timing and towing

[mtjeeper]

Howdy,
I have a quick one here,

I recently gave the Jeep a tune up and it occured to me that maybe my timing could be tweeked for better towing performance

360/tf727auto, performer intake, Qjet800, Jacobs ignition / coil, MSD Pro-billet dist. I also run 35" MTR's on an 8" lift.

The Haynes manual calls for 19*BTDC and I can change out the springs in the MSD dizzy. Normally I have the timing aroung 12*btdc.
Which would help towing in the mountains, advancing the ignition or retarding it??

Any suggestions on a timing setup that would help towing?
economy is secondary to power.

Thanks,
matt

[mbopp]

The more timing advance you can run the more power you'll get. But you have to have an ear tuned for pre-ignition or knock, especially when towing. You'll have to decide yourself if running more advance & premium gas is worth it.

[pershingd]

I'd set it at what the specs are and listen for predetonation (ping). If it pings you can retard the timing until it stops or use premium unleaded.

Is the 360 built up or stock? If stock, I doubt you'll have any problems using the factory timing specs - but I'd double check the timing spec with another source because 19 degrees sounds like too much lead timing for a 360.

JMHO,
David

[no_draws]

Howdy,
I have a quick one here,

I recently gave the Jeep a tune up and it occured to me that maybe my timing could be tweeked for better towing performance

360/tf727auto, performer intake, Qjet800, Jacobs ignition / coil, MSD Pro-billet dist. I also run 35" MTR's on an 8" lift.

The Haynes manual calls for 19*BTDC and I can change out the springs in the MSD dizzy. Normally I have the timing aroung 12*btdc.
Which would help towing in the mountains, advancing the ignition or retarding it??

Any suggestions on a timing setup that would help towing?
economy is secondary to power.

Thanks,
matt

One idea might be to try a smaller carburetor. The q-Jet you listed could be an issue. Do a google search for engine math or something like "how to determine carburetor cfm" and you should find some links that describe how to size a carb to your combo. Engine cubic inches and expected RPM range determine the CFM needed from the carb. For example my other hobby is drag racing and I have a 400ci small block chevy motor that turns RPMs up around 7800. I only run a 750cfm carb. It is custom built for my application to flow more than 750 but the base unit is still the same. Your 800 cfm could be causing a little power loss as well as fuel economy problems. If you can find a local carb shop, give them a call and see if they have a 750 you can borrow. Also, your QuadraJet is probably a spread bore, I would swap it out for a square bore carb mainly because you get bigger primaries which are what your using when cruising down the freeway. Just my opinion.

What gears do you have in the Jeep? It might be a good idea to step it up with those tires.

[SpeakEasy]

360/tf727auto, performer intake, Qjet800, Jacobs ignition / coil, MSD Pro-billet dist. I also run 35" MTR's on an 8" lift.

The Haynes manual calls for 19*BTDC and I can change out the springs in the MSD dizzy. Normally I have the timing aroung 12*btdc.

Are you speaking English?

[aw738]

Quote:
--------------------------------------------------------------------------------
Originally Posted by mtjeeper
360/tf727auto, performer intake, Qjet800, Jacobs ignition / coil, MSD Pro-billet dist. I also run 35" MTR's on an 8" lift.

The Haynes manual calls for 19*BTDC and I can change out the springs in the MSD dizzy. Normally I have the timing aroung 12*btdc.

--------------------------------------------------------------------------------


Are you speaking English?

This makes perfect sence to me.  I'll try to translate.

Engine size: 360 cubic inches of displacement
Torque Flight 727 automatic transmission
Edelbrock aluminum Performer intake
Quadrjet 800 cubic feet per minute carburetor
Jacobs electronic ignition module
Multiple Spark Discharge distributor
Micky Thompson radial tires that are 35" in diameter
Spark plugs fire at 19 degrees before the piston reaches top dead center
dizzy = distributor