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motor heads please translate

jtd123

Jr. Member
Joined
Jan 20, 2007
Messages
125
Loc.
merritt island
i had my original motor rebuilt and although i know its nothing fancy i was wondering what kind of horsepower you think i ended up with.

1975 302
edelbrock performer intake
edelbrock 600 carb
full length headers

here is the stuff that is chineese to me
.050" duration-204/214;cam lift-.280/.295;lobe center-107/117

they told me that it was an rv cam and they called it their stage 1 upgrade.i have a few other part #s if you need more info.i read somewhere that the different year motors had different horse power because of the emission stuff 1975 being one of the lowest but dont plan on having any of that hooked up.was the hp drop in different years because the heads were different?enough babbling what did i end up with?
 

broncnaz

Bronco Guru
Joined
May 22, 2003
Messages
24,341
Hard to say exactly but I'd estimate around 200hp at the flywheel. Thats still a fairly mild camshaft but is about right for a 4x4.

Yes the mid 70's engines were down on power not really due to emissions equipment though but more of a result of trying to lower emissions. from 73-76 302 blocks hard a .020 higher deck which helped reduce the compression and the pistons were dished there is a lot of conflicting info about heads I believe the broncos during those years had 64cc chambers again lowering compression. They also came with timing gear/chain sets that were retarded.
usually a simple timing gear/chain swap will wake up the engine. Good rebuilders will deck the block to the standard 302 height and gain you back a little compression. Most of the emission equipment only helps to lower emissions they usually dont affect power output other than the engines were tuned lean to help reduce emissions.
You have to be careful when comparing early 302s pre 72 or so with later 302's as the way HP was tested was different back in the day they only tested the engine with no acessories. later models had all acessories on and working during the tests. but power output was down in the later years.
 

mitzel

Contributor
Sr. Member
Joined
Feb 18, 2004
Messages
562
Loc.
Googleplex
I think broncnaz nailed it, I'm going with ~200HP too. That cam grind is the
ever popular Edelbrock Performer / Ford Motorsport A311 cam, pretty
much every cam company has a knock-off. Should be a great choice for
your engine.
 

jurob

Jr. Member
Joined
Oct 17, 2007
Messages
137
Loc.
Virginia Beach, Va
a motor rated less than 120hp...add a small cam, headers, intake and edelbrock carb....200hp, i don't think so.

if you want power, you've got the wrong combo. if it runs good, enjoy it.
 
OP
OP
J

jtd123

Jr. Member
Joined
Jan 20, 2007
Messages
125
Loc.
merritt island
everyone wants power few really need it.its a sunday dunkin dognutt driver for me i was just curious as to what it ended up at.thanks for your imput.
 

broncnaz

Bronco Guru
Joined
May 22, 2003
Messages
24,341
a motor rated less than 120hp...add a small cam, headers, intake and edelbrock carb....200hp, i don't think so.

if you want power, you've got the wrong combo. if it runs good, enjoy it.

75's were rated to have about 140HP not the lowest for a 302 the lowest was in 82 they were rated at 132 heck 78 351M's were rated at 132 also. These years of engine respond very well to straight up timing a decent cam and intake and exhuast mods 200HP or close to it is very easy to attain with his combonation. With a lot of these engines you can pick up 15 hp with more timing and a properly curved dist. If the pre 72 302 but out 205 without accessories and slightly higher compression theres no reason a later engine with a bigger cam and better exhuast/intake cant put out 200 with accessories.
 

recoiljunky

Bronco Guru
Joined
Jul 19, 2007
Messages
1,478
Loc.
Dothan, AL. USA
75's were rated to have about 140HP not the lowest for a 302 the lowest was in 82 they were rated at 132 heck 78 351M's were rated at 132 also. These years of engine respond very well to straight up timing a decent cam and intake and exhuast mods 200HP or close to it is very easy to attain with his combonation. With a lot of these engines you can pick up 15 hp with more timing and a properly curved dist. If the pre 72 302 but out 205 without accessories and slightly higher compression theres no reason a later engine with a bigger cam and better exhuast/intake cant put out 200 with accessories.

That's what I was thinking. Put another way, how hard do you think it would be to detune a 200 hp 302 back to 140 hp. Add a smaller cam, crappy carb, restricted exhaust, restricted intake, retard the timing, presto!
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,835
I will concure. 200 HP give or take 15% is a good guess. The only 2 things that would be hurting this engine from being a real good runner is a bit more compression and better flowing heads. But this engine should be happy running the cheapest gas you can fill the tank with.

That cam is the Edelbrock Performer cam (also sold by countless other companies). There is usually a slight hint of a performance engine at idle and runs good up through 5000 RPM. That 600 CFM carb is in theory a little large for the engine, it will be fine. I have ran bigger carbs and stocker engines without issues. That big carb will really add to the possible HP since it can breath at higher RPM better then a stock emissions 2 barrel could.

Now if you ecide to stick this on a chassis dyno, don't expect 200 HP. I will guess closer to 150 wiill be making it to the ground. But consider that you are putting more HP to the ground then the engine originally made at the crank in a package that is completely drivable, you are doing good indead.
 

Madgyver

Bronco Madman
Joined
Jul 30, 2001
Messages
14,678
Get a set of good aftermarket heads and pop in a Crower Baja Beast cam..
You'll be good to go....:cool:







Sorry, i just wanna stir up things....
 
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