I want to be able to jack the car easily at the track without driving on a ramp or wooden blocks.

So I was thinking about building 4 square steel or stainless "platforms" which will be placed under the car, over the flange underneath the door sill. This at the same place you position the small jack that is originaly provided with the car.

Those "platforms" should distribute the weight over the door sill, floor panel and the structure inside the door sill.

What do you guys think?

I have had loads of work restoring both door sill because they were rotten away. Will they hold up if I make such thing and jack the car?

 

First off, you should identify the model in question. In looking through your garage link on the site, I see you have a 1991 turbo. This response goes with that assumption.

I believe you are looking at some way to hold the car up at the track in order to do service. I am presuming you will lift the car up vice drive it on ramps, if I understand you correctly. Don't waste too much time building something special. You should be able find inexpensive jack stands to hold the cae up for this purpose. However, what you will need is a small hydraulic jack for lifting.

The sills are for the small tire change jack you mention. In doing any "real" work, you want stands. Search the following link. Has teh entire FSM.
1988 Mazda RX-7 Factory Service Manual

Look at the very first item / PDF doc. Look at paged G-6 and G-7.

There are two "rails" under the car. Almost like body-on-frame construction, but not. There are also lift / jack points for the front and read. Look carefully - front cross-member and differential. Use there to lift the fornt or rear. Then place jack stands at the appropriate points on the "rails".

If you choose to lift at the side sills, you run the risk of crushig the vertical tab. I had some shop that I thought was competnent, but found out the opposite. Some people thing every car is an old American body-on-frame car and can lift anywhere. As%#)*^@! Live and learn.

Hope this helps. Has worked well for me over the years, at home and at the track.


R/
John
88 GTU

 

It is indeed a 91 turbo, but what I had in mind goes for all second gen models.

I have a good and low aluminum jack, but the jack is to short to reach the frame rails (or how do you guys call them) because the rear half of the jack is higher then the front piece. click here to see the shape of my jack

So the jack DOES fit under my car, but I cannot reach the diff because I will hit the rear diffuser, and I can't reach far enough underneath the car because I will hit the sideskirts.


If you look at page G-7, you will see that the oem jack will be place under and around the door sill flange. And that is the exact spot I was thinking of making sort of a box that also fits around that flange so when I jack it, the weight doesn't crush that flange. Or vertical tab as you call it.

On the picture below you can see the door sill and that flange where all parts of the floor and door sill is sport welded together:





On the next few pictures you can see how it was, so I guess you can understand why I am very carefull on where to jack the car. The "bubble shaped" piece behind the front wheels was completely crushed when I bought the car because the jacked it at that point.

 

Do it, it's the stock jack point, I don't see why it wouldn't work.

I always wanted to reinforce the center of that pinch weld so I could lift the whole side at once to change wheels/tires on the entire car by jacking twice.

The rocker area is strong and it causes the pinch weld to bend before the floor caves in. The pinch weld is designed for jacking with the OE scissor jack. That's obsolete for you so modify it!

 

Back in the day I was helping build a track car and we welded some 1/8" angle iron along the pinch weld the whole way. Allowed jacking anywhere necessary and prevented crushing the weld. Also likely stiffened up the car a little.

 

cringing seeing that rust!

 

Yeah. Excellent job done restoring that area.

 

 

I have a real heavy piece of oak that I cut a groove in, similar to what is on the jack in the post above mine

for my other car I used a jacking puck, people tend to make these out of old hockey pucks, mine is aluminum and fits into the slots of the car's frame.
I bet a hockey puck with a groove ground into the middle would work for the FC

 

That is a really good and clever idea.

 

Here's the dream...

 

All be it at more then most of our cars cost. Oh well. It's a dream.

 

Weld some square 1x1 steel tubing behind the pinch rail at the points you want to jack from. Paint it and you are done. You can weld square tubing down the full length if the pinch rail if you desire.

The pucks are nice for the garage but fumbling with that stuff is a pain at the track where the ground can be uneven and you are in a hurry.

Here is a full length jacking rail.

 

^Nice!^

 

This is something I would make (semi) permanent to the car. But I had my doubts about.


Air jacks are awesome, but not for me. It will be when I would transport the car from and to the track so I can bring a bottle of compressed air.