Thought id get some input quick. Im going this weekend to pick up a 1998 24V truck that dont currently run. I dont have gauges yet and im not sure i should tow that heavy beast home? Its a 2 hr drive one way with a few good hills in between. Also i will be parting the truck out. If  anyone has requests let me know.

Are you making a lot of smoke when you are under acceleration to any serious degree or towing heavy? 

Timing will impact EGTs. Typical cruise timing should be about 19 to 20 degrees for 2,000 RPM. This will vary a bit truck to truck. Higher timing typically makes cooler EGTs. Being your using the MM3 you might need to tweak your tune.

Edited November 29, 20186 yr by Mopar1973Man

27 minutes ago, Max Tune said:

So I guess if what I'm reading in various posts is exhaust pipe temp rather than exhaust manifold temp then I'm in the ballpark.

Someone correct me if I am wrong but the manifold temp is what to pay the most attention to so know whats happening inside the engine.

Edited November 29, 20186 yr by dripley

Manifold temperature so you don't melt a piston. Aluminum melts at about 1,281°F. After the turbo is going to be much lower in temperature.

But pistons aren't made out of aluminum, it's some sort of mix of alloys. I heard that our motors were designed to run 1200 continously and plenty of people got it to 1600-1800 for short time. Not saying it's the thing to do but it's been done. I usually try to stay below 1200 but before I knew much have towed up longer hills with 1200+ for a while, I now downshift and slowdown. Not just for engine but transmission too.

3 hours ago, LiveOak said:

Are you making a lot of smoke when you are under acceleration to any serious degree or towing heavy? 

 

Only if I go to Max tune....(swidt)

1 hour ago, Dieselfuture said:

But pistons aren't made out of aluminum, it's some sort of mix of alloys. I heard that our motors were designed to run 1200 continously and plenty of people got it to 1600-1800 for short time. Not saying it's the thing to do but it's been done. I usually try to stay below 1200 but before I knew much have towed up longer hills with 1200+ for a while, I now downshift and slowdown. Not just for engine but transmission too.

 

Yes, they can hold those temps but I personally wouldn't push it past 1400°. 

 

Timing plays a huge role in cylinder temp vs manifold temp. A stock 04.5-07 can hit and hold 1450° and never have a cylinder temp issue, but a modified one can be at 1250° and have a much higher cylinder temp. 

 

1250° is my continuous limit with how my motor is tuned. 

Edited November 30, 20186 yr by AH64ID

1 hour ago, Dieselfuture said:

But pistons aren't made out of aluminum, it's some sort of mix of alloys. I heard that our motors were designed to run 1200 continously and plenty of people got it to 1600-1800 for short time. Not saying it's the thing to do but it's been done. I usually try to stay below 1200 but before I knew much have towed up longer hills with 1200+ for a while, I now downshift and slowdown. Not just for engine but transmission too.

I don't like to push beyond 1200. The piston oil cooling jets are what primarily keep the pistons from melting down in much higher EGT's but the piston oil cooling jets have their limits and wide ranging heat cycles like that are increasing the probability of cracking a head.  They are crack prone enough over the long term.  In applications such as this is where compound turbo chargers fill the best of both worlds with a great low end response and a great top end with minimal or no lag as well as keeping EGT's well in check.  They also do a lot to mitigate or almost eliminate black or any smoke for that matter if done right.  

 

What you are seeing as EGT on the exhaust manifold is very likely noticeably lower than what the piston top is actually seeing.  Hence the recommendations to be conservative with respect to the EGT's you generate.  

On ‎11‎/‎29‎/‎2018 at 6:42 AM, Marcus2000monster said:

Well I managed to pull to long steep grades with another 24 valve on a trailer in 6th gear and never pass 1100F! 

 

4.10's are a towing beast but sure do suck empty on the big highway I always figured 4.10's were somewhat hard on overdrive, in manual transmissions, due to the fact they will pull forever in top gear. The 3.55's will force a downshift, a good thing.

On 12/1/2018 at 3:46 AM, NIsaacs said:

 

4.10's are a towing beast but sure do suck empty on the big highway I always figured 4.10's were somewhat hard on overdrive, in manual transmissions, due to the fact they will pull forever in top gear. The 3.55's will force a downshift, a good thing.

I don’t tow very often which is why I’m swapping in a set of 3:54s. I’m MPG and lower RPM hungry lol. I think the lower gear ratio with the 6 speed will be top notch. 

2 hours ago, Marcus2000monster said:

I don’t tow very often which is why I’m swapping in a set of 3:54s. I’m MPG and lower RPM hungry lol. I think the lower gear ratio with the 6 speed will be top notch. 

If your hungry for MPG you might want to consider trying a set of 245/70R 17 tires that are the same overall diameter as 245/75R 16 tires. If you still have the original 16" wheels around and mount some 245/75R 16s, it would give you a boost in MPG for certain along with more towing power too with 3.55s! 30.5 inch tires and 3.55s is a great combination!

1 hour ago, Michaelsloft said:

If your hungry for MPG you might want to consider trying a set of 245/70R 17 tires that are the same overall diameter as 245/75R 16 tires. If you still have the original 16" wheels around and mount some 245/75R 16s, it would give you a boost in MPG for certain along with more towing power too with 3.55s! 30.5 inch tires and 3.55s is a great combination!

I do plan to lower tire size once I have the axles swapped. 

8 minutes ago, Marcus2000monster said:

I do plan to lower tire size once I have the axles swapped. 

Awesome and looking forward to seeing how the axle swap works out for you.

Give you an idea... I'm running 3.69 final to the ground I'm pretty quick now.