Lighter = Faster (RX-7 Build #2)
- Thread starter magnumP5
- Start date
mymmeryloss
Member
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- 13bT Mazda B2600i
Well either way, im glad i found the new build thread haha
With the amount of time + money I've put into this car I'd need to start looking for parts to make it a 2+2. I only have one seat as it stands right now anyway...
It's out of the garage and at the body shop now. I should get a call later this week or early next week after sand blasting to go over the damage. Anxiously waiting...
With the car out of the garage I dedicated the weekend to finishing the front ducting and cleaning up. I'm pretty happy with how the duct turned out. I'll have to take some pictures tonight since my phone died yesterday. It's a multi-piece design that fully seals from the front of the car to the oil cooler and radiator while still allowing the stock mounting of both. Two removable side plates allow the duct to encompass the oil cooler but remain as a separate piece. I also split the duct for dedicated flow to the radiator and oil cooler each, roughly following the 1/3 area rule.
mymmeryloss
Member
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- 13bT Mazda B2600i
Cant wait to see pics
Ask and you shall receive:
Oil cooler installed:
It's not perfect. I really wish I had a bead roller to increase the rigidity of some of the panels. Aside from confirming the fit when I get the car back the only thing I want to do is add some weatherstripping around the mating edges to reduce wear and perhaps give a better seal.
mymmeryloss
Member
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- 13bT Mazda B2600i
That looks killer!
Thanks! It would've turned out better with a waterjet, sheet metal brake, a bead roller, and some TIG welding but an angle grinder with a cut-off wheel, two pieces of wood with vice grips, and pop rivets had to do.
I've had some fellow rotary enthusiasts actually warn me water and oil temperatures might get TOO COLD with this setup. I still have the both thermostats installed so we'll see. If that does happen I can always make some inlet restrictor plates.
mymmeryloss
Member
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- 13bT Mazda B2600i
Too cold? Thats crazy. Ive never heard of anything ever being cold on a rotary.
I guess anything is possible. It seems like the main concern would be fatiguing the thermostat in the oil cooler due to more frequent cycling.
Soo... I got a call from the body shop yesterday. The car's back from being stripped. They ended up sending it out to be chemically-stripped instead of sand blasted. The whole thing looks like it's been etched now. I didn't get any pictures because I was in a hurry and needed to do some other things while I was there. Fortunately, there were no surprises. The only holes were the ones I was aware of. Next steps are reapplying seam-sealer and welding up the holes I don't need (about 50 of them). I have to go back on Friday to drop off the roll bar (they're making stronger mounting points) so I'll try to take some pictures then. Went ahead and ordered some new front body work (right bumper/core support) as well.
mymmeryloss
Member
- :
- 13bT Mazda B2600i
In for pics [emoji41]
Snapped a couple pics when I stopped by the shop yesterday to drop off the roll bar.
The pieces of tape everywhere are holes that are going to be filled in.
The shop has some interesting ideas about the roll bar. I need to look into the NASA and SCCA rulebooks to see if it's legal, but maybe someone here knows. I want to keep the bar bolt-in but I wanted more strength at the attachment points so I asked the shop to weld some 3/16" or 1/4" plates to the car. They came up with a neat idea to build little boxes at the attachment points with welded nuts inside. This way the attachment points should be much stronger and I won't have bolts going through the body of the car. Legal?
The pieces of tape everywhere are holes that are going to be filled in.
The shop has some interesting ideas about the roll bar. I need to look into the NASA and SCCA rulebooks to see if it's legal, but maybe someone here knows. I want to keep the bar bolt-in but I wanted more strength at the attachment points so I asked the shop to weld some 3/16" or 1/4" plates to the car. They came up with a neat idea to build little boxes at the attachment points with welded nuts inside. This way the attachment points should be much stronger and I won't have bolts going through the body of the car. Legal?
mymmeryloss
Member
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- 13bT Mazda B2600i
I have no idea on legality but it wouldn't surprise me if its not legal. Those roll bar requirements are so weird.
Spent the weekend getting rid of crap in the garage - made $50 in scrap. After that it was too cold to spend more than 15 min. in the garage at one time. Organized wire harness crap and started working on the plate for mounting the RacePak.
Not bad for using only a Dremel, a file, and some sandpaper:
Backside with Racepak mounted and all my construction lines:
Front and in the bezel:
Still need to drill holes for the indicators, attach the plate to the bezel, and paint.
Not bad for using only a Dremel, a file, and some sandpaper:
Backside with Racepak mounted and all my construction lines:
Front and in the bezel:
Still need to drill holes for the indicators, attach the plate to the bezel, and paint.
Last edited:
Here are the words from NASA's CCR:
"15.6.14.A Mounting Plates – Bolt-In Cage
The attaching points of a bolt-in cage to the body must use reinforcing plates to sandwich the body. At least
three (3) bolts are required for each bolt-in plate and the plate must be at least 3/16 inch thick. All hardware
must be SAE Grade five (5) or better with 5/16” diameter minimum. All nuts must be held securely by a locking
system such as safety wire, lock washer, Nylock, or jam-nuts. Nylock or nuts that use metal crimping to prevent
loosening shall not be reused."
...and from SCCA's GCR
"9. E. b. The thickness of mounting plates bolted or riveted to the
structure of the car must not be less than the thickness of
the roll hoop or brace that they attach to the chassis, and
must be backed up with a plate of equal size and thickness
on the opposite side of the chassis panel. The maximum
area of each mounting plate must be 144 square inches.
Plates may be on multiple planes but shall not be greater
than 15 inches on any side."
and
"18.4.4. Mounting Plates:
The thickness of mounting plates bolted to the structure of the car shall
not be less than the thickness of the roll hoop or brace that they attach
and shall be backed-up with a plate of equal dimensions on the opposite
side of the panel, with the plates through-bolted together. A minimum of
three (3) bolts per mounting plate is required for bolted mounting plates.
All hardware (bolts) shall be Grade 5/Metric 8.8 or better with 5/16”
diameter minimum. Mounting plates welded to the structure of the car
shall not be less than .080” thick. Whenever possible the mounting plates
should extend onto a vertical section of the structure (such as door pillar)."
Seems like the idea is a no-go even though our idea is basically a weld-in/bolt-in bar. Those requirements are for competition and though I don't plan on competing in this car beyond time trials I don't want to push it.
So just about ever club code, regulation, etc. mentions a backing plate for bolt-in roll bars so it seems our plans need to be changed. Kind of annoying because the engineer in me says my idea, basically a plinth box for a bolt-in cage, would be stronger than simply sandwiching the body between two plates. Unfortunately rules are rules and you can't argue with 'em. Even though I won't be (seriously) competing in this car I want to make sure everything conforms to competition rules (except the part about having a full cage). I'd rather not have to play 20 questions every time I take the car to a track.
Worked on some more block-off plates last night since it's been so cold. Played with .025 in. Al and the leftover .063 in. ABS I had leftover from my door project.
Al plate for the radio delete:
ABS delete for the center console:
I made two of everything, even the Racepak plate. One out of Al and one out of ABS. I'm not sure which I want to use. The ABS is lighter and looks better, but I think that's just because it's black already. I'm leaning toward the Al because it's stiffer. I plan to mount USB ports for the display and Haltech in one of these panels so the extra stiffness is better.
Worked on some more block-off plates last night since it's been so cold. Played with .025 in. Al and the leftover .063 in. ABS I had leftover from my door project.
Al plate for the radio delete:
ABS delete for the center console:
I made two of everything, even the Racepak plate. One out of Al and one out of ABS. I'm not sure which I want to use. The ABS is lighter and looks better, but I think that's just because it's black already. I'm leaning toward the Al because it's stiffer. I plan to mount USB ports for the display and Haltech in one of these panels so the extra stiffness is better.
This. With all the body work you're doing to this chassis why not just weld it in?
Seems kind of silly to weld in a roll bar, no? I don't think a full cage is ever really going to be needed for what I plan to do. I still want to be able to install the interior trim/carpet. However, it might be possible to position everything in a manner to allow this. It'd look weird having a white/gray/orange/yellow/whatever roll bar in an otherwise black interior. I'll see what the body shop thinks.
