1984 Bronco build thread

[StraightSix]

Yep, that would be the one. Thanks Gary! with any luck I can find the few missing parts I need and get this going fairly quickly.

Well, I had a productive lunch break. First, something caught my eye from the bottom of the parts pile..

the cold air duct is the original from my factory intake set up. I hadnt seen it in a while so I assumed it was gone.. Score! The air cleaner is off of my junkyard 82 block. it just so happened to have a seemingly ok cold weather modulator in it. I have two reasonable looking bimetallic sensors now. I still dont have a good vacuum motor to control the damper, but the list is getting shorter.

I took some better photos of the options for arranging the air cleaner. there are two options that will clear the heater core box.

option 1 - original snorkel pointed to the firewall.

Benefits - This orientation allows me to eliminate the 3/4" air cleaner spacer that goes between the carb and the intake. the air cleaner could sit directly on the carb. the new snorkel location would be over the original PCV location so I wouldnt need to patch the PCV hole closed.

anti-benefits - the Cold weather modulator is in the back far from my vacuum source (base flange of the carb, driver front). it seems like it would make getting the lower portion of the air cleaner off a bit of a pain.

option 2 - original snorkel pointed towards driver side head light

benefits - vacuum modulator is in a very convenient location.

anti-benefits - the 3/4" spacer is required between the carb and the air cleaner to prevent interference between the air cleaner and the heater core box.

assuming I dont take the whole thing apart 5-10 per week, Id prefer option one. I think it will look cleaner. I sure do take it apart a lot these days though.. Input is welcome.

option 3 - use the orientation from option #1 (original snorkel points to fire wall) and make a new hole for the cold weather modulator if it really bothers me that much.

[Gary Lewis]

Well, I had a productive lunch break. First, something caught my eye from the bottom of the parts pile..

the cold air duct is the original from my factory intake set up. I hadnt seen it in a while so I assumed it was gone.. Score! The air cleaner is off of my junkyard 82 block. it just so happened to have a seemingly ok cold weather modulator in it. I have two reasonable looking bimetallic sensors now. I still dont have a good vacuum motor to control the damper, but the list is getting shorter.

I took some better photos of the options for arranging the air cleaner. there are two options that will clear the heater core box.

option 1 - original snorkel pointed to the firewall.

Benefits - This orientation allows me to eliminate the 3/4" air cleaner spacer that goes between the carb and the intake. the air cleaner could sit directly on the carb. the new snorkel location would be over the original PCV location so I wouldnt need to patch the PCV hole closed.

anti-benefits - the Cold weather modulator is in the back far from my vacuum source (base flange of the carb, driver front). it seems like it would make getting the lower portion of the air cleaner off a bit of a pain.

option 2 - original snorkel pointed towards driver side head light

benefits - vacuum modulator is in a very convenient location.

anti-benefits - the 3/4" spacer is required between the carb and the air cleaner to prevent interference between the air cleaner and the heater core box.

assuming I dont take the whole thing apart 5-10 per week, Id prefer option one. I think it will look cleaner. I sure do take it apart a lot these days though.. Input is welcome.

option 3 - use the orientation from option #1 (original snorkel points to fire wall) and make a new hole for the cold weather modulator if it really bothers me that much.

I like option 2 better. I think you could put a short snorkel on and get to the cold air opening in the radiator support from there with the hose - assuming there’s an opening on the driver’s side. That way you wouldn’t have to cut a new opening.

[StraightSix]

I like option 2 better. I think you could put a short snorkel on and get to the cold air opening in the radiator support from there with the hose - assuming there’s an opening on the driver’s side. That way you wouldn’t have to cut a new opening.

Gary,

I hadnt considered using the original snorkel and running to the air inlet on the driver side (I do have the cutout with pre drilled holes). If my only goal was a cold air intake, that would be by far the fastest and easiest thing I could do. I do think it would make accomplishing hot air/ thermostatically controlled air temp pretty difficult as the snorkel would be right over the valve cover, or on the driver side of the block far away from the exhaust manifolds.

as silly as it may sound to our more northern members, I do think I want functioning hot air. we pretty reliably have a few days a year with day time temps in the low 20s and it may be driven many many miles per year in ambient temps below freezing. I dont want it to be a fair weather only vehicle. since the penalty for too cold air is risk of lean out and detonation, I dont want to forgo the opportunity to have hot air. also, its pretty cold natured at start up. it could use some help in that department

[Gary Lewis]

Gary,

I hadnt considered using the original snorkel and running to the air inlet on the driver side (I do have the cutout with pre drilled holes). If my only goal was a cold air intake, that would be by far the fastest and easiest thing I could do. I do think it would make accomplishing hot air/ thermostatically controlled air temp pretty difficult as the snorkel would be right over the valve cover, or on the driver side of the block far away from the exhaust manifolds.

as silly as it may sound to our more northern members, I do think I want functioning hot air. we pretty reliably have a few days a year with day time temps in the low 20s and it may be driven many many miles per year in ambient temps below freezing. I dont want it to be a fair weather only vehicle. since the penalty for too cold air is risk of lean out and detonation, I dont want to forgo the opportunity to have hot air. also, its pretty cold natured at start up. it could use some help in that department

Good point, I forgot about the heat issue.

So you could do it right and go the other way. Or do it quick and dirty for now and plumb up the cold for the summer. Me, I'd do it right.

[StraightSix]

Good point, I forgot about the heat issue.

So you could do it right and go the other way. Or do it quick and dirty for now and plumb up the cold for the summer. Me, I'd do it right.

Ive got atleast a few weeks before it gets hot and maybe two months before it gets really hot. getting just the cold air side working with option 1 or 3 is probably a one day project assuming I have everything I need handy. I dont really even have to get the vacuum modulator, vacuum motor, bimetallic sensor, or hot air stove figured out for quite a while. for now, laying the foundation in fab work is probably a good start.

its just about always easier and faster to do it right the first time.

[Gary Lewis]

Ive got atleast a few weeks before it gets hot and maybe two months before it gets really hot. getting just the cold air side working with option 1 or 3 is probably a one day project assuming I have everything I need handy. I dont really even have to get the vacuum modulator, vacuum motor, bimetallic sensor, or hot air stove figured out for quite a while. for now, laying the foundation in fab work is probably a good start.

its just about always easier and faster to do it right the first time.

I agree it is "just about always" better to do it right the first time. And if you have the time to do it that way now then you'll save time in the long run.

But it would be easy to get cold air to it the "quick and dirty" way.

[StraightSix]

I agree it is "just about always" better to do it right the first time. And if you have the time to do it that way now then you'll save time in the long run.

But it would be easy to get cold air to it the "quick and dirty" way.

Here is what I was able to get done in about an hour this evening. I have a usable example of both sensors, the 84' 300 intake snorkel (with busted vacuum motor) and a stripped upper and lower 302 air cleaner. I marked the new location for the snorkel on the air cleaner with a marker. Ofcourse, thats the outside profile, not the actual line to be cut on.

I still need to cut out the spot for the new snorkel and patch the old snorkel hole. I need a few extra short 1/4 bolts for the attachments. After drilling out a few rivets, I see why you used bolt Gary. I think I may expirement with some kind of foam product to help seal off the snorkel holes. Im not sure if Ill get away with bending a lip to fit inside of the snorkel the way the factory spot works, but I guess I can try and cut it off later if it doesnt work out.

Once the cutting and patching is done Ill put it all together to verify fit then take it all apart and get everything truly clean. Then paint, then final assembly.

[Gary Lewis]

Here is what I was able to get done in about an hour this evening. I have a usable example of both sensors, the 84' 300 intake snorkel (with busted vacuum motor) and a stripped upper and lower 302 air cleaner. I marked the new location for the snorkel on the air cleaner with a marker. Ofcourse, thats the outside profile, not the actual line to be cut on.

I still need to cut out the spot for the new snorkel and patch the old snorkel hole. I need a few extra short 1/4 bolts for the attachments. After drilling out a few rivets, I see why you used bolt Gary. I think I may expirement with some kind of foam product to help seal off the snorkel holes. Im not sure if Ill get away with bending a lip to fit inside of the snorkel the way the factory spot works, but I guess I can try and cut it off later if it doesnt work out.

Once the cutting and patching is done Ill put it all together to verify fit then take it all apart and get everything truly clean. Then paint, then final assembly.

Good luck. That aluminum is not very fun to work with as it is brittle. I did the cutting on a steel lower and it wasn't bad.

And use washers on the inside to spread the load. With the vibrations of the six I'm guessing the bottom will crack pretty quickly if you don't. They cracked pretty easily on the V8's, so...

[StraightSix]

Good luck. That aluminum is not very fun to work with as it is brittle. I did the cutting on a steel lower and it wasn't bad.

And use washers on the inside to spread the load. With the vibrations of the six I'm guessing the bottom will crack pretty quickly if you don't. They cracked pretty easily on the V8's, so...

Good advice on the washers for sure.

My lower section is magnetic. Go figure. Does this perhaps mean it isn't original to a 302?

[Gary Lewis]

Good advice on the washers for sure.

My lower section is magnetic. Go figure. Does this perhaps mean it isn't original to a 302?

Interesting! It is doubtful it was original on a truck. Only the 351HO and 460 air cleaners had steel bottoms from what I’ve seen. But there was a smaller Mustang air cleaner that had a steel bottom.