6 Cyl and 5 Speed

[66BlueGoose]

Does anyone have any information on doing a 5 speed with a 6 Cyl? Maybe the NV 3550? I thought I had seen an article or a post one one.

 

[Explorer]

bmbm is running one behind a 250ci.

 

[thegreatjustino]

Depends on the 6-cyl. With a 170, I'd be concerned with gearing the rear diff low enough to be able to use the overdrive.

 

[broncnaz]

The NV will be a little tough to do with smaller 6cyls due to clutch size and the need for a special clutch disc that along with the lack of power the small 6's already have your just not going to see any benefit from a OD tranny.
There's a reason the 6cyl broncos came with 4.10 r 4.56 gearing and 28in tires.

Basically the NV3550 will bolt up exactly like the V8 using the V8 adapter even. it just the clutch disc you will have issues with

 

[Broncobowsher]

The trans to bellhousing pattern is the same on the I6 and V8. Thus the hack V8 swap using the I6 transmission or the NP435 to I6 is completely possible and has been done many times.

The NV3550 adaptor changes the face of the NV3550 to bolt to a Ford bellhousing. So that part of the build is easy enough. The challenge is the clutch. The I6 clutch is smaller than the V8 so the disk in the swap kit for the V8 will be too large. At this point you are looking at finding or having a specialty clutch disk made. Maybe a pilot bushing as well.

 

[bmbm]

Ford made a 'large' bell 200 sometime after 78 I believe. That might solve the clutch problem if you wanted to go that far. Would have been in Fairmounts, Comets and others. Or a 250 would work with a M50 as well. But that wasn't your original question.

 

[Explorer]

I talked to either Novak or Advanced Adapters. They sell a kit, but I was told it included a Chev clutch disc. 10 spline to match the NV tranny and use the Ford pressure plate. Do your own research as it's been awhile and my memory doesn't retain info as good as it use to. I wrote the info down w/part numbers, but misplaced it.

 

[bigjhoov]

What 6cyl? I'm exploring this now.

The nv3500 uses an integrated bell housing, which is different than a 170/200 bolt pattern. I think the later 200 and the 240/300 have the v8 bolt pattern. And, there's the clutch issue.

 

[broncnaz]

The NV3550 is the transmission to use Im not sure anyone makes adapters for the 3500

 

[Broncobowsher]

What 6cyl? I'm exploring this now.

The nv3500 uses an integrated bell housing, which is different than a 170/200 bolt pattern. I think the later 200 and the 240/300 have the v8 bolt pattern. And, there's the clutch issue.

You are confusing the NV3500 and the NV3550.

 

[bigjhoov]

You are confusing the NV3500 and the NV3550.

Well, it appears that I am. I hadn't even considered the 3550. I'll look into it..

 

[66BlueGoose]

Hey all, Wow lots of good information!

The goal was to create a sister bronco to the one I own, the current one is a 66 with a 170 and is in the process of being restored to original condition (see my garage). As with any project, you start thinking about things you want to do and many of those don't fit with an original restoration. As such, I am planning to pick up another 66 and do LUBR Restomod. So while the new most likely comes with a 170 (assuming it has not been replaced), sky's the limit on engine choice, so a late model 200 or even a 250 would be an option.

Plan is for hopped up 6, 5 speed, some level of body / suspension lift. Tire size of 30 or 31. Then all the other stuff, all new electrics, modern interior, 4 wheel disc, Arb lockers, maybe a dana 40 up front.

Really interested in the combination bmbm has, you seem to have one already running.

 

[bmbm]

six/5spd

If you can start clean like that I would suggest the 250 but start looking now. Sometimes it takes awhile to find them but worth it- even stock a lot of low end torque. Get the 250 from about 78-81 it is the best base for modification. Early on I considered the 300 six, one of the best engines on the planet and it is 17% larger in displacement so it should have about that much more torque but it is heavier/larger and looked like a lot of work to install.
The nv3550 has good ratios, shifts good and is the best five speed for my setup. If doing it again though I would seriously consider the M50 trans. It shifts a little truck-like compared to the nv3550 but should cost a few dollars less for total install.
It's usually my daily driver and goes good on the highway and over mountain passes. I never hold up traffic and usually in the fast lane. Check out the fordsix.com website and forum there are members on there with six cylinder Broncos and at least a couple are 250 powered and also classicinlines.com for hop up info and parts.

 

[Broncobowsher]

A 250 is a huge step up from the 170. 80 cubic inch gain, nearly 50%. That like going from a 289 to a 427. But I wouldn't recommend a 300. Yes, they have a strong following. But they don't drop in like people have you thinking they do. They are long. The big block of the I6s. For the effort involved in a 300 swap there are a lot better options for a restomodded Bronco.