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What is the cheapest way to get 300 + hp out of a 302?

89K views 40 replies 23 participants last post by  v8only  
#1 ·

I am a new bee I have a 1967 mustang I am restoring this is my first project “I am pretty green” and my goal is to learn as much as I can, and do as much of the work myself I am not sure what year the engine is all I know it the guy I bought it from said it is a 302. what do you think would be the cheapest way to get 300 + hp out of it, the car has a Holley double pumper carburetor, a new hei distributer, wires, new plugs, eddelbrock intake, headers not sure of what kind,and that is all I know, what would you do?

Thank you
 
#3 ·
A 2bbl 302 and a c4 goes like pretty darn fast so why do you need more HP?

My first 66 coupe was set up like that.

That being said.

I would first ask what the suspension has to let the car safely run highway speeds.

From the tires on up to the steering wheel, if it is not right then all the HP in the world will only just make for a miserable car to drive.

The car already should be coming off the line pretty good and accelerate like a bat out of hell with the parts already hung on the engine. You can spend a lot of $$$ to get to more HP, do you really need it and can you really afford it.

My opinion is you should first make sure the rest of the car is right. If it does not have disc brakes then that would be a first project. If you are going to go fast you need to be able to stop.
 
#4 ·
I am a new bee I have a 1967 mustang I am restoring this is my first project “I am pretty green” and my goal is to learn as much as I can, and do as much of the work myself I am not sure what year the engine is all I know it the guy I bought it from said it is a 302. what do you think would be the cheapest way to get 300 + hp out of it, the car has a Holley double pumper carburetor, a new hei distributer, wires, new plugs, edelbrock intake, headers not sure of what kind,and that is all I know, what would you do?
OK, you already have some stuff you don't need, but what the heck.

A double pumper is overkill, especially if it's bigger than 600 cfm. What's the LIST number?

Which intake is it? You're probably OK either way, though.

The HEI isn't needed at all. Somebody waster their money.

You'll need a 600 cfm carb, Doesn't matter if it's a Holley, Edelbrock, or Summit. The Summit is the cheapest.

Use a nice hydraulic street cam, like the Ford C9OZ-6250-C. It's the hydraulic version of the 289 High Performance cam.

Port-match the heads to your exhaust, and use 289HP manifolds or headers.

Fella near here went with the C9OZ-C, 600 Edelbrock, learned how to port-match his own (really low performance) 67 iron heads, stock distributor with a good re-timing job, Performer RPM manifold, and headers. The engine turned 321 hp on the dyno.
 
#6 ·
The car is sitting on new front and rear suspension from mustang plus 1 inch sway bar in front new shocks and it has power steering 15x8" weld drag lites (came with it) I plan on converting to front disc brakes and keeping the drums in the rear, I know now the hei was a waste of money. The carb is a 600 cfm, I was told to work on the top end and I could get around the 300 mark. What do you guys think?
 
#10 ·
No offense, but the way most folks on a budget go about it is to make the best mods they can afford and stop when they run out of money. A better question might be, what's the most streetable bang-for-the-buck I can get out of $3,000, or words that effect. Asking for the cheapest way to 300hp is a bit like asking for the cheapest way to build a 4000 sq foot house...
 
#9 ·
AFR 185 heads is all you need..............of course it goes without saying, a single plane intake and Holley 4bbl.
 
#13 ·
Besides the budget or bang for the buck IMO what use is expected from the engine. Do you want an impressive sounding rump a rump peaky engine or do you want a smooth tractable daily driving car. Each may have 300 peak HP but a much different performer.
 
#19 ·
comp cams 260 or 268 cam, 5 angle valve job, headers, wieand 8124 intake and a 525 road demon carb, will get you around 275hp. The best way is to yank the 302 and throw in a 5.0 HO from a mustang gt with the roller cam and just add some TW heads or afr 165's and the above(int, carb, headers) you will have more than 300hp with great low end TQ and fuel economy.
 
#22 ·
You need to check out the link posted by Lemonshindig Budget 300HP 302 Build. It was written by Jim Woods who owns Fordstrokers. He knows his stuff; he builds engines for a living, and high quality ones at that. His build gives you a baseline of parts with the dyno results and other options to increase your hp level if you want. It was a good write up. For $2000 he built a complete engine that made what you are looking at making with a small camshaft.

300hp is not hard to get to with a 302 as was shown in Jim's build.
 
#24 ·
You want smooth, driveable and power? Two words - cubic inches. Stroke that 302 to a 347 and keep all the components middle of the road (not too wild).

IMO it is no good to have a motor that makes 400 hp at 7000 rpm and has nothing below 2500. That is just not driveable in my opinion.
 
#25 ·
If he wants to stroke it..........{Bevis ad Butthead laugh } he should really think about a 351w and do the "poor mans stroker" which is a Scat crank, with stock 351w rods, and stock 302 pistons...........393w.
 
#26 ·
I'm sorry but 1hp per cubic inch is not some wild engine. There is absolutely no need for him to stroke his engine to reach that hp level and keep it "streetable". A stroker kit would be money down the drain that he would not need to spend. He would be much better off putting that money into a good set of heads then a stroker kit.
 
#27 · (Edited)
Hey I was just thowing out other idea's. He asked, "Does anyone have any other ideas?"

I've already mentioned the heads, and I think that is the best way to go. However I'm just giving him another thing to think about.

More cubic inches would mean a less aggressive cam, and better street manners over another engine of less displacement making the same HP.

Also, low end torque will be better for off line acceleration vs a smaller displacement engine.

The 393 is one of the cheapest stroker engines you can build since you don't need to buy after market rods or pistons {unless, like me, you are going to be making more hp/tq}.

As for the cost factor, he could sell his current setup {I have done this many times} buy a junked 351w, a basic rebuild kit, and the stroker crank, his choice of heads {the Corral usually has heads for sale most of the time on that forum} iron, or aluminum, used 4bbl intake.

Of course that would all depend on what he could buy a used engine, and what he could get for his old engine......

Anyway, just another idea to keep him awake at night.........lol.
 
#28 ·
Run a compression and leakdown test on the current engine and get back to us with the numbers. Also, if available, run the car across a chassis dyno and get some current rwhp numbers.

By 'cheap', I'm assuming you mean to keep the engine in the car with minimal intrusions and use the maximum amount of existing parts.

Get me the list number of the carb, the make and model of intake and the make and type of headers and configuration of the exhaust system.
 
#29 ·
This post caused good discussion. Is cheap same as best value? Is a 300 hp engine that lasts a couple weeks a cheap investment? Point is, not mine but implied in responses is on any project definition is needed.
 
#32 ·
lol like everyone else, I too chose to build the snot out of the drivetrain first. I'm running a low 13/high 12 second combo behind 4 wheel drum brakes too.

Needless to say, I'm scared everytime I drive it, and my drum brakes are in great shape for their age....it just doesn't stop all that motor in time if you lay the throttle down then need to stop in a hurry....end of the 1/4 mile is fun too...I just downshift my way to the lowerspeeds and take the last turnoff.

However, i'm about to put it down for some down time next week...late model 13" cobra brakes up front, 373 explorer rear with disc brakes out back, shelby drop and a few other things....all the things I should have done before the motor.