Building a TOW based truck

[12vsuburban]

good day Gents(and ladies),
I've done lots of reading on what others have been doing to upping power but have a few questions. I hve two projects in the works, but both will be similar form a function standpoint, just one being much more custom(conversion). Both trucks are 1992 based intercooled H1C turbo'd Autos, 2wd. Both will be built to have good power, but mainly interested in assloads of torque and and good as MILAGE as I can get and still be able to pull a 10-12k lb trailer without running out of power. Main reason for this is pulling our race car from Houston to Wednover, UT for racing at the Bonneville Salt Flats. So a big heavy box on the hwy at 80mph needs some power.
The d350 has been turned up just a bit, but no fuel pin yet, I wont do much more than adjusting the pump, maybe a fuel pin and upgrades to the factory turbo. It has 4" open exh now. It has OK power, just laggy with the big Exh turbine housing.

Peoject #2, which is where most of my questions come in is a conversion. I have a 1969 Chevy suburban, sitting on a '78 Chevy 3/4 ton 4wd chassis. I have a 1993 3500HD Chevy for parts and thinking of running the suburban as 2wd, utilizing the front leafs with the large I-bean axle form the 3500HD with 19.5 wheels(5/10 lug) as well as the Dana 70HD (10bolt 19.5 wheels). THis axle has 3.73 gears in it now, which are a bit higher than the 3.55 in the other trucks, but can run a taller tire. the 3.73s should give about 2100rpm at 80mph or so...any thoughts here?? As well the 70HD , I believe, uses Dana 80 carrier bearings, but std Dana70 gears, so a gear swap should be possible to 3.55 if needed)

I would love to have 7-800ft-lb and what ever HP comes with that...more is great, but as stated, dont want to kill my fuel milage and have to worry about EGTs.
-Injectors, not sure if I need them...I hear the Bosch 190s are a decent upgrade and effiecient for towing
-Turbo: thinking of just uprading the existing H1c. I read different schools of thought on turbos for towing, but I want decent off idle spool but not have to run water injection full time if I have a trailer behind me...I am not opposed to water injection, in fact it will likely be installed. could be nice when towing up those long hills in the mountians.
-Fuel pin: something in the mid range like a stage 2 or 3
Intercooler: The burb should be able to fit a Power Stroke intercooler to replace the original one form the 1st gen donor.
Trans: Autos are nice, but the non-lockup bothers me. A after market converter is like halfway to a NV4500 conersion or so...I plan to run the d350 with its stock auto and see how I like it, that should help me decide on just using the auto or stepping up to a NV. I can put an additional heavy duty cooler with fan to help cool the auto if used.

Any suggestions or oppinions greatly appreciated. Other than the once a year trip to the salt, it will be carrying normal loads, pulling an old car behind it or something like that. I just want to build it once, build it right and be able to pull our trailer and not have to get depressed when I see a hill coming up.....

Thanks, Hans

[BILTIT]

7-800ft-lbs of torque is not usable for towing with only an upgraded H1C, IMO. The turbo is always the limiting factor when turning up power AND wanting to tow. I would recommend a bigger turbo if wanting that much power and comfortable towing or you have to limit the amount of fuel by EGT's when towing.

I run a he351cw (off an 06 dodge) turbo and have my pump turned up a turn or maybe two, stock injectors and i can hit 1250 uphill with a 10k-lb 28ft fifth wheel camper behind me. I limited my full power screw to keep the egt's in check. The 351cw is as good or better than an upgraded H1C.

[cmann250]

Being intercooled and automatic, I bet you have a 21cm exhaust housing which is the most laggy of all the CTD/Dodge turbos. If my memory serves me correctly, a compressor upgrade is about $300 and a smaller exhaust housing is $200. A whole new turbo may suit your wants/needs better.

Keep in mind that 7-800 lb-ft of torque will be 3-400 hp with these trucks.

[ellis93]

With mods in my sig,I gross 11k and change for truck and trailer,loaded I've touched around 22k. With just the truck and trailer,if I'm ugly to it,I cant get the egts over 1000. Loaded it'll hit 1250/1300 in short order if you lug the truck in higher gears,keep the RPMs up and its very controllable.

Caleb is right the hybrid turbo route is higher than say a knock off China hx40 that will grenade into your motor,I went this route for simplicity. No screwing with waste gates to open/close vanes, didn't have to chop up my down pipe, no cobbled oil pressure/return lines,and I didn't have to buy an adapter for anything.
I believe it works well for me,well enough that I'm not looking for another ....yet .....always the need for more power sometime.

[cmann250]

Something else to consider is how do you know you want that much torque? It sounds like a fun number for sure, but I have alot less and I'm pretty happy about how my truck tows. I have an HX35, a 2nd gen intercooler, a pretty turned up pump, and a stock auto. The smaller exhaust housing on the HX35 has made the biggest difference when towing for me. I had a 4x4 F-250 on a single tandem goose neck and was really pleased about how it acted. It's all in what you're used to. Comparing torque, the 2500HD 6.0L Chevy farm truck is a DOG compared to my Dodge.

As far as injectors, your 6x.009" stock intercooled injectors don't offer a whole lot of room for growth.

[12vsuburban]

Yeah, the 700-800 is reàlly a guesstimate. I definetely dont need 3-400hp, more like 250-300hp. I dont need a big number to brag about , just dont want it slowing down on hills...maybe 6-700ftlb would do it, especially if i use the 3.73s.
Ellis, your setup seems really close to what I was thinking. What kind of injectors are 7x10? Was also thinking some 6x12 would work nicely.
Ive heard good and bad about both the HX35 and he351, mainly thoughts on the smeller exh housings causing High egts when towing. Dollar for dollar it seems spending the money on upgrading my original is a good deal, thatvgetting into a "perfect" turbo for my application gets into the $1000+ range. I know Im probably thinking overkill being that it will only be loaded to the hilt once a year, but driving 25hrs one way in an underpowered or High egt truck is stressfull, then trying to drive a car across the desert at 275-300mph the next morning...
Caleb, do you not Even have a converter in your auto? Spending 500-800 on a converter seems crazy to me and still it has no lockup....

[ellis93]

Got them from JKidd on here,diesel auto power/DAP,they work well. I've hauled some nasty chit,not for a solid day but a few hundred miles,mostly in state. Tractors,junk iron,green oak logs etc.

The thing about my truck is the gears,4:11,they don't work that motor till fourth gear.

I went thru the exhaust housing thing with mine,had the stock 18,then went to an hx35 with a 12cm housing. I liked it but thought it kept temps up a touch,bought another turbo with a 14 on it and havent looked back.

FWIW.... This piece together turbo will puke out 40plus psi and still keep my junk cool....but I can't use all of that for the thought of pushing out my head gasket.

[cmann250]

Caleb, do you not Even have a converter in your auto? Spending 500-800 on a converter seems crazy to me and still it has no lockup....

Everything is stock. I've bumped line pressure and set shift points so be a little more sporty. I have a Suncoast converter waiting to be installed, I just don't have the time. I bought that used converter and got a deal on it. I had a 47RH for a while, but I broke it. Building them to hold 300 hp and standing up to responsible driving isn't too costly. Just another option. I wheel and deal alot Some would call me a gambler too.

I have the same fears about the HE351, but evidently they are unfounded. I'd think a 9cm housing would cause drive pressure and EGT issuses, but that is evidently not the case. I suspect I'm between 250 and 300hp. I also have 3.07 gears since Chrysler stuck me with the non-O/D 727.

[Tacoclaw]

Personally, I would put a 7.3 intercooler, BHAF or similar filter setup, an upgraded intake horn, an HE351 with a ported 'gate, and a port/polish on a new Cummins head. A LPLP, upgraded inlet lines and no bigger than 5x12 injectors.

With a stick I see that setup spooling extremely quick, still able to dump drive if you need to rev it out, and probably able to run right up to the limits of the cooling system and still stay cool.

The new head may seem a bit ridiculous, but it's only ~$700 ($xxx(x) for porting)for a loaded Cummins head and no matter how good everything else flows its still got to stuff it all down those little, crappy ports.

[oldestof11]

Since you have an auto, it might be cheaper to find an hx40 with a 16cm housing. The he351 has more flower through the exhaust housing because of the undivided housing, larger wastegate, and 4"outlet. Had the 60cm super 40 wheel on it.

[revemup15]

If you like to blow hg often get a he351... if it were me i would do the 60mm upgrade for the h1c.. i feel they support same power as the he351

[BILTIT]

What do you call "often" with a 351?

[Tacoclaw]

I would also probably install a coolant bypass to help with cooling the rear of the head. My back three cylinders had slight scuffing in the bores and the fellow I had do my head told me it was probably ran hot and the pistons swelled a bit. Since cooling and airflow isn't optimal to the rear cylinders this made pretty good sense to me.

[BILTIT]

Personally, I would put a 7.3 intercooler, BHAF or similar filter setup, an upgraded intake horn, an HE351 with a ported 'gate, and a port/polish on a new Cummins head. A LPLP, upgraded inlet lines and no bigger than 5x12 injectors.

With a stick I see that setup spooling extremely quick, still able to dump drive if you need to rev it out, and probably able to run right up to the limits of the cooling system and still stay cool.

The new head may seem a bit ridiculous, but it's only ~$700 ($xxx(x) for porting)for a loaded Cummins head and no matter how good everything else flows its still got to stuff it all down those little, crappy ports.

Where is the best place to find a loaded/ported head?

[Tacoclaw]

I ordered mine through a local performance shop and just had him let his machinist do the porting while he had it apart for O-ringing and valve springs. You can buy the Chinese heads for a little cheaper, and they're supposedly just as good as any other, but I just went ahead and sprung for the Cummins head.