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Discussion Starter #1
So this crazy idea has been floating in my mind for a bit: take the supercharger off of my Elise SC and run NA with a tune and possibly a set of cams.

I track a lot and if the Elise isn't seeing track miles, it's seeing canyon miles. Thus, my supercharger sees a lot of repeated high rpm work that the M45 probably isn't designed for. Accordingly, the long term reliability of the supercharger doesn't fill me with confidence. However, I don't really want more power than what I have right now (ludicrous I know) and I like the idea of going back to NA, so I've been thinking of converting the car to NA.

I know most people would just go to another supercharger, such as a Rev300. I know the Rev300 would produce a lot more power and is reliable, but I feel going to NA would offer a few advantages: 1) It should be a few grand cheaper than the full Rev300 kit; 2) There's one less heat source in the engine bay and one less item to worry about failing; 3) I can have consistent power over a track session rather than losing power as the supercharger heat soaks; 4) I just like the thought of being NA.

I think the main disadvantage, for more at least, is that I might lose some midrange, which is undesirable as I'm trying to avoid 2nd gear on track. However, there are a couple dynos floating around that shows that a Piper stage 2 cam with tuning would produce about the same midrange torque and top end power as an Elise SC. I'm not sure if those are accurate. And obviously, there's that feeling that you just paid money to "downgrade."

Anyway, any thoughts on my proposed course of action? I know somebody staged that their BOE Torque200 tune felt faster than their significant other's Elise SC, but that's about the only report I saw.
 

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Less is Better
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Is your car a factory SC? If so, unless you're got a ton of irreversible modifications to your car, you would probably be better off selling the car and buying a NA car. I have the Torque200 and it definitely gives the car more midrange than it had stock and the cam change is barely perceptible which is great IMO. The only SC car I've been in was a built rev400 and that thing was RIDICULOUS so I can't compare my tune to a stock SC.
 

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I had a Torque 200 tune, sounded better, but to be honest, I didn't have the seat of the pants feeling that it was faster. Your mileage may vary. The tune lowered the cam changeover, but in retrospect, I liked how the original kicked in and you felt it. With the tune, you don't feel it as much, you just hear it changeover. Just my preferences. The most annoying thing about the tune was that it didn't always start the first time when engine is cold.

I'd stick with your M45 and just wait till it goes. I'm not sure where you get that it wasn't designed for repeated high rpms. I mean, it's factory right??? If it goes, then you instantly have an NA and then you can decide if you want to go rev300 or not (you definitely will btw). Another way is to lower your weight. Stock battery is 26lbs, I'm selling a 4lb LiFEPO4 battery if you are interested (shameless plug).
 

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Less is Better
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I'm surprised to hear that someone doesn't feel the mid range bump. It was pretty obvious to me. I also have the starting issue and it's annoying. Phil seems to have trouble tracking it down and it doesn't sound like free bug fixes are on the menu.
 

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Discussion Starter #5
Mine is factory supercharged, but I'm very attached to my car and there's just no way I'm selling it. Also, it's got quite a lot of mods to it as well and I've even started to sell off some of the special Final Edition equipment that I've pulled off because I've realized I'm never selling it.

It's a factory supercharger, but even Lotus has stated that the M45 was designed for country road driving and that if you're planning to track it, you're better off with a NA Elise or an Exige. There's been reports of the M45 failing pretty quickly, and mine has been tracked to the point where I'm worrying when it'll fail. And I'm already running a LiFe battery.

As for the cam changeover feel, that's something that is not desirable to me and is definitely something I'd want to eliminate in a NA car. It feels like a lot of fun on the street, but on the track it has the potential to upset the car on corner exit.

I think perhaps goober doesn't feel that the tune is more powerful because there isn't as much of a kick in the powerband as the stock tune, thus the power delivery has less drama. It's like the difference between driving a supercharged car and a turbocharged car. The turbocharged car is just more dramatic.
 

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`08 Elise-SC-220
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LionZoo:

There's been reports of the M45 failing pretty quickly

I've have been looking to hear from another SC driver with the M45 rather than an M62 (most prevalent factory SC in the Exiges) to rap about maint. like changing oil and such. This is probably something you (we) should look into if you operate at "high shrill" a lot. Selling the car and getting a base model has it's point. Really, what have you heard about the Eaton M45's reliability. I'm very interested. I like the set-up myself.
 

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Discussion Starter #7
LionZoo:

There's been reports of the M45 failing pretty quickly

I've have been looking to hear from another SC driver with the M45 rather than an M62 (most prevalent factory SC in the Exiges) to rap about maint. like changing oil and such. This is probably something you (we) should look into if you operate at "high shrill" a lot. Selling the car and getting a base model has it's point. Really, what have you heard about the Eaton M45's reliability. I'm very interested. I like the set-up myself.
http://www.lotustalk.com/forums/f160/2008-elise-sc-failure-need-options-opinions-304154/

Bearing issues seem to be common. Considering Lotus already overdrives the M45, it doesn't fill me with confidence. Especially so because I'm doing about a trackday a month. I think if you just use it for street driving, you're fine.

I didn't want the supercharger, but I wanted a red 2011 (2011 was absolutely a requirement for me) and being offered Final Edition no. 15 was too tempting for me. I'm simply not selling it; it's not a discussion worth having.
 

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I have the Torque 200 and can definitely feel it when the second cam kicks in. My car would not start first try cold, even with the stock ECU sometimes. I purchased some Okada plasma ignition coils and have never had a problem starting, even with the Torque 200. Im sure the Coils have something to do with this. Elise owners have rode in my car and asked if it was a SC. When I tell them no they ask what tune I have.



Sent from my iPhone using Tapatalk
 

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Acme Super Moderator ** The Enforcer **
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I can't imagine giving up the extra torque of the SC, even the small non-intercooled Elise SC. I added 55 rwhp to my Exige S within the first six months of ownership. If anything I'd like more power, but to do it correctly would be very expensive. I've got other toys.

San
 

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Discussion Starter #10
LionZoo:

There's been reports of the M45 failing pretty quickly

I've have been looking to hear from another SC driver with the M45 rather than an M62 (most prevalent factory SC in the Exiges) to rap about maint. like changing oil and such. This is probably something you (we) should look into if you operate at "high shrill" a lot. Selling the car and getting a base model has it's point. Really, what have you heard about the Eaton M45's reliability. I'm very interested. I like the set-up myself.
PS, check out Phil's comments starting at this post and continue reading: http://www.lotustalk.com/forums/f259/elise-factory-supercharger-always-improvement-372930/index2.html#post5019193

Specifically: "Is the SC faster than an NA? Driver's equal, a good running, tuned NA with headers is gonna be faster than an SC by lap 4 on a 90 degree day and gap the SC from there on to end of session. It's not a lot, but I wager it will be faster, simpler, and more reliable--- on the track... There's just not enough boost to make up for the heat. You end up loosing too much air density once the system is at full temp while having the additional burden of spinning the blower."

I had a 2011 Elise R before my current Elise SC and while the extra midrange was very noticeable, I did find that straight line speeds at track were not noticeably higher. As to reliability, notice Phil's explanation that there is no IAT sensor after the supercharger. I do notice a bit of pinging on hot days when running hard, which is why I no longer track the Elise when it's hot.
 

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Acme Super Moderator ** The Enforcer **
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Forced induction without an intercooler doesn't make any sense to me. I would add that an efficient intercooler is even more important.

San
 

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Most owners I have talked to find themselves pushing the car less hard when SC'd because the power is more accessible. The reality is they spent a lot of money to still not USE more than 190hp, which to me is a waste. I love thrashing my NA and wringing its neck. I'll go on some drives with Viper and GTR types, and the interstate is the only time the power disadvantage shows up, and I am not terribly upset about that because I am fond of my license, haha. On track, my skill level is so low there's no hope of an SC making me faster anyways.

Funny enough though, my car was previously SC'd. The original owner sold off all the upgrades when he totaled it.
 

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`08 Elise-SC-220
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LionZoo: "I do notice a bit of pinging on hot days when running hard, which is why I no longer track the Elise when it's hot." It's been stated that High octane gasoline is critical with the SC setup. I don't use that 10% ethanol "warm beer" and even blend (non-ethanol) 93 pump octane with 20% (1 gal to 4) unleaded race gas for a pump octane value of 95 (98 RON). It gets plenty hot here in FL in August and the cooling system only keeps up when the car is moving. I can hammer the heck out of the car on the Interstate and it just loves it. Furthermore, when I back off the car (at an exit) and coast to a stop, it just purrs like a kitten. I hesitate to take the car on any long trips where I don't have access to pure fuel. JMHO.
P.S. I always treat my "soup" with Stable fuel stabilizer to keep it fresh in the can and in the tank since I always have more fuel "sitting" than I use in a 30 day period.
 

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Discussion Starter #14
I agree that, for street use, the supercharger makes sense as as I think it matches the typical use case very well. However, the use case I'm building towards is tracking, which is very different than street driving as that's 20-25 minutes of continuous full throttle applications. Furthermore I'm running times, on street tires, that would put me midpack in Lotus Cup, where they run racing slicks. I'm continuously finding the weakest link in the car and the last couple times it's been the transmission. With the transmission strengthened, I think the supercharger might be next...
 
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