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Discussion Starter #1
First and foremost A BIG thanks to Scott. Without him this would not have been possible.

Tomorrow I’ll be on my way to Jue Motors to pick up my 04 Lean Burn CVT. Scott is probably the only person in the country with the knowledge and passion to tackle this job.

A few unknowns that he was willing to undertake and overcome. To Scott’s knowledge all other lean burn conversions have been on 00-03 models, wiring for 04-06 is different. Also I ended up using a different ECU than the J-51. I used P/N 37820-PHM-309.

I was lucky to find this new P/N used in Japan. This part is available for purchase as new stock but it’s expen$ive ($1000). I managed to source mine for $200.

Refere to Scott for any technical questions. I’ll be posting MPG updates for those interested in what lean burn can do for a CVT.

I had the pleasure of driving Scott’s manual Insight while he was working on mine. I was getting 75 mpg on my work commute with his 5 speed. My CVT would get 63 mpg on the commute.

I’m hoping to get 75 mpg or better with my 04 lean burn with OBDII C&C and IMA C&C.

Updates to follow and thanks again Scott!!!
 

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Discussion Starter #2
83452





First morning commute to work. Maintaining LB is much harder than I expected. IMAC&C helps tremendously with maintaining and slipping into LB.

I spent most of the commute chasing LB rather than focusing on FCD. Hopefully I’ll be able to pull over 70 mpg with practice.

After driving Scott’s 5sp for a week a can tell than a LB CVT will never be as mpg efficient as the 5sp.

Anybody else out there with a LB CVT? I’d be interested in your insights with maintaining LB at speeds of 60-65 mph.

9B34B298-1594-461E-87E2-C0CADB191AD0.jpeg
 

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Discussion Starter #3
72.8 for today’s morning commute. I was able to easily hold LB for all the commute. Average speed was 50-55. I was able to hold LB with 4 bars of regen, FCD fluctuating between 75-100.

I got to 77 MPG but lost it the last few miles of city driving. Hit every light in town. These numbers are very similar to what I was getting with Scott’s 5sp.

An LTO upgrade with 5 times the battery capacity would put LB on steroids and probably net me close to 85-90 mpg at cruising speeds.

83474
 

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Could you monitor the engine "vacumm" and TPS values while in LB with your OBD tool and post your results on this thread?
TKS
Willie
 

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Discussion Starter #5
Willie, I haven’t dug into the OBDIIC&C. I have been busy with several projects on this car, it’s finaly complete. Next on my list to do is OBDII programming and display knowledge.

I will try my best to find those values for you.
 

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I have a JDM import CVT in UK with lean burn. I used to commute 57 miles each way and averaged about 64.8 US mpg (73.5 Uk mpg). Best door to door mpg on that journey sitting at 50mph all the way was about 82 US mpg and best motorway stretch ignoring the town sections at each end, which was around 50 miles, was about 98 US mpg.

You probably know some of these bits already but the car will only go into lean burn below 65mph. It’s quite difficult to hold the car in lean burn, especially if the road undulates and needs more than a feather of extra throttle. The CVT has a habit of running through the gearing if a bit more throttle is needed, especially at lower speeds like 50mph, which is another lean burn killer. I think the next best mod on a CVT car would be some way of locking out the gearing in top. Someone mentioned putting a resistor across the TPS on the TCM line to fool it into not downshifting the CVT by making it think the throttle was less open than it thought - that same principle would probably fool the ECU into not taking the engine out of lean burn because it wouldn’t notice your throttle input. I’m no expert though, I wouldn’t know where to start with that.
 

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I wish somebody with LB CVT would do my heated gas line modification and see how it affects transmission characteristics.
 

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Great mod! A CVT will always be at a disadvantage vs a manual, at least in the Insight. Top ratio is only a little taller than a manual's 4th gear, and the CVT has more parasitic loss than a manual (maybe 5-7%?). Still, looks like you're seeing some savings.
 

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Discussion Starter #9
Thanks for the input Jonny, I have noticed I get LB as low as 10 mph at 1200 rpm up to 67 mph. LB in low RMP city traffic is easy to hold. Holding LB above 60mph is difficult.

I have IMAC&C, with it engaged at 25% I notice LB is much easier to hold. I can even accelerate up a slight grade and hold LB with the FCD over 100mpg.

I’m hoping to upgrade to a 3.3 kw LTO and use it as a PEHV. I think a LB CVT LTO could get 100 mpg at cruising speeds of 55 mph.

Ecky, I like the headlight mods you did with the Black paint. Any chance of you posting a write up on that?
 

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Discussion Starter #10 (Edited)
My best run yet!!!
Should have got a screen shot at LB.

84317



68 deg sunny day. 44 mile stretch on CA 99 from Visalia to Fresno. Cruising 55 mph LB engaged full ride.

I have been cruising this route over the winter at 60 mph and the best I get is mid 70’s. Looks like I might slow down to 55 mph for my morning commute.

Need to get the LTO setup so I can bust 100mpg. My round trip work commute is 90 miles. I’d like to do it on less than a gallon.

Thanks again to Scott for getting this LB on the road.
 

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The CVT ratio control has been discussed quite a lot but I don't think anyone has tried what I suggested yet.
i.e. the series resistor hack..
It may or may not have any effect, and needs to be inserted into the tps line near to the TCM so that it does not affect the tps line into the ECM.
 

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Discussion Starter #12
Thanks for chiming in Peter. I would be interested in trying to get that modded to make a LTO LB CVT.

I recently ran into an old friend from my elementary school days. Lost touch with him in high school but turns out he an Electrician with 20 years experience currently working for my county.

He’s reading over Natalya’s LTO thread in order to evaluate if it’s a task he wants to undertake. I’m sure he has the knowledge to ask the correct questions here and get it done.

I have the passion but lack the knowledge to get any of this done. Too clueless to even ask questions!!! I’m hopeful between Peter, Scott, and my friend they can tweek my CVT to be modded to get 100 mpg at 60 mph cruising speed.

I hope to reach out to you soon Peter to complete my parts list to buy from you. Can’t wait for the current hack and LTO to fully appreciate what the IMAC&C is fully capable of.
 

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Some CVT Ratio Mod info & thoughts from earlier..

Some serious data gathering and reverse engineering would likely be required on the two way serial communications lines between the TCM & ECM for a start. TMA & TMB IIRC. Numerous CVT scenarios would have to be recorded, normal driving, low gear, high gear, D & S, and everything in between.

The other various sensors tps, map, speed, that also feed into the TCM would have to be monitored/recorded so we could see patterns and correlations between usage patterns and comms traffic.
Then after detailed analysis if we could see some patterns and possible avenues to attack/hack the system we would have to make and install a device to do that whilst not throwing codes.

However after a bit of looking it might be simpler than we think..

The TPS (Throttle position sensor) 0-5v signal seems to feed into the pulley ratio decision making criteria.
Generally in my CVT experience lower TPS levels = higher gear ratio and lower rpm.

So if we fool the TCM TPS input we might be in business.
Note the TCM TPS input is pulled to ground internally, probably by a 100k resistor.
I suggest add a 100k multi turn pot into the TPS line as it enters the TCM.

Note the TPS signal is shared with other computers, so you need to intercept it just as it goes into the TCM.

Fiddle with the pot and report back.
 

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Discussion Starter #14
Peter, I looked up the Potentiometer you spoke about. As I mentioned I’m clueless and most of what you speak of is a forieng language to me.

If I’m understanding you correctly this potentiometer would be tapped into the TPS line allowing the user in therory to trick the CVT into a higher gear ratio, lower RPM. Coupled with LTO assist and LB sky’s the limit for MGP.

Would this be set up with a line running to the dash where a switch similar to the CalPod could engage it? Sound like a fairly simple, low cost modification. Wouldn’t be out too much if it didn’t work and OEM configuration would be a simple revert to if it gives any problem. Is this a realistic assessment or am I wrong in this line of thought?
 

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You could put a switch across the pot to revert to oem (straight through).

Of course we have no idea if this will work it's just an educated guess, we might get a CEL/TCM code straight away.
 

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Discussion Starter #16
Same stretch of road, obviously the road conditions are favorable. Average 50-55 mpg. Sunny 68 deg,winter blend California gas.
D0774420-3EA0-44BA-A070-7F18A1E7AC04.jpeg
 

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OK... I have REALLY been a bad Insighter here and not gotten pics and info to you about the Amsoil bypass setup. I will, I promise!
BUT! I have to congratulate you on the lean burn setup! I’m always keeping my eye out for a module, and the price you got is great! Have your family keep an eye out for one for me!
Very jealous, but super excited for you!
 

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Discussion Starter #18
No worries John. I decided not to pursue the oil bypass. To many other project$. I put that money into a CVT with 60k miles on it. Kirkland synthetic 0-20 is $1.25 a quart. I’ll just stick to 7500 mile OCI’s.
 
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