently am running a Mag off a front gear drive (angled up - not direct) and no crank trigger. Timing looks horrible. I assume cam end-play among other things allows the timing to bounce around.

So I want to nail down the timing. I have internally balanced blown BBC with no harmonic balancer.

So I have two choices I know of:

1) A Dual front offset drive for the Mag and the fuel pump.

2) A new hub, degree ring, crank trigger pickup and bracket etc. - likely from RCD.

It looks like about $700 either way, so price isn't really the issue. Which of the two options is the better choice? Why?

Thanks in advance.

Matt

 

cam end play

Fix the problem where the problem is. Get the end play out of the cam. Are you using a Summers Bros off set drive ?

 

In the end you will still need a crank trigger.

 

Get the front mount offset drive from Rcd. I had it on both my hemi and Chevy. You could run mag only with very little movement like 1 degree or 2. But depends on your tune too if your close to the edge then yes either way you'll need a crank trigger

 

Crank trigger vs Mag trigger

I set my cam endplay at as close to zero as I can get it on a cold motor. I know that as the block (aluminum) expands the steel cam doesn't lengthen as much. My Mag triggered timing still varies by 2-3 degrees. You can see that with a timing light- the mark is 2-3 degrees wide but the crank trigger mark is only 1 degree wide. Taking the endplay out of the cam is easy with shims on your fuel pump drive but the ultimate fix is the crank trigger. Dave Germain

 

Great responses everyone. I think I'll just go to RCD for a crank trigger setup.

Thank you!!

 

Get your trigger from Leahy.
www.electrimotion.com

Brandon Booher
NHRA TAD #323
Torque MGMT. - Owner

 

I've looked on their site but can't find anything that looks like a degree wheel w/magnets, etc. Am I missing something?

 

What brand of mag do you have ?

Mallory or MSD ???????

 

Promag 12LT. Yes - I know that's not very ideal. On the upgrade list.

 

Sorry, not trying to hi-jack here, was just curious if you had a Mallory !

 

We use the RCD crank hub and offset mag drive, We ran a MSD 12 for 7 or 8 years changed to a 20 never had a problem yet.

 

Just to close off the issue: We installed an 8973 ProMag Ignition and added an RCD crank hub and degree wheel along with a Leahy pickup.

Promptly ran personal bests of 4.182@171.6 and a 6.54@212.1 on another pass.
(I know those numbers aren't great for this forum, but they were good for me).