Swapping out injectors to tow?

N

nate

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I have a trip to Alaska coming up and the truck is going to be loaded down fairly heavy.

Right now truck is setup with Mach 4s and a 62/12 turbo. I have a TST Comp and Smarty as well.

I towed a trailer yesterday, about 6k, and found I can hit 1200* without getting on it very hard. Cruising it sits at around 950*

Is this something I have to deal with if I don't have twins or a very large single turbo? Based on another thread I had, 62/12 seemed to be a good combo for setup.

I was thinking maybe it would be better to swap in my RV275 injectors and not have to worry too much about temps... probably get better mileage too?
 
Why not turn off the TST instead, w/ those injectors and smarty you should have plenty of power, w/ less EGT
 
TST was turned off actually. Smarty was all the way up though. I wanted to turn it off as well but I didn't have time.
 
Put in the RV275s. The Mach 4s are poor injectors for towing heavy. I leave mine in for towing around here, and just drop a gear or back out of it to keep it cool. There is no way I would take off cross country towing heavy with a set of Mach 4s.
 
Maybe for auto, but I pulled three loads of alfalfa back from Maryville, MO two years ago with my 4's and a 62/14. Grossed 42k with the last load (wet hay). This was a stick though.
 
My buddies truck has mach4's and sps62-14 w/ an edge/attitude setup and the egt's are very controllable. We had my ford which is 8k by itself and a big gooseneck tandem dual trailer that was about 7k so it grossed about 22.5k and it did great towing.
I was very impressed with how it did for a smaller single turbo. Even when not towing and the edge is cranked up the turbo will clean up all of the smoke at 32lbs and keep the egt's low. maybe the edge isnt a really strong box but the truck has a new vp and fass so its not fuel starved.
 
Ever tried the half power setting on the Smarty? Might be worth giving a shot, a lot easier than swapping injectors.
 
I just put some 4's and have used 4 other injectors and these have lower EGT's even than some 75's in other brands.Don definately has something going there! Use only the smarty in the fuel mileage #1 setting and go to the timing setting and set it to advanced. It will then add no more fuel but you will have the just advanced setting instead of the extreme setting that usually defaults to in that setting from what I am seeing.You do need that little bit of advance with those sticks in my opinion.$.02
 
Lower EGTs that 75hp injectors??? Those must have been some pretty sorry injectors. There is no way these Mach 4s will run as cool as any of the 80horse injectors I have run.
 
What boost levels? Have you checked for leaks? Checked the wastegate on the turbo?

Water Injection....Water injection....

Mach 4's are slightly too big injector for that turbo. I would keep the current setup before going to twins but add some water injection.
 
SmokinCummins said:
Lower EGTs that 75hp injectors??? Those must have been some pretty sorry injectors. There is no way these Mach 4s will run as cool as any of the 80horse injectors I have run.
Click to expand...

Fact not fiction! I would not bash any brands but ALL were name brands and new out of the box and they all smoked more. Now when they were cranked up with a Comp Hot they were just as warm.
 
I'm going to mess around with the Smarty and see what that does. I am looking for the best fuel mileage and drivability on this ~3800 mile trip.

I talked to HTT yesterday and they seems to think The 62/12 is the correct turbo. They said the 63/71/13 would run hotter because of the larger turbine wheel and so would a 62/14.

A 64/12 would work, but they are saying the 62/12 outflows the stock intercooler, so without an intercooler upgrade, I wouldn't see much from the 64mm compressor.

I have a bonus coming to me in the next month, may use some of that money for a twin setup/upgraded intercooler.
 
SmokinCummins said:
Lower EGTs that 75hp injectors??? Those must have been some pretty sorry injectors. There is no way these Mach 4s will run as cool as any of the 80horse injectors I have run.
Click to expand...

have you ran 4's?

he not the first person to say that 4's run cooler than 75hp stixs.

4's ran cooler than 100's and 125's in my truck.
 
I run mach 4's with a SPS 62/14. No egt issues. Just turn down the box a little and keep the rpms up. I tow EVERYWHERE with mine!
 
bsmith said:
have you ran 4's?

he not the first person to say that 4's run cooler than 75hp stixs.

4's ran cooler than 100's and 125's in my truck.
Click to expand...

Yes I have ran 4s - and many many others out there. I have tried about 30 different sets of injectors now ranging from stock to the ones I made 640 horsepower on. I am not new to modding a Cummins. I have also towed all across the USA and know what different injectors do with different loads at different temps and altitudes. I can keep the mach 4s cool, but there is no way you will run with the air on and the cruise set on 80 and maintain a safe constant EGT. FWIW, I never tow with a fueling box on either.

Yes, I can keep them cool by keeping the rpms up, but when you are traveling long distances - dropping a gear to keep it cool is a very expensive option. Have you ever burned over $1000 per week in diesel fuel? You learn real fast how to get better mileage when fuel is a major expense. Dropping a gear to keep rpms up is not an option. He asked about a trip to Alaska, not a trip across town.
 
this is some good info on here. I would like to stepup to mach 4's one day and i have close to the same setup so keep the info coming
 
I have large-ish sticks, a fat housing on a 62 and have no problems towing. I cut the fuel box off and use my foot carefully
 
It's not that I'm running 1300*, though I can hit that without trying too hard.

Of course I'm testing the truck here in Idaho were it's been in the 90s. It'll probably be in the single digits at best on the ALCAN.

When I had my RV275 injectors, Smarty on 9 and TST 1 (60hp box) on, It towed very nice. It'd stay around 900* and a few of the steeper grades in the Rockies I'd have to drop down to 3rd gear to keep it under 1250*.
 
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