Too Much Info!

[Explorer]

Ok guy's I'm overwelmed. More tech info than my brain can compute. Got a 66 Half cab Bronco with 4.11 gears, manual tranny. Want to rebuild and up the torque/horsepower on a 200 I6. It's going to be a 90% street driver. All the build info I find is for cars, with higher gear ratio's. Someone steer me in the right direction. The Bronco section had last post in April so I doubt I'll get any info there any time soon.

 

[82F100]

Explorer, the same basic upgrades would apply. The Classic Inlines 264 cams are a good choice for all around street ability or even look at Comp Cams Extreme energy grinds like the 252 or 262 grind. Another possibilty is having them put one of their small block ford offroad profiles on a 6 cam. ( I know it's a v-8 grind) but it's more of a bottom to mid range cam.

 

[Lazy JW]

....... Got a 66 Half cab Bronco with 4.11 gears, manual tranny..

8)

4.11 gears will actually want an engine combo that can wind up pretty fast. As mentioned above, all of the normal hotrodding rules apply; get that thing to BREATHE! Don't know what your budget allows but this is a perfect application for one of those new aluminum heads from Classic Inlines

If you don't already have The Falcon Performance Book then you should get one.
Have fun,
Joe

 

[Explorer]

I'm starting to get an understanding on this. I'm a little old, but have a fast learning curve. Can't quite justify the aluminum head, but will go with the 2bbl./ headers/cam and head work. May change my mind when I get a price on reworking the head. Would like to run about 9/9.5 CR I have a auto parts store/machine shop only 2 miles away that I trust so that helps. Going up to talk to him this morning and hope to pull the engine today. Pulled the body Tue. so things should go a lot easier. I'm going ground up on this build. My main concern is the power curve w/4:11's having enough power left at 65mph to still pull hills, I don't live in flat land, and this one I plan on keeping for myself. Thanks guy's, keep the suggestions coming.

 

['68falconohio]

I highly recommend a direct mount 2V conversion if you stay with the log head. I got a later model log head from a junkyard because my C8 head was cracked in 3 places. The D7 log head I got has larger intake valves, intake runners, hardened exhaust valve seats, and a higher volume 'log'. Although there is a GREAT performance difference between a stock head and my modified head..I really wish I would have had the extra money to build a CI alum. head and do it the best way available. I have finally reached the point where I have more power than my $35 Walmart tires will handle. :mrgreen: :mrgreen:

I noticed a difference on the casting where my C8 head was cracked in comparison to my D7 head. There's more meat on the D7 head around all of the exhaust valve guides. My C8 head cracked from one of the siamesed valve guides to it's corresponding pushrod hole. Along with a crack in the top of the intake log. And another crack through an exhaust manifold mounting ear.

I'd imagine that a lot of them cracked between the guide and the pushrod hole and that's why Ford changed the design. Get the head magnafluxed/magnetic particle tested before you start dumping money into it.

Stephen

 

[rocklord]

If you're going to a 2Bbl conversion and doing head work, now would be the time to find a late model head with the larger valves and mill the log intake for a direct 2Bbl bolt on. That along with a header, upgraded cam, and Duraspark or DUI ignition would be the best, and relatively inexpensive, way to go for the performance you're looking for.

I agree with Lazy JW, purchase the Falcon Performance Handbook; this handbook will help you immensely. Don't get caught up with it saying "Falcon"; the small block six is referred to as the Falcon six since that's where it started life. It can be found in Falcons, Comets, Mustangs, Mavericks, Fairmonts, Granadas, and some Capris (80-82).

Don't worry about the Bronco section here not being updated since April; the engine is what this forum is about. I'm sure you can find out information specifically for your Bronco on Bronco forums, but they are probably light on talk about your engine. They'll tell you to pull out the six and install a V8; the same thing goes for me on the Mustang forums. Everybody does that, only the most avid will keep the six and upgrade it.

There is a great group of people on this site willing to help. Just keep asking questions, they'll be answered.

Have fun!

 

[rocklord]

Is this the EB you bought from Maknwakes advertised on the classicbroncos.com forum? Not a bad price if so.

That forum is just like the Mustang sites I'm a member of; V8! V8! V8!
"You have a six cylinder. When you gonna swap it out for a V8?

 

[Explorer]

Yea, it's the third one I've bought from him so I get a discount. Finally talked him into the top which is darn near mint. It's a whole lot better than the pic's showed. The cowl, windshield frame, doors, and the whole inside from bulkhead back are rust free except for one rear floor corner plate ($28). It helps when he's only 20 minutes away.

 

[82F100]

My next question would be what size tires are you plannin on runnin? You might also consider swapping to 3.73's or 3.55's for more streetable gears.

 

[Explorer]

235/75/15's That what I'm running on my 76 Explorer.

 

[bmbm40]

Hope this helps.
I had a 200 in my 66 Bronco with 4:11 gears and 235 75 15 tires. I live about 4300 ft elevation and pulling the grade up to tahoe required downshift to 2nd about half way up which means going about 35. I never felt like driving much faster than about 55 because the engine was revving pretty fast. I put on 30 9.50 15 tires and I could cruise faster but still slow up hills. Part of the problem is the 3 speed trans. So I put in a 250 six out of a 1970 Mustang and NV3550 5 speed trans from a 04 jeep Wrangler. All this cost about $2000. I paid a $100 for the used engine and the rest was for the trans. adaptors, flywheel, Centerforce clutch and plate, throwout bearing and misc. I figured this is about what a rebuild on my 200 would have cost including cam, header, modified head and everything else. After all this I would still have the limiting 3 sp trans. The five speed trans changed the whole feel of the Bronco and the ratios are perfect. I also added power steering and front disc brakes so that added alot to the change factor. Even with the used engine and my $35 dollar picnpull DSII , everything else stock and original carb etc, this made a big difference. The 250 is more of a Bronco engine in my opinion based on experience. The 200 was a great engine that wanted to rev easily but the 250 has more torque that you can feel. The best part about all this is I still get to do the performance mods to the 250. This was a big job, very time consuming and sometimes frustrating but worth it to me. Good luck with your Bronco and check out classicbroncos.com.

 

[Explorer]

My next question would be what size tires are you plannin on runnin? You might also consider swapping to 3.73's or 3.55's for more streetable gears.

Answered the tire question, but I had considered swapping out the running gear to a Dana 44 and big bearing 9" w/3.50 gears that I have access to. I would gain front disc brakes with that setup but was afraid the gearing would kill the low end. The 66 3 speed does have 3.41 first gear/1.86 second, a little lower than later models. Opinion?

 

[Lazy JW]

The early Bronco was designed to compete with the Jeeps and Scouts of that era; in other words low-speed light four wheel drive vehicles intended for utility use knocking around the ranch, etc. Small engines and low gears were considered adequate for the task, but were never designed for high-speed freeway type driving.

Asking a small engine to pull oversize tires or tall gearing will end in frustration as you need the torque multiplication of the low overall ratio to make up for the lack of engine torque.

That 200 is gonna need to rev up to get 'er done. A 250 with its 25% increase in displacement makes a lot of sense, but there is a large cost involved.

If you plan to keep the original engine and tranny then figure on spending some time in 2nd gear at high rpm.
Joe

 

[bmbm40]

If disc brakes is your goal just do the chevy disc brake conversion like I did on my Dana 30. Total cost was about $200 with used parts from picnpull. Get the parts list from classicbroncos.com.
There is no easy way to go with the trans that I could find. The 250 has the small block ford bell housing pattern so you have more choices for trans swaps. In the falcon manual they talk about some four speed top loader trans and t5 trans for 200/250 engines. I found out that Advanced Adapters is planning an adapter to install ax15 trannies for broncos. These might be cheaper than a nv 3550.

 

[Explorer]

The disc brakes would just be a freebe. Main goal is not having a 50mph top end. I put power assist drum on one of my Bronco's and it stops better than the disc brakes on my 76. Looking like I better stay with my 4:11's.