good luck at the runoffs!

Thanks!

Spent ALL DAY yesterday on the dyno, making decent numbers. A little more prep tonight, then in the trailer for a Friday morning roll-out to Indy.

So tired.

Does anyone have the weight for a car with tube front, rear, subframes, polycarbonate windows, fully gutted and caged, and all carbon/fiberglass body panels and doors? I'm wanting to go balls to the wall on my time attack build after I finish my autox car and I'm just curious how low you can actually go.

Sounds costly; what classes do you intend to compete in?

Would suck to spend a ton of money and not be able to be competitive in your resulting classes.

I'd be in XP class with the motor swap alone so I figured I may as well go all out with other mods. I'll need to be as light as possible to be competitive at all. I do believe that there are restrictions on under trays and some aero stuff, suspension etc. But I'll be building most of the stuff in house at first to cut down on costs.

I'm down to 2920 with 1/4 tank and me (190lbs) in the car. so low 2700s. Car is full interior street car, quiet, comfortable, A/C, radio, carpeting, cruise control, only the driver seat has been changed to a fiberglass race seat. My youtube videos have more details. Not bad.

Which region do you plan to hillclimb with? i'm planning on getting into SCCA hillclimbs this season with PHA.

The lightest my car has weighed at impound is 2860 with me in it, so approximately 2660 without me. It's about to get a little heavier, probably, with the addition of a wing and front aero. I'm not sure where I'll take more weight out. I'll have to start getting more creative, like rewiring and such.

I'm at 2570 with about 4 gallons in the tank. No cage, full interior minus rear seats. Swapping out the renesis, PPF, rear end and stock trans saved a lot of weight.

Still need to add the splitter and wing.

which drive train are you running? the stock diff is so overbuilt and heavy, compare to an Evo8/9 diff i had sitting around.

Turbo 2.5L MZR

https://www.rx8club.com/rx-8-racing-...rx-8-a-267751/

And an FD 5-speed trans, and an aluminum Ford 8.8 IRS rear. Both are a decent amount lighter than the stock RX-8 stuff. Removing the PPF saves a lot of weight as well even after adding an overbuilt trans crossmember.

are there any bolt on solution to deleting the PPF while keeping the stock diff and tranny.

The LS1RX8.com kit includes PPF delete hardware. You can use it with the Mazda factory diff but you'll have to modify the trans mount portion to deal with the fact that it's designed for GM transmissions.

You can get the diff mounting hardware here:
https://www.ls1rx8.com/store/p7/Rx8_...nting_Kit.html

Their trans mount is here:
https://www.ls1rx8.com/store/p91/Tra...ossmember.html

that diff mount kit looks way simple to make for it to cost $600

also found this one with google search.
with the nzd to usd conversion, it's around $750 for the entire kit.

http://racefab.co.nz/RX8.html


https://cimg8.ibsrv.net/gimg/www.rx8...929c87bb24.jpg

https://cimg3.ibsrv.net/gimg/www.rx8...783761ad4f.jpg

https://cimg5.ibsrv.net/gimg/www.rx8...2220553881.jpg

https://cimg2.ibsrv.net/gimg/www.rx8...f3c140f5de.jpg

how much does the ppf weigh? (I have not removed mine yet) those replacement parts don't look very lightweight either..

My time trial car is 2350lb with a couple gallons fuel, 6pt cage, dual element rear wing, front wing, flat floor, diffuser etc, 315/18s, Stock glass, s2 trans, still have the ppf. I suspect high 2200s would be doable without the aero and certainly without the cage

Don't plan on it weighing any less as next season will be adding power

Any pics of the interior? Any fiberglass/carbon body panels? Seems unbelievably low...
​​​

Heres a quick video I threw together to show someone the car a few weeks ago.

i see you got a bit a weight left on the doors. that's at least 40 lbs if you gut the rear and front door. but i guess you'd need a proper roll cage with door bars to go that far.

what's your max lateral Gs with all that aero.

Yes, if I had a cage in the car with door bars I probably would have went ahead and did that. To be honest the cage in this car is pretty much the bare minimum acceptable for the rules that it has to abide by. In a previous season / class I ran the rules were if you had a 6 point you could remove the interior, but you had to retain the factory dash, so I went with the lightest 6 point that cleared the factory dash and removed the interior which was a net savings in weight overall. If I end up adding door bars I will more than likely gut the doors.

RX-8 Mad Max style! :greenchai

I like it.