'71 Bronco Build / Retrospective
#31
11-25-2013, 12:57 PM
I can't believe a F150 steering box on the outside of the frame mod was not in there some where, lots of info on the web about it these days.
West Coast Broncos
West Coast Broncos
#32
11-25-2013, 03:30 PM
Nice work! It's lookin good.
Couple comments here for you... As you've discovered, the newer 302's (HO's) did not have the bolt hole for the clutch bell crank, but the Bronco vendors sell a bracket just for this... EFI Clutch Equalizer Bracket, 66-77 Ford Bronco, New - Toms Bronco Parts. This is just an after thought since you already made your own that seems to work just fine.
When Ford changed the 302 to the High Output (HO) motor (and the firing order to the 351 firing order), they also changed the balance from 28oz to 50oz. So, older 302's and all 351's have a 28oz counter balance, while the newer HO 302's are 50oz. So if you ever decide to chage to a 351, you'll need a new flywheel, again.
My personal opinion here is that the ZF is the cheapest 5spd conversion for a couple reasons:
1. It's a Ford tranny, so no adapter needed at the bellhousing. You can usually find an old F250 for less than $1000 and you can pull the tranny and hydraulic clutch then sell the rest. I picked up a '90 F250 for $450.
2. You can bolt an NP205 tcase right up by just cutting a notch in the tailhousing. If you stay with the D20, the adapter alone is less than $400 (you can make your own crossmember for fairly cheap). The NV3550 Deluxe Kit is over $1000! A third option is to use the NP203/205 dual case setup.
I think your only option here with the 9" is a Warn full floating axle kit, which I don't think they make anymore, so they are hard to find and spendy. Here's one that may still be availble... NC Warn full float kit 76-77 BB - ClassicBroncos.com Forums
The only issue I had reinstalling the trans was that the replacement engine didn't have one of the bosses for the clutch linkage. After staring forlornly up at it from a creeper for a while I figured out a way to tie the missing mounting point into the bellhousing. It's not as solid as the original, but it's plenty strong in the direction it needs to be.
The other issue was that once it was all back together I had a pretty noticeable vibration. Turned out that the engine I got the flywheel from (as well as all older 302s apparently) was "externally balanced" while my rebuilt engine was "internally balanced". The correct flywheel, along with another new clutch (the other new clutch didn't line up with the holes in the new flywheel) and I was running smooth again.
The other issue was that once it was all back together I had a pretty noticeable vibration. Turned out that the engine I got the flywheel from (as well as all older 302s apparently) was "externally balanced" while my rebuilt engine was "internally balanced". The correct flywheel, along with another new clutch (the other new clutch didn't line up with the holes in the new flywheel) and I was running smooth again.
When Ford changed the 302 to the High Output (HO) motor (and the firing order to the 351 firing order), they also changed the balance from 28oz to 50oz. So, older 302's and all 351's have a 28oz counter balance, while the newer HO 302's are 50oz. So if you ever decide to chage to a 351, you'll need a new flywheel, again.
5 speed trans and crawler transfer case
I want lower gears for rockcrawling and higher gears for the freeway. 4:1 t.case gears will take care of the low end, but will require a pretty wide spread between low and high in the tranny to prevent a big "dead zone" between low range and high range. A 5 speed overdrive will do that as well as address my freeway gearing.
An NV4500 trans and a 3- or 4-speed Atlas t.case would be my top choice for strength and range of ratios. But realistically I'm leaning toward the NV3550 as being easy to shift and easier to install, and a 2 speed Atlas for cost. A T-18 or NP435 4 speed would be another option for the trans, but then I'd need to regear the axles to take care of the freeway ratio, and that gets too expensive.
There's some small chance that I might start this project this winter. I'm still in the process of selling my 2002 F-350 crew cab diesel. If there's enough money left over from that sale I might put it here. But more realistically it's farther out.
I want lower gears for rockcrawling and higher gears for the freeway. 4:1 t.case gears will take care of the low end, but will require a pretty wide spread between low and high in the tranny to prevent a big "dead zone" between low range and high range. A 5 speed overdrive will do that as well as address my freeway gearing.
An NV4500 trans and a 3- or 4-speed Atlas t.case would be my top choice for strength and range of ratios. But realistically I'm leaning toward the NV3550 as being easy to shift and easier to install, and a 2 speed Atlas for cost. A T-18 or NP435 4 speed would be another option for the trans, but then I'd need to regear the axles to take care of the freeway ratio, and that gets too expensive.
There's some small chance that I might start this project this winter. I'm still in the process of selling my 2002 F-350 crew cab diesel. If there's enough money left over from that sale I might put it here. But more realistically it's farther out.
1. It's a Ford tranny, so no adapter needed at the bellhousing. You can usually find an old F250 for less than $1000 and you can pull the tranny and hydraulic clutch then sell the rest. I picked up a '90 F250 for $450.
2. You can bolt an NP205 tcase right up by just cutting a notch in the tailhousing. If you stay with the D20, the adapter alone is less than $400 (you can make your own crossmember for fairly cheap). The NV3550 Deluxe Kit is over $1000! A third option is to use the NP203/205 dual case setup.
Rear locking hubs
They make it so much easier to flat tow when you don't have to crawl underneath to remove and then reinstall the rear driveshaft. This might require switching to a different axle, like maybe a D44, if I can't figure out how to do it on a 9". We'll have to see how often we go fourwheeling as empty-nesters to see if it'll be worth doing this.
They make it so much easier to flat tow when you don't have to crawl underneath to remove and then reinstall the rear driveshaft. This might require switching to a different axle, like maybe a D44, if I can't figure out how to do it on a 9". We'll have to see how often we go fourwheeling as empty-nesters to see if it'll be worth doing this.
#33
11-25-2013, 04:30 PM
I can't believe a F150 steering box on the outside of the frame mod was not in there some where, lots of info on the web about it these days.
West Coast Broncos
West Coast Broncos
#34
11-25-2013, 04:44 PM
My personal opinion here is that the ZF is the cheapest 5spd conversion for a couple reasons:
1. It's a Ford tranny, so no adapter needed at the bellhousing. You can usually find an old F250 for less than $1000 and you can pull the tranny and hydraulic clutch then sell the rest. I picked up a '90 F250 for $450. I haven't dug into all of the details yet, but this is a good option to consider.
2. You can bolt an NP205 tcase right up by just cutting a notch in the tailhousing. If you stay with the D20, the adapter alone is less than $400 (you can make your own crossmember for fairly cheap). The NV3550 Deluxe Kit is over $1000! A third option is to use the NP203/205 dual case setup. An NP205 has a taller low range (1.96:1) than a Dana 20 (2.46:1). My crawl ratio is my biggest problem, so an NP205 isn't under consideration. And as I understand an Atlas t.case mounts pretty much like a Dana 300, so it ought to go right on an NV3550, maybe easier than a ZF. So t.case connections are in favor of a NV3550 in my case.
1. It's a Ford tranny, so no adapter needed at the bellhousing. You can usually find an old F250 for less than $1000 and you can pull the tranny and hydraulic clutch then sell the rest. I picked up a '90 F250 for $450. I haven't dug into all of the details yet, but this is a good option to consider.
2. You can bolt an NP205 tcase right up by just cutting a notch in the tailhousing. If you stay with the D20, the adapter alone is less than $400 (you can make your own crossmember for fairly cheap). The NV3550 Deluxe Kit is over $1000! A third option is to use the NP203/205 dual case setup. An NP205 has a taller low range (1.96:1) than a Dana 20 (2.46:1). My crawl ratio is my biggest problem, so an NP205 isn't under consideration. And as I understand an Atlas t.case mounts pretty much like a Dana 300, so it ought to go right on an NV3550, maybe easier than a ZF. So t.case connections are in favor of a NV3550 in my case.
I think your only option here with the 9" is a Warn full floating axle kit, which I don't think they make anymore, so they are hard to find and spendy. Here's one that may still be availble... NC Warn full float kit 76-77 BB - ClassicBroncos.com Forums
#35
11-25-2013, 05:02 PM
An NP205 has a taller low range (1.96:1) than a Dana 20 (2.46:1). My crawl ratio is my biggest problem, so an NP205 isn't under consideration. And as I understand an Atlas t.case mounts pretty much like a Dana 300, so it ought to go right on an NV3550, maybe easier than a ZF. So t.case connections are in favor of a NV3550 in my case.
#36
11-25-2013, 06:08 PM
#37
11-26-2013, 09:53 AM
For strength and durability, I'd go with the ZF option. The NV4500 is a tough ******* as well but, the NV3550 is built for a much smaller/lighter Jeep. When I was in the Jeep world, I didn't have problems with mine. But, I do know a few who did. BUT... you seem to be sticking to 33s or smaller tires. The NV3550 may be a viable solution depending on how tough "wheeling" your doing.
Good thread. Good read. Makes me motivated to get back into an EB A.S.A.P.
Good thread. Good read. Makes me motivated to get back into an EB A.S.A.P.
#38
11-26-2013, 12:22 PM
For strength and durability, I'd go with the ZF option. The NV4500 is a tough ******* as well but, the NV3550 is built for a much smaller/lighter Jeep. When I was in the Jeep world, I didn't have problems with mine. But, I do know a few who did. BUT... you seem to be sticking to 33s or smaller tires. The NV3550 may be a viable solution depending on how tough "wheeling" your doing.
Good thread. Good read. Makes me motivated to get back into an EB A.S.A.P.
Good thread. Good read. Makes me motivated to get back into an EB A.S.A.P.
However a Bronco ain't no 3/4 ton truck either. With a relatively low torque 302 in front of it I don't think I'm too likely to break it. I'm not going to be towing anything heavy with it (I've got the F-250 for that). And with a 4:1 t.case I won't be working the trans as hard in low range either.
I plan to stay with 33s on the road. I might go up to 35s for off-road. But again, with a 4:1 t.case that shouldn't present a problem for an NV3550. And I don't 'wheel like a teenager either. I was a teenager once, but it was a loooooong time ago
#39
11-27-2013, 11:01 PM
NV3550's got it all over the quoted Mazda.
the 4500 and ZF obviously go it one better yet,
U can ask Atlas about the adapter - if needed ($400?).
I'd just make one at a friend's or a shop 4 that price.
There's also some gears to rebuild the D20 MUCH
lower. Solves lots of problems (but U know what THAT
means - big bucks). Put any kinda rear gear, transmission,
locker, breaks, etc.
the 4500 and ZF obviously go it one better yet,
U can ask Atlas about the adapter - if needed ($400?).
I'd just make one at a friend's or a shop 4 that price.
There's also some gears to rebuild the D20 MUCH
lower. Solves lots of problems (but U know what THAT
means - big bucks). Put any kinda rear gear, transmission,
locker, breaks, etc.
Last edited by chrlsful; 11-27-2013 at 11:16 PM. Reason: JBG rebuild D20
#40
01-21-2014, 12:07 PM
Transmission and transfer case - 2014
OK, time to get started again. I've got an NV3550 coming. I decided against a ZF (didn't want to mess with a hydraulic clutch linkage or need to get a spacer or shorten the output shaft to mount an Atlas) and an NV4500 (more expensive, heavier and harder shifting). The 3550 should be plenty of trans behind my stock 302 and will almost bolt right up (I'll need an adapter between the bellhousing and trans and a new clutch disk, both available from Jeff's and probably others).
Next is to decide on the transfer case, or more accurately, the gearing. I'm planning on going with an Atlas. The crawl gears ought to make my 302 just fine for rock crawling so I don't have to think about a 351 swap. I'm thinking I'll probably go with 4.3:1 gearing, but a 4 speed Atlas would be really cool (and really expensive). I've started a thread on the Offroad forum asking for advice on the t.case gearing. Please feel free to drop by here https://www.ford-trucks.com/forums/1...l#post13979551 and chime in if you have suggestions for me!
Hopefully I'll start turning wrenches on this within the next couple of weeks! I'll keep you posted.
Next is to decide on the transfer case, or more accurately, the gearing. I'm planning on going with an Atlas. The crawl gears ought to make my 302 just fine for rock crawling so I don't have to think about a 351 swap. I'm thinking I'll probably go with 4.3:1 gearing, but a 4 speed Atlas would be really cool (and really expensive). I've started a thread on the Offroad forum asking for advice on the t.case gearing. Please feel free to drop by here https://www.ford-trucks.com/forums/1...l#post13979551 and chime in if you have suggestions for me!
Hopefully I'll start turning wrenches on this within the next couple of weeks! I'll keep you posted.
#41
03-15-2014, 06:39 PM
Getting the transmission
It’s been slow, but I am making progress on my transmission / transfer case swap. I’ve finally got to a point where it’s worth an update.
The first order of business was getting a “complete” transmission. That was more complicated than I expected. I found an NV3550 on line, out of a 90K mile 2002 Jeep Wrangler. I asked if it was complete, but I should have been more specific. It came with a bellhousing and throwout fork/bearing (which I didn’t need), but not with the shifter, which I did need. When I called about it, the place I got the trans from no longer had the shifter, so that started another search.
I found a “complete” shifter from another ’02 Wrangler. But when it arrived it was missing the “shifter pivot ball cup” (a plastic piece that snaps onto the ball on the end of the shift lever and slips into a sleeve in the top of the trans connected to the internal shift linkage. Another internet search had a new one on it’s way. And it was also missing the “rubber shifter gasket.” I thought at first I might just be able to use RTV, but it turns out the actual part is molded and is about 3/8” thick. So another internet search had a fourth package coming my way, and finally I had a complete transmission!
The transmission as received
The shifter, after installing the shifter pivot ball cup
The (finally) complete trans!
The first order of business was getting a “complete” transmission. That was more complicated than I expected. I found an NV3550 on line, out of a 90K mile 2002 Jeep Wrangler. I asked if it was complete, but I should have been more specific. It came with a bellhousing and throwout fork/bearing (which I didn’t need), but not with the shifter, which I did need. When I called about it, the place I got the trans from no longer had the shifter, so that started another search.
I found a “complete” shifter from another ’02 Wrangler. But when it arrived it was missing the “shifter pivot ball cup” (a plastic piece that snaps onto the ball on the end of the shift lever and slips into a sleeve in the top of the trans connected to the internal shift linkage. Another internet search had a new one on it’s way. And it was also missing the “rubber shifter gasket.” I thought at first I might just be able to use RTV, but it turns out the actual part is molded and is about 3/8” thick. So another internet search had a fourth package coming my way, and finally I had a complete transmission!
The transmission as received
The shifter, after installing the shifter pivot ball cup
The (finally) complete trans!
#42
03-15-2014, 06:43 PM
Adapting the NV3550 to the Ford bellhousing - Mar 2014
Removing the old trans and t.case went a lot slower than it should have due to the weather. Working in an unheated garage at 0 F doesn’t let you work very long before you need to go in and thaw your hands! That and the fact that I still didn’t have the complete trans yet led to disassembly taking a full month (working only on Saturdays). Nothing very exciting, and no pictures, so it’s not worth it’s own post.
I ordered the NV3550 to Ford bellhousing adapter from Jeff’s. It came with an adapter plate to mate the new trans to the original bellhousing as well as a clutch disk that would fit the NV3550 input shaft, but work with the original Ford flywheel and pressure plate. Jeff’s web site said that the stock bellhousing would require slight modification, which it did. But when the adapter came, the instructions said it also required slight mods to the transmission case, and to the input shaft.
The trans case mods were simple, just filing a relief for two of the bellhousing bolts in the aluminum trans mounting flange. No sweat.
The bellhousing mod did involve some sweat, even though it had only warmed up to 30 F. A 3/8” wide slot in the top of the bellhousing needed to be opened up to about a 1 ¼” hole to clear a boss on the front of the trans. Since the bellhousing is cast iron and relatively thick, that was a lot of work using only a hack saw and a round file. Nothing too involved though, just a lot of elbow grease.
So now I have the trans and bellhousing together. The next thing to do is to shorten the pilot stub on the end of the input shaft. I’m not quite sure how I’m going to do that yet. Probably with an angle grinder, but I don’t want to overheat the input shaft so it loses it’s temper. I’ll probably give Advance Adapters a call and see what they recommend.
Other than the input shaft mod, the next thing to do is order the transfer case. I’ve decided on an Atlas 4.3:1 2-speed. I plan to get that ordered next week. Hopefully it’ll all be back together and running by about mid April.
Bellhousing mods
Trans and bellhousing
I ordered the NV3550 to Ford bellhousing adapter from Jeff’s. It came with an adapter plate to mate the new trans to the original bellhousing as well as a clutch disk that would fit the NV3550 input shaft, but work with the original Ford flywheel and pressure plate. Jeff’s web site said that the stock bellhousing would require slight modification, which it did. But when the adapter came, the instructions said it also required slight mods to the transmission case, and to the input shaft.
The trans case mods were simple, just filing a relief for two of the bellhousing bolts in the aluminum trans mounting flange. No sweat.
The bellhousing mod did involve some sweat, even though it had only warmed up to 30 F. A 3/8” wide slot in the top of the bellhousing needed to be opened up to about a 1 ¼” hole to clear a boss on the front of the trans. Since the bellhousing is cast iron and relatively thick, that was a lot of work using only a hack saw and a round file. Nothing too involved though, just a lot of elbow grease.
So now I have the trans and bellhousing together. The next thing to do is to shorten the pilot stub on the end of the input shaft. I’m not quite sure how I’m going to do that yet. Probably with an angle grinder, but I don’t want to overheat the input shaft so it loses it’s temper. I’ll probably give Advance Adapters a call and see what they recommend.
Other than the input shaft mod, the next thing to do is order the transfer case. I’ve decided on an Atlas 4.3:1 2-speed. I plan to get that ordered next week. Hopefully it’ll all be back together and running by about mid April.
Bellhousing mods
Trans and bellhousing
#43
03-16-2014, 08:31 PM
seeing the shifter in your pic made me think you'd need to bend it to fit, just incaqse no 1 local in CO has a 3550 here's a link to one:
NV 3550 Install | ClassicBroncos.com Tech Articles
looks like no bending needed, eh?
Can you tell me how much for the engine/transmis adapter from Jeff's?
Have you designed the transmission or transfer x-member?
NV 3550 Install | ClassicBroncos.com Tech Articles
looks like no bending needed, eh?
Can you tell me how much for the engine/transmis adapter from Jeff's?
Have you designed the transmission or transfer x-member?
#44
03-16-2014, 10:31 PM
Thanks for the link. I haven't had time to read through it yet, but at first glance it sure looks like something I want to work through when I get a chance.
The adapter plate and clutch disk were $255 NV3550 to Ford Bellhousing Adapter
I haven't decided on the crossmember yet. Jeff's has an Advance Adapters one for $199 NV3550 Bronco Crossmember It says it needs to be modified when used with an Atlas. I might go that route if I decide I want to get it done as quick as possible. Otherwise I'm sure I can make one for a lot less than that, it'll just take me longer. I'm a little on the clock here because I need the Bronco and truck both ready for a family vacation in July, and there's a pretty long list of smaller projects on the truck (as well the rest of life interfering with truck projects), so I really want the Bronco running before May.
The adapter plate and clutch disk were $255 NV3550 to Ford Bellhousing Adapter
I haven't decided on the crossmember yet. Jeff's has an Advance Adapters one for $199 NV3550 Bronco Crossmember It says it needs to be modified when used with an Atlas. I might go that route if I decide I want to get it done as quick as possible. Otherwise I'm sure I can make one for a lot less than that, it'll just take me longer. I'm a little on the clock here because I need the Bronco and truck both ready for a family vacation in July, and there's a pretty long list of smaller projects on the truck (as well the rest of life interfering with truck projects), so I really want the Bronco running before May.
#45
03-19-2014, 08:32 AM
2 kinds of adapters
"...need an adapter between the bellhousing and trans..."
Is this kind of adapter like a "block plate"? specific to thqat motor & the NV? just "locates" things? Like 2 C a pic (again, if I need it w/the 4.1/NV/D30, I have to come up w/it myself. Even $255 w/clutch is a stretch 4 me).
I only know about ones that R used at the tranmis/transfer.
Sounds like the atlas/nv wont need one to mate? only a clearence w/the grinder?
"...I haven't had time to read through it..."
May B I should look myself - to C if the D30 and NV need an adapter. It may not B in that "master" thread/stickie whatever U wanna call it. I read a member's nv thread elsewhere, may have more detail (esp where he ran into trouble - bein a 'non-mechanic' like me) & lots more pic.
Is this kind of adapter like a "block plate"? specific to thqat motor & the NV? just "locates" things? Like 2 C a pic (again, if I need it w/the 4.1/NV/D30, I have to come up w/it myself. Even $255 w/clutch is a stretch 4 me).
I only know about ones that R used at the tranmis/transfer.
Sounds like the atlas/nv wont need one to mate? only a clearence w/the grinder?
"...I haven't had time to read through it..."
May B I should look myself - to C if the D30 and NV need an adapter. It may not B in that "master" thread/stickie whatever U wanna call it. I read a member's nv thread elsewhere, may have more detail (esp where he ran into trouble - bein a 'non-mechanic' like me) & lots more pic.