On the various tube frame cars that have their pictures posted here it looks like the 914s have been solid tubs from front firewall to back firewall but the the nose and rear end have been re-done with tubing.

Has anyone replaced the longitudinals with tube framing?

Why or why/not?

Just thinking about options for some of these cars which currently can't be saved.

seen it done but RULES typically prohibit. Original suspension pickups, longs and floor pan, or some thing close. We have, locally, a twin turbo 914 thats GTP or GTO grandfathered in, only looks like a 914 nothing left,.

depends upon class, but d914 is correct....

most classes will not allow it.

and for the ones that would allow it, it isn't really competetive anyways....

If your going to run in a full tube frame american type class, then your not going to want to do it with a teener.
b

The #22 Wayne Baker IMSA 914 car has the bottom of the longitudinals opened up somewhat at air is sucked out the top for engine supply so there is some downforce generated. Since that seriously weakened this area there are some tubes that are right next the longitudinals to provide support. As noted you generally have to keep the tub.

From the mouth of the orginal builder of that car.

"When I built that car I put the chassis up on my jig and started removing material. I took the rocker box/frame rail and removed it. Replaced it with 1.5 x 3 box tubing. This tied the whole car together. Then I started building the chassis up from there. Then I sectioned the car so much that Wayne was sitting with his butt on the floor and his head on the roof."

The engine was cooled with three fans from the 911s. These were the fans that were used to cool the thermal reactors on those cars.


The reason most 914s are not done this way is because it is too much work. In my opinion most 914s that are running in a class where a tube frame would be necessary their competitors cars are below the level of prep that would require such a chassis. I know PCA rules require that the firewall be kept intact. I think SCCA changed this, but most require some kind of firewall that resembles the factory stuff.

Another thing, most people don't care to look this deep but, the factory box section is stiffer than what ever tube you could put in its place. it is very light as well. I know this will bring some flames but if you run the numbers you can't deny the facts. With some strategic placement of tubing and sheet metal you can make a very rigid chassis. I will be doing some chassis torsional testing this winter. I am going to test the base stock chassis. Then, I am going to build the bare minimum cage and then measure the torsional stiffness, then change what is still flexing. I will keep people posted.

I don't remember where these came from or any specifics except for the obvious, that it
fuqqin' kicks ass!

#2.