Will a GTP38R lower my towing EGTs?

[Ferdy Mint]

I tow DOT with an E99 F550 that we upgraded to L99 with turbo, manifold, pedestal and Riffraff stuff like bellows up pipes and their plenums. EGPV is gone and it's 4" all the way back to side dump behind the cab, no muffler just a fake converter welded on the outside of the straight pipe in case of DOT inspection. I got 130% injectors from FullForce with their stock tunes on the E99 XEV1. I tow on their Heavy Tow tune, position 1 on the Hydra. I tuned this truck with towing in mind. My trailers are 21k or 26k lbs, loaded.

I have a problem with EGTs climbing over 1250F on hills so I have to back off the throttle. CAI from S&B helped a little. I know the old PCM and crappy FF stock tunes are part of my problems and plan to install a NVK4 that I have on the shelf, with Gearhead heavy tow tunes. When I get a week off work...someday... I bet we have an asset in the forum who can also tune an XEV1 just fine but I also hear that the NVK4 shifts the 4R100 and works the cruise better (I have NVK4/Gearhead/Rosewoods on my 2000 F250)

My master tech buddy rebuilt, bored and ARP studded the 7.3 so it should be good. Alas we found PM rods in there, so somebody had swapped in a newer block. The PO died suddenly so nobody to ask about that. I like to stay under 3100 rpm so figure the PM rods will not be a problem.

I believe that I've done all I can to reduce EGTs on a stock L99 turbo and am considering the GTP38R. The used stock turbo we put in there turns out to be leaking oil into intercooler anyway. More air on the same fuel amount should lower EGTs. What do you think?

In the past I would post this on FTE but they got bought by a huge corporation and have become woke jerks so I left, after 21 years of contributing there. They banned my IDI expert buddy LoneWolf and that straw broke the camel's back.

 

[aggiediesel01]

That's a pricey unit. It's got a big following over the years but have you checked with KC Turbos to see their other more recent stuff as well? I'd give them a call or email with the info you've got above and see what they might recommend. I recently upgraded my stock unit to a smaller A/R turbine housing and their S300X rotating assembly and it is impressive, especially for less then the cost of a rebuilt unit. I don't tow a heavy load very often so I can't comment on EGTs with loads but those wheels move a lot of air now. I can easily hit 30psi with my Gearhead tunes Hydra #4 and short term egts are barely at 1000. Being that yours is a F550, I would have them take into account your normal RPMs at highway speeds too. If you're running 2500 or higher at highway speed your setup may not be suited to a tighter A/R on the exhaust. But those guys are pretty smart, I'd let them suggest something for you and I bet they can show you the comparison to the 38R to see which is a better fit for you. I've been happy with my experience with KC and also with Gearhead, I'd get them to send you some new files to try in the computer you've got unless they say the NVK4 is a better starting point.

 

[Ferdy Mint]

I think I saw KC Turbos out on FTE last year, and the KC guy answered guys' questions right in the forum, iirc. Are they in this forum too? I found their website and their 7.3 tow pack (only $2900) which is a lot like I setup my truck, except for the turbo. Interesting... I don't go fast with this truck due to the low gearing, 4.88. I'll see 3000 climbing the evil hill out of the quarry, but cruise at more like 22-2300.

$1150 is a fair price for their KC300x, indeed. The lowest I've found a GTP38R for is about $1700.

 

[Ferdy Mint]

I looked into the KC300x turbos a bit. It sure looks like a much better deal than the 38R. Also, KC will rebuild your turbo if needed, and offers a warranty. Garret otoh is a huge corporation, and we all know what that means for customer service.

Thanks for putting me on the right path.

 

[Oledirtypearl86]

IV used just bigger housings and wheels to make a little more boost to push egts down but yes mpre air same fuel lowers egts.

 

[Ferdy Mint]

OK guys, I just pulled the trigger on a KC300x Stage 2 Turbo (63/73) .84 and I'm looking forward to getting that puppy installed. KC had send me a discount code POWERSTOKED but it didn't work when I ordered.

My OE turbo in the 550 is guzzling a quart of oil a week now. Time to junk it.

 

[dsrace]

i know this is an older post, but, how did that work out for you?

i am swapping down to a sxe 363/68 with a .91 from my current sxe366/73 with .91. i pull a toyhauler 10500 lbs loaded and never exceed 2400 rpms while towing and dip to 1800 at 65 mph. the sxe 366/73 efficency range is 1950/ 2000 rpm and up. i know at 75 mph, 3.73 gears, towing my toyhauler at 12'6" tall, i hit a brick wall at 1200* egts climbing hills in the wind. anything above 2k rpm the turbo response is right now. i am running 205/30 inj's but even on 180/30's you should see 40 psi peak with those and enough flow that there "shouldn't" be egt issues. everyone i know with the 38r, have egt issues....... when i comes to pulling a camper.