240Z V8 Conversion – Small block Ford

240Z V8 Conversion – Small block Ford

This is a report on my installation of a small block Ford motor (in this case a 289) into a ’71 Datsun 240Z – I refer to it as a Z8. I’ve always loved the looks of the early Z-cars, and the sound and power of Ford 289/302s, and happened to have an engine “in stock,” so decided that I would do the project. I had to acquire the Z for this, and my goal was to make a high performance street car with subtle cosmetic enhancements, but still appear fairly stock to the innocent bystander. I wanted everything on the car to work as original after the transplant. Since this is an "all for fun" sort of project for me, I decided that I would try to do everything right, and not be so concerned about the cost of things, and how long it takes to do it. Even with buying the car, restoring it, the chassis changes, an interior redo, and a paint job, I figured that it would be way cheaper than anything else of comparable performance and looks. And what’s a hobby for if it isn’t a way to use up time and extra funds?

Here's what completed Z8 looks like on the outside.

And this is what it looks like in the engine compartment. Motor looks like it was designed for the car.

There are kits available to put small block Chevy motors in Z-cars, and consequently this seems to be the most popular route. However, the Chevy motors are heavier and larger than the Ford motors, and with the rear-mounted distributor must be mounted further forward and higher. What could be better than a motor that is lighter than the stock Z motor, can be mounted further back for better weight distribution, has better exhaust sound and torque than the stock motor, and over twice the horsepower? Unfortunately, there doesn’t seem to be much documented about Ford conversions, so I was charting some territory without much helpful folklore on the web.

I’m writing this so that it might be of some help to others interested in this conversion. It might dissuade you from doing the job or encourage you to do the job after you read it. If you do go ahead with a similar conversion, it will hopefully save you time and the purchase of parts that don’t work since you can take advantage of my research and mistakes.

This could have been written to make the job sound easy, but I’ll go into details about how I did things and mistakes I made. If you read it and think, lordy, too much work for me, I can assure you it isn’t as hard as you would think. Just a simple matter of going out in the shop regularly to finish that last task or start a new one with the challenge of figuring out how to address the next step. My wife seldom saw me at all for weeks because each morning I was so excited to go out into the shop and enjoy the project. Even though I’ve worked on cars for years, this is the first time I’ve done an engine swap.

I am lucky enough to have a well-equipped shop with lots of room and lighting, a lift, milling machine, lathe and welding equipment. While you can do the job without this equipment, it would take longer and require some professional assistance to have some of the parts made. I’m also lucky enough to be retired so I have a lot of time. And the project needed it. Once I found a Z, I worked almost full time in the shop for a little over two months to do the conversion, although that time also includes doing a restoration of all of the running gear too. It could be done in less time if you aren’t so picky about the details and/or choose to not make all of the modifications that I did. It could also be done a lot cheaper in these same cases.

This is good old fashioned American hot-rodding at its best. Just make the car the way you want it. If you think it will work and look good in your eyes, just do it! There are many “right” ways to do it, mine is just one way.

Excuse me for the odd order of this. You will see pictures and tasks that are out of sequence. That’s because I tried to be generally sequential in the way I did the description, but in some cases grouped things about one subject together. Not entirely though – you will still need to read everything if you want the full scoop.

How does it drive? Well, in a word, fast. In two words, plenty fast. I’m very satisfied with its performance. It isn’t overly loud inside, but has a nice exhaust tone outside. It handles just as well as a stock 240Z, which is flat cornering, comfortable ride, and pleasant drivability. It feels tight and nice. It effortlessly hums along at about 2,250 RPM at 70 MPH. Care is required in first or second gear: if you punch it, both rear tires break loose. Fun.

Please feel free to email me, BrianLaine@aol.com, if you have questions or comments. I’d also like to hear from anybody who has done this conversion with smaller engine and transmission mounts. Mine are overbuilt, and I’d be curious to hear how much less would be workable.

I’ve also included CAD drawing for some of the parts (such as the motor and tranny mounts) to give you a head start if you decide that you want to do things similar to the way I did them. Hope they help you.

So let’s get on with it…

The car we're working with...

The motor we're working with...

Preparing the motor for a trial fit...

The transmission...

Mounting the motor and transmission...

The fuel system...

The differential and driveshaft...

The exhaust system...

The cooling system...

Pulling the motor and attending to the rest of the chassis...

Installing the motor for hopefully the last time, and clutch headaches...