Hey guys here is the new custom design I am going to be getting done for my car. The SFCs will be made of square tubing instead of round tubing and they will be made from chome moly. The stage 1 tubing that runs the length of the frame rails and welds to them at 3 locations will be 1 in and the cross bracing will be 3/4 in square tubing. Instead of being bolted together the center section will be welded together and bolted into their box holders.. I will explain those later. So the center section should still be removable yet this design should provide a better more stable fit.

I am going to be adding 2 additional lateral supports as you can see in this picture.


I said to the guy try and make them as close to the ends so that they connect at the tabs if you have the clearence to do so but if you dont move them in closer and closer to the center untill they clear.
More like this


This should add some more lateral support but the biggest problem with the old design was the way the bolts connected to the tabs thus instead of tabs boxes are going to be used. If you remember I am using square tubing with capped ends much like this


Those square tubes are going to fit into 3 sided boxes with one side open on the bottom so you can slide the square tubing into the boxes. These boxes will be located where the tabs used to be. The clearence will be tight. When you slide the stage 2 cross bracing into these boxes the capped end of the tubing should be right against the back of the box. I drew I diagram of the box below. The open end of the box would be where the square tubing would be sticking out. Then to keep the tubing secure there will be bolts going through the box and the square tubing in 2 spots. So there will be 2 bolts for every box to spread stresses over a larger area.



Hopefully these pictures have given you guys a better idea of what I'm getting done although if not I dont blame you, the last time I had art was in 6th grade and my teacher (No lie) said I was artistically retarded.

I have the car now, he did measurements on Fri and I am bringin it back Mon morning to start fabrication. I'll keep you guys updated.

I really hope these things come out great (keeping fingers crossed)

P.S. I am going to be posting this in multiple forums as it concerns more than just 5th gens. So mods please be understanding about that.

 

how much do SFCs cost? i have really been wanting to do this lately but the price combined with the fact that i cant install them myself has kept me away. do they fit with aftermarket cat backs and y-pipe/headers?

 

None of that can be determined yet. When I brought the car in for measurements I gave the fabricator pictures of 5th gens with headers and aftermarket exhaust so he has an idea of how much clearence to leave but he can make no garuntees because my car doesnt have headers or aftermarket exhaust, but if my car comes out well I am guessing others will bring their car to him to get the same thing done. I am sure some of which will have aftermarket exhaust.

As for right now I am paying 400$ for this setup fabricated and installed, but you have to remember the price was 300$ before I added the 2 additional lateral supports and the box idea. I wont make official statements but I would think if you just wanted a stage 1 (just the bars that run the length of the sub frame rails) you could choose a larger diameter tubing and it prob wouldent cost more than 250$. And you could put tubing in there as big as would fit. That way you wouldent have to worry about aftermarket exhaust systems fitting.

we also asked what this would cost completly made from aluminum, which is also an option but that would probably be about 600$ or more. So I am guessing most people wouldent do that.

 

Why are you using square tubing?

 

The guy fabricating them wanted to use square tubing, plus the whole box idea wouldent be possible without square tubing. I have to say the best combination strength wise would be to have the stage 1 bars be round tubing and the cross bracing stage 2 bars be square tubing but it would look silly and this isnt a race car, thus I dont need maximum stiffnes, the fact that they are using chromoly alone should make this much stiffer than the old warpspeed kits.

 

UPDATE on the SFCs. I did some research on the strength of round tubing VS square tubing and found that round tubing can be somewhat stronger while being lighter. So for the stage 1 bars that run the length of the cars I've decided I am going with round chromoly tubing, because of some of the things I read in this article from factory five racing.

http://www.factoryfive.com/table/ffr...ecs/frame.html

Mainly because round tubing had more tortional strength which the chassis and thus the stage 1 bars will experience some of. The square tubing is better for vertical strength. Thus they would be better for the center stage 2 section. And the box connection is very good. So there will be a combination of square and round tubing and the combination should be the best for weight saving strength and good connections on the bolts.