stoker kit advise

[bama_rebel_63]

hey i have a 1971 mustang an i has the original 302 in it but i want more power i was thinkin of strokin the engine and upgrade it to a 347... so i have 2 questions 1.How much horsepower would i have now? 2.is the 347 even a good idea or should i go with something else? if so what?

:OT:
i would also like some ideas on how to make the car louder should i make 'em straight pipes with a glass pack or what?

Thanks for the help

 

[htwheelz67]

if your just stroking it and leaving everything pretty much the same you will gain about 40 ft lbs and maybe 20hp, now if you add better heads, cam, intake,ex you can add 150hp to it.

 

[MitchGT]

Put a 351 in it. The 50 extra pounds won't hurt in a big car like that, it'll be cheaper, and you can put more abuse on it if you want (nitrous)

 

[mustangmike6996]

what mods do you need to convert from a 302 to a 351? i like the 331 and the 347 for the 302 with some good flowing heads and a sweet cam they make great power.

 

[coolblue65]

In regards to your first question about how much power you have now, if your 302 is bone stock the answer is: not much, low 200's maybe

A well built 347 will put you over the 400HP mark easily, spend a bit more and 450HP is no problem.

hell in a '71 I would be looking at putting in a Cleveland! But if not that definately a 351 Windsor.

 

[S-Car-Go]

You could stroke a 351.. 408 would fit real nice.. Not much more $ than a 347..

And it will be louder

 

[D.Hearne]

Why bother stroking a 302 in a 71 when bigger engines will fit ? Either of the 351W or 351C are direct swaps, and if you want more, the 460 fits comfortably.

 

[blown65]

I'd go a 351 based build with a 393 stroker. Least expensive stroker to do. With the money saved, buy some good heads like some AFR 205's and you should have plenty of HP.

As for the clev, I'd pass. Just my opinion. We yanked the 351C outta our Pantera and put a 408w in it with flat tops, smallish solid roller cam and AFR205's, has way more HP than that car needs.

 

[shatter]

Do you need to swap in different front springs to account for the extra weight of a 351 over the 302?

From what I've read, the 331 stroker is "longer lasting" than the 347 due to depth of the piston and relative location of the rings. No idea personally since I have a stock 302 in my 69.

 

[htwheelz67]

I should have recommended the 351w but you asked about stroking the 302, with a 351w you can use just about everything thats on the 302, you will need a new intake, headers may or may not fit but cast manis usually do, on my first 289 to 351w swap I even used the balancer, pulleys, flexplate, 289 converter, all the accesories and brackets, The only mods were grinding down and installing a heli coil on the 351w P/S bracket adapter that puts it in the same place as a 289, even my headman headers fit. I'm still using a lot of it on my 408 stroker.

As far as springs, no you dont need to change them, if you go an alum intake and headers the wieght will be less than the 302, if you go alum heads its even lighter. Some of the cast stroker cranks and rods are lighter than the stock 351w internals as well.

If you want to go the cheapest bang for the buck, drop in a 460 and trans, your car came with a 429 as an option and they are externally identical, mild cam, intake/carb/headers and it will feel like you have 2 302's under the hood, all you will need is motor mounts for a 429 and maybe a crossmember. oh yea a BB radiator. If I had the 71-73 I'd have a 540 stroker and a 5-6 speed or AOD.