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Modified Mag RX-8 project car -- STX here I come!

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Old May 17, 2011 | 03:39 PM
  #276  
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Originally Posted by ganseg
Somehow I missed the May issue - someone mind giving me a recap?
http://www.modified.com/projectcars/...hop/index.html

The July issue has an intro to the engine build. Housings are at Goopy now, lots of other cool stuff in the works for this engine (maybe even peripheral ports added to the Renesis housings and a custom header to accommodate the added ports).

Team, unfortunately I don't think the car will run in STX after the engine build. I would really have liked to have made it out to at least 1-2 SCCA events to run in that class, but I guess it wasn't meant to be (really, it needed to happen last year so that I could then move on to a more extensive build plan). I will definitely make it out to some events once my achilles is all healed up (so I can heel & toe again!), but that probably won't be until August or Sept. Hope to make it out to some local events before that, tendon permitting.
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Old May 26, 2011 | 09:54 AM
  #277  
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Hey Dave,
Sorry to hear about the tendon and all. Can't be fun not being able to drive at all, I know I'd be going crazy for sure. Just have been following your build a little bit here and there, and saw that since you're not thinking of doing STX, are you thinking of doing that supercharger build you mentioned before then? Perhaps turning it into an SM car?

Was just curious is all! I'm sure you're all set in terms of ideas and resources, but if I can help at all, feel free to let me know or check out my blog for some DIYs or something. I always love to see different RX-8 builds with the intention of racing the car at the speed of light
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Old May 27, 2011 | 02:51 PM
  #278  
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Thanks Zelse, the tendon is healing up pretty nicely. I should be walking in a shoe again on June 7th, so getting there. It is killing me not being able to drive the 8 (though I've been left-footing it in the wife's auto Honda...LOL), but it's killing me even more that a HKS dog box that my buddy Joe was going to buy (and I was going to steal from him for the 8...LOL), slipped through his fingers. Ah well, gives me an excuse to go the World Time Attack Challenge in Australia later this summer and pay a visit to the boys at Hollinger.

With respect to autocross classing, the engine build is going to be extreme enough that we may end up in SM, which is fine by me. Really, I just want to get out to some Solo 2 events and hopefully the Nats as a way of promoting this type of motorsport to the mag's readers. We tend to focus a lot on Time Attack and Drift, but in my estimation Solo 2 is really the best place to get your motorsports feet wet, given how affordable, fun and accessible it is compared to just about any other type of racing out there. Plus it's highly competitive if you want it to be, and can teach you a lot about car control and car setup, both skills that'll translate well to other types of motorsports. Not to mention you meet a lot of great people autocrossing -- many of my best friends are people I met racing.

Still undecided on whether to go s/c or turbo, but I think we'll probably go with a custom turbo setup since we're building an engine that can take a lot of pressure and rpm. Will probably build around a BorgWarner EFR series turbo. If I do the peripheral port Renesis housings with Goopy, then a uber complicated custom manifold will have to be fabbed up, but that'll be a fun and challenging project. Eventually I'd really like to go 20b or even 4-rotor with a custom crank and two Renesis joined together (world's first 4-rotor Renesis, maybe?), but those are definitely longer-term ideas. Short-term I want to explore the potential of the Renesis as much as I can, with the help of guys like my engine builder Joe (who kidnapped my RX-8 and took it to the Deals Gap Rotary Rally), the Jims from Racing Beat and Jonathan from Goopy Performance.

Last edited by Modified Dave; May 27, 2011 at 02:54 PM.
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Old May 27, 2011 | 05:26 PM
  #279  
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I will order a lifetime subscription for me and everyone in my family (none of which like cars) if you do a 4 rotor renesis build.
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Old May 28, 2011 | 02:21 PM
  #280  
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Originally Posted by 8upbad
I will order a lifetime subscription for me and everyone in my family (none of which like cars) if you do a 4 rotor renesis build.
LOL...I like your style, 8upbad
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Old May 29, 2011 | 02:11 PM
  #281  
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Thumbs up

Originally Posted by Modified Dave
LOL...I like your style, 8upbad
Same here. It's nice to see some outside of the box thinking about the rotary.
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Old Jun 1, 2011 | 11:25 AM
  #282  
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Bought a Modified Mag while on base a few weeks ago here in Djibouti, Africa and came across your article. I didn't even know Modified had a project rx8, and now that I do, I'm going to have to stay up to date! I'm currently in the process of spending crazy money on a turbo set up, so I'm very interrested in the future articles. Keep up the good work, and can't wait to see how she comes out! I'm also planning on flooding your Reader's Rides when I get mine done :D

-Kris
P.s. I'm considering a few parts, such as an upgraded fuel pump and BC Racing ER's, from mention in your article!
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Old Jun 2, 2011 | 04:48 PM
  #283  
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Originally Posted by bcsoswat07
Bought a Modified Mag while on base a few weeks ago here in Djibouti, Africa and came across your article. I didn't even know Modified had a project rx8, and now that I do, I'm going to have to stay up to date! I'm currently in the process of spending crazy money on a turbo set up, so I'm very interrested in the future articles. Keep up the good work, and can't wait to see how she comes out! I'm also planning on flooding your Reader's Rides when I get mine done :D

-Kris
P.s. I'm considering a few parts, such as an upgraded fuel pump and BC Racing ER's, from mention in your article!
Cool Kris, lemme know when you're ready for a Reader's Ride feature and I'll see if I can make that happen for you. What kind of turbo setup you working on?

The BHR fuel pump upgrade is a no-brainer...uses a 255lph Walbro and drops right into the tank. Easy-peasy install with the BHR loaner tool for removing the ring that holds the pump in the tank (though you could certainly get the ring off with some sort of home-made tool, maybe just a hammer and a screwdriver to tap the ring loose).

The BC coilovers are a great street setup with the off-the-shelf spring rates. For motorsports use they're not ideal, but definitely a very nice street setup since they have a sporty ride quality that is firm but not kidney-punishing and allow you to set the ride height however you like (not to mention the price is right).
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Old Jun 4, 2011 | 06:40 AM
  #284  
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I'd be happy with just a picture of my car in your mag haha.
I'm currently doing a payment plan with Esmeril Racing, and getting their HP 4.0 kit with BB turbo. (Which I had to read what I was actually buying to notice it includes a fuel pump... oops )
Also purchasing a MicroTech EMS, Esmeril Apex Seals, SnowPerformance or AEM Water/Meth Injection (Which ever's better), Okada Projects Direct Plasma Coils (When I find them for a better price), and a ACT HDG6 clutch with ProLight Flywheel to handle all the power. Might as well have the engine ported while I'm at it, right? I plan on swapping my Unorthodox Racing Pulleys, along with my Agency Power 3in cat back from my current 8 into the "new car" when I find a White 06 Shinka to my liking.
I definitely want to go for all quality on this project, mainly to prevent all the money I'm spending from going up in flames

In reference to the Coilovers, are you referring to the version of BC Racing's that you have installed? I was looking at their ER model which includes a external reserve, hence the ER, and thought those would be a step up?
I was planning on getting KW V3's, but I have heard there are better products out there, such as the BC ER's.

Who knows, I'm probably wrong haha.
Thanks for the feedback
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Old Jun 4, 2011 | 05:31 PM
  #285  
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Originally Posted by bcsoswat07
I was planning on getting KW V3's, but I have heard there are better products out there, such as the BC ER's.
This is flat out wrong lol.

BC ER is quality for the price. KW V3 is quality at any price. Not a direct comparison IMO.

Standard BC coilovers, at about half the price of the V3's, will also be fine for the average daily driver that does not see the track.
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Old Jun 4, 2011 | 05:31 PM
  #286  
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Originally Posted by bcsoswat07
Also purchasing a MicroTech EMS
Suggest you do some research before pulling the trigger on that
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Old Jun 4, 2011 | 09:16 PM
  #287  
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Originally Posted by bcsoswat07
to prevent all the money I'm spending from going up in flames
Oops. Too late.

Probably shoulda done some research before you started that lay-away plan.
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Old Jun 5, 2011 | 02:07 PM
  #288  
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Well I would have just built my own kit, but it definitely would have blown up haha.
I guess it's back to research... at least my car will look good when it's done, right?
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Old Jun 5, 2011 | 02:40 PM
  #289  
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Dave, think you're gonna make it to nationals this year? I live about 2 miles from the area and would like to come pick your brain. I read in the last article in modified that you were considering forced induction. I was wondering if you know which class this would throw you into? SM or SSM? The RX7 guys dominate (rightfully so) SSM and I'm just not sure what class you'll be in with boost and a street port. SSM is generally reserved for cars with 2 doors and 2 seats, so I'm pretty sure you'd be in SM. Just wondering if you know.

I'm considering picking up an rx8 for STX myself. I depowered the steering rack on my FD which is gonna make autox corners a bitch.

Kyle
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Old Jun 6, 2011 | 10:21 AM
  #290  
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Originally Posted by bcsoswat07
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Well I would have just built my own kit, but it definitely would have blown up haha.
I guess it's back to research... at least my car will look good when it's done, right?
Man, this forum can be harsh sometimes. Hah.

I'm not too sure what the drawbacks are to the MicroTech EMS, but both Brettus and MazdaManiac are guys who could answer that for you and make alternative recommendations.

I would take a pass on the Okada coils (I've tested them and had mixed results at best). I think you'll find the BHR coils to be a more robust setup, given that they're based on the bulletproof GM coils that are widely used and proven reliable both on street cars and race cars.

I have the base model BR coilovers from BC Racing. I would have opted for the ER if it was available for the RX8, but that wasn't an option when I ordered mine. Looks like they've added pricing to their application list for the ER kit now, and from what I've read the ER kit is well liked, especially by the Subaru crowd. I have no way of knowing how the ER kit for the RX8 will compare to the KW V3's, but I can tell you that the V3's are an excellent product (love the fact that the bodies are stainless steel, so never rust), having run them on several different cars over the years. Here's a couple of links showing V3 testing I did on my G35 and on my buddy's Integra Type R:

G35 story + video:
http://g35driver.com/forums/brakes-s...rack-test.html
http://www.vimeo.com/4483558

Type R story and video:
http://www.tune2win.com/index.php/pr..._3_track_test/

IF the ER coilovers use the same relatively short rear dampers and top mounts, then they're going to suffer from the same lack of travel issue I've had with my BR series coilovers (bottoming out during hard cornering at the track...never been a problem on the street, but I don't drive like a dbag on the street). If BC has used a taller top mount (like the OEM setup) and a longer shock/spring combo, then the rear travel issue shouldn't be a concern.

I will say I have yet to find a coilover system I like more than the KW V3s at that price point, but I haven't tried some of the newer options like AST, Moton StreetSport or the ER stuff from BC.
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Old Jun 6, 2011 | 11:29 AM
  #291  
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Originally Posted by KKMpunkrock2011
Dave, think you're gonna make it to nationals this year? I live about 2 miles from the area and would like to come pick your brain. I read in the last article in modified that you were considering forced induction. I was wondering if you know which class this would throw you into? SM or SSM? The RX7 guys dominate (rightfully so) SSM and I'm just not sure what class you'll be in with boost and a street port. SSM is generally reserved for cars with 2 doors and 2 seats, so I'm pretty sure you'd be in SM. Just wondering if you know.

I'm considering picking up an rx8 for STX myself. I depowered the steering rack on my FD which is gonna make autox corners a bitch.

Kyle
Kyle, I'll either be at the Nationals or Targa Newfoundland, depending on how things line up. Will let you know once the date is a little closer.

The 8 goes to SM once you add FI, since BSP doesn't permit it (rule 15.10.4.C). Same goes for water/meth systems (15.10.C.2). The lightened Racing Beat rotors I'm using in the engine build also bump the car to SM (15.10.T). The beauty of SM is that it's relatively unrestricted as far as mods go, but the downside is that to build a competitive SM car I'd have to gut my 8 out pretty aggressively, which I'm really not prepared to do at this point. Still, a FI 13b min weight in SM is 2700 lbs last time I checked, so perhaps I can get the car down close to that number without having to do anything too radical re: weight reduction. In any case, my build will not be a truly optimized SM machine, but rather a compromise between a street car, a time attack car, and a autox car. Jack of all trades, master of none. But that's ok, I'll still have fun and learn a lot about this car in the process (and hopefully pass along a few lessons in the process).
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Old Jun 6, 2011 | 02:32 PM
  #292  
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Originally Posted by Modified Dave
Man, this forum can be harsh sometimes. Hah.

I'm not too sure what the drawbacks are to the MicroTech EMS, but both Brettus and MazdaManiac are guys who could answer that for you and make alternative recommendations.

I would take a pass on the Okada coils (I've tested them and had mixed results at best). I think you'll find the BHR coils to be a more robust setup, given that they're based on the bulletproof GM coils that are widely used and proven reliable both on street cars and race cars.

I have the base model BR coilovers from BC Racing. I would have opted for the ER if it was available for the RX8, but that wasn't an option when I ordered mine. Looks like they've added pricing to their application list for the ER kit now, and from what I've read the ER kit is well liked, especially by the Subaru crowd. I have no way of knowing how the ER kit for the RX8 will compare to the KW V3's, but I can tell you that the V3's are an excellent product (love the fact that the bodies are stainless steel, so never rust), having run them on several different cars over the years. Here's a couple of links showing V3 testing I did on my G35 and on my buddy's Integra Type R:

G35 story + video:
http://g35driver.com/forums/brakes-s...rack-test.html
http://www.vimeo.com/4483558

Type R story and video:
http://www.tune2win.com/index.php/pr..._3_track_test/

IF the ER coilovers use the same relatively short rear dampers and top mounts, then they're going to suffer from the same lack of travel issue I've had with my BR series coilovers (bottoming out during hard cornering at the track...never been a problem on the street, but I don't drive like a dbag on the street). If BC has used a taller top mount (like the OEM setup) and a longer shock/spring combo, then the rear travel issue shouldn't be a concern.

I will say I have yet to find a coilover system I like more than the KW V3s at that price point, but I haven't tried some of the newer options like AST, Moton StreetSport or the ER stuff from BC.

I don't know how you made it in the Columnist world... haha.
Thanks for the great info. I'll stay posted.
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Old Jun 7, 2011 | 11:25 AM
  #293  
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Originally Posted by Modified Dave
Kyle, I'll either be at the Nationals or Targa Newfoundland, depending on how things line up. Will let you know once the date is a little closer.

The 8 goes to SM once you add FI, since BSP doesn't permit it (rule 15.10.4.C). Same goes for water/meth systems (15.10.C.2). The lightened Racing Beat rotors I'm using in the engine build also bump the car to SM (15.10.T). The beauty of SM is that it's relatively unrestricted as far as mods go, but the downside is that to build a competitive SM car I'd have to gut my 8 out pretty aggressively, which I'm really not prepared to do at this point. Still, a FI 13b min weight in SM is 2700 lbs last time I checked, so perhaps I can get the car down close to that number without having to do anything too radical re: weight reduction. In any case, my build will not be a truly optimized SM machine, but rather a compromise between a street car, a time attack car, and a autox car. Jack of all trades, master of none. But that's ok, I'll still have fun and learn a lot about this car in the process (and hopefully pass along a few lessons in the process).
Thanks for the info. I knew aftermarket FI throws any car into at least SM/SSM, just wasn't sure which way the rx8 went. I know quite a few ST or SP guys run auxiliary injection with washer fluid and get away with it, just an fyi. You should be able to get the car to 2700lbs without too much hassle if its a non-sunroof car. Start by pulling the stereo headunit (if its not too much of a paint) the cruise control module in the engine bay (if its a cable) and all the speakers if its not too hard. I know my fellow FD guys have pulled a/c (I won't) and some of the carpet, and they all have lightweight seats and a fuel cell. I know Erik (20B FD)nearly went under the weight limit two weeks ago at the pro-solo/tour because he forgot to fill his gas tank all the way. In your engine build are you gonna stick with the side exhaust ports or do you think you might go to a peripheral exhaust port like earlier 13bs?
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Old Jun 7, 2011 | 06:00 PM
  #294  
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it's not as easy as you think given the limitations of the SM rules and the "everything is already lightweight from the factory" reality of the RX-8, what little gains you get from AC/rear seat/stereo will be offset with your turbo setup, bigger wheels/tires, etc. You will likely still need custom parts similar to what I have in STX to get there
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Old Jun 16, 2011 | 12:25 PM
  #295  
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Originally Posted by TeamRX8
it's not as easy as you think given the limitations of the SM rules and the "everything is already lightweight from the factory" reality of the RX-8, what little gains you get from AC/rear seat/stereo will be offset with your turbo setup, bigger wheels/tires, etc. You will likely still need custom parts similar to what I have in STX to get there
I'm sure you're right, Team. I've got a brake company that says they're working on a kit for the RX-8 that'll save 40 lbs, plus I've got some pretty sexy seats that'll save another 26 lbs. It's a start. Love what you did with the rear upper shock mounts, so may have to take (another) page out of your playbook on that one. But then I'll be adding some weight with a rear wing, side skirts and some sort of forced induction setup, not to mention I'm thinking about a roll bar. Ugh. 2700 lbs seems a long way away. Ah well, definitely a goal worth working towards, but hopefully it won't require a bunch of dry carbon and a second mortgage
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Old Jun 22, 2011 | 11:35 AM
  #296  
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Originally Posted by Modified Dave
I'm sure you're right, Team. I've got a brake company that says they're working on a kit for the RX-8 that'll save 40 lbs, plus I've got some pretty sexy seats that'll save another 26 lbs. It's a start. Love what you did with the rear upper shock mounts, so may have to take (another) page out of your playbook on that one. But then I'll be adding some weight with a rear wing, side skirts and some sort of forced induction setup, not to mention I'm thinking about a roll bar. Ugh. 2700 lbs seems a long way away. Ah well, definitely a goal worth working towards, but hopefully it won't require a bunch of dry carbon and a second mortgage
I subscribe and read your magazine, great stuff.

Brakes: I dont see 40lbs coming out of the brakes. You can lose 8lbs out of the front with stock sized 2 piece rotors and another 5 from the rear. = 13lbs.

With the calipers the stock fronts with pads and brackets feel very heavy but they are only 13 pounds, rears are 9lbs. A 4 piston aluminum caliper with bracket and pads will weight 6-7 pounds. So you can average it out to 13 pounds out of the front calipers. Rear calipers if you ditch the ebrake and use a 2 piston aluminum caliper you might be able to do brackets, caliper and pads for 5lbs. So thats another 8 total. Grand total of 34pounds removed from the brakes. Thats great but my point is 40lbs wont happen. Be happy with 30lbs. If you do a BBK, you might be able to lose 20-25lbs. Stock brakes with track pads are great, stock brakes with 2-piece rotors and track pads are fantastic, use aluminum calipers to save more weight and you have the best brakes possible on this car. Dont ruin it with a giant brake setup.

Seats. Stock cloth seats with brackets and airbags only weigh 35-38lbs. You cant loose 26 pounds per seat, 26 as a set is still not easy. Must be a lightweight fixed seat and custom fixed aluminum mounts.

2700 pounds is very doable even with a turbo setup, but it will have to be a stripped out car. Not counting stripping the car, brakes, 17" lightweight racing wheels, race tires, exhaust and battery are the easiest places to remove weight. Lexan windshield and rear glass can save some weight but at a heafty price tag. If you go that route, PM me and I might get a set too, maybe work me into a package deal.

Rear wing. I use the APR GTC-200 wing with RX8 mounts and a gourney flap. Team might have one collecting dust, maybe he wil give you a good deal on it.

Subscribe to the "weight of stock rx8 parts" thread. Its a good resource when looking to loose weight. https://www.rx8club.com/rx-8-racing-25/weight-stock-rx8-parts-81791/
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Old Jun 23, 2011 | 09:33 AM
  #297  
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Originally Posted by Highway8
I subscribe and read your magazine, great stuff.

Brakes: I dont see 40lbs coming out of the brakes. You can lose 8lbs out of the front with stock sized 2 piece rotors and another 5 from the rear. = 13lbs.

With the calipers the stock fronts with pads and brackets feel very heavy but they are only 13 pounds, rears are 9lbs. A 4 piston aluminum caliper with bracket and pads will weight 6-7 pounds. So you can average it out to 13 pounds out of the front calipers. Rear calipers if you ditch the ebrake and use a 2 piston aluminum caliper you might be able to do brackets, caliper and pads for 5lbs. So thats another 8 total. Grand total of 34pounds removed from the brakes. Thats great but my point is 40lbs wont happen. Be happy with 30lbs. If you do a BBK, you might be able to lose 20-25lbs. Stock brakes with track pads are great, stock brakes with 2-piece rotors and track pads are fantastic, use aluminum calipers to save more weight and you have the best brakes possible on this car. Dont ruin it with a giant brake setup.

Seats. Stock cloth seats with brackets and airbags only weigh 35-38lbs. You cant loose 26 pounds per seat, 26 as a set is still not easy. Must be a lightweight fixed seat and custom fixed aluminum mounts.

2700 pounds is very doable even with a turbo setup, but it will have to be a stripped out car. Not counting stripping the car, brakes, 17" lightweight racing wheels, race tires, exhaust and battery are the easiest places to remove weight. Lexan windshield and rear glass can save some weight but at a heafty price tag. If you go that route, PM me and I might get a set too, maybe work me into a package deal.

Rear wing. I use the APR GTC-200 wing with RX8 mounts and a gourney flap. Team might have one collecting dust, maybe he wil give you a good deal on it.

Subscribe to the "weight of stock rx8 parts" thread. Its a good resource when looking to loose weight. https://www.rx8club.com/showthread.php?t=81791
Thanks for all the feedback, Highway8!

On the brake weight loss, apparently a good amount of the savings are in the calipers this kit is going to use. I don't have a lot of details on it yet, but will post it up once the manufacturer is ready to release that info. Would be very happy to pull 30 lbs out of the braking system, even if the claimed 40 lbs doesn't prove to be accurate.

My car does have the stock cloth seats, so when I say 26 lbs I mean total (13 lbs per seat), since the Cobras I'm going to run + seat rails will come in at around 25 lbs each.

For a wing, I have a DJ Racecars (http://www.djracecars.com/) wing on the shelf that needs a good home, though I'd have to fab up some custom mounts and uprights if I decide to install it on the 8. But Plan A is to run a Kognition wing with their chassis mount kit. It's a really nice design that mounts the wing right to the chassis in the trunk. Same wing Kyle Mohan runs on his Formula D RX8:

http://www.kognitiondesign.com/mazda.html

I was thinking some 17x10 RPF1's + Hoosiers will save quite a bit of weight over my current setup. I'll have to do the math on that one when I get a chance. Don't think I'll go the lexan route though, since I want to keep this car street legal (at least for now).

I'm well acquainted with that "stock parts weight" thread, thanks. Been digging thru that thread since the day I bought my 8

BTW Highway8, just read your ProCharger thread. Very interesting stuff in there re: cooling, a topic that's on my mind a lot these days since I'm planning to go FI later this year. Enjoyed your Thunderhill videos too -- I've done the 25hr race a bunch of times, so know that track pretty well (though it still looks weird to me in the daylight! Haha). Last time I was there it was in this tasty little pocket rocket (2:04 lap times):

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Last edited by Modified Dave; Jun 23, 2011 at 10:35 AM.
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Old Jun 25, 2011 | 02:41 PM
  #298  
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Originally Posted by Modified Dave
Thanks for all the feedback, Highway8!

On the brake weight loss, apparently a good amount of the savings are in the calipers this kit is going to use. I don't have a lot of details on it yet, but will post it up once the manufacturer is ready to release that info. Would be very happy to pull 30 lbs out of the braking system, even if the claimed 40 lbs doesn't prove to be accurate.

My car does have the stock cloth seats, so when I say 26 lbs I mean total (13 lbs per seat), since the Cobras I'm going to run + seat rails will come in at around 25 lbs each.

For a wing, I have a DJ Racecars (http://www.djracecars.com/) wing on the shelf that needs a good home, though I'd have to fab up some custom mounts and uprights if I decide to install it on the 8. But Plan A is to run a Kognition wing with their chassis mount kit. It's a really nice design that mounts the wing right to the chassis in the trunk. Same wing Kyle Mohan runs on his Formula D RX8:

http://www.kognitiondesign.com/mazda.html

I was thinking some 17x10 RPF1's + Hoosiers will save quite a bit of weight over my current setup. I'll have to do the math on that one when I get a chance. Don't think I'll go the lexan route though, since I want to keep this car street legal (at least for now).

I'm well acquainted with that "stock parts weight" thread, thanks. Been digging thru that thread since the day I bought my 8

BTW Highway8, just read your ProCharger thread. Very interesting stuff in there re: cooling, a topic that's on my mind a lot these days since I'm planning to go FI later this year. Enjoyed your Thunderhill videos too -- I've done the 25hr race a bunch of times, so know that track pretty well (though it still looks weird to me in the daylight! Haha). Last time I was there it was in this tasty little pocket rocket (2:04 lap times):


Brakes:

Your right about the calipers being a big chunk, but your not going to find a caliper, bracket, hardware and pads for the front that weighs less then 6 pounds. 7lbs is very good and light. So I think 30lbs is a good goal. When people estimate the weight they forget to include hardware brackets and pads.

Cooling: I just updated some oil cooling info. Turns out I might not need the second oil cooler. So you could loose some weight by ditching the heavy stock coolers and look into a big single cooler. Either on the drivers side or center mount. If you do a modified crash bar you can center mount a very large stacked cooler and it wont hurt radiator air flow. Plus I think you can remove 8 pounds rom the crash bar and still be safe.

Wing and Aero: The Kognition wing is a nice setup but may be a little overkill for most people. Plus a bit pricy. Unless you do a big slitter in the front you wont be able to take advantage of even a small rear wing. I have a custom front splitter and with my APR GTC-200 rear wing I find I dont need a sharp angle of attack. If I go to aggressive I induce oversteer. At high speed the front end tends to lift so the front needs the downforce. If you add some rack and do a good splitter you can run a mild wing and still be balanced. Plus more wing adds drag and kills the top speed.

Seats I was going to do the Cobra FX1 fied back seat which weighs 16 pounds. Maybe a custom Chromoly mount for strengh and weight. I think 26 pounds total is possible. I went away from the idea for the moment because of cost vs weight loss didnt do it for me and the air bag issue. Have to trick the sensor otherwise you lose all airbags. Thats fine for a track only caged car, but not for my street/track car.

tires and wheels Going with rpf1 17's will save the most weight but you might run into brake caliper clearance issues. 9.5 wide is fine. My 18X9.5 +45 rpf1's wth 275/35 hoosiers fit and work great. I also like the 18's because i can find grandam take offs for cheep. I think the total weight is 38 pounds. I heard the 17's come in at 35lbs.

Thunderhill 2:04 is fast. I think my best is 2:05 with the by-pass while NA on worn out tires and 2:05.5 over the top with 8PSI blower making 255 RWHP. I hope to brake 2 minutes with the by-pass when the blower is dialed in. Over the top maybe 2:02-2:03.

Lexan May not be DOT approved but your local government cant enforce it. Besides caging a car, removing the side air bags and using a harness isnt DOT legal either and you better be carefull where you run the bars or always wear a helmet.

All this stuff makes me want to ditch insurance and registration and make it a full track car. Sub 2700 pounds with 325+ RWHP sounds awsome to me.
Attached Thumbnails Modified Mag RX-8 project car -- STX here I come!-car-trailer.jpg   Modified Mag RX-8 project car -- STX here I come!-cimg0322.jpg  

Last edited by Highway8; Jun 25, 2011 at 02:44 PM.
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Old Jun 25, 2011 | 03:37 PM
  #299  
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you will likely not be able to fit 17" Enkei RPF1 wheels over aftermarket brake calipers unless you build custom rotor hats and caliper brackets to offset them way inboard. I need some kind of ridiculous spacer to get the 17 x9 over my RacingBrake standard size 2-pc brake kit, something like 40mm thick which then puts the offset way out in fender cutting territory

other 17" wheels will clear no problem, just the way Enkei has the spoke/hub arrangement configured

if you build a custom bracket for a rear aluminum caliper you might get to 40 lbs, maybe only 35 lbs total. SCCA rules do require a functional e-brake so you have to do some work regardless. My full RacingBrake front kit/rear rotors is something like 29 lbs total reduction. Since the rear OE calipers and mounts are steel/iron there is some weight there to get rid of, but the rear mount is rather complex configuration to build. Not at all straightforward like the front caliper bracket, which is nothing more than a machined piece of flat plate. The other issue is that while weight reduction is good, removing it off the rear is much less effective overall since once you get into serious weight removal you will find that getting it off the rear is much easier than the front for weight balance purposes. If you can get the car underweight relative to classing rules it will allow you to use ballast in a more effective location. In this case getting the weight off the suspension is a good thing relative to tire control/grip, though you will likely need to address damper valving to make the most of it.


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Last edited by TeamRX8; Jun 25, 2011 at 03:49 PM.
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Old Jun 26, 2011 | 09:06 AM
  #300  
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See if you can find a set of Enkei RC-T4 wheels. As light or lighter and I don't think they have the clearance issues.

Here is a gold set FS http://www.iwsti.com/forums/gr-wheel...5-114-3-a.html

Last edited by Highway8; Jun 26, 2011 at 09:17 AM.
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