302 and more power questions

[4x4livn]

Like said already... The 72 bronco 302 came 140 hp.. You should get a bronco graveyard catalogue, its got all the important info in the back..... Now for the fun, theres a list of upgrades you can do to raise hp without really sacrificing low end... Things like going to four barrel, however getting an after market manifold in itself will raise your hp. Get a master rebuild kit... Replace your cam with a good rv cam for some helpful low end, plus itll sound good. While your that deep change your pistons to flats... I had my heads professionally cleaned and had them shaved down a little which raised my compression... If your going more for hp. Go shorty headers, if you want a little more low end go long headers... And top it all off with a good exhaust system... And then for an extra couple hp. Put a fan clutch, or electric fan in... That will definatly get you way over 200 hp.....
I warn you though it gets expensive..... Im only half way with my engine rebuild, and i ve cleared 2000 dollars easy. So shop around find the best deals... And decide what you can or cant live with.... Good luck...

Oh trust me i understand the snowball that is a car project

There seems to be two schools of thought. One is build the powertrain and then build the rest of the vehicle. The second is to build your drivetrain and then build the powertrain around it. Why do i keep thinking about a Cummins in an Early Bronco... maybe the bronco just doesnt make enough noise for me

 

[4x4livn]

Cheapest way to get some serious power in the Bronco? Junkyard 351W - toss a carb'd 351W in there and you will be miles ahead of any 302 right from the start.

You aughta be able to find a running 351 for a few hundread and all of your stuff will swap over.

Any years in particular? Can the the motor be originally an efi motor? If i do buy one that was originally efi, i will try to get all the stuff to make it run. But I dont have the time to take on a complete engine and efi swap all at once... that damn job! So I would probably carb it for awhile just to keep it simple. This would make a really good winter project though. If its going to take $1500 to get a 302 to create the power I am after and a stock 351 will do it, i think you have a very valid point.

 

[4x4livn]

As stated before.

Carbed 351W and just about everything will swap from the 302. Would even look stock and other than Bronco nuts, no one else will know you swapped.

4.11 gears will make a huge change as well. 33" tires and you will enjoy the in town driving and highway too.

Would be night and day to stock set-up.

I need to do some more research into 351 swaps, but i thought you had to have a cowl induction hood to fit the air cleaner... is that not true?

 

[4x4livn]

Yeah I love my HD diesel (Brand X) and the 19.6mpg average sure keeps the love flowing....



Give time and money, anything is possible......LOL can't never could but you have to look at the practicality of doing it....and cost

Gears are cheap. Do this.....go get a cheap set of 4.11's (got mine for under $120) for the 9 and spend a day removing the stock gears and putting the new gears in. Give it a try....you will like what you get. If you don't you can pull them back out and sell them and only be out shipping if that.

Tim

I wish my 6.7L got that kind of mileage. Right now I am getting about 14-15 in the city and 18-19 on the freeway. The 33'' mud tires and the throttle down custom bumpers definitely brought down the mileage some.


If all I'm doing is going to 4.10s, why not buy a set of V6 axles? Honestly with my end goal of running 35s I was planning on 4.56s or 4.88s. I haven't run those gear sets through a calculator yet, that's just guessing what gears I would need. Someday I will put an overdrive trans in the Bronco, with that in mind which gears would you recommend for 35s?

 

[rguest3]

Sure you can use an EFI 351w. Would have a Roller block if '94+. I would get all that comes with it.

You would also have all the parts needed to convert to EFI later, however the upper truck EFI system would not clear at all. Use a BC adaptor on the 351w lower with a GT mustang upper intake and it should fit.

Initially, install the Edelbrock Performer intake, 600cfm carb and drop air cleaner (or stock 302 air cleaner) and it should drop right in. Can use the timing cover and fuel pump from your 302 for carb setup.

 

[rguest3]

Axles were the same if I6 or v8. Earlier fronts were Dana 30 and changed to Dana 44 in 71-72. All EBs had 9" rear axles.

With OD either gear would work well with the 35s.

 

[Timmy390]

If all I'm doing is going to 4.10s, why not buy a set of V6 axles? Honestly with my end goal of running 35s I was planning on 4.56s or 4.88s. I haven't run those gear sets through a calculator yet, that's just guessing what gears I would need. Someday I will put an overdrive trans in the Bronco, with that in mind which gears would you recommend for 35s?

All depends on who you plan to use the rig. If you plan on just a street rig with some mud and trails on the weekend now and then, I would stick to 33's and 4.11.

No real silver bullit answer to what you "need". If you want more power in the short term, re-gear. That's the cheapest way. If you re-gear later (go lower than the 4.11's) you can sell the 4.11's and get most of your money back then buy the lower set. win win.....

Tim

 

[KyleQ]

I need to do some more research into 351 swaps, but i thought you had to have a cowl induction hood to fit the air cleaner... is that not true?

It can be done with a drop air cleaner - there are quite a few of them on here, I didn't pay attention to that part as I went EFI immediatly.



I love the upgrades I did when I built mine, something to look into. F4TE roller 351W out of a van (for the cam) and GT-40 heads off a 96' Explorer. I used factory manifolds (have headers, later) and modified my 302 exhaust with a cut and some flex pipe and some clamps. I used Explorer fuel rail and injectors, 351W lower, B.C adapter and Mustang upper. Mustang EFI as well - 4.0 aluminum radiator and 5.0 fan with original 5.0 shroud.


Get a roller 351W motor and sell the EFI stuff if you want, you may want it later. Pull the EFI intakes off and put your carb intake on - verify flywheel imbalances and you can swap damn near everything from your old motor to the 351. Enjoy torque!

 

[Timmy390]

Axles were the same if I6 or v8. Earlier fronts were Dana 30 and changed to Dana 44 in 71-72. All EBs had 9" rear axles.

With OD either gear would work well with the 35s.

The I6's came with 4.11 or was it 4.10 gears stock.......

Tim

 

[4x4livn]

Sure you can use an EFI 351w. Would have a Roller block if '94+. I would get all that comes with it.

You would also have all the parts needed to convert to EFI later, however the upper truck EFI system would not clear at all. Use a BC adaptor on the 351w lower with a GT mustang upper intake and it should fit.

Initially, install the Edelbrock Performer intake, 600cfm carb and drop air cleaner (or stock 302 air cleaner) and it should drop right in. Can use the timing cover and fuel pump from your 302 for carb setup.

So i ideally i would like a 94 or newer 351 so that i get a roller block?

 

[Broncobowsher]

The I6's came with 4.11 or was it 4.10 gears stock.......

Tim

Rear was 4.09
D30 front was 4.10
D44 front was 4.11

That was the standard I6 gearing and optional V8 gearing.

4.10 gears as an option on the short stock tires was no problem when new. rolling on much larger tires it will bring it back into the relm of what stock gearing did on stock tires.

I ran 4.88 gears with 33s for years. Made several long distance road trips from Phoenix to Vegas. But the overdrive did help a lot. Tromp the skinny pedal, kick down into 1:1 and that gear sure made for some good passing! Especially when there are 2 semis you are passing when you thought you only had to get around 1 It is possible to do 100 MPH with 4.88 gears and no overdrive, just not recomended, on many levels.

Find a used 4.10 center section, drop it in. Now you have a spare center section to build at your leasure (and payment plan). This will also give you a chance to "test drive" the 4.10 gears. Do they work for you? do you want more?

As long as you don't use 4WD you can play with different gear ratios all you want. Doing a quick regear of the rear end gives you a chance to test drive the gearing options for as little cash as possible. Once you find what you like then build the axles.

 

[4x4livn]

It can be done with a drop air cleaner - there are quite a few of them on here, I didn't pay attention to that part as I went EFI immediatly.



I love the upgrades I did when I built mine, something to look into. F4TE roller 351W out of a van (for the cam) and GT-40 heads off a 96' Explorer. I used factory manifolds (have headers, later) and modified my 302 exhaust with a cut and some flex pipe and some clamps. I used Explorer fuel rail and injectors, 351W lower, B.C adapter and Mustang upper. Mustang EFI as well - 4.0 aluminum radiator and 5.0 fan with original 5.0 shroud.


Get a roller 351W motor and sell the EFI stuff if you want, you may want it later. Pull the EFI intakes off and put your carb intake on - verify flywheel imbalances and you can swap damn near everything from your old motor to the 351. Enjoy torque!

Definitely some good info! Thanks for the response.

 

[BIG_UGLY75]

Back to puting a diesel in, i had a friend who had a mustang from the same year as my bronco, for the longest we joked about puting a diesel in one of ours. I actualy thought i would. But he cracked his block, so decided to try it on his... We found an old dodge with with a turbo diesel, and after some serious modifying we got it to work... Bottom line it was fun, but we practicaly destroyed the front end... It had some serious low end power... We drove that shit like a year. The look on some guys face when we pull his silverado out the mud... Over all though, not worth it. We destroyrd what would have been a good collectable.but it was a lot of fun....

 

[4x4livn]

Back to puting a diesel in, i had a friend who had a mustang from the same year as my bronco, for the longest we joked about puting a diesel in one of ours. I actualy thought i would. But he cracked his block, so decided to try it on his... We found an old dodge with with a turbo diesel, and after some serious modifying we got it to work... Bottom line it was fun, but we practicaly destroyed the front end... It had some serious low end power... We drove that shit like a year. The look on some guys face when we pull his silverado out the mud... Over all though, not worth it. We destroyrd what would have been a good collectable.but it was a lot of fun....

No offense but you used the wrong motor and definitely did it to the wrong car. You used a very large 6 cylinder and shoved it into a muscle car... that is not easy to do. If I go that route I will be using a 4bt Cummins. Using this motor is heavily documented at 4btswaps.com, I have been doing research on their for years. You can essentially buy all of the parts needed for the swap in a giant kit. Im going to install one in a vehicle at some point. I just dont know if it will be the bronco, but making it fit would be the least of my concerns.

 

[BIG_UGLY75]

It was probably my funnest project, dont get me wrong it wasnt playin with the diesel, it was cutting into a good classic car. If i knew where to get an old pinto, or grimlen id definatly redo the same project...

 

[4x4livn]

It was probably my funnest project, dont get me wrong it wasnt playin with the diesel, it was cutting into a good classic car. If i knew where to get an old pinto, or grimlen id definatly redo the same project...

Got ya. The main reason for the diesel idea is, if i can get 20mpg driving this thing around town, i would make it my daily driver! What kind of mileage did that mustang get?

 

[matts460]

Car craft has a great artical on a stock roller motor 302 from the 80's and simply bolting on AFR alum heads and it made 400hp at the flywheel with good ftbs of torque too! the entire motor was stock exept heads,roller lifters,alum intake (dual plane) and sevral diffrent carbs and sizes were tested even with a 400cfm carb. You can simply google the carcraft 302 build artical it will pop up. Gives a good idea on how to build a strong 302 with out reving to the moon to do it.

 

[4x4livn]

Car craft has a great artical on a stock roller motor 302 from the 80's and simply bolting on AFR alum heads and it made 400hp at the flywheel with good ftbs of torque too! the entire motor was stock exept heads,roller lifters,alum intake (dual plane) and sevral diffrent carbs and sizes were tested even with a 400cfm carb. You can simply google the carcraft 302 build artical it will pop up. Gives a good idea on how to build a strong 302 with out reving to the moon to do it.

Sweet! I will definitely look into this!

 

[matts460]

I would also highly consider 4.11's or 4.57 gears too. Need to get power to the ground! I run 4.57 gears and mild built 302 and 31's its a c4 auto love how it runs and it cruises right along down the highway too and is not screaming at me! but i cruise between 60-65mph some folks may not be able to stand those speeds but im in no hurry to get out of my Bronco!

 

[4x4livn]

I would also highly consider 4.11's or 4.57 gears too. Need to get power to the ground! I run 4.57 gears and mild built 302 and 31's its a c4 auto love how it runs and it cruises right along down the highway too and is not screaming at me! but i cruise between 60-65mph some folks may not be able to stand those speeds but im in no hurry to get out of my Bronco!

Since the whole goal is build it once and be done, when i regear Im thinking 4.88s so i can run 35s. But I need to run all this through a gearing calculator before i make any decisions.