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I’ve been working on heavily researching what to do for an 06-07 Elise SSM-class autocross build. For the power portion of the build, I’m concerned with the engine build, supercharger kit, transmission, fuel system, and ECU. I’m aiming at around 380-400rwhp, with an emphasis on low to midrange torque (3-5k).

From my research so far, it seems like the following basic setup is what I want to do:
* Full motor build – sleeves, 9:1 pistons, head gasket, ARP everything, good rods/wiseco pistons, head porting, valve springs/retainers, etc. Keep the rev limit at 8500 for safety.
* Header/Exhaust - Which header to use is a bit unclear. MWR suggests the PPE header. A major concern is that I need to be able to stay well below 92dB at 50 ft for several of the places I race, leading me to believe that I may need both a very quiet exhaust and a cat.
* Supercharger kit – The Rev400TVS seems like the only thing that’ll get me up to the power levels I’m looking for. I’m guessing I’ll need 18-20ish psi with a lower compression motor build? Looking at the compressor map for the R1320, I'll probably need ~1050-1100 m^3/hr, at ~2.2-2.4 pressure ratio. The R1320 will do it, but it starts getting out of the sweet spot. I wish someone made a supercharger kit using a Whipple... The 100AX 1.6L unit I'm using on my Miata would be in such a great place for this build on the Lotus...
* Fuel system – On my Miata, I’ve been using E85, but I’ve heard that the Elises have some issues with cylinder washing with it. I’d be happy to do 400rwhp with pump gas if it’ll work, I just don’t know how knock-sensitive these motors are -- it seems likely that it's getting sketchy at that point. If I can do it safely on pump, then I probably only need to get ~750cc injectors. For E85, I’ll need 1100s or so. At that level of flow, I assume that a modified stock rail won’t work, I should go with something like MWR's full rail kit? And I should probably aim at the Deutchwerks 300/320 fuel pumps?
* Transmission – Autocross does lots of drag race-style launches, which has been known to pop C6x boxes and axles like candy. As such, I’m looking at likely doing the E153 conversion kit. I’m sad that there’s no OS Giken option for the box, though, since I’ll probably have to spend time figuring out how to tune a Kaaz unit. Does this seem like a logical conclusion to everyone?
* ECU – This is one of the points I’m struggling most with. The car will be street driven as well, so I need to retain emissions legality (one way or another). This appears to mean that I’m limited to either the Fastworks tunes or going with a standalone and switching back to the stock ECU for emissions, which doesn’t seem likely to work very well. I could probably do something like get a one-off fastworks tune with MIL defeat for the stock ECU that I one time flash, and then can swap back to that once every 2 years. In general, my needs for engine management aren't huge -- I just need enough control over fuel/spark to make my power levels work and transition well. It'd be a huge bonus if I could do Flex Fuel, since E85 access is weak around here, and having to fully drain the tank/switch maps is a royal pain in the ass. I'm also hoping to reuse my EVO4/MyChron3 data system/dash from the current SSM car, so anything that use that is good. I have a RaceLogic traction control system I can throw in as well, but if one of the engine management solutions have good enough built-in TC to use for national level autox, that'd be a nice bonus too. EPTuning/DRS/PIP all seem to do most of these things, except that none of them seem to be emissions compliant. Is there anything I'm missing here?

I have most of this all documented in various places on my wiki, if anyone wants to help follow along/see my thoughts. :)

Engine: Engine - Destination SSM 2 - The Elise
Drivetrain: Drivetrain - Destination SSM 2 - The Elise
ECU: Electronics - Destination SSM 2 - The Elise
Other stuff from the main page: Destination SSM 2 - The Elise
 
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