Towing Tune Question

jerodr · #1 Mon, December 22nd, 2008, 09:09 PM

I have a question about towing with the 87 or 93 octane tunes. Is there a limit on what you can tow with these tunes...or can you not tow with them at all? Basically I'm wondering if I should buy a custom tow tune to tow my 2000lb boat or is that not enough weight to make a difference?

Jerod

Northern Supercrew · #2 Mon, December 22nd, 2008, 09:48 PM

i don't think that weight will be a problem for a perf tune if you have one. i have a 87 tow tune, but haven't even tried it out yet. 2 feet of snow here and i ain't got anything to tow:weeping: hopefully bill will clear that up for you.

jerodr · #3 Mon, December 22nd, 2008, 10:03 PM

Honestly I probably never would have even thought about it but my buddy put a hypertech programmer on his 7.3L a couple years ago and I remember in the manual it specifically says DO NOT TOW ANYTHING IN PERF MODE. I figured it might be ok because the gas tunes are milder than the diesel tunes(100hp).

***Jackpine*** · #4 Mon, December 22nd, 2008, 10:45 PM

I suspect you could tow a 2000#, low profile boat with just about any old tune.

According to Bill, the canned tow tune was really not designed for me either. I pull a 3600#, low-profile, HI-Lo travel trailer and Bill wrote a custom tune specifically for that job. I don't really know what the "cutoff" would be in terms of towing weight between a tow tune and a performance tune, but I imagine it would be fairly close to what you tow.

I'm trying to figure out where the damage would come from using a performance tune for towing. Possibly, the transmission would be constantly shifting or the torque converter would be constantly going in and out of lock? I don't really think you damage an engine by "lugging" it now and then.

Bill, of course is the expert here - not me.

- Jack

***Power Hungry*** · #5 Tue, December 23rd, 2008, 05:34 PM

Quote:

Originally Posted by JackandJanet

I suspect you could tow a 2000#, low profile boat with just about any old tune.

According to Bill, the canned tow tune was really not designed for me either. I pull a 3600#, low-profile, HI-Lo travel trailer and Bill wrote a custom tune specifically for that job. I don't really know what the "cutoff" would be in terms of towing weight between a tow tune and a performance tune, but I imagine it would be fairly close to what you tow.

I'm trying to figure out where the damage would come from using a performance tune for towing. Possibly, the transmission would be constantly shifting or the torque converter would be constantly going in and out of lock? I don't really think you damage an engine by "lugging" it now and then.

Bill, of course is the expert here - not me.

- Jack

Jack, you're doing fine.

Where we run into a problem with heavy towing (2500+) on a performance tune has more to do with cylinder temps being slightly higher because of the slight modifications to the fuel curve. I wouldn't necessarily say it does any "damage" to pull in a performance program, it's just not the ideal situation.

High performance applications are leaned out slightly to achieve good top-end power. Tow tunes run a little richer for improved low-RPM torque and lower cylinder temps under sustained heavy loads.

Of course, there are shift changes and timing changes but that has a lot less to do with it than you'd think.

Anyway, as you've already guessed, 2000 to 2500 lbs is about the limit for a performance program before I'd switch to towing.

Hope that clears it up a little.

***Jackpine*** · #6 Tue, December 23rd, 2008, 05:53 PM

Very nice response, Bill. Makes perfect sense and tells me why we have towing tunes to begin with.

Thanks for giving us the "expert's" opinion!

- Jack

Dfishrmn · #7 Wed, December 31st, 2008, 10:20 AM

Quote:

Originally Posted by Power Hungry

Jack, you're doing fine.

Where we run into a problem with heavy towing (2500+) on a performance tune has more to do with cylinder temps being slightly higher because of the slight modifications to the fuel curve. I wouldn't necessarily say it does any "damage" to pull in a performance program, it's just not the ideal situation.

High performance applications are leaned out slightly to achieve good top-end power. Tow tunes run a little richer for improved low-RPM torque and lower cylinder temps under sustained heavy loads.

Of course, there are shift changes and timing changes but that has a lot less to do with it than you'd think.

Anyway, as you've already guessed, 2000 to 2500 lbs is about the limit for a performance program before I'd switch to towing.

Hope that clears it up a little.

Does this pertain to loads in the bed of the truck? I infrequently load the truck 1500-1800# for short trips (25-50 mi) Is this safe in the 87 Performance tune or should I switch to Tow.