'Bulletproofing' an IDI?

[Andertusa]

I have a 1984 F350 RC-DRW with a 4-speed and the Sterling. I want to build it for towing and power, but as I'm often very 'gorilla-ish' in my driving, the truck needs to be build as 'failureproof' as possible. What can and or should be done to make the old mule solid as a rock?

 

[88 Ford]

When you say more power, what is your end goal? Knowing that will help us answer the question a little better.

 

[Andertusa]

Aiming near say 200-215HP and maybe around 450tq if possible, but the real truth is I would sacrifice power for mileage and durability, but only to a point.

 

[Andertusa]

I've thought of adding a main girdle to reinforce the bottom, but what can be done to prevent head cracking and destroying head gaskets, other than keeping the boost and EGT's down?

 

[towcat]

for starters, these motors were built with the vocational driver/gorilla in mind. you need to be honest with yourself what loads are you going to be pulling and how fast do you want to go. two critical questions. bottom line....these trucks have their limitations. if you respect the limitations they will reward you with years of heavy service. if you expect the truck to keep up with a new truck, you better start budgeting for a new one now.

 

[Andertusa]

I've been thinking that 60-65 is fast enough, and I'm thinking of pulling a gooseneck pulling up-to around 15-18,000lbs with it. One of my plans is to maybe do a trans swap to a newer 5 or six speed overdrive unit too.

 

[towcat]

I've been thinking that 60-65 is fast enough, and I'm thinking of pulling a gooseneck pulling up-to around 15-18,000lbs with it. One of my plans is to maybe do a trans swap to a newer 5 or six speed overdrive unit too.

with the above response, here's my suggestion......
pull the 6.9 refresh the gaskets and add ARP studs.
install ATS 093 aftermarket turbo kit and add intercooler.
add pyro and boost gauges. put them in a place where it take no effort to scan them easily.
add a ZF5 trans. anything more is a waster of money. you gain no extra gears for overdrive.
add desired pump and injectors.
re-gear your rear to 5.13
add hydroboost system.
that's my suggestion. others certainly will vary.

 

[Andertusa]

Well thank you guys for your input, but why the 5.13 ratio over like a 3.55? I mean I know the extra weight will need extra 'umph' but that seems awfully high( or low, I can't remember the term).

 

[towcat]

Well thank you guys for your input, but why the 5.13 ratio over like a 3.55? I mean I know the extra weight will need extra 'umph' but that seems awfully high( or low, I can't remember the term).

3.55 is a fuel economy gearset. 5.13 is for heavy towing which your intention is for. like I originally said........CHOOSE ONE.

 

[IDIoit]

knowing what i have experienced/know now, the very very first thing i will do to any IDI, is pop the heads off and install new gaskets and studs.
reseal everything.
i have put a fair amount of work into my truck, to only pop a head gasket.
fun fun!!!

the heaviest ive towed was 4 tons.
i had zero issues with it, i normally tow around 3-4000 lbs.
the truck does great with 3.55's
i wont change them because my truck is intended for hauling the family around.

you must ask yourself how much do you tow.

to me 4 tons is alot of weight. to towcat and others that get down and dirty with towing, 4 tons isnt much.

with my choice of IP and injectors my ass dyno puts me well over the 215 hp range.

this is with a 94 7.3T, 105 cc pump, good injectors, 093 ATS with a FMIC

i have a rebuilt turbo, and a cam i have yet to install.


the real question is......

HOW MUCH DOUGH DO YOU WANT TO SPEND TO GO?

 

[icanfixall]

ARP studs will keep the head gaskets in place better than stock bolts. As for the bottom end needing a stud girdle.. nope.. Its never been needed or required yet. Change the rockers to the 7.3 type. the 6.9 rockers were problematic. Aso install a typ4 cam and a Moose pump. You will have all the power you need. I run a set of 3.55 gears and tow heavy. I plan changing them to 3.73. I do fine with the 3.55 but my take off is sluggish.

 

[BDCarrillo]

Harland sharpe roller rockers!!

 

[burt]

There is a big difference between towing 4 ton and 18000 lb. Terrain is a big consideration. 18000 with 3.55 gears will require very flat terrain to even work. With 4.10 gears that load would require me to put it in 4low for some of the hills in northern ca. If your rig is a 2 wheel drive you will have to re gear if you expect to pull 18000lb. I'm re gearing to 5.13 myself from 4.10. I have a 7.3t with a sidewinder and moose pump. No studs but wastegated at 10psi. I think brakes are ok if you drive accordingly. Depending on budget I would say gauges first then low gears. It will be painfully slow so zf 5 and or a gearvendors. Ujoint up grade or at least making sure they are as good as can be would be another thing to look at. Exhaust brake will make descents more manageable as well

 

[icanfixall]

When you start getting near or above what the rig is rated for towing you make lots of trouble for yourself and others. Say you have 5.13 gears and are actually hauling 18,000 lbs with ease. Now think about attempting to stop that much weight. Its the brakes that really limits us as to what we can SAFELY haul. I recall some members mentioning hauling around 30,000 to scales... Tugging that much weight can be done but the truck can't handle that much on its back. I have hauled our fully loaded 5th wheel at about 12,000 lbs with 3.55 gears. The grapevine north from la is done around 55 mph where the Cajon pass to the south is done around 40 mph. My tandem trailer brakes are set up tight too. Being electric brakes that means tight brakes are dragging more than normal.

 

[IDIoit]

Harland sharpe roller rockers!!

I emailed them about a set, no reply.
I'll call them tomorrow