Sunday, November 19, 2017

Replacing the CMC, Adding Power and Dropping Weight

After the last event, I noticed on my way home that the transmission was starting to feel really notchy and then last week while driving Lupa around, I suddenly couldn't disengage the clutch to change gears. I noticed that the clutch fluid reservoir was really low and friends on the faceballs suggested it was likely a leaking clutch master cylinder.

New OEM Clutch Master Cylinder - 11-19-2017
Part numbers for refence - 11-19-2017

I ordered both a new clutch master and slave cylinder and today I went to SJF Performance to replace them. Removal of the old CMC immediately revealed the leak. Thankfully it was a slow leak and I was able to simply top off the reservoir in order to drive the car to the shop. The new CMC bolted in pretty easily minus the finicky nut that goes in the footwell near the ECU. You could just barely fit a deep socket in there to loosen it up.

Leaking CMC - 11-19-2017
Although there was no leak in the slave cylinder, I opted to replace both as a precaution. With both replaced, there was obviously a ton of air in the system that needed to be bled out. To speed this up, SJF used the cap of my old CMC to fabricate a way to pump in some compressed air to help push the fluid through. It only took a few minutes to fully bleed the system using this method. We also flushed the trans fluid since it's been a while since I last had it done. The clutch is now nice and firm and the shifts are once again buttery smooth as one would expect from an S2000. 

New OEM Clutch Slave Cylinder installed - 11-19-2017
With Rad moving ahead with his part out plan, I decided to fix the one issue that's been nagging me about Lupa since I build her for STR. Having driven both my car and Rad's, his car always had an obvious power advantage. This is mostly due to me having an exhaust setup that's more designed for a sporty feel and sound on the road than straight up maximum race performance. Rad's car had a Toda Torquie-Kun header (the same that I installed in Bumblestook earlier this year) ceramic coated by JetHot mated to a 70mm Berk high flow cat and a 70mm T1R 70R-EM stainless steel exhaust and a dyno tune by Karcepts on his Greddy EManage Ultimate EMU. I jumped on the opportunity and grabbed his Toda Header and his Greddy EMU. However, I instead opted to pick up a new 70mm Evasive Motorsports high flow cat and full titanium 70mm T1R 70R-EM exhaust from Clyde's never-realized STR build. 

Old PLM header top / New (to me) Toda header bottom -  11-19-2017
Berk HFC top / New EVS HFC bottom - 11-19-2017
T1R 70R-EM Titanium - 11-19-2017
This would ensure that the tune on Rad's Greddy EMU would give the same performance from what I felt on his car. The reason for getting the titanium exhaust was simple...weight. The T1R 70EM in Titanium weighs only 14lbs, a 20lb reduction over my 34lb titanium dual tip Mugen exhuast. 

Rad's Greddy EMU with dyno tune (left) /
My old Greddy EMU with Karcepts reflash (right)
The install was of course very straight forward although the Innovative 75A motor mounts on the car blocked the Toda header from just slotting in unlike the old PLM header. SJF had to remove the passenger side mount in order to get it in. After swapping the EMUs and recalibrating the TPS voltages, we were able to fire her up. I took her for a test drive and the low end power is very impressive. It's exactly the missing mid/lower power I felt Lupa was missing all this time and the exhaust sounds pretty good too though quite a bit deeper and louder than my Mugen exhaust.

T1R exhaust installed - 11-19-2017
EVS 70mm HFC installed - 11-19-2017
Toda Torquie-Kun header installed - 11-19-2017
I'm super glad that the clutch and transmission feels great again and the new power mods are going to be a big help next year. The only thing left for next season is switching up the tires to BFG Rival-S 1.5 instead RE-71R. For now she's back to riding on stock wheels with Continental DWS for the winter.

Side note: I also replaced the nasty 2-year old air cabin filter with a new one from Rad's S2000 parts stash.

New air cabin filter - 11-16-2017