Probably not a popular opinion......BUT, if your motor won't run without what is considered extremely large amounts of spark lead, something in the combo is grossly inefficient.

Don't care whos motor made what, with how much timing. When there are motors with good heads and the right cam profile that make best power at around 30*......if yours needs 40*, it's NOT an efficient motor. If you have an inherently inefficient head design, there ARE cam profiles to help it.

And NO, timing is not just a number. It's a relative gauge of the engines efficiency.

In the OPs case......he has a 60s or 70s at best camshaft profile, with a modern head. Of course it's not an ideal combo

Your running MSD, correct... MSD even suggest to
not use a dial back light... I have seen them off
but some guys say they work fine.... myself I use
the Flaming River 1001
https://www.summitracing.com/parts/fla-fr1001/overview/

Wanted to say it, but was waiting for someone with clout that won't start an argument.

40 degrees....time to hop into the 21st century and say hello to chamber/port/combustion efficiencies in the 20 degree range....don't even get me started on the porting an iron head thread...

What year is the block? with aluminum heads helping cut comp and the block could be your culprit. I chased a problem for close to a year with the e -58 engine I have today I Could not get the car to run a reasonable time I was convinced that timing has to be total of no more then 36-38 degree's In the end after talking to several older mechanics they gave the instructions give it all it will take then if it talks back drop it 2 degree's I have lived with that ever since currently running 45 degree's total and have run as much as 47 with racing gas. Car is not fast but a 7.5 motor running with a backyard rebuild with same pistons has run 14.3 at 96 in a 4300 lb car By the way not real issue to date with timing that high.

My 340 on the other hand does not like more then 34 degree's with 93 octane Use to be able to run near 40 with good old style Sunoco 260 1970

Conclusion do what works its your engine

Check rotor/cap phasing?

Definitely try another timing light. IMO dial backs are garbage.

Had a craftsman dial back forever. It works great

See what I said..some like the dial back... but
yet MSD says DONT USE THEM... that Flaming River
is the best I own. and I have a FEW.. no battery
to hook up.. clip it on the wire(it makes a difference
which way its pointed)

Thats the one I have

I have a couple of timing lights..one Craftsman and one other one. Neither are dial backs. IMO those were made for mechanics working on Hondas and toyotas.
Thinking about a FR light. Just never needed it. But I may get one and check it against what I have.


The OP needs to get a timing light and stick with it. If you pay me to do your tune up, I do it with my timing light because I trust it, and the check it with yours. If the numbers are different then you use YOUR timing light. I don't care if your light says it has 60 total, as long as it repeats. Or you have to get a different light and check the new one.

It's NOT that the cables are made backwards......its because one way is correct for analog and one way is correct for digital. So you check the timing, swap the wires and check it again. The higher reading is the correct connection for a digital box, the lower number is wired correctly for analog. I have seen it be 6* different........so what you read as 41* with a light, may in fact only be 36* or so

Its a 78 block .030 over with speedpro piston .005 inthe hole. With the timing gear lined up dot to dot, I checked the centerline on the cam and the opening and closing of the intake and exhaust lifters. Everything matched up with the cam card. I left it there instead of advancing the cam.
The eddyheads have been gone through by Best Machine, and the MP .557 cam although and old design, plenty of people running them here making power. First run off the trailer the car ran a 12.60 @ 103 mph. Timing at 36. Jetting up on the next pass got me a 12.53 @ 105. Now at 40 degrees I ran a 12.20 @ 109.

Same here !

4 degrees got you 3/10ths & 4mph? You sure your not running crazy lean?

I generally don't bring this up, because NHRA stockers are some of the most scienced out race cars on the planet........BUT it is worth a comparison.

H/SA is where low compression 360 Volares run, that weigh 3500lbs. Stock head castings, stock lift on the shaft, stock intake and other things. The record in the class is bottom 11s at 116 mph. Your car would NEVER be as quick, because it doesn't work like a stocker. But mph is a function of POWER. With alum heads, big cam, better intake and better carb, you are 7mph down. That's a lot of power you are not making, compared to something with a whole lot closer to stock parts than you have.

So whats my point?...........the comment about "plenty of people here running that cam and making power".......OK, but do they make the power they SHOULD. That is the question. Just because so and so makes power with X part, does not mean that's the part YOU need

[/quote]It's NOT that the cables are made backwards......its because one way is correct for analog and one way is correct for digital. So you check the timing, swap the wires and check it again. The higher reading is the correct connection for a digital box, the lower number is wired correctly for analog. I have seen it be 6* different........so what you read as 41* with a light, may in fact only be 36* or so[/quote]

I get the actual timing change in spark output with switching the wires, but I'm not following how 41 would be seen as 36. It seems to me that if the polarity were to be switched, and in fact the timing did drop to 36, wouldn't he now have to bump up the timing to get the engine to run at its best? Not trying to argue, just trying to figure out the end logic.

Thanks 1967dartgt, I thought that was the case,that is why I asked. I have been hoping to get in the 6teens I guess I should move my timing up and see if it helps. I have been running 35* timing. I have been waiting on my 315/60 Radial Pros I ordered from Summit for 6 weeks and now they say it will be the 24th.

I get the actual timing change in spark output with switching the wires, but I'm not following how 41 would be seen as 36. It seems to me that if the polarity were to be switched, and in fact the timing did drop to 36, wouldn't he now have to bump up the timing to get the engine to run at its best? Not trying to argue, just trying to figure out the end logic. [/quote]

On my engine 416 it made the best power at 40*..
he is at 41 but afraid to go higher.. so IF the
wires are backwards at its really at 36* he could
still go higher for peak power and it wouldnt read
47*.. the number would end up lower... he has already
said if he goes higher it runs better.. it needs the
timing.. no matter what the number is... but 47* or
what ever it turns out to be is a high number.... so
IF his light is off AND the wires are backwards that
would mean a lot... also he said he went to 3000 rpm..
if he was a little low that would still have the multiy
spark working... that drops out at 3000 rpm +or-

Spark plug says no

This is JMO.. but you have 2 problems..the wires are
backwards and your light isnt working well with the MDS