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Discussion Starter #1
I wanted to share some of my recent work on my 2zz MR2 Spyder which we have in common. I had posted on here last year with the work on my 1zz then on another spyder that I did with a 2zz.

Unfortunately, I didn't follow up as I got side tracked by ronnin on the other Elise site and answering questions / debating / etc. I guess I kind of figured that you guys had enough options coming your way that there wasn't any room for one more. Also the reception and "tone" of the "debates" I had didn't really bode well as far as holding my interest.

However, in lurking here over time I have seen that you guys are much more open.

So I thought I would at least share what I have done with a 2zz so you can see what is possible. The spyder is light, but the Elise is lighter still and looks like a pure sports car. I've seen the one LR has for the 15k challenge a few times and I have to say, it is making me want one more and more :)

Oh well, I'm not sure what the policy is here on external links but here you go. This is the link to my latest thread that is somewaht abbreviated compared to my 30+ pager from a year and a half ago.

3.0 Racing Rotrex SC - Revisited - #'s pg. 6 - Forums Index
 

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I am surprised that no one has ever tried ordering a Komo-Tec without there ECU solution and then try tuning it with an EFI.
 

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00 MRS - 2ZZ NA
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Get that interest goin WEB :) . As you mentioned in the thread, with a 8,500 rpm rev limit on your new tune, I'd love to see 350 supercharged whp out of a Lotus. That's all forcedfed had to run a 11.3 @ 130 mph with their turbo'd Lotus.

I am surprised that no one has ever tried ordering a Komo-Tec without there ECU solution and then try tuning it with an EFI.
That's because the goal of owning a Lotus is a lifestyle choice rather than eeking out power from a little 4 banger by using standalone ECU's...which is also the reason there are a handful of 190+ NA whp 2zz Toyotas out there and ZERO here ;) . At least you guys are one step closer to hitting those numbers now that the PPE race header came out.
 

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I really hope this catches-on... a Rotrex/Procharger type of blower is much better suited to the high-rpm nature of the 2ZZ.

Be good,
TomK
 

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So web 3.0 builds this 'kit' for the MR2Spyder, what would be additionally needed to transform this MR2-kit into a Elise/Exige kit?

Custom brackets
Intercooler?
???
 

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Discussion Starter #6
ED - it would take very little to port it over to an Elise.

#1 - I would have to look at the front mount Heat exchanger to check dimensions and placement.

#2 - I would have to double check placement of the side mount intercooler.

#3 - Confirm placement of the Rotrex fluid Heat Exchanger.

#4 - Address tuning options

#5 - Double check clearances for the relocated A/C compressor for those with A/C.

As you can see, pretty minor issues to resolve.

I have 4 rotrex'd spyders on the road for the past 1.5 years with no issues, complaints, or problems. Not to mention the fact that I have 1st hand experience with pretty much every FI option you can think of on the zz motors.

I would love to find a Houston based Lotus that needed a Rotrex. I know what 300 RWHP feels like in my car. I know how controllable and smooth the power delivery is and how I can maintain traction with my 215's and LSD on the rear. Having the same setup in an even lighter car would be simply incredible!

I can routinely make 225 - 250 RWHP on a 1zz and 300 - 325 RWHP on a stock 2zz!
 

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Web,

Thanks for the posting and link. Nice work! I have a simple-minded question: why isn't the torque curve flat like we see with other supercharger alternatives?

Thanks,

Joe
 

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ED - it would take very little to port it over to an Elise.

#1 - I would have to look at the front mount Heat exchanger to check dimensions and placement.

#2 - I would have to double check placement of the side mount intercooler.

#3 - Confirm placement of the Rotrex fluid Heat Exchanger.

#4 - Address tuning options

#5 - Double check clearances for the relocated A/C compressor for those with A/C.

As you can see, pretty minor issues to resolve.

I have 4 rotrex'd spyders on the road for the past 1.5 years with no issues, complaints, or problems. Not to mention the fact that I have 1st hand experience with pretty much every FI option you can think of on the zz motors.

I would love to find a Houston based Lotus that needed a Rotrex. I know what 300 RWHP feels like in my car. I know how controllable and smooth the power delivery is and how I can maintain traction with my 215's and LSD on the rear. Having the same setup in an even lighter car would be simply incredible!

I can routinely make 225 - 250 RWHP on a 1zz and 300 - 325 RWHP on a stock 2zz!
Thanks for quick reply!

Re #1 and #2: so these two components are in the MR2 kit you developed? Because NA Elises/Exiges (E/E)do not have an IC, not exactly sure what a front mount Heat exchanger exactly is so I don’t know it that’s present in E/E .

Re #4: tuning has turned to be quite hard on the Lotus ECU, I wouldn’t underestimate this. I think there’s only one ECU-guru in Lotusland: CharlieX who has tunes for pretty much each (SC or NA) setup or is capable of making it.

Re #5: 99% of the NA Elises/Exiges have an AC, maybe more.

So you think, because the MR2 is also a small car, this SC + components will fit in an Elise?
Last questions: besided the graph in the MR2 forum, do you have a regular dyno plot (dynojet or whatever) showing HP and torque. EDIT: the graph is showing HP and torque, didn't recognize it as such because I was expecting the usual flat torque curve.

Thanks for all your efforts&dedication to innovation!

BTW I live in NYC, not what you call close to Houston but there are some LT-ers in Houston or neighboorhood. Maybe they are willing to let you take a look at their car so you can take rough measurements to see if everything wil fit&work.
 

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I have the 2zz Spyder that Bill installed a Rotrex on a year and a half ago. Here is a link to the build. The dyno is post #589. The first half of the thread is his build on 1zz engines. There is a lot of wasted posts in the thread as he was building it. I have had no problems with the Rotrex, tune, or engine for a year and a half, around 10K-12 K miles. As stated the dyno is post #589.

Another 1st! - Rotrex SC - Pics on 8 - #'s on 17 - Forums Index

Dyno was a Dynojet IIRC.
 

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Discussion Starter #10
Yes, the Rotrex will fit in the Elise with the mounting brackets I made for the 1zz/2zz in the Spyder. The plumbing is nice and compact as is the SC itself.

I have eyeballed the Lotus that LR has in his garage and there is more than enough clearance. The only thing that looked to be an issue was my current A/C mount. I may have to modify it to work on the Elise. However, this is a trivial task.

Like you said, the Lotus ECU is the hardest nut to crack. Tuning itself, not an issue. It is a fairly small club of us with the same level of intimacy that I have with the zz series. More so on the 1zz side but they are more similar than not. In fact, if anything, the 2zz is easier to tune than a finicky, knock prone, motor like the 1zz!

I do have several dyno plots. The one you see however is dead on accurate and comes from a program I use in conjunction with the PFC. It has been proven on 3 different dynos and I am very comfortable. It also reflects real world conditions, not a simulation as on some dynos.

That said, I do also have some dynojet files for anyone wanting to do a comparison or overlay.

On another note: I plan on doing a write up of my experience with multiple turbos, a TRD SC, a modified hybrid TRD SC that I upgraded with M62 rotors, and NA, versus multiple rotrex configurations. I think this might be very helpful for anyone looking to go FI but not sure of which application meets their wants and desires.

I feel uniquely qualified in this respect as I have had pretty much everything under the sun on this platform. I'm missing a couple like NOS and a twin screw but have had them in other cars and can relate the experience intelligently.

I'll say this now however. If you like the 2zz and are used to revving to make power, then you will love the Rotrex. Quite simply, it amplifies the characteristics of your motor as it sits. Drivability stays the same, as does your driving style. You just get more bang for your buck per rpm and in a completely linear fashion.

More to come soon, but I have to say, I am truly a convert. In fact, I once wrote a white paper as to why a particular car would want to go with an Eaton versus a centrifugal style blower! Granted, that was a much heavier platform where torque was king, but still, I’m singing a new tune these days!
 

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Looks good Grumpy, congrats!
Pretty different from regular Eaton SC's: the torque keeps (smoothly) increasing to 8K RPM instead of the flat line torque which is aimed for regular SC's.
 

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00 MRS - 2ZZ NA
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kverges is a turbo'd 2zz member running on the emanage ultimate piggyback ECU. If connectors from Lotus can be obtained, wiring harnesses can be made for the other piggyback ECU's and standalone ECU's, along with Boosted2.0's method to let the DBW cars run parallel to the stock ECU with a standalone ECU harness, just like how he did for the 03+ GTS DBW harness. Hell, Redliner9k down in Puerto Rico (PPE race header builder, expert 2zz tuner) made PFC harnesses for Corollas and Matrix's so they don't have to run off just the Hydra standlone ECU anymore.
 

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A couple of newbie questions related to centrifugal compressors, the traction drive and Rotrex:

So, from what I can gather, the traction drive part of the Rotrex SC gears the turbine blades to spin faster than the belt is turning the pully. Is that correct? Is the ration fixed or variable? Also, the lubricant is a key part of making this work and is also needed for cooling, and requires a reservoir and heat exchanger of it's own... is that what the "side reservoir" in your pics is?

Also, is it true that the Rotrex (as apparently with other centrifugal SC's) is generally more heat efficient than a roots SC because less compressed air is re-cycled? If that is true, then wouldn't it be feasible to use one of the smaller units without a charge cooler and, with a proper tune (not too lean) to acheive even a higher level of HP/Torque as, say, the Katana without detonation and heat soak issues?

Finally, to what do you attribute the rising torque curve, as compared to a flat curve for the roots SC's? Is it the dynamic range of the turbine speed... i.e., the gearing factor provided by the traction drive?

Thanks in advance for any input!
 

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Per moremonkey.com • View topic - Komo-Tec user LordZ, living in Houston as Web 3.0, showed interest in the kit. Hopefully this will result in an actual install & good result. That should be very interesting.
 

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Discussion Starter #17 (Edited)
All pm's answered, whew it has been a long day! LordZ, the dyno I posted in my thread was from this weekend! I can easily plot the A/F and will do so when I get a chance. It is even easier to describe :) It goes from closed loop of 14.7 - 13'ish - a steady 12.5. My current tune richens up a bit from 5,500 rpm up but I'll have that corrected soon. Depending on how close to the edge the tune is determines whether or not I will richen her up to 11.9 or so at redline or bleed off a little boost via cam overlap.

In kit form, you are probably looking at a mirror of grumpy's tune. He makes pretty much 325 RWHP in cooler air! It is a riot.

Free rides coming soon in the Houston area. I plan on dropping a pulley size to 85mm for even more low end. The cool thing about this setup is just how easy it is to accommodate varying driving styles and applications.

More to come as I continue to explore the realm of possibilities!
 

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Discussion Starter #20
Sorry, must have gotten confused reading those 30+ and 20+ page posts over the past two years. A new post with all the current info would be alot more helpful. :)
No problem. I've said this in private to a few people but I might as well say it here as well. I do plan on compiling the information from several long threads into one and/or white paper. I'll have to put some time into this over the weekend and update my site as well with pictures, dynos, etc.

I have extensive and intimate time with the zz series motor in the spyder having tried dozens of exhaust, cam, and FI options with and without WI. There is a lot to put together but I can handle it.

As far as tuning goes, I personally would like to see a PFC / Lotus ECU marriage that allows OBD-II. LR is working on that now so it is doable although it is by no means cheap. Don't need OBD-II then a nice stand alone is my preference.

Piggy backs are not my first choice, especially with a turbo setup. Typically their discounted price is simply not a fair trade-off for constant CEL's and intermittent driveability issues. However, the way a Rotrex comes on it should in theory be the easiest to tune

On another note, I was driving this morning and a thought occurred to me once again. The really cool thing about a Rotrex is how it mimics an NA 2zz X2. It makes roughly more torque than a red-lined stock 2zz at 3,500 rpm and keeps climbing from there :)

The cool thing about this versus a flat torque curve is the constant feel of acceleration. It PULLS increasingly harder all the way to red-line! It is truly a cool feeling!

I also tune out any jump at cam changeover; it is seamless. All you notice is a change in the exhaust note.

Oh well, enough for now, I'll save it for an all in one write up! I also have a few interested parties which is great news. I would love to be able to offer this in kit form.
 
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