1967 Mustang 289 Stroker ?

by Rick Franke
(Alberta, Ccanada)

Question:

I have a 67 Mustang with a regular block.

Can I stroke it? If so, is it worth it?

I'm thinking of adding a cam and boring it over along with the stroke. If its worth, it is there a good stroker kit or combination that you can share with me.

Is it maybe easier and cheaper to go with a 351 ? Iit's got what I'm guessing is a c4 tranny. Is this ok if I go to a 351 V8 ?

I also believe that the Mustang rear differential is from a Mustang. If it is, what rear differential did the 67 mustang come out with ?

Answer:

You have a lot of good questions that people keep wanting to know.

First off, yes, it's possible and you'll get a good solid performance increase, by stroking your 289 V8.

Whether you go this route, or swap in a 351 the first question you may want to ask, is whether you want to keep your classic Ford Mustang as original as possible, or does it matter?

If you already have a good solid stock block to work with, you can find stroker kits from less than a $1,000 to twice that. What you spend, is directly related to what you want those extra cubic inches for.

Are you looking for a nice bump up in horsepower on a street car that may take a trip or two at the track, or are you looking for something that is mostly, or only a race car?

Probably the most common stroker kit is a 331 stroker. I'ts based on increasing the stroke of a 289 that's been bored .030 over.

It'll give you a good horsepower increase in your 1967 Mustang. And if you decide later that you could use even more power, adding some aluminum heads with a stroker kit will likely up the power by another 100 hp.

A bigger stroker kit is the 347 stroker. This yields bigger performance gains, but because the rods are longer they must be set very high up into the piston crown.

There are better kits now than in the past, but the main issue, is that the pin ends up in or very close to the bottom ring land (groove).

Many 347 stroker engines have oil consumption problems, which also can be an issue if you have to pass emissions tests.

351 V8 stroker

There are stroker kits available for the 351 and of course, you can just do a performance build up on a 351 Windsor or Cleveland engine.

Ultimately, there is potentially more power to be had from a 351, since the overall displacement will be bigger, both before and after stroking it.

A C4 automatic transmission is a good strong transmission and can take a lot of power. But as you probably know, the C6 is what specs out for the big block V8 and is designed to handle higher output.

Rear Differential - Gear Ratio

If your 67 Mustang still has the original rear end and it has the metal tag still attached, you can decode it to find the axle ratio.

Or if you still have the door data plate, the axle ratio code will be listed on it.

There were quite a few axle combinations available for the 67 pony car. It not only depended on which engine you have, but factory optional ratios were also available.

If you have neither, you're stuck with jacking up the car and putting the rear end on jack stands.

Measure how many turns of the input yoke (where the driveshaft attaches to the axle) it takes to make one full revolution of the tire.

That's your rear end axle ratio.