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71 Bronco 302 engine specs????

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  #1  
Old 09-13-2018, 10:02 PM
LoneRanger302
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71 Bronco 302 engine specs????

Hello, newbie to the forums here, long time Ford fan and enthusiast!
I am about to acquire a 1984 Ford Ranger and a 1971 Ford 302 v8 out of a 1971 Bronco.

plans are to marry the two once i round up all the parts, bells, and whistles i want to use to build the motor.........but first, i want to get more familiar with what i am working with in the first place.

does anyone have all the stock info for this motor? I dont have casting numbers yet, but is there any kind of general info/general knowledge out there of the following?:

what size (bbl count and cfm) carburetor did this engine come with typically?
what is the stock compression ratio?
what are the head specs? (Int/exh runner size, chamber size in cc's, valve diameters, etc)
what are the stock camshaft specs?
does this motor have forged internals?

and what would i have to do to get GT40 heads to fit this motor? Or is it not possible due to differences?

thanks all!
 
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  #2  
Old 09-14-2018, 10:23 AM
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as a 'ford man' U know just bout anything of the era could B there.
Next
because it's 47 y/o U don't know what's been swapped in.
I'd suggest patients'n a positive ID - once U have it.
That doesn't mean U can sit back. U can do some wrk now on researching where all the castings'n stampings might B on the motor (for heads v block v exh. mani, etc) unless U know all that now.

" ...marry the two..."
What vehicle will U end up with?

W E L C O M E !!!
to the site (ONE of the best on the forum).
U may wanna hook up w/ur local chapter, I found alot of enjoyment w/mine.
Congrats on ur recient purchase - a 302 Ranger ( if 4WD I'd put in a built C4'n call it done). Might visit the ranger station dot com.
Since ur in the bronk forum I'd ***-u-me U got 1 and may B settin up for that. An efi 4.9 is a good choice 4 that depending on final application (wrk, rec, st, strip, show, etc). Let us know that application (80% of driving conditions, 80% of RPMs)) and may B geographic location (not in sig)...
Good Luck
Keep Talkin
 
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Old 09-14-2018, 03:26 PM
LoneRanger302
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Originally Posted by chrlsful View Post
as a 'ford man' U know just bout anything of the era could B there.
Next
because it's 47 y/o U don't know what's been swapped in.
i suppose youre right, they could have put a cam in it or something. Seems pretty stock though.

Originally Posted by chrlsful View Post
I'd suggest patients'n a positive ID - once U have it.
That doesn't mean U can sit back. U can do some wrk now on researching where all the castings'n stampings might B on the motor (for heads v block v exh. mani, etc) unless U know all that now.
i will check into where i can find the casting and stampings on the motor.
Really im just looking for specs on the 1971 302 is all.

Originally Posted by chrlsful View Post
" ...marry the two..."
What vehicle will U end up with?
i will end up with the 302 in the 1984 Ranger. Sorry if that makes you cringe. I think the donor Bronco is long gone. As a side note: i LOVE the 70s Broncos.

Originally Posted by chrlsful View Post
W E L C O M E !!!
to the site (ONE of the best on the forum).
U may wanna hook up w/ur local chapter, I found alot of enjoyment w/mine.
I will have to check that out, thank you!!!


Originally Posted by chrlsful View Post
Congrats on ur recient purchase - a 302 Ranger ( if 4WD I'd put in a built C4'n call it done). Might visit the ranger station dot com.
The Ranger is currently a 2.8L v6.....going to be swapping in the 302. It is 2WD. I would do the 4WD swap (maybe in the future) but for now i am going to just keep it simple and keep it 2WD with a manual trans.

Originally Posted by chrlsful View Post
Since ur in the bronk forum I'd ***-u-me U got 1 and may B settin up for that. An efi 4.9 is a good choice 4 that depending on final application (wrk, rec, st, strip, show, etc). Let us know that application (80% of driving conditions, 80% of RPMs)) and may B geographic location (not in sig)...
Good Luck
Keep Talkin
Nope, i wish i had one but i do not have a Bronco. Just the engine from one.

as for driving conditions....lots of hills and winding roads, im in Southern Indiana. The new setup will need to have a lot of torque and the rpms most of the time probably wont be that high (2500-3500?) although i would like to take the engine to 85-90% of its RPM limit (5000-5800?)....i dont know at what point these old 302s will scatter but i definitely dont want to do that, but i do want to have some fun, do donuts, burnouts...etc etc.

i plan on daily driving the truck, and maybe enter it in a car show here and there. I dont see myself taking it to the drag strip, there isnt one very close to me.

 
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  #4  
Old 09-14-2018, 05:31 PM
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lotta 302 / 5 ohs over on RangerStation.com...
They can give U some pointers, other considerations (big weight change inda nose).
Ex buddy here did this w/a sm lift (15/16 inch tires now) & C4 ('ex' B cuz I think he stole my 'pan fill'
C4 oil pan frm the '77 bronco 302 I had in the back 40 to use for prts 4 my own rig.
It's a bronk specific prt - a lill harder to find.)

"...they could have put a cam in it or something..."
didn't mean that. Ford is not like che**y. Motors run cross models.

https://www.ford-trucks.com/forums/forum122/
talk (post) to
Koestner
good ppl over there!
 
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Old 09-14-2018, 06:09 PM
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Originally Posted by LoneRanger302 View Post
what size (bbl count and cfm) carburetor did this engine come with typically?
500cfm I believe. These were available with both 2bbl and 4bbl carbs but trucks and passenger cars mostly saw 2bbl versions. The 4bbl versions were found in Mustangs and such. Stock 2bbl engine made 220hp net.
Originally Posted by LoneRanger302 View Post
what is the stock compression ratio?
9.5:1
Originally Posted by LoneRanger302 View Post
what are the head specs? (Int/exh runner size, chamber size in cc's, valve diameters, etc)
2bbl heads are pretty lame, 58cc chambers, 1.78"/1.45" valves, really small ports. Even with a big cam this head won't make more than 260-270hp,
Originally Posted by LoneRanger302 View Post
what are the stock camshaft specs?
Again pretty small, Ford has always been very conservative with cam specs even restrictive at times. A big stock cam would be in the 260deg range seat to seat with a hair over 0.400" lift, a small cam 240 deg with 0.380" lift.
Originally Posted by LoneRanger302 View Post
does this motor have forged internals?
No.
Originally Posted by LoneRanger302 View Post
and what would i have to do to get GT40 heads to fit this motor?
Bolt them on, some versions may require head bolts with shoulders, they are a great upgrade that flow at least 25% better.
 
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  #6  
Old 09-15-2018, 02:52 AM
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Originally Posted by chrlsful View Post
lotta 302 / 5 ohs over on RangerStation.com...
They can give U some pointers, other considerations (big weight change inda nose).
Thank you for the suggestions! And yeah ive thought about the weigh distribution thing, thought about how i might counteract that. Not sure yet.

Originally Posted by chrlsful View Post
Ex buddy here did this w/a sm lift (15/16 inch tires now) & C4 ('ex' B cuz I think he stole my 'pan fill'
C4 oil pan frm the '77 bronco 302 I had in the back 40 to use for prts 4 my own rig.
It's a bronk specific prt - a lill harder to find.)
i see. Im sorry to hear about your friend.


Originally Posted by chrlsful View Post
"...they could have put a cam in it or something..."
didn't mean that. Ford is not like che**y. Motors run cross models.
AH, ok i know what you are talking about.
[
QUOTE=chrlsful;18195375]
https://www.ford-trucks.com/forums/forum122/
talk (post) to
Koestner
good ppl over there![/QUOTE]

ill check that out! Thanks again for your help!
 
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  #7  
Old 09-15-2018, 06:23 AM
LoneRanger302
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Originally Posted by Conanski View Post
500cfm I believe. These were available with both 2bbl and 4bbl carbs but trucks and passenger cars mostly saw 2bbl versions. The 4bbl versions were found in Mustangs and such. Stock 2bbl engine made 220hp net.
Ok. Thats more than i was expecting. From my calculations and what i wanna do i was estimating on needing a 570cfm 4bbl but if that is the case i may need to go 600, 625, or 650. Ill hafta do more research on how much i will need for my build.

Originally Posted by Conanski View Post
9.5:1
Thats actually less than i thought. From reading around i thought it was 10:1. But 9.5:1 is ok. It may be different once i put different heads on.

Originally Posted by Conanski View Post
2bbl heads are pretty lame, 58cc chambers, 1.78"/1.45" valves, really small ports. Even with a big cam this head won't make more than 260-270hp,
i figured they were lame, i hate to pull apart something that was meant to go together, but im in search of hp and torque and clearly those heads wont get me there.

Originally Posted by Conanski View Post
Again pretty small, Ford has always been very conservative with cam specs even restrictive at times. A big stock cam would be in the 260deg range seat to seat with a hair over 0.400" lift, a small cam 240 deg with 0.380" lift.
thank you! I was just curious as to where it starts, so i have a reference point. So is it likely the latter?

Originally Posted by Conanski View Post
No.
thanks!

Originally Posted by Conanski View Post
Bolt them on, some versions may require head bolts with shoulders, they are a great upgrade that flow at least 25% better.
sweeeeet. Looks like i need to make a trip to the junk yard. I dont feel like spending $1000 on heads that do the same thing as junk yard heads. Been reading some articles with people making the hp and torque i want to make very easily with those heads, upgraded valves and springs, and a bigger cam (272/280, lots of lift).
 
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Old 09-15-2018, 10:44 AM
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What will the actual application be?
% on v off rd?, type of trail?, mudder?, geographic location (did U say Iowa?)?
 
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Old 09-15-2018, 02:36 PM
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Originally Posted by chrlsful View Post
What will the actual application be?
% on v off rd?, type of trail?, mudder?, geographic location (did U say Iowa?)?
actual application is a 1984 Ford Ranger.
The only Bronco parts will be the short block for the most part.

probably no off road for now. Im in southern Indiana.
 
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Old 09-15-2018, 03:40 PM
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sounds like:
a DD on
2 lane black top with
some steep short hills,
10% interstate -
then?
 
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Old 09-15-2018, 09:31 PM
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Originally Posted by chrlsful View Post
sounds like:
a DD on
2 lane black top with
some steep short hills,
10% interstate -
then?
some steeper and sometimes longer hills than you would think, and the only way to get anywhere substantial (closest major cities both an hour away) you have to take the highway, yes.

surprisingly, there really arent any 4x4 parks close, that i know of yet. The truck isnt 4x4 to begin with, so i feel like a swap would be an undertaking and right now i just want to focus on getting the power plant right before i decide anything like that.

 
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Old 09-15-2018, 09:41 PM
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Hey,
U know the rear gear?
I'm not that familiar w/them - has a mazda 5 speed?
 
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