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I just made the trip back to florida, got my transmission fixed 2 days before i left new mexico. All the way home my truck would only run 70 mph. That is 2200 rpm. My truck runs super good, egt is no more than 900. no smoke at any speed. Accelerates good and good power, but tops out at 70. I have 9 psi under full power in 4th gear. 5 psi running 70 in 5th. the transmission guy put a BB in the wastegate line and blocked it off. that increased my psi. My truck also ran 70 mph when it was NA, I am surprised to only see 70 with the turbo.
Since I turned the fuel back 6 flats to get the egt down, maybe i backed it off a little too much. The truck ran flawless for 1800 miles in three days, but I had hell trying to keep up with my wife in the navigator and she was pulling a 12 ft. covered trailer fairly loaded.
I believe the navigator would pull the trailer 100 mph, because she hit over 80 several times passing.
Maybe I'm expecting too much, but I was really counting on going at least 75.
What gear ratio do you have maybe your tach is off. That wouldn't be right you should be able to hit 75 with 4.11's and no overdrive.
It does take fuel to make boost though, but something doesn,t smell right if the truck wouldn't top out before the turbo. What kind of truck are we talking about.
You can run more fuel with the turbo than with an na engine the turbo supplies more air lowering the egt's.
Thanks Star, thats what I thought too, but when I installed the turbo, I turned it up two flats and when I loaded the truck it jumped straight to 1250 egt. I had to drive all the way out west watching that guage. I finally turned the pump back 6 flats and got the egt to no more than 1050.
Then the transmission guy blocked off the wastegate and the pressure increased by about 2 over the whole range and the egt dropped by about 100.
I suspect you may be right, I think I will start 1 flat at a time, because I would like to hold the egt to no more than 1050. I bet I could use a little more fuel.
I'm planning to haul a truck load of machine tools, and tow my hot rod to new mexico in mid february. I will be loaded, so I need to tune this sucker up, before then. The engine has maybe 25 or 30k since rebuild and it only used a half quart of oil in the 1800 miles.
The motor should turn over 3 grand turbo or not. if 22 is the most it will turn something is not right you should be able to turn 80 without 5th gear.
This is not an ex uhaul or fleet truck of some kind.
I think the govenor is set at 3300. I have seen 3200 in first, second and third, will do about 2800 in 4th, and 2200 in 5th. that is all on level ground. I will turn the fuel up some, but i don't want high egt levels.
on the trip home i would run it up to about 63-65 mph in 4th, just to get up to speed faster. At 2200 rpm in 4th, I'm doing 55mph.
empty the truck is 8700 lbs, yes its heavy, as in the picture the bed sticks out about 9 inches on each side. the top of the bed does not go far above the cab.
yes it does catch the wind. Wind drag could be a big factor.
I never expected to go 80 or 90. I just thought the turbo would give me an extra 5 mph.
As a NA I used to down shift on any kind of hill, I no longer have to do that. I have better acceleration and definately more HP.
I will work on the fuel thing. I'm getting a knee replacement this comming tuesday, so I will be hobbling around for a while.
are you saying that on the floor board your truck wont do over 70? somethings wrong then, mine would burry the speedo in 3rd but i tach 1100+ rpm more than you, when i had the gps in my truck i saw some pretty high speed numbers, i would think your truck would go faster than that, heck mines still n/a