170 c.i. Motor

[Cool67]

Is there enough difference that will be an issue using a 170 from an early mustang in a 66 bronco? If it is not a problem can I use the flywheel ,pressure plate,clutch and bellhousing from the 170 c.i. mustang ? My chassis has a stock 3 speed trans in it now. So in other words will it all bolt up?

 

[Broncobowsher]

My understanding is it will bolt up. But don't toss the Bronco one too fast. There will be a handful of trinkets that are Bronco specific.
I recall that HP is down slightly in the mustang, has the hydraulic cam, and missing every other main bearing. There are differences. But it could be made functional.

 

[73azbronco]

Things I know are different, the carb, keep the bronco one. The linkage is unique to the EB

 

[Cool67]

I have no old existing motor at all to swap anything but the drivetrain and trans were for a 6 cylinder and not super worried about any power difference or originality .

 

[B RON CO]

Hi, early 144, 170, and 200 engines are drilled for the small bell housing so the large bell housing for the mighty 9" clutch will not fit. Starting with the 66 Bronco, the 6 cylinder blocks were drilled with a dual bolt pattern for both size bell housings. In 67, all the cars went with the new 3.03 tranny, but the C4 kept the small bell housing. Good luck

 

[Cool67]

So I guess my next question is will the early 170 motors ( small ) bellhousing fit my stock 3 speed bronco transmission?( the trans is an original bronco 3 speed manual trans.

 

[Broncobowsher]

I would defer you to the fordsix website for better details.

My understanding is the big bell, low starter mount, was much later blocks. Late 70s?
Never heard any differences on the small bell, high starter engines.

The straight 6 isn't very popular around here. Most are just pulled out and a V8 swapped in. Or keep the original engine. Not much for swapping between different 6s. Thus the straight 6 ford specific website should have better details for what you are after.

 

[bmbm]

A six from a passenger car came with a front sump oil pan and the six for the Bronco came with a rear sump pan so you will need to find a rear sump pan for clearance with the front diff.

 

[bmbm]

Along time ago I swapped my 170 out for a late 70's Fairmount 200. Details are not clear at this stage but I believe it was a bolt in swap as far as fitment. You will need the Dana 20 transfer case and there is a intermediate adapter housing? kind of thing in there also. Those came in two lengths so get the one for the six it is shorter as I recall.

 

[bmbm]

Intermediate housing looks like thus:

https://shop.broncograveyard.com/Intermediate-Housing-manual-6-Cylinder/productinfo/11021/

It would help to get the spudshaft and dana 20 drive gear.

 

[jamesroney]

I would defer you to the fordsix website for better details.

My understanding is the big bell, low starter mount, was much later blocks. Late 70s?
Never heard any differences on the small bell, high starter engines.

The straight 6 isn't very popular around here. Most are just pulled out and a V8 swapped in. Or keep the original engine. Not much for swapping between different 6s. Thus the straight 6 ford specific website should have better details for what you are after.

I would defer you to our site. We have great details. Some of us are just reluctant to reply, because it ends up consuming too much bandwidth for questions that have been asked, and answered. @B RON CO gave you 100% correct advice, and if you read his post, it answers your question PERFECTLY. I usually don't answer first posts from people that aren't willing to fill in their profile.

Is there enough difference that will be an issue using a 170 from an early mustang in a 66 bronco? If it is not a problem can I use the flywheel ,pressure plate,clutch and bellhousing from the 170 c.i. mustang ? My chassis has a stock 3 speed trans in it now. So in other words will it all bolt up?

But I will answer even better.
1. "Is there enough difference that will be an issue using a 170 from an early mustang in a 66 bronco?" Yes, it will be an issue.
2. "If it is not a problem can I use the flywheel ,pressure plate,clutch and bellhousing from the 170 c.i. mustang ?" No. Because it is a problem.
3. "My chassis has a stock 3 speed trans in it now. So in other words will it all bolt up? No. It won't.

You asked a VERY specific question about a very limited production engine and asked for a somewhat generic solution. The "early Mustang" with a 170 was only available for a few months in 1965. It used the C3DA-6394-B bell housing with a 132 tooth flywheel, a 3 bolt starter, and an 8.5 inch clutch coupled to the small 2.77 3 speed transmission. It has no provision for the clutch linkage. There is no bell housing that allows for direct bolt up to the Bronco 3.03 3 speed transmission. (Unless you source a C1UU-6394 bell from a 61-63 Econoline, and machine it to fit using the narrow holes in the late "butterfly" pattern 3.03)

FordSix.com is a decent website, but it leans heavily towards performance. It is also very Bronco-phobic.
The moderndriveline.com site has a detailed write up on the Ford Six bell housing difference. That article is about 90% correct. Actually, it is 100% correct for CARS, but 100% incorrect for Trucks. Which makes it about 90% correct in general, but totally wrong for Broncos.

You need a C6TA-7500-A bell housing for your Bronco. It will be cast iron, and have a threaded boss for your clutch pivot bracket. It will have a 2 bolt starter, and runs with a 136 tooth flywheel, and a 9 inch clutch. It will bolt directly to any 170 using the C6DE and later block. It will also bolt to the big pattern on the dual pattern 200 block.

And yes, this site is V8 centric. So most of us 6 cyl folks stay quiet. Because our fancy-smancy big brothers with V8's are so loud. But we will not be silenced forever.

 

[jamesroney]

Intermediate housing looks like thus:

https://shop.broncograveyard.com/Intermediate-Housing-manual-6-Cylinder/productinfo/11021/

It would help to get the spudshaft and dana 20 drive gear.

He said he has the 3 speed in the Chassis now, so pretty good chance he has that exact intermediate housing holding it all together...

 

[bmbm]

A six from a passenger car came with a front sump oil pan and the six for the Bronco came with a rear sump pan so you will need to find a rear sump pan for clearance with the front diff.

Or you could modify the oil pan to be a rear sump if you are handy with a welder. Have to alter the pickup tube as well.

 

[B RON CO]

Hi, when a guy says he has the tranny in the chassis I assume the tranny comes with the original bell housing. And we are in agreement that the large bell housing does not bolt up to the early blocks. The easiest thing for Cool67 to do is find a Bronco takeout 6. The hard part is finding the oil pan and pickup tube. Good luck

 

[Cool67]

Intermediate housing and bronco 3 speed trans is there …….nothing forward. Thanks

 

[B RON CO]

Hi, I would look for a complete 6 cylinder takeout drive line if you decide to stick with a 6 cylinder. Get everything in one place. You can put a parts wanted add right here. Good luck

 

[stout22]

If originality is not a concern, look for a 200. It's a much better design and has the same footprint as the 170.

 

[ntsqd]

If originality is not a concern, look for a 200. It's a much better design and has the same footprint as the 170.

I was about to suggest this.
Sounds like maybe there is no bell-housing in the Bronco at all. That could be a problem or it could be simple depending on what is found. The oil pan and it's pick-up tube at likely to be the bigger problem.

Better would be to go with the 250 ci six, but that was never offered in the Bronco, so it would be a definite step away from looking stock as well as a mixing and matching of various parts.

 

[bmc69]

I

Better would be to go with the 250 ci six, but that was never offered in the Bronco, so it would be a definite step away from looking stock as well as a mixing and matching of various parts.

One of my many EBs was repowered with a 250 many years ago. A '69 half cab. The 250 uses same bell housing as 289/302.

 

[bmbm]

I was about to suggest this.
Sounds like maybe there is no bell-housing in the Bronco at all. That could be a problem or it could be simple depending on what is found. The oil pan and it's pick-up tube at likely to be the bigger problem.

Better would be to go with the 250 ci six, but that was never offered in the Bronco, so it would be a definite step away from looking stock as well as a mixing and matching of various parts.

True for the 250 but to me it looks kind of stock under the hood, but the major advantage is the transmission selections available with the sbf bh on the 250 that can provide od gear which is a big leap forward in drivability and usefulness. Highway cruising is no problem in fifth od. And even my stock 250 provided more torque/power than I was expecting compared to the 200 it replaced. The only downside is to modify the oil pan to be rear sump unless you have a suspension lift.