Ever since I first saw this photo 2 years ago, I've always wanted to do something like this with my car. I got my S5 as a salvage because the front right side was hit. It didn't do any damage to the actual frame, but all the thin metal brackets that the bumper, lights, and fender bolt to were twisted and such. Its really not that bad at all. You can hardly tell from the outside so I'm not 100% sure why it was titled salvage.




Now, I've always wanted to upgrade to a v-mount, have twin oil coolers, and have proper duct work, and after seeing this photo, it would fix my crooked front end and give me everything I wanted performance wise. This kind of setup would help with a full undercarriage belly design too.

So what kind of tubing do you guys think would work good? I was thinking of using 6061 (aluminum) 1.5" OD with a wall thickness of 1/8". The other option would be to go with something along the lines of 4130 (steel) 1" OD with a wall thickness of an 1/8 as well. Id preferably like to use aluminum but Im worried about its strength in an event of even a small fender bender. I haven't really seen any 6061 3/16" wall (which I would rather use than 1/8") so next up would be 1/4". That seems kind of over kill to me but maybe that would be the better route to go for strength. Need some input for the sizes there.

The other part that worries me about this design is the reinforcement bar that connects to the strut tower area. Suppose, once again, in the event of even a small fender bender, all the energy would be transfered back to the strut towers and collapse them in. That would be serious work to ever fix for then alignment would be an issue. Or do you think the way things are angled, that the aluminum would bend and absorb the energy before it bent up the strut tower?

Thanks -Mich

 

That's a full race car that will never see the street. For street car you really should have proper bumper supports.

 

yeaaa one hit to the front of that and youre gone for good

 

as soon as i moused over the thread title and saw your first sentence i knew which pic it was going to be

 

If I go this route, I do plan on making a similar setup to the stock rebar. It would definitely be more reinforced on the frontal part than the picture. And do remember, most people take out their rebar to put a decent size front mount on anyways. So this would at least be better than that.

 

I'm not sure if you want to spend the money for an experienced fabricator to make a street-safe frame, and it is certainly a bad idea to attempt to do so yourself. What I can tell you about that picture is that the intercooler is too thick for a street car, and the end tanks are not routed as efficiently as they could be.

 

Look at everything else that he has cut out to make that fit. While I commend him on his effort, I think for a street car that is about the worst thing you could do. Look closely at that pic and then visualize what would happen with small amounts of force applied to certain area's. It looks like parts of it would cruble like a tin can. Not to mention there is no direct support for the frame rails either. A decent shot would crumple even the frame rails. Mazda designed the front of thier cars the way they did for a reason. I doubt you're smarter than them.

There's alot that can be improved upon there. Great idea, great execution of a poor idea. I built a tube frame for my VMIC and it looks NOTHING like that and things are better routed than that.

 

future modification on may spare car, whats the difference between a crash on the streets or on the track?

 

Could you by any chance post those pictures in here Titanium? I'd like to see how you did your setup.

 

Here is the stock setup for reference. Sorry it's kind of small.

 

Gee I dunno, could it be the cage or car, the helmut, the racing seat, the 5 or 6 point harness

 

Look at everything that he cut away and then tell me you have the ability to stregthen a car the way the factory did and safely put it on the street. I know I don't

This is all you get for now

 

Now I've seen those pictures before, but lets see the assembly process!

 

stock twins??

 

Yeah, that is how it looks to me too. Then again, I am not a structural engineer, so I could be missing something.

All of the truss framing on my car was designed by a NASCAR safety inspector who owned a shop that specialized in movie stunt cars. My other RX-7 had the roll cage installed by one of the leading SCCA rotary race shops with decades of racing experience. IMO this is not one of those things you want to screw around with if you are a novice safety engineer.

The intercooler plumbing, on the other hand, is a little closer to my area of expertise.

FYI for those looking at the two setups, notice how the intercooler pipes shoot straight out of the end tanks on TitaniumTT's car. The minimal bends reduce the pressure drop within the tubing, probably by about 0.2psi or so. Were there more bends and/or tighter bends, the turbo would need to spool faster to produce the same manifold pressure boost level, which means more lag and more heat. The car in the picture posted by limbar85 does not do this quite as well, but it is still pretty good. However, why not make it as efficient as possible?

 

Well, one reason to design your end tanks like in the first picture posted would be to more evenly distribute flow over the all the tubes in the intercooler core by placement of the inlet/outlet and by introducing turbulence into the end tanks. This increases the core efficiency.

This does increase pressure drop thereby decreasing compressor efficiency as noted, but IC design is always a balance.

TitaniumTT could have put dividers/turbulators in his end tanks as well to help with the inferior flow distribution of the inlet/outlet locations, we can't tell by looking at the outside.

I know that for my IC which was a well designed Isuzu NPR core I relocated my inlet/outlet to the same position as TitaniumTT's and cut out the turbulators in the end tanks as to reduce pressure drop at the expense of core efficiency.

I wanted good spool so I focused on reducing intake pressure drop everywhere and maximizing pressure drop on the exhaust side of the turbo.

 

Nope, not yet

FD twins and they are not stock.

All of the truss framing on my car was designed by a NASCAR safety inspector who owned a shop that specialized in movie stunt cars. My other RX-7 had the roll cage installed by one of the leading SCCA rotary race shops with decades of racing experience. IMO this is not one of those things you want to screw around with if you are a novice safety engineer.[/quote]

I've had a structural engineer tell me that figuring out how **** will crumble is easy, how to make it not crumble and do the corresponding math, that's the hard part

I did alot of research and read a bunch of threads that you posted in and used a bunch of common sense when I was planning this out.

I spoke with both PWR and Sparco about the endtank design. I had originally wanted to do piping that entered and a less severe angle and or strait into the core. I was told that becuase the length would be so drastically increased, the additional length would negate any pressure drop by more effiecient tanks. Air will flow towards the path of least resistance. When certain passages have less pressure than others, they will be filled until equal.