Driving Impressions after ATS turbo install

[reklund]

Hey guys! I finally hooked the trailer up and went down south to do some rockcrawling. Thought I'd post up some driving impressions, as this was my first trip out with the trailer and my crawler since I installed my used ATS turbo kit and MBRP 4" exhaust. (for reference, my pyro is installed in the drivers side exhaust manifold, below the brake booster)

-The truck drives like a dream! Now she'll hold 70 mph all day with no problem. Cruises at 70 on flat ground with the EGT's at about 700 and about 3psi boost.

-On the hills, with the cruise set, it no longer drops off speed as you climb the hill. The biggest hill between here and Socorro (only about 100 miles south of my house in Albuquerque) I cruised up at 65, but let off it because the EGT's approached 1100 at about 8psi boost. Exactly how long can one run close to the 1250 *F mark before things start to melt? On a non-wastegated turbo, is that all the boost I'll get? I didn't want to find out, so I let off at 1100, about 3/4 way up the hill.

-The MBRP 4" exhaust makes more noise than the stock exhaust for sure, and I've still got that pesky exhaust leak coming from somewhere near the passenger footwell. I'll put the truck on the lift at work this week and see where the soot is... I've gotta keep the radio up a little louder than before to drown out the exhaust noise- might look into some Dynamat to deaden some of that sound.

-Fuel mileage at 70 was the same as without the turbo at 60-65. Right at 16 mpg- not too shabby for an old truck!

-Had 2 trailer tires blister pretty badly on the way down. Put the spare on the worst one and hoped for the best with the other. Made it home without incident, but must replace all 5 trailer tires. Shoulda done it when I bought the trailer last fall, but didn't.

-Overall, I'm very pleased with the entire setup. If I can fix the exhaust leak, get the front end to sit level, and find some 95-98 PSD alloy wheels for it, I'll be set

Ryan
(Oh, and my crawler performed flawlessly too! I LOVE the beadlocked 37" tires...but think I might upgrade to some 42" tread next season...)

 

[JPR]

Gotta love that first trip after a turbo.

Regarding the exhaust leak, I used the stainless steel band type clamps with the new exhaust. They are much nicer than the regular u-bolt style.

 

[reklund]

Thanks, but the exhaust leak isn't where I could use a band clamp. I believe that it is either where the cast iron up-pipe bolts to the passenger side manifold, or where the up-pipe or downpipe slip into the turbocharger housing. (On my older ATS kit, its just a slip-fit into the housing- no fasteners of any kind)

I may end up removing the up and down pipes and coating them with some muffler putty or something similar. I just can't stand the sound of the exhaust leak- it's making me CRAZY!

Ryan

 

[rubberfish]

Exactly how long can one run close to the 1250 *F mark before things start to melt? I didn't want to find out, so I let off at 1100, about 3/4 way up the hill.

At 1250* you can run there all day long if you wanted/had too.
Sounds like you had a good trip.

 

[reklund]

really? I thought thats where things melted down in these things...

 

[The Warden]

1250° is the breaking point. It's technically safe to stay at that temperature indefinitely, but certainly, you shouldn't allow the exhaust to get any hotter than that.

Personally, I'd rather err on the side of caution on this one, so I wouldn't let the temperature stay above 1100° or so for any real length of time, to account for a possibly inaccurate gauge and to not work the engine too horribly hard. But, that's just me

 

[reklund]

Agreed. I'd really hate to mess something up when its so avoidable. Its not a big deal to ease up on the go pedal and keep things safe, at least for me.

Ryan

 

[Agnem]

1220.6 F is the melting temperature of aluminum (pistons). The reason you can go past that is because there is oil squirting on the back of the piston, and this is causing heat transfer, much the way a fire in a steam engine is hot enough to melt the boiler, but because of the water, the heat is carried away and the steel doesn't melt. However, you need to ask yourself two questions.

1) - Does the oil completely cover the bottom of the piston uniformly, and is it refreshed fast enough to effect proper heat transfer.

2) - Is your pyrometer completely accurate at 1250 degrees?

I think the answer to both is no, so those who choose engine life over power, will back out at 1100.

 

[pafixitman]

Ryan,
You may not have a leak. I know my interior noise in the pass footwell is much louder than before. Some Dynamat under the carpet and all should be good.

 

[budtoh3zo]

its just amazing what turbos can do for these girls.

 

[reklund]

Ryan,
You may not have a leak. I know my interior noise in the pass footwell is much louder than before. Some Dynamat under the carpet and all should be good.

I put the truck on the rack at work today, and discovered a very small leak where the crossover pipe mates to the passenger side manifold. It looks like if I remove it, whack it with a hammer a little and then smear some antisieze in there it'll seal up. Even then I'm sure there will be more noise than usual.

You may be onto something about the interior noise though... I've already plotted a plan to swipe some dynamat from the supply my Dad's got stashed for his Porsche projects...

On another note, I discovered that at least 3 of my trailer tires are shot. I replaced one with the spare this weekend to go 'wheelin, but the others are still de-laminating and out of round. I ended up buying 5 new Maxxis Trailer tires today and mounted them up. When mounting the tires, I found out that one of my trailer wheels was an oddball- it was an inch wider than the rest. I used it as the spare this time, and put the 4 matching wheels on the trailer. I actually took the time to balance the trailer tires, which is probably overkill, but I think the smoother, the better.

Oh, and Mel, I agree about the longevity-vs-power argument. I'll let up at 1100...

Ryan