Build advise

[freak007]

Hello all, I am looking for some advise for my build... I have been doing alot of searching and alot of reading on several forums (here, Cumminsforum, CompD, DTR, Bombers) and I think I have finally come up with a plan


The truck I am working on is a '92 W250. It has the 21Cm housing and is all stock (for now). I am in the middle of rebuilding the Getrag (seized pocket bearing) and the rear brakes. When the trans is installed it will have a South Bend Con O in front of it.


Next spring this truck will be used for a conversion on my '85 W350 Crew Cab. The Crew is lifted 6" and weighs #6400 pounds with just me and fuel. I am expecting 7000# once I finish the bumpers, add the winch and the CTD conversion. The truck is 80% toy, the rest of the time it is a work truck and tows loads up to 10000#. I expect a "typical" gross weight of 8000 and a max of 20K. I am a flatlander, but I do have relatives in CO and AZ that I like to drive and visit (not likely to tow heavy on these runs).


Now my goals:

1) Must be "idiot proof", I don't want the wife (or anyone else) to accidentally blow it up because it is running on the ragged edge.

2) Must be "clean", I don't mind blotting out the sun at will, but I want to be able to make that choice

3) Must be capable of 16+ MPG (prefer 20+) empty

4) Would like around 300 (sustainable) RWHP


Now the proposed build:

366 spring
BHAF
5x.012 or 5.014 injectors
Super HX40 (toying with 62/65 S300)
4" full exhaust (no stacks)
Denny T cone (switch to stock cone when towing)
PS Intercooler (Coolertubez minimum) - not until swapped
3/8 or 1/2" fuel line - when swapped
Piston lift pump (maybe Airdog)


Does this look like I am on the right track? If anyone has some advise or input it would be appreciated.


PS sorry for the novel

[Richie O]

300 hp is a hot power level. I can tow with mine at 300 but I need to watch it like a hawk. With a 62, 4 inch exhaust, ps cooler, cooler tubes yours will have alot more goodies then mine but I still suspect you could hit 1400 pretty easy while towing. I hit 1600 empty.

[KTA]

That is similar to my trailer puller. Its a 93 W350 Extended cab.
370 marine injector tips on 1st gen bodies
Super 40 16cm
Full 4" exhaust with muffler
Hydroboost brakes
NV4500 Conversion
3.54 gears
Ground stock pin with max travel
Everything else is stock.
It regularly grosses 23000lbs and is rare to ever get driven empty.
Mileage is about 10mpg loaded and about 16mpg empty on highway tread tires, put mud or snow types on and its 15mpg. It is right at 290rwhp and 800ft-lbs.
Oops I forgot at that power level egts can run 1300-1350 which is hotter than some people like, and could spell disaster in the right climate. Denver would probably be a meltdown. Bigger issue is on long hills the radiator can't hack it, and its brand new and the fan all works like it supposed to. The cooling systems on these trucks just can't deal with the heat generated from making that much power on a long term basis. If you aren't going to watch gages sooner or later something bad would happen with this setup.

[freak007]

Richie - Isn't your 300hp machine also running 6x.016s and a smaller turbo? In theory wouldn't my proposed build run much cooler?

KTA - do you think that if I used 5x.012s with the 145* pattern and the coolertubez I would see lower temps and better mileage? Would using the stock pin while towing would bring temps to 1200 or less? How well does your turbo spool with the 370s?


I don't mind paying attention to gauges, but I don't want a rig that needs a baby sitter...

[Richie O]

Richie - Isn't your 300hp machine also running 6x.016s and a smaller turbo? In theory wouldn't my proposed build run much cooler?

You are correct. But that being said my fuel screw has 3 more turns on it. I would suspect a truck with 370's tuned to 300 hp would run about the same temp as a 300 truck with 6x.016's if all else was equal. I would also expect with you having the goodies you listed you would run a lower temp then mine at the same power level. Like I said I max my 1500 isspro out easy. I suspect your mods would still put you on the ragged edge at 300hp. Like KTA says his truck is borderline and he has to keep an eye on it.

[KTA]

[quote="freak007"]
KTA - do you think that if I used 5x.012s with the 145* pattern and the coolertubez I would see lower temps and better mileage? Would using the stock pin while towing would bring temps to 1200 or less? How well does your turbo spool with the 370s?

[quote]

I don't think it would make much diffrence. The stock tubes offer minimal restrictions as they are. Drive slower and you will see better mileage. These trucks are aero horrible but I like driving 70mph. Run 55 instead and you should easily pick up 1-2mpg. Using the stock pin would certainly reduce egt's. If you decrease power by taking away fuel like the pin does that should reduce egts so sure if you reduce power from 300hp to 250hp you should be fine on egt's and coolant temps. My 40 spools like the stock h1c 18cm did.

[unixcowboy]

I'd install a valet switch to kill the afc boost when you didn't want/need the extra fuel - such as when towing.
Since I disconnected the afc boost line I've noticed the truck still runs good and temps and boost are both down.
I'd guess that the 6x.016's are flowing more fuel as a baseline compared to the stock sticks and that's why performance is still acceptable

[oldestof11]

Dont do the CON O, its too small. The "upgrade" 12" is NOT a upgrade. Go with the CON OFE. It will hold your power levels.

[cougar]

Might I suggest one of M&H's fuel pins? Like an M2 or 3. With the star wheel cranked up, the won't add extra fuel until you at a much higher boost pressure.

[JQmile]

I'd add water injection to the list. Worth the EGT drop in my opinion.

[freak007]

Drive slower and you will see better mileage. These trucks are aero horrible but I like driving 70mph. Run 55 instead and you should easily pick up 1-2mpg.

Now that is not an option , But I am glad to hear these are "real world" mileage numbers

Using the stock pin would certainly reduce egt's. If you decrease power by taking away fuel like the pin does that should reduce egts so sure if you reduce power from 300hp to 250hp you should be fine on egt's and coolant temps.

Kinda what I thought... I don't mind the thought of changing the pin when I am going to be towing heavy...

My 40 spools like the stock h1c 18cm did.

Awesome 'cause I have the 21 . Are you satisfied with the Super 40, or do you wish you had used something else? How would a 62/65/12 or 14 S300 compare? What about a 65/71?

Dont do the CON O, its too small. The "upgrade" 12" is NOT a upgrade. Go with the CON OFE. It will hold your power levels.

Too late. I already own the Con O. The Con O is not a 12" clutch, it is a 13" organic (rated at 400hp/800tq) and comes with a new flywheel. I talked to South Bend and based off my goals and useage they suggested either the street dual disk, or the Con O. The individual that I spoke with said I would not have the power to justify the OFE and the OFE's rough engagement can make backing trailers more difficult.

Might I suggest one of M&H's fuel pins? Like an M2 or 3. With the star wheel cranked up, the won't add extra fuel until you at a much higher boost pressure.

Of course you can... Now please point me in the right direction to know who M&H is and what makes their pin a better choice

I'd add water injection to the list. Worth the EGT drop in my opinion.

I would rather run twins... I don't want to worry about the tank running dry in the middle of a pull...

No twins are not in the budget at this time... After I pull the engine for the swap and it gets studded then it is a potential upgrade...

[KTA]

For the under 400engine hp crowd I have always liked the Super 40 (Not the regular HX40) over any of the s300 variants. It was specificly designed for a hot rod 5.9L and as such I think it best matches the engines characteristics. 40's have gotten a bad rap from people abusing them and throwing 500hp worth of fuel at them. They are not as beefy as an s300 so they can't handle the abuse. Use them properly and they are as reliable as the engine they are attached to.

[921stgen]

Alwaysworking is making these fuel pins you can also PM him on the other 1stgen forums. http://cgi.ebay.com/ebaymotors/88-93-do ... ccessories
Member Denny T makes these fuel pins.
http://www.dennytperformance.com/products.htm
Like anything else its a matter of opinion who's is better but the M&H pins come in a wide veriety of power levels.

[RSWORDS]

If you hit up Always Working (in the M&H section) over on dieselbombers.com they pins are only $105 shipped. He is a sponcor over there and does not have to pay the Ebay Fees...

[freak007]

Well... I just got a great deal on a set of 5x.014s... For the price I paid I could swap out the nozzles and still have gotten a good deal... I would rather not spend the money if I don't have to though


So with that in mind, what is going to have a better chance of keeping me cool, and being upgradeable to twins in the future - a Super 40, or a S300 variant?