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Discussion Starter · #1 · (Edited)
Hey Guys,

after being approached by HPD (Honda Performance Development) at SEMA to assist them with their new CR-Z Racers, we are now also looking into and gauging interest in our Eco-Friendly (that is what the CR-Z is all about isn't it) transmission modifications for the general consumer.

More Torque
From the brief research that I've done, it seems a lot of people aren't too happy with the power that the CR-Z is putting down. Throughout all my years in this industry, usually the first thing that comes to mind when wanting to increase power is to modify the engine; the easiest way, of course, is to go Forced Induction, but not everyone wants to go that route, especially on a brand new car. Then there's the Naturally Aspirated modifications, however, the $:hp ratio is not very attractive at all.

So what other options do we have? Well, performance is all about efficiency, and making use of the power that you have available. Besides engine modifications, there is another modification available, one that makes use of the "Torque Multiplication" principle; that modification is done within your transmission and will not affect your vehicles warranty unlike an engine modification would.

The CR-Z 6spd is currently geared to go 131mph in 5th gear, and a staggering 162mph in 6th gear. Not only is this ridiculous for a street car, the CR-Z doesn't even have enough power to reach these speeds. So what if you could harness the power of "Torque Multiplication", making your new CR-Z both faster and more efficient:

Stock Gearing (Based on 24.44" tire diameter @ 6300rpm. 128lbft):
3rd - 1.303 - 86mph (Shift Point 4417rpm)
4th - 1.054 - 106mph (5122rpm)
5th - 0.854 - 131mph (5115rpm)
6th - 0.689 - 162mph (5100rpm)
Cruising - 70mph @ 2650rpm

Proposed Gearing (24.44" @ 6300rpm. 128lbft):
3rd - 1.450 - 77mph (Shift Point 4916rpm). 11% increase in torque at the wheels, throughout the whole rev range. Equivalent to 142lbft with Stock Gearing
4th - 1.190 - 94mph (5177rpm). 13% increase in torque. 145lbft
5th - 1.000 - 111mph (5311rpm). 17% increase in torque. 150lbft
6th - 0.850 - 131mph (5331rpm). 23% increase in torque. 157lbft
Cruising - 70mph @ 3300rpm

The ratios are not set in stone. They can and will be revised dependant on market demand.

More Traction
Something the stock CR-Z is missing is a limited slip differential. Although you may only be pushing 122hp/128lbft (for the moment!), push your car to its limits and you will start to feel the need for more traction. At present, Plate Type LSD's are available, however, these are more suited for track-only cars (circuit racing) and require constant adjustments and fine-tuning to get the most out of them. For the daily driver, we propose and highly recommend a Helical LSD as they are lower cost, stronger and maintenance free.

Common Questions
Does this increase my power? - Yes & No. Your engine power will remain the same, however, actual torque produced at the wheels will increase. Your transmissions sole purpose is to take the power produced at the flywheel, multiply it and then transfer that to the ground. Without this torque multiplication, your car would simply not move (1st gear actually puts down 1653lbft, not 128lbft)

Will this affect my mpg? - Yes & No. A common misconception is that high rpm = low mileage. We have proven this to be wrong time and time again, as engine rpm is only one of several variables that contribute to your mpg. Engine load plays a bigger role, especially on a daily driver that sees a lot of stop and go action. For the average driver, not only will you experience vastly increased acceleration, your mpg will remain similar as to what it is just now. The only exceptions to this is if you do a lot of freeway driving, or if you enjoy your new found acceleration so much that you can't keep your right foot off the pedal!

How much would this cost? - On a bang-per-buck scale, this is one of the most cost-effective modifications that you could do, and one that you can actually feel and not just hear (giving the illusion you are going faster) like your general bolt-on modifications. Although I can't post definite pricing due to not being a Vendor yet, it would be within range of the current MFactory Honda FIT products along with a deal on installation (if required). We build transmissions for Honda and various other high-profile race teams; rest assured knowing your Honda transmission is in the best of hands in the industry.

Any questions, please feel free to post. Feedback/Suggestions is highly appreciated.

Thanks!
 

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Discussion Starter · #3 ·
To be honest, we're still waiting to receive the new transmission so that we can crack it open and measure the internals, as we only decided to work on the CR-Z after HPD approached us.

Due to the low rpm limit though, it makes more sense to go the close ratio gears route rather than the final drive route and would only be a couple hundred dollars more.
 

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just so everyone knows MFactory is the ****. industry champions and pioneers in sport compact racing. we purchase all of our products through james kempf at speedfactory. i know you guys are pretty close business-wise.

and i knew you guys had a contract with R & D stateside but never knew you were interested in a market so small such as the L-series tranny lol.

utah is pretty far but if you need a test mule for anything i have a spare cr-z laying around ;)
 

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Discussion Starter · #7 ·
Yeah, we work closely with Speed Factory, they are good guys.

We have clients in Japan and throughout Asia who would also benefit from the close ratio gears, hence why we have taken a serious interest in the CR-Z (besides working with HPD in the US) :)
 

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I'm definitely interested in an LSD, especially if it keeps the warranty.

I'm curious, though. I have a CVT. Are you guys going to work on the control box for the CVT or would it require a tranny swap? If a tranny swap's in order, I can't justify.

Will the LSD be compatible w/ the CVT? Can you PM me a ballpark figure on a 6mt swap w/ LSD? Thanks. Also, a sequential box (NO straight cut gears!!!!) would be killer for us CVT owners.
 

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Discussion Starter · #14 ·
For pricing, I can't post up due to not being a vendor yet, but if you visit our website, the pricing will be similar to our current Honda Fit range :)

Shatner: I've yet to look at the 6spd box, never mind the CVT! lol. I'll keep you updated though.
 

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"...that modification is done within your transmission and will not affect your vehicles warranty unlike an engine modification would."

How sure are we of this? I imagine, at minimum, modifying gearing would affect the warranty on the transmission. Are you folks offering your own warranty in lieu of the factory warranty?

I realize Magnuson-Moss would put the burden of proof on the dealer/manufacturer when denying claims on seemingly unrelated parts, but I could see a case being made fairly easily that the increased cruising rpm etc. caused by such a modification are grounds to void the entire drivetrain warranty. Jeep and Toyota have done this successfully with oversized diameter wheels/tires with regards to suspension components.

Regardless, it's awesome to see a company interested in CRZ transmission modifications so early in the game. :eek:hyeah:
 

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since the CR-Z is a hybrid... i'd be more interested in increasing mpg and not so much performance... i was thinking something like a LSD for sure and a longer FD... but if gearing would be better, then i'd go for that... something like 70mph @ 2100rpm would be perfect...

i don't own a CR-Z yet, but that's what i would go for...
 

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Discussion Starter · #17 ·
If we do the rebuild on your tranny, then everything will be spec'd and clearanced within proper operating parameters. The factory warranty doesn't really cover anything, as most items that give out inside your transmission are wear items, such as synchros, hub/slider etc which Honda would charge you for.

Besides, Honda are the last people you would want to take your tranny to for servicing; most of the technicians are clueless when it comes to rebuilding a tranny (Hence why Honda race teams have companies like us do the builds).

As for increased cruising rpm, who's to say that your daily driver on a stock CR-Z doesn't cruise at 90mph? Everyone is different, Honda can't set a specific "cruise rpm" before the warranty becomes void as that would be silly; so long as the stock 6300 rpm limit is not changed ;)
 

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Discussion Starter · #18 ·
since the CR-Z is a hybrid... i'd be more interested in increasing mpg and not so much performance... i was thinking something like a LSD for sure and a longer FD... but if gearing would be better, then i'd go for that... something like 70mph @ 2100rpm would be perfect...

i don't own a CR-Z yet, but that's what i would go for...
Trust me, you wouldn't want anything longer than it currently is, as that would only just increase the load on your engine (longer gears = increased engine load). If it's a daily driver and you do a lot of stop & go, you would actually get worse mpg.

Need to stop thinking in terms of "rpm", and think more in terms of efficiency. Honda, when they design their ratios, need to compromise between efficiency/performance. They can't make the car too fast (not because of mpg, but because it leaves them room to offer a "sportier" model), yet they can't make it too slow, all the while still needing to conserve mpg. Our gears not only make the car faster, it also makes it the most efficient it can be. Sure, you may suffer some mpg loss if you do a lot of freeway driving, but for the majority of daily drivers, they will benefit from this :)
 

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The idea of longer gears and increased MPG is a bit of a double edged sword.

Think of it in terms of bicycle gears. When riding up a long incline, you want to have SHORT gears. The ones where it makes you look a little silly, pedaling like crazy and your bike is barely moving.

If you used the tall gears, the ones which allow you to accelerate while going downhill or even increase your speed on flat roads - you will likely come to a grinding halt or be exhausted very quickly when going up the same incline.

This is what tall gears will do to the CR-Z and any other small displacement car. It will cause a lot of load which will make you downshift (go into the shorter gear/pedaling like crazy) before you can continue accelerating - OR at the very least cause you to use more throttle to MAINTAIN the same speed, thus causing LESS efficiency.

Of course with every rule, there is an exception. If one were to lighten the CR-Z by a few hundred pounds or so, then it is possible that tall gears could help achieve more MPG...BUT at the same time, if that were the case, then shorter gears could also do the same on a lighter CR-Z too!

This has been proven many many years ago and one such recent example was when we installed an Si transmission (92-95 Civic) into a VX hatch. These supposedly sporty ratios actually allowed the car to accelerate briskly but ALSO attain higher MPG. Why? Because the torqueless motor was able to more EFFICIENTLY operate in its intended range.
 
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