06 SMB 6.0 4x4 Bulletproofing Anyone? - Page 9

ndubes · 06-06-2018, 05:31 PM

First real big test for the engine this weekend. Towing a 25ft trailer from phoenix up to flagstaff for the Made in the Shade Beer Festival

. I'll program the 65hp tow tune through the SCT before we head out, and probably keep it to 70mph tops (lower on the grades) to be safe. I also got a pyrometer and boost gauge installed this week so I'll be able to keep an eye on that info as well. Hopefully all goes well!

WhitH · 06-06-2018, 06:19 PM

Nice! Be interested to see how it goes and what your temps are. Any idea how much the trailer weighs?

ndubes · 06-06-2018, 10:31 PM

Quote:

Originally Posted by WhitH

Nice! Be interested to see how it goes and what your temps are. Any idea how much the trailer weighs?

Trailer is only about 5k lbs, so its not terribly heavy but the climb from Phoenix to Flagstaff is a pretty steep one so it will certainly be working. I'll make note of all the temps, never monitored boost or EGT so i'll be curious to see how high those go. The Pyrometer was installed in the exhaust manifold, I didn't do that one myself (too scared

), but the mechanic said that's where he always does it so we will see what readings I get. stay tuned!

ndubes · 06-08-2018, 06:19 PM

Alrighty we made it up to flagstaff! For the most part the van did well. We took it easy ~50mph on the steep climbs, no more than 65-70 on flats or downhill. It was 108 in Phoenix, 85 in flagstaff so it was plenty hot outside. Used the 65hp towing SCT tune, and turned off overdrive on the climbs.

Pyrometer stayed pretty steady around 900, peaked around 1100.

EOT/WT/TRAN readings:
228/222/190 cruising flat ground ~65mph
236/229/202 on gradual climb ~65mph
248/240/209 on the steepest climb ~45-50mph
At those peak temperatures the “idiot gauge” factory water temp gauge started to climb and I would let off quite a bit until it started going down. That’s the one time we really felt a little worried. I can’t imagine towing more than the 5,000lb we towed if climbing like that though.

Temps would cool down pretty fast to the 220/215/195 range when we would get to the top of a hill and start going downhill.

One very annoying thing that happened is the AC stopped blowing out of the vents halfway here, only blew out of the floor and out of the back it would only blow heat. I’m wondering if overspray from the contact adhesive used for the quietride insulation kit (which made a noticeable difference btw, there’s another thread I posted to about that) somehow affected some of the flappers. I will probably have to take it in to mechanic when we get home, it’ll be a hot ride back. We did turn off the AC on the climbs.

Anyone have thoughts on those temps? At this stage there’s nothing additional I could do to bulletproof the rig I think...

Bbasso · 06-09-2018, 01:31 AM

70mph towing? ?? Where's the fire?
I've towed many things but yet to go past 65mph, I just don't see the need for speed when on the road...
I'd bet all the numbers across the board would drop if you backed off the go pedal.

But enough of my rant, Temps look ok for your rig and conditions. You're simply using your rig and it generates heat...

freeagent · 06-09-2018, 09:00 AM

On your A/C problem are you sure the air is only blowing out at the floor? Is any air blowing out of the defrost vents? Does any air come out of the dash vents when idling?

ndubes · 06-09-2018, 10:58 AM

Quote:

Originally Posted by freeagent

On your A/C problem are you sure the air is only blowing out at the floor? Is any air blowing out of the defrost vents? Does any air come out of the dash vents when idling?

It’s the same at idle, everything out of the floor nothing out of the defrost or dash vents... very strange. On the way up it started that as we left but eventually they turned on. Then after we stopped for a bite it wouldn’t turn back on the dash vents. Very strange.

70mph was only on the downhills. Didn’t go past 60-65ish on the flats and 50-55ish on the climbs. Tried to kinda keep my foot in tune with the engine temps.

Bbasso · 06-09-2018, 06:17 PM

Quote:

Originally Posted by ndubes

One very annoying thing that happened is the AC stopped blowing out of the vents halfway here, only blew out of the floor and out of the back it would only blow heat.

Sounds like the typical vacuum leak, most of the time it's a small hose on the passenger side near the blower motor and or into the cockpit.
You might have to run a new hose, takes time and a PIA but simple.