1972 F-250 2wd to 4wd build

[rattle_snake]

Did some more testing with the nitrous system. It 'works' but doesn't provide the increase I expect. Started with 50 hp jets, then 75 with -4* timing. You can feel some increase in power when coming on and off the WOT switch. 75/150 out of 425/525 is 17% hp and 28% tq. 28% tq should be quite noticeable.

Similarly my 2004 cobra has a 75/150 shot on top of 550 hp/550 tq and it is very obvious when system comes on.

AFR is rich low 12/high 11s so plan to go down 4 fuel sizes form a .022 to an .018

 

[rattle_snake]

Not that I should, but I got the truck over 100 mph today. Regular traffic is already 80, truck easily accelerated with more to go.
Got some driveline vibes on decel but only above 80.
For a big old pig with no sway bars it handles very good on the highway.

Still fighting the brakes puling left. This started after I had welded on the bump stops that are right next to the brake lines. Did R side first, frame got heated. On left side I welded half and waited for everything to cool, then did other half.
I have bled the brake twice now, complete reservoir amount. Issue still exists. stumped on this one at this time.

 

[350TacoZilla]

You thinking right side somehow deformed brake line and now left is getting more fluid so pulling left?

 

[arse_sidewards]

You thinking right side somehow deformed brake line and now left is getting more fluid so pulling left?

Should be easy to test. Just push the pedal slowly.

 

[rattle_snake]

Perhaps.
It pulls under all conditions, slow and easy braking or hard.

Fluid came out flowing the same on both sides when bleeding, which would indicate no restriction.

I had the brakes apart and inspected everything when doing the high steer arm.

Maybe it is rear brakes.

 

[rattle_snake]

Tested out the 0.041/0.018 nitrous/fuel jet combo. Much better, AFR in mid 12s similar to N/A. I think when it was too rich it lost half the power it was trying to add.
Now you can tell the solenoids are open.

 

[rattle_snake]

Took the truck out for a quick & simple desert camp trip with one of my daughters. Against better judgement I decided to try to mod platform and install camper the day I was trying to go. I had previously built a bed platform for use in my 2014 F250, in conjunction with the old camper shell. Didn't fit the 2014 well and leaked. Platform got revamped and modified for the 72 bed. Had to make it taller to work with spare tire, cutouts, brackets and so on.

Left side holds an isolated battery and a power panel. Main use is for high power audio system. Don't want to run off starting battery for obvious reasons. Cigar, dual USB, volt meter.

Using a 30Ah motorcycle battery with a voltage sensing isolator. The aux battery only gets charged when truck is running and alternator supply over 14v. I tapped into the trailer charge circuit at the rear bumper. Used a chunk of foam to hold battery in place, temporarily.

Got the old shell put on, cleaned up and sealed. home sweet home.

400W amp needs short heavy gauge wire to not sag voltage when sub hits. Luckily the sub box fits under the platform now.

Drove out to camp site near Peralta trail. It rained for a bit, stuff stayed dry so a win. New exhaust is too loud for long trips.

There were some trails with washes and some climbs so I took groups of peeps out for some wheeling.

Took one dog and she had a good time but passed out in the footwell on the way home.

 

[rattle_snake]

Finished out the nitrous system with a window switch. Not really needed with a manual trans but more or less required for launching an auto with a WOT switch. Torque converter stalls around 2300 and need to hold off nitrous until ~3000 RPM. Window switch allows going WOT from idle/stop. EFI is crisp and no bog/hesitation.
I tested with bottle off to make sure activation RPM was correct. Took my dad for a test drive and did a few launches. After purge the system comes on as expected and feels more like step function I expect, as throttle plates are already fully open. My dad commented on how much the truck leans/pulls left front up from torque, and then even more when nitrous kicks in. Good times. :)

Went with a Lingenfelter box as it had a positive N/O output, simple and priced reasonably.

 

[rattle_snake]

Well the trans is fucked. 3200 miles.

Started having issues of it not returning to 1st at a stop about 5 weeks ago (on camping trip of course). I checked everything I could including a fluid sample. Otherwise trans performed as expected. Stayed nice and cool with huge cooler.

Having been through similar issues before I figured the fluid is contaminated with particles causing the pistons in the governor to stick most of the time but not all. So I drained and pulled the pan. Not good.

I have 2 options
a) Fix the C6. Replace cooler, torque converter. Around $1400, Truck down for 4-6 weeks
b) Go to a 6R80/100. Used trans, adapters, controller, driveshaft mods, crossmember mods, replace cooler, new lines. $4.5-5k, 12+ weeks

6R has a 4.17 first and 0.69 6th yielding a 6:1 gear spread. C6 is 2.40 first and spread. So first would be geared down by 1.73 which is almost like having a doubler. It will burn the tires off like it does in 2WD low now. The relatively shallow 2:1 of the NP205 is offset with a steep 1st.
Overdrive of 0.69 puts 75 MPH cruise at 1800 RPM with help from lockup converter. 5th is 0.87 and would be 2300. I think the lockup converter will help $/mile and increase range.

It's just time and money. Instead of enjoying wheeling it. But I like to design and fab.

 

[rockota]

b) Go to a 6R80/100. Used trans, adapters, controller, driveshaft mods, crossmember mods, replace cooler, new lines. $4.5-5k, 12+ weeks

if I get a vote, it's this. Just for the coolness factor

 

[rattle_snake]

Yes, anyone can vote these days it's just my time and money.

Note there is no correlation to trans failure right after nitrous install

 

[TrikeKid]

If it were my money, it'd get the C6 replaced (Well, actually, it would've had a clunky ass NP435 from the get go). 6R80 is my favorite Ford automatic by far but like you said, pretty healthy investment to make em work in an old rig behind an old engine.

 

[Snowracer]

ZF mans trans

 

[rattle_snake]

E4od off the table?

No not really. In planning stage at this point.

2.7 first, better but not great
0.7 OD is good enough.
Has lockup converter
Core, rebuilt trans, converter, controller, cooler, line, ect, Built enough for my N20 BBF, $4K
8" longer so same crossmember/driveshaft issues.

 

[rattle_snake]

ZF mans trans

I row a 6 speed in my cobra but not a fan of 3rd pedal while wheeling.
6k launch on slicks, 15psi boost + N20, bang 4 gears Twin disc clutch, 26 spline input shaft.

 

[reptillikus]

I hear you on that one, id really like another gear in my bronco but dont like the idea of crawling with a manual.

Advance Adapters website says The 6R80 is 23.75". The E4OD is over 31". If im not mistaken, that makes the 6R80 actually shorter than the C6.

Im a big fan of the 6R80, a buddy is currently in progress putting one in his bronco and id kinda like one in mine, if it wasnt for the price tag to get it in there.

 

[Snowracer]

I row a 6 speed in my cobra but not a fan of 3rd pedal while wheeling.
6k launch on slicks, 15psi boost + N20, bang 4 gears Twin disc clutch, 26 spline input shaft.

feel like for a street driven rig that i dare even say is "overland-ish" a stick is a good options as deeper 1st and good overdrive. yes not as good for crawling as the auto

so in that case i say do the 6R80 and do a right up on it so i can copy it for my buggy and have paddle shift and 6 speeds for go fast fun

 

[rattle_snake]

My C6 case is about 20" and 29 with tail shaft adapter.

I have not found a 6R to NP205 adapter, however it seems 205 = dana 300 = atlas. There is an atlas one, about 3.6" long. engine to trans adapter adds about 2". So total around 29, hmmm....

 

[rattle_snake]

I pulled the trans filter to ensure complete fuckery before buttoning up the trans for cleaning.

Yep, shavings embedded and on clean side.

This one time I was smart enough to pressure wash the underside BEFORE working on it. Then I drained and disposed of $200 worth of fluids that didn't need to be changed instead of spilling shit all over during disassembly. Slow learner but getting there....

 

['84 Bronco II]

That all sucks to hear, but a 6R80 would be an awesome upgrade for that truck. I definitely want to see you make it happen

 

[rattle_snake]

yes, 3200 miles is not much for my investment in the c6. I have bad luck with rebuilds of auto transmissions.

Pretty much committed to the 6R swap now, getting excited about laying rubber with the low 1st gear.

 

[ZSK]

Hellwig 68 Bronco Project

God I love shiny new parts :) I know! And it's weird not having rust and grime on all the bolts and stuff just unthreading/threading no problem. I'm getting spoiled... So we've basically just been catching up on R&D stuff all week and will be for probably the next month or so. We've knocked...

forum.ih8mud.com

Some good pictures of the adapter and linkage to an Atlas case. After poking around a bit, verify the engine to trans adapter you're using. Some utilize the 3.5 6R case for a two bolt starter mount, and some use the Coyote case for a three bolt starter.

 

[rattle_snake]

Thanks I was wondering about shifter mounting. He running an atlas with the old Tumbin adapter that is no longer available.

The PA adapter is only for the 3.5t bell, and is 3-4 month back order.
Speed Gem is 3x the cost and is for the modular bell, in stock

I called Advance Adapters and they said the 6R80 to atlas version will allow a 205 to bolt up with only clearance for shift rails. They had one in stock so I bought it, $500 delivered. Hope I can clock 205 up a bit.

Called Speed Gem and got adapter thickness, 2.000". This should put entire assembly at 29.375", C6 + tail adapter is 29 so shoudl be able to use both driveshafts as is. I want to be able to use a 6r100 so mod bell it is, so I ordered the SG FO2501 with a quick shift 6. $3150 delivered.

Lots of items to work though, cooler lines, shift mechanism (hope to use OG column shifter), trans mount, and so on.

 

[rattle_snake]

Got the transfer case off the truck last night. NP205 is too heavy to manhandle myself. So I built a temporary steel contraption that has a flat bottom to ease the process. Lowered truck onto tool cart and attempted to slide it back off the trans. Case was hitting cab floor, so had to removed some shims on trans mount to get assembly lower and case out. Need to redo the clearancing on the cab floor.

Plan to pull motor and trans out together after front clip is off, which has it's own set of issues and modifications needed.

 

[rattle_snake]

MF'n PTO cover has a slight leak. Gasket or no? Just RTV?

Maybe I can use the divorced mount tapped holes on the side to make a shifter mount contraption.

 

[rattle_snake]

Prep for pulling drivetrain.

Bumper in the way, heavy with winch. Used fab table and jack to remove without lifting.

Rolled it over to the bed and slid it in to store for now. One man show.

Spiffed up the driveshafts. Rear wasn't repainted when first installed. It was boxed up and shipped before original paint dried, so did some prep and painted.

Hacked up the core support to allow the A/C condenser to be left attached to the rest of the system. Glad I converted to 134 but would rather not open the system. Going to make some type of removable patch/reinforcement panel. Core support didn't have much attached to it and came off easy enough.

Pulled most of the accessories off the motor in prep for removal. Wiring is all connectorized, but will make some changes to how things are secured to engine. P/S and electrical system left intact. Headers had to come off. Ready to come out.

 

[rattle_snake]

Before moving truck out of lift bay I addresses the cab/transfer case interference issue. The original cab cross member support did not allow TC to be slid back and removed.
Before:

So fix was to cut the rest of the way through and widen the notch considerably.
After:

Cut out the old and weld in the new. When overhead welding it is worth the time to REALLY CLEAN everything to minimize splatter onto one's self.

Rattle can satin black and done.

 

[rattle_snake]

Pull the motor without too much trouble. Had to find the right chain link to balance the assembly at the right angle to pull it up and out.

Built a engine stand out of some scraps to support from chassis mounts, so I can fart with transmission adapters.

Then the big question, where is that MF'n oil leak from? Rear main?
It appears to be the oil pan gasket and the right valve cover. There are a few rust spots on the rear of the crank that would suggest it was not coming from the rear main seal. The thin separator plate had the smoking gun. I had resealed the valve cover previously. So no need to do RMS job, yay for me.
But I am going to replace the oil pan and valve cover seals, among other things.

Piling all the parts into the bed to store once they are ready to be put back on. Having to clean up a lot of fasteners and such that are all oily from the various leaks some of which are already fixed. Front end is up quite a bit with weight missing.

 

[rattle_snake]

Received the adapters for both ends of the 6R. 460->6R80->NP205/atlas
The engine adapter is 2" thick to solve the starter location differences, as is torque converter spacer.

The transfer case adapter is for an AA atlas, but has same bolt pattern as many other TCs including NP20x, BW, Dana and so on.
But for use on 205 there are mods needed. The gear drive 205 has shift rails close to input centerline so need to hog out that area.

Once I had basic fitment I see that the idler shaft is in the way, so poked around in the tooling and found a suitable cutter.

But then the input bearing retainer didn't clear so did some more machining of adapter to allow it to sit flush on face. Still need to go further on shift rail as the shifter itself uses a thicker collar. I think I have a boring bar that will work.

 

[Snowracer]

fuck yes i can wait to watch this swap