Project "independence day"IRS and 3500 swap

[caffeine]

Is that loop track legal? Last time I read the rules I seem to recall that the loop is supposed to be within 1 inch or so of the driveshaft all around. I could be wrong though.

[Driver_10]

Damn, I just looked up that rogue fab bender... Those aren't that expensive if your buying it for one tubing application only... I'm quite surprised. I'll have to mention that to the race car driver I work with next time he wishes we had a bender.

It was like $690 or something "shipped". (With Some small amount of welding required)

Its a great bender that makes good, tight radius bends fast and easy! Plus its American made. No Chinese slave-labor bullshit!

[3400-95-Modified]

Damn, I just looked up that rogue fab bender... Those aren't that expensive if your buying it for one tubing application only... I'm quite surprised. I'll have to mention that to the race car driver I work with next time he wishes we had a bender.

[Driver_10]

The hoop weldment only weighed around 12-13lbs. The structure tubing is a lot lighter than it looks.

[1988GTU]

I'd be happy with 40*F LOL!


Nice progress. Are you concerned with how much lbs that loop will add at all?

[Driver_10]

I went ahead and cut my pipe forms to make it fit into the rail. It was made to accomodate both being a drive-shaft safety loop and room for the exhaust pipe on the right hand side. (Notice the off-center mounting)










After a little test fit, I realized that the hoop was entirely too low. Not a problem. I just modified it for proper height and re-checked it!










After I rechecked the final install height, I cut the cross-beam and tacked it into place! (I also moved the battery tray over to the other side. It now sits behind the driver's seat)


Im going to stick my 220v space heater under the tarp and see if I can get my work area heated to around 75 degrees or better. If I manage that, Ill have some more stuff to post up for an update!

[Driver_10]

Ive been working on the car since the I got home 2 weeks ago, and made some good headway up until 2 days ago when the rain and freezing temperatures came into town.

To start with, I went ahead and bought supplies to build an all stainless exhaust.


This catalytic converter cost me 450 bucks, which seem excessive, but there were no cheap 3-way cats capable of flowing the air needed for this engine to run, let alone pass an IM240. Remember... this IS a street car. (Ill have a test-pipe ready for track-day)


Ill be using the same style stainless mesh packed muffler as before. Straight flow-through design and quiet operation.


I went ahead and got my bump-stops fabbed and welded into place. You can see the dry-sump oil tank sitting above it. (I moved the tank to the rear of the car now.)


I also made a few changes to the frame since the weight of the frame was starting to exceed the 145lb limit that I had placed on it. (the gas tank holds 120lbs of fuel, so weight is crucial) I went ahead and cut out some of the reinforcement so I could replace with lighter/ sleeker equivalents.

*Tee hee* quite a bit of slicing and dicing. I even sliced up some portions of the fuel cell cage.


I even made room for the exhaust to run out of the rear of the car now. The exhaust will be routed over the differential, and around the tank (None of which is can be seen in these pics, but the space is there!) The exhaust will never drag the ground.


I also went ahead and started putting in the wheel wells. and started prepping the car for sheet metal!
First cardboard templates...




Then on to the sheet metal! You can see the magic marker outlines for the tubs. All panels be done in 12g aluminum.








I also started fabricating the combo drive-shaft/ exhaust loop. That rogue fab tubing bender is one of my better investments. 180 degree bend with no crimps!

[3400-95-Modified]

Just as you've stated, the cell has a plastic bladder in it that is made of polystyrene. In the case of an impact, the bladder will crush, but not puncture. It is protected by a metal case that surrounds it and has built in roll-over protection.

I will be installing one more bar across the bottom, between the diff and the cell later.

(BTW... good job on the explanation)

This is true, but I just think having that one extra bar in the front preventing any forward motion would be a good insurance policy... but it sounds like you have something planned for that. My thought is probably over building the car anyways

[Purple pit]

LOL still looks a bit low without the engine. Oh man there is a baby....don't know what it is about them, but I love the NSX. Must be the looks, sure is not the HP, but who really needs 800hp anyway.
I'll sure be watching on the diffuser. Can't wait to see how it's set up.

[Driver_10]

Nice work as always. To me the tank is sitting a bit low. Pot holes, dips in the road and speed bumps bring a fear of the tank smashing into the ground. A skid plate could help, but I don't like sparks near fuel. If there was room I'd go with a shorter fatter tank. If it hits the body is going to have to eat alot of force. Hard enough and the back glass could blow.

The cage appears lower than what it is at ride height. The rear wheels are sitting kow and the car doesn't have an engine in it right now. The front end is practically looking up at the clouds.

The tank sits level to the rear differential. I did this to give me a good place to mount the rear diffuser later. Something like this...

[Driver_10]

Only question I have is you removed the front center support to clear the rear so now there is nothing technically holding the cell back other than the top mounting bolts (that are only going through two layers of sheet metal...) I look at that and say the cell could slide forward in an impact and quite possibly puncture if it hits the IRS setup just right. It may be ok as is but it's just something to think about depending on if your trying to meet specific rules at any track or something.

Just as you've stated, the cell has a plastic bladder in it that is made of polystyrene. In the case of an impact, the bladder will crush, but not puncture. It is protected by a metal case that surrounds it and has built in roll-over protection.

I will be installing one more bar across the bottom, between the diff and the cell later.

(BTW... good job on the explanation)

[Purple pit]

Sounds good to me. I love how self sealing has become self healing, but I'm old school.

[3400-95-Modified]

Wow didn't know that about the race cars. Man, for a street car that still puts a ton of fear in me. Is the bladder self sealing?

Yeah that's kind of the whole point... The bladder is just in the square cell and it's bolted to the top fill port with all the nuts you see... that's the only opening of the bladder so in theory with a Kevlar bladder you should be able to crush that box or have welds split on it from being bent, BUT the fuel should not leak...

Info on a very similar brand to JAZZ

http://www.atlinc.com/atl-fuel-cells-photo-gallery.html

[Purple pit]

Wow didn't know that about the race cars. Man, for a street car that still puts a ton of fear in me. Is the bladder self sealing?

[3400-95-Modified]

Nice work as always. To me the tank is sitting a bit low. Pot holes, dips in the road and speed bumps bring a fear of the tank smashing into the ground. A skid plate could help, but I don't like sparks near fuel. If there was room I'd go with a shorter fatter tank. If it hits the body is going to have to eat alot of force. Hard enough and the back glass could blow.

You would hate to watch a race where I go then... All the modified series cars have a very similar fuel mounting position and height is even lower... 90% of the time when you see sparks leaving from under the vehicle its from the fuel cell cage or frame rail bottoming out right there. That's why that cage is around it. And its a cell so there is at least a hard plastic or kevlar bladder in it.

Only question I have is you removed the front center support to clear the rear so now there is nothing technically holding the cell back other than the top mounting bolts (that are only going through two layers of sheet metal...) I look at that and say the cell could slide forward in an impact and quite possibly puncture if it hits the IRS setup just right. It may be ok as is but it's just something to think about depending on if your trying to meet specific rules at any track or something.