What's your best guess?

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Stroked68Dart

Stroked68Dart

402 Crate Motor in a 68
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If you don’t mind please give me your best guess as to what I should set the timing to:

I am getting ready to set the timing on my 402 Mopar crate motor (specs are below). I was given the below timing suggestions as a starting point:

18 degrees at idle
16 degrees at 3200 (34 degrees total)
12 degrees at 12 vacuum

The motor is in a:
’68 Dart
A833 four speed
4:10 rear gear
P225/55/R18 rear tires on 18 inch wheels

The Motor:
Holley 750
Headers are 2 inches I think

4.00" bore/4.00" stroke
9.0:1 compression ratio
Big valve Magnum R/T Cylinder Heads
2.02" intake and 1.625" Exhaust Valves
Heavy-duty Valve Springs
288°/292° duration, 0.501"/0.513" lift Hydraulic Roller Camshaft

Single plane, M1 4-bbl Aluminum Intake Manifold

Double Roller Timing Chain and Sprockets
8-quart center sump street/strip Oil Pan

MSD Blaster 2 coil
MSD E-CURVE distributer

If you would like to see a couple of videos of the car see the below links.

Videos of Dart are here

Thank you for your time and help.

Bill

magnum402-jpg.jpeg
 
Last edited:
The answer is right there. They told you all in 34 degrees then set it all in to 34. I personally find MoPars like 37- but not always.
 
I would try connecting the VA to a manifold vac source.
That will give it 30* at idle. It will more than likely like that [ rpm will increase ] because of:
- the low CR
- the single plane intake
- the sizeable cam
 
Bewy said:
I would try connecting the VA to a manifold vac source.
That will give it 30* at idle. It will more than likely like that [ rpm will increase ] because of:
- the low CR
- the single plane intake
- the sizeable cam
Click to expand...
This ^^^^^^ is probably a good starting point. That's a LOT of cam for "just" 9:1 compression. Maybe run a cranking compression test and report back with that and we can nail it down even better. My guess is it will want a lot of initial timing.
 
Ehhhh, grandma might not like it….

:lol:
 
I would probably go with 12 initial to start out, And go from there. Oh yeah congratulations on that crate that's awesome!
 
Actually i like what was recommended. You have lots of cam, gear, and a four speed, so an aggressive timing curve should be fine. I see you have a e distributor so you can set the curve where you want. If you hear detonation, slow it down a bit.
The magnum heads have a faster burn chamber than the old style LA, so less total is needed. I might try 32 total to start with, then see if 34 or 36 is an improvement. If not, and i dont think it will be, i would go back to 32.
 
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