My 20B racecar thread
#1
Thread Starter
****** of disaster
iTrader: (1)
Joined: Aug 2001
Posts: 1,115
Likes: 0
From: Santa Monica, CA
My 20B racecar thread
Everyone else seems to have a thread so I'm starting my own!
As some of you may know, I have recently (sort of) completed a 20B turbo FC racecar. This car used to be an SCCA EP car which I turned into a super duper time attack/super unlimited car. Buildup thread is here: https://www.rx7club.com/20b-forum-95/my-20b-fc-roadrace-car-underway-663170/
I'm going to treat this as a sort of blog of my adventures as I usually learn alot during the process of building, rebuilding, and modifying this thing and would like to share.
So...
First up, brakes. I've been out testing with the car a couple of times and have mixed success with the brakes. First of all I am an idiot and had the brake master cylinders the wrong way around on my Tilton pedals. After I fixed that, braking was 'decent' I would say but not quite where I thought it would be. I was using the stock FC 4-piston calipers and rotor with Hawk blue pads. After the last session, here are the results:
So I decided to go on an upgrade path...a few people had replicated the old K2RD setup using the Wilwood 6-piston calipers including flynbryn on here who kindly gave me all the part numbers. But then I stumbled on a thread by Project7 on here where he had successfully fitted the Brembo calipers from the Evo to the FC spindles. The Evo rotor at 12.8" is bigger than the Wilwood setup, and not having to make a caliper bracket was a huge plus for me. So, following Project7's lead I picked up a set of Brembo calipers locally and set to it. Results are pretty glorious:
After consulting Tilton, they suggested using a 13/16" bore master cylinder for the front which arrives today. I'm hoping the increased pad area, rotor diameter and rotor thickness is going to be great for the car.
Next up, my RE-Amemiya wing had split in half the last time I used it. Not exactly what I was expecting from a $1500 wing, but still a problem I had to deal with nevertheless.
After a week of repairs, the wing was as good as new and I'm assured won't crack again. Thanks to Dave at ShineAutoProject for repairing it for a great price and doing an awesome job!
Next up I replaced the JIC coilovers. I really hated how these things felt on the track and was pretty pleased when I found out that RX-Heven was offloading lots of cool suspension pieces from his old FC project, including a set of double adjustable Koni coilovers built by Tri-Point. These are pretty cool pieces and have to be custom made due to the fact that there is no rear double adjustable shock made by Koni which fits the FC; they take a single adjustable sport rear and modify it to be double adjustable, pretty cool. I now have these on the car:
I'm going to be trying 650lb front and 400lb rear springs and will take it from there. This is a significant increase in spring rate as I previously ran 450lb front and 325lb rear. I felt the car was a little sloppy before and hopefully this will help.
I also upgraded the front control arms to the needle-bearing version AWR makes. They replace the bushings on the front control arms with needle bearings which eliminates binding - the difference in ease of motion is really incredible and I can't wait to feel how these are on the track! I also replaced the rear trailing arm outer pickup point with the bearing-ized version AWR sells - the stock bushing design used in conjunction with the AWR individual camber adjusters seems to be twisting and not moving quite as freely as it should, so this should help significantly.
And lastly for now, new brakes calls for new wheels! The Brembo's protrude from the hub about 2" so the old 16" steel wheels I had weren't even close to fitting. My favorite wheels ever are the CCW classics which I used to have on my old Z, so I picked up some 18x12 rear and 18x11 fronts with Hoosier 335/30 and 285/35 tires. Unfortunately they won't fit under my AWR fenders, so I have the Tri-Point replicas coming which will hopefully do the job. If not I'll have to look into getting RX-Heven's gigantic wide bodykit and trying that.
If all goes well I hope to be on track in the next 2-3 weeks. Just have to get the new fenders on, waiting for the new Hawk pads for the Brembo's, and the usual alignment/cornerbalancing. I can't wait!
As some of you may know, I have recently (sort of) completed a 20B turbo FC racecar. This car used to be an SCCA EP car which I turned into a super duper time attack/super unlimited car. Buildup thread is here: https://www.rx7club.com/20b-forum-95/my-20b-fc-roadrace-car-underway-663170/
I'm going to treat this as a sort of blog of my adventures as I usually learn alot during the process of building, rebuilding, and modifying this thing and would like to share.
So...
First up, brakes. I've been out testing with the car a couple of times and have mixed success with the brakes. First of all I am an idiot and had the brake master cylinders the wrong way around on my Tilton pedals. After I fixed that, braking was 'decent' I would say but not quite where I thought it would be. I was using the stock FC 4-piston calipers and rotor with Hawk blue pads. After the last session, here are the results:
So I decided to go on an upgrade path...a few people had replicated the old K2RD setup using the Wilwood 6-piston calipers including flynbryn on here who kindly gave me all the part numbers. But then I stumbled on a thread by Project7 on here where he had successfully fitted the Brembo calipers from the Evo to the FC spindles. The Evo rotor at 12.8" is bigger than the Wilwood setup, and not having to make a caliper bracket was a huge plus for me. So, following Project7's lead I picked up a set of Brembo calipers locally and set to it. Results are pretty glorious:
After consulting Tilton, they suggested using a 13/16" bore master cylinder for the front which arrives today. I'm hoping the increased pad area, rotor diameter and rotor thickness is going to be great for the car.
Next up, my RE-Amemiya wing had split in half the last time I used it. Not exactly what I was expecting from a $1500 wing, but still a problem I had to deal with nevertheless.
After a week of repairs, the wing was as good as new and I'm assured won't crack again. Thanks to Dave at ShineAutoProject for repairing it for a great price and doing an awesome job!
Next up I replaced the JIC coilovers. I really hated how these things felt on the track and was pretty pleased when I found out that RX-Heven was offloading lots of cool suspension pieces from his old FC project, including a set of double adjustable Koni coilovers built by Tri-Point. These are pretty cool pieces and have to be custom made due to the fact that there is no rear double adjustable shock made by Koni which fits the FC; they take a single adjustable sport rear and modify it to be double adjustable, pretty cool. I now have these on the car:
I'm going to be trying 650lb front and 400lb rear springs and will take it from there. This is a significant increase in spring rate as I previously ran 450lb front and 325lb rear. I felt the car was a little sloppy before and hopefully this will help.
I also upgraded the front control arms to the needle-bearing version AWR makes. They replace the bushings on the front control arms with needle bearings which eliminates binding - the difference in ease of motion is really incredible and I can't wait to feel how these are on the track! I also replaced the rear trailing arm outer pickup point with the bearing-ized version AWR sells - the stock bushing design used in conjunction with the AWR individual camber adjusters seems to be twisting and not moving quite as freely as it should, so this should help significantly.
And lastly for now, new brakes calls for new wheels! The Brembo's protrude from the hub about 2" so the old 16" steel wheels I had weren't even close to fitting. My favorite wheels ever are the CCW classics which I used to have on my old Z, so I picked up some 18x12 rear and 18x11 fronts with Hoosier 335/30 and 285/35 tires. Unfortunately they won't fit under my AWR fenders, so I have the Tri-Point replicas coming which will hopefully do the job. If not I'll have to look into getting RX-Heven's gigantic wide bodykit and trying that.
If all goes well I hope to be on track in the next 2-3 weeks. Just have to get the new fenders on, waiting for the new Hawk pads for the Brembo's, and the usual alignment/cornerbalancing. I can't wait!
Trending Topics
#9
Funny thing is that when I first built the car for EP I bought a set of the TriPoint flares and then replaced them with the Mariah fronts and then the AWR fronts went it was sold. New wheels, much better!
#11
Thread Starter
****** of disaster
iTrader: (1)
Joined: Aug 2001
Posts: 1,115
Likes: 0
From: Santa Monica, CA
Well ****. Got the Tri-Point fenders, but they're too small for the ride height I'm looking for. Guess I am going with RX-Heven's bodykit after all
Once I have the fenders/bodywork sorted out, I think I am all set. Just waiting for the brakepads to arrive and everything should be in order!
Once I have the fenders/bodywork sorted out, I think I am all set. Just waiting for the brakepads to arrive and everything should be in order!
#18
Car looks great! Love the one off brake kit setup. I hope it does actually work without issues.
When you are ready to make 500hp flywheel from an n/a based LS1 on 91 octane let me know. I'm Dave's buddy... trying to convert him over to the dark side too
When you are ready to make 500hp flywheel from an n/a based LS1 on 91 octane let me know. I'm Dave's buddy... trying to convert him over to the dark side too
#19
Thread Starter
****** of disaster
iTrader: (1)
Joined: Aug 2001
Posts: 1,115
Likes: 0
From: Santa Monica, CA
http://www.v8rx7forum.com/v8-rx7-tec...tonwillow.html
Besides, 500 flywheel hp is for girls
Last edited by thetech; 07-17-08 at 05:56 PM.
#20
I'll blow it up real good
iTrader: (1)
Joined: May 2001
Posts: 2,390
Likes: 1
From: San Francisco, CA
Never ever gonna happen.
What, so I can end up like this poor fellow? (sorry Joel)
http://www.v8rx7forum.com/v8-rx7-tec...tonwillow.html
Besides, 500 flywheel hp is for girls
http://www.v8rx7forum.com/v8-rx7-tec...tonwillow.html
Besides, 500 flywheel hp is for girls
#22
Thread Starter
****** of disaster
iTrader: (1)
Joined: Aug 2001
Posts: 1,115
Likes: 0
From: Santa Monica, CA
Behold the black, blue and white monstrosity! And my lord these things are unbelievably wide - in the pics, the right rear (which is 18x12 with 335 tire) has a 1" spacer and theres STILL probably about 2-3" spare. I could fit a 14" slick under here with no problem at all.
Thanks much to RX-Heven for yet another smooth 4 figure transaction
Thanks much to RX-Heven for yet another smooth 4 figure transaction
#25
Wow, I hadn't even noticed your thread. Your car is looking awsome, that body is really gonna look awsome when you paint it, are ya sticking with the same blue? what about the wheels (color)? Good Luck!
BigAl...
BigAl...