BroncoII4x4.com

ok so before i get all kind of wise ass answers i just wanna say that im only askin for a guesstimate here. i was wondering how much horsepower my 89 bronco II is puttinn out. so heres what i got:

302 now 306
all new aftermarket rods, pistons
650cfm edelbrock 4v
mild street cam
long tube headers
true dual flowmaster super 40's with 2.5" pipe
2 10" pusher electric fans
E-3 plugs
k&n filter

now i know if i want an exact answer i would have to dyno it but im not doin that since its all lifted with mud tire and ect. ect.. i know im forgettin a few things but based on the above info it would be great if u guys could give me flywheel n rear wheel hp estimate. thanks a lot. ant

Dont know if it helps or not but my buddys 5.0 stang is puttin out about 325 at th wheels with a lil work done to it

You left out what kind of heads cast iron or aluminum? What are the intake and exhaust valve sizes? What is the cam lift and duration? What kind of intake are you using. and what does aftermarket pistons rods etc mean?

Now I am not trying to give you a hard time but what I am saying is that until you know info like that you can't make an accurate guess of what you are putting out.

My recommendation is to look up the book specifications on early ford 302 carburated engine. use a mustang or similar equipped car and use what they put in the book for a factory hi performance. You have a basically stock 302 with a mild cam and headers.

There are so many things that affect HP it is a hard one guess.

I am going to attach some info on the Hi performance 302 this was mainly 1968 stuff bur read away. We are NOT talking Boss 302.

In 1968 the small block Ford was stroked to 3.0 in (76.2 mm), giving a total displacement of 302 CI (4.942 L). The connecting rods were shortened to allow the use of the same pistons as the 289. It replaced the 289 early in the 1968 model year.
The most common form of this engine used a two-barrel carburetor, initially with 9.5:1 compression. It had hydraulic lifters and valves of 1.773 in (45 mm) (intake) and 1.442 in (36.6 mm) (exhaust), and was rated (SAE gross) at 220 hp (164 kW) @ 4600 rpm and 300 lb·ft (407 N·m) @ 2600 rpm. Optional was a four-barrel version rated at 250 hp (186 kW) @ 4800 rpm.

For 1968 only, a special high-performance version of the 302 was offered for the Shelby GT350[citation needed]. Its main features included an angled, high-rise aluminum or iron intake manifold, a larger Holley four-barrel carburetor, and bigger valves of 1.875 in (47.6 mm) intake and 1.6 in (41 mm) exhaust. It had a longer-duration camshaft, still with hydraulic lifters. The block was a high-strength, higher nickel content design made in Mexico. "Hecho en Mexico" casting marks are present in the lifter valley, and its main strength was the appearance of much larger and stronger two-bolt main bearing caps on the engine's bottom end. The heads had special close tolerance pushrod holes to guide the pushrods without rail rocker arms or stamped steel guide plates. The combustion chambers also featured a smaller quench design for a higher compression ratio and enhanced flow characteristics. Additionally, high flow cast exhaust manifolds similar to those on the 289 HiPO K-code engine further improved output. Heavy-duty connecting rods with high strength bolts and a nodular iron crankshaft were also included in this package. Rated power (SAE gross) was estimated at 315 hp (235 kW) @ 6000 rpm and 333 lb·ft (451 N·m) @ 3800 rpm. The package, which cost $692 (USD) including some other equipment, was not popular and did not return for 1969. This engine was not a factory engine. Rather, like all Shelby Mustang engines, it was modified by Shelby American in their capacity as a vehicle upfitter. This special engine is well documented in the Ford factory engine repair manual for 1968 Mustangs and Fairlanes. This engine block is considered the strongest production 302 block other than the Boss 302 and the Trans Am 302. It is considered to be on par and equal in strength to the K-code HP 289 block. The heavy duty Mexican 302 block was produced for several more years, and even showed up on Ford trucks and vans throughout the late 1970s and early 1980s.

I would guess your between 280 to 310hp. on a good day.

Mudhog1977 wrote:Dont know if it helps or not but my buddys 5.0 stang is puttin out about 325 at th wheels with a lil work done to it

sure it helps thanks. do u happen to know what kind of work he had done to it?

TO TEKATLARGE: i appreciate the response. truth is i really dont know what the valve sizes are, i know the heads are cast, and as far as cam lift n duration i dont know since i bought the truck like this. the motor by the way is a 89 or 90 im pretty sure. i wish i had more info but im the 3rd owner n the swap was done by the 1st. like u said on the valve sizes, is it a common thing for people to change or mess with for more hp or does it jus depend on what the factory size is? thx

The stock heads on the 5.0 have fairly small valves. I am thinking 1.7 or 1.8 for the intake valves and 1.6 for the exhaust. It is hard to get past that 300 HP mark with those small heads.

here is an example of a 351 I built for project Philstang.

1969 351W block. Forged crank. Stock rods and domed pistons. Aluminum heads with 2.02 intakes and 170 something exhaust. Edelbrock RPM Performer intake. Holley street avenger 670CFM A hydraulic lifter cam with a bit longer duration and more lift. Top that with a converted GM HEI distributor and stock Autolite Sparkplugs.
The engine mild loopy sound at Idle .

I took the completed engine down to a shop that had an engine dyno and we broke in the engine and ran it a bit before putting to work. I got 427HP and 406 ft Lbs of torque. The dyno sheet showed we could bump the timing and a minor re-jet and the figures would look even better but I decided to be conservative and put some miles on it before we squeezed it again. Unfortunately my Brother passed and his wife sold the car before we could put any miles on it.
We spent about 3500 to 4 thousand to build the engine and that is about average what you would spend doing the same thing having to buy the parts and machining.
Horsepower usually is the result of cubic dollars. My T coup is going to be running a 351 very similar to the one I just built. I got this crazy idea to put something real wild looking on the engine like dual 4's or maybe if I can find one maybe tri power. There is one other way I might go on the engine and that is to use the stock MPFI system. I like the consistency of the way an engine will run with fuel injection.

tekatlarge:

how big of a deal is it to change the size of the valves? n im sorry for ur loss btw

What ya need is to pick up a set of aluminum heads with the bigger valves. That will run you near a Grand. To try and make cast iron heads flow well enough to make the ponies you will spend close to that with machining and parts. Check out Ebay..

tekatlarge wrote:What ya need is to pick up a set of aluminum heads with the bigger valves. That will run you near a Grand. To try and make cast iron heads flow well enough to make the ponies you will spend close to that with machining and parts. Check out Ebay..

ok thanks ill have to check it out. what else do u think i cud do to my engine thats pretty cheap like a hundred or two? u no more than me so jus gimmi sum more ideas thx

play with this. get all the specs on your engine, otherwize its a guess. and if ya really wanna know,dyno it.you would be suprized about what you think you have for power and what you really have

http://rangerdave.freeforums.org/perfor ... -t447.html

need tado alot of work if you want 300hp at the wheels. i helped with this build

Honestly I dont know what all hes got done to it but my chin hit the ground when I saw it dyno'ed

what are the numbers

325 hp, and I think around 370 lbs torque cant remember torque exactly

dave the link for the toyfarm.org didnt work. i dont no why