IDI in Half Ton: MPG & Suspension

[bike-maker]

I used to have a 82 F150 stepside that had numerous engines; from a 300-6 to a 351W to a 514" big block that made more torque than just about any IDI could. And I drove it HARD (I was a teenager at the time). Only drivetrain parts I blew up was trashing the bearings in the 9" rear end. I think it would hold up just fine, but you're going to need some beefier springs - my truck was lowered so the extra squat on the front end wasn't an issue for me.

 

[Simp5782]

I had an old 4x4 80 F-150 with a 302. junked it and slapped in a 76 Thunderchicken 460. she was a screamer. I got like 8 or 9, with the c6 but after awhile the TTB didnt like it very much. started to sag overly. I still wonder what happened to that truck. I sold it for $1500. I put alot of work into it. One of my many sell offs when I was younger I regret now.

 

[phazertwo]

I bet the 8.8 holds up fine to a NA engine. They are serious up grades for jeeps with 4.0s and big ass tires. I bet a 4.0 makes close to as much tq as a 6.9 idi NA

IF you plan to turbo, better be looking into a f250 drive train....

PZ

 

[Pino2234]

Thanks guys I think I'm sticking with the 1/2 drivetrain. After all my F350s have 8 lugs but they also are capable of towing 10,000lbs. I'm not towing anything with this Bronco so it should be ok.

Noone has any MPG stats that they can post? Trying to get an estimate on where I'll be. If I get over 20 miles per gallon I will be happy. 25 is what I'm shooting for though.

 

[Optikalillushun]

Id venture to say 20 would be really easy to get and 25 with some good driving. Going auto or stick?

 

[Pino2234]

Id venture to say 20 would be really easy to get and 25 with some good driving. Going auto or stick?

First is a C6 probably because I have one ready to go with a new torque converter. I need to stop driving my dually to work everyday but when I rebuild my E4OD that's going right in.

 

[Agnem]

The best I could do on a regular basis with my 6.9/C-6/3.54 powered Bronco was 17. The C-6 is just a milage killer.

 

[trapper]

hey mel what do you think ill get in my 150 zf5 and i believe to be 3.55's

 

[plywood]

How 'bout converting a Bronco to 2wd, lower it a little, with an IDI and overdrive it should see 25 easy.

 

[snicklas]

Trapper,

Looking at the this thread from Mel on the 2010 Rally Fuel Economy Thread, that the Night Moose (A 94 F-150 Flareside 6.9/ZF-5/3.54) averaged a bit over 29 on the trip.... so I would think you could get high 20 if not almost 30 like Graham did.....

 

[Pino2234]

The best I could do on a regular basis with my 6.9/C-6/3.54 powered Bronco was 17. The C-6 is just a milage killer.

Mel you have a zf5 now? What's that getting?

How 'bout converting a Bronco to 2wd, lower it a little, with an IDI and overdrive it should see 25 easy.

It ain't a truck without 4 Wheel Drive lol. I would love the 4X4 fuel mileage combo.

 

[trapper]

if i get 20-25 mpg ill be happy

 

[Pino2234]

if i get 20-25 mpg ill be happy

We'll find out, hopefully soon.

 

[seawalkersee]

You won't get 20. That being said, I have 33s and 3.5 gears with a NP435 4spd. I am not quite sure what it is gettting now, but prior to my rebuild, I was at 18. If you beat on it at lower RPMs, its easier on the fuel than at higher RPMs. Like spinning the tires off the line and such. But go 65 and hammer it to get to 75 and it sucks the fuel. It takes a ton of HP to make 10mph over 50.

With that, I had a donor for my bronco. I snagged the 250 springs out of the 2wd and it raised the front end up higher than the rear end. Not a lot, but it is higher. Now, the camber is out at the top. Not bad, but it is starting to show after I drive it (inside lugs are all dusty). The tranny came out of a 76 (I think) highboy and the rest of the drivetrain is factory 84 fresh.

Ripped off the rear bumper pulling out a tree, but that was because the welds had rusted to the point that there was more surface area of a penny than weld on the driver's side. As long as rust is not a problem and bolts/bushings are in good working order, you should be okay.

Since my tach does not work, I do not know what my RPMs are at speed, but I KNOW an overdrive would do me some good.

SWS

 

[1800joedaddy]

Napa carries the U-joint to mate the drive shaft to 8.8 yoke.
#459 precision.