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Discussion Starter · #1,001 · (Edited)
In a couple weeks, the existing transmission will be for sale once the new one's in. As a recap:

Straight-cut dog-engagement 1-4 PPG gear set:
1 - 2.615
2 - 1.611
3 - 1.15
4 - 0.909

5th and 6th are OEM
5 - 0.825
6 - 0.659

Final drive is stock Honda 4.389

WaveTrac LSD.

Works perfectly and I'll post a video showing as much. Because traffic here as dropped off so much, it'll likely also be put on Ebay. As for "how much", parts and labor were around $7000 so - given that it only has about 5000 miles on it - it'll be around $4000.
 

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Discussion Starter · #1,002 · (Edited)
As mentioned elsewhere, when WaveTrac opened up the transmission to fix their differential, they noted "several gear teeth" stuck to the magnet. Uh oh.



Turns out (thanks to malkolm666 and drtye) that the pieces were actually from a synchro hub, not the gears, so the transmission will be gone through to correct that and ensure it's good to go.

In related news, the new transmission's in the car and during a short test drive, all seems well. The very low ratio of first gear is quite apparent and will take a little relearning when leaving a stop, but is perfectly usable. I agree with JayDee; for really lightweight cars, it's great, but for a street or drag car, it would be terrible. First gear is now good to 60 mph :) going to have to test that...

In the short drive, the OS Giken LSD was completely silent - not sure what I expected, but a few owners had complained about noises - time will tell. That's mentioned mostly for a point of interest, since I always wear earplugs it doesn't really matter.

What is annoying is the vibration imparted into the chassis from my reworked rear engine mount. I think it'll have to be redone (again), this time with something that only restricts engine movement under acceleration, not steady-state driving, in order to better isolate the vibrations.
 

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Discussion Starter · #1,005 ·
Yes. It could have been made smaller but at the time it was unclear how much it would compress. Having more surface area made it easier to "tune" the mount for stiffness versus vibration isolation.
 

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Arouse the DAMPFHAMMER!
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Yes. It could have been made smaller but at the time it was unclear how much it would compress. Having more surface area made it easier to "tune" the mount for stiffness versus vibration isolation.
The video can't tell anything about the feeling under acceleration, but it looks like it works pretty well...not to soft. Awesome you could solve it :up:. Thanks for the video!

Mine engine is stiff torque damped. Stiff means damping under the E-Modul of steel, so that the engine moves zero around the crankshaft axis. It makes the oversteer allure more aggressive, which fit my drivestyle better. I like it...but the NA torque is much less and not of that mountainous character as your engines :D.
 

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Discussion Starter · #1,007 ·
Since that video was made I replaced the bottom inch (2.54 cm to you) of rubber pads with stiffer durometer material. It's just about where I want it now.
 

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Since that video was made I replaced the bottom inch (2.54 cm to you) of rubber pads with stiffer durometer material. It's just about where I want it now.
Did you any research first concerning the durability, chemical resistance and so on of them?

Thanks for transfer hint to the imperial units, after 4 years of K20a.org I am comfortable with them, except with the Btu (IT) inch/second/square foot/°F for heat conductance, which is challenging. I like more the SI version of it W/(m * K)...good we rarely talk here about heat conductance issues...LOL :D
 

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Discussion Starter · #1,009 ·
Since Urethane is used in many engine mounts already, I'm thinking it'll be fine, but it hasn't been the first time I've been wrong though!
 

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Discussion Starter · #1,010 · (Edited)
5/14 Update:

- I'm using a GM CS130D alternator and the voltage has always decreased as the car warms up. Starts out at around 14.5V but ends up at around 13.5V. The wiring was improved and now it stays above 14V.

- Had an oil system failure, common enough that it even has a name, "double-stacked O-ring." Seems the assembler at the factory making the heat exchanger reached into the bag of O-rings and didn't notice that two were stuck together. The crazy thing is that it worked great for 5 years before failing. The only reason my engine isn't toast is due to the 9+ quart capacity of the dry sump system, as only about 2 quarts of oil remained by the time I got home.



- The stainless flex bellows on the turbo downpipe cracked, so it was an excuse to upgrade the exhaust by adding a muffler to knock down some of the noise, both for my benefit and to attract less attention. The Borla muffler works really well. The lower section can be removed for track events.





- Lastly, the transmission sold; the new owner out in Arizona plans to install it in his drag car.

- In the works: Diffuser and wings.
 

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...The Borla muffler works really well...
This is an interesting feedback kb58. What model is it?

I did some research on mufflers few month ago to decide for one. Borla's ProX...-Technology would have been my first choose but the design didn't fit the tiny clearance volume of the Lotus under the trunk section. They have a decent pressure drop to sound calming ratio, if one search for a certain ratio of the upper ear-noise-acceptance area. Finally designed was ruled by clearance, so I went to Vibrant Performance, they have a not too bad 1 in 2 out-muffler, giving more freedom to do the piping in a thermodynamic sense-making way.
 

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...an oil system failure, common enough that it even has a name, "double-stacked O-ring."
This is a very good fitting phrase, kb58. K-Tuned delivers their water-pump-delete-kit water inlet port optional with such an O-ring-construction, which get squeezed in such way every engineer must cray. The O-ring nut width is smaller than the O-ring diameter and less deep then about 2/3 of the diameter. I don't know what kind of construction book or rule they use, but this makes no sense to me. O-ring sealing systems are well described e.g. by the supplier data. To squeeze those until they brake isn't integrated in non of these manuals.
 

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Discussion Starter · #1,013 · (Edited)
This is an interesting feedback kb58. What model is it?

I did some research on mufflers few month ago to decide for one. Borla's ProX...-Technology would have been my first choose but the design didn't fit the tiny clearance volume of the Lotus under the trunk section. They have a decent pressure drop to sound calming ratio, if one search for a certain ratio of the upper ear-noise-acceptance area. Finally designed was ruled by clearance, so I went to Vibrant Performance, they have a not too bad 1 in 2 out-muffler, giving more freedom to do the piping in a thermodynamic sense-making way.
The Borla muffler I used was 40359.

Forgot to add that it works so well that I can hear other noises... including what sounds like engine knock under high boost... I'm going to set up a log file to record the knock sensor output to see if it's real or imagined. If it's real, it's probably due to the back pressure from the muffler, so for the street at least, boost will have to be dialed back. Another experiment would be to add a tankful of E85 and see if it vanishes.
 

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Discussion Starter · #1,014 · (Edited)
Diffuser added. Still have to fill the gap above it, probably with screen. Next up is either the wings or cold air intake - both have to be done. The rear wing will be a duel-element directly above the outlet of the diffuser, and high enough that it's in clean air. No, the front and aft wings will only be mounted for track events. The diffuser was about as far as I was willing toward the boy-racer look.





 

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Discussion Starter · #1,015 · (Edited)
With the diffuser done, it means something else has to pop up. Right on schedule, not one but two nut/studs mounting the turbo were found backed out of the exhaust manifold... nice. New locking studs and nuts are on order, but it's a serious pain to get at the lower inside nut. The compressor housing has to be removed just to gain access to swing a wrench, the consequence of a 1.03 AR turbine housing making things tight.
 

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Discussion Starter · #1,016 · (Edited)
In researching studs, I quickly found out that Inconel is the right stuff. From my website blog:

Regarding the turbo studs, after doing some more reading and getting some helpful hints on the Midlana Builders’ Forum, it was decided that they’re being replaced again, with the only type of stud that won’t stretch under high heat – Inconel. Actually ordering them though was a bit of a drama. For whatever reason, they’re fairly common in the aftermarket – in Australia – but not so much here. Testing the waters, I found they wanted about $50 shipping for their $50 parts, so no go there. In short, they were found domestically in a somewhat-surprising-but-shouldn’t-have-been source, Mazda. Seems the factory had such serious problems keeping their turbos attached to the second(?) gen RX-7, that they use Inconel studs. Thanks somewhat to mass production, they’re “only” $12 each, but hopefully once they’re in, that’ll be the end of that.

As an aside, a vendor in the US advertises “Inconel” studs, but reading the fine print, it turns out they’re actually “Incoloy”, which research shows isn’t the same thing. The vendor tried convincing me they were and that Inconel is just a brand name of Incoloy, yet research seems to indicate that Inconel has more nickel in it and is quite a bit more expensive (less profit). We use Inconel at work for really high temperature applications, not Incoloy, so that sealed the deal.

Lastly, if someone tries selling you fasteners and claims they’re Inconel, a simple test is that they will look like ordinary steel (not stainless) parts, and are non-magnetic.
 

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In researching studs, I quickly found out that Inconel is the right stuff. From my website blog:
Inconel is also the material some OEM's use for the turbine of their turbos, like Porsche 911 Turbo. It is also used for the Thermocouple Typ K as material to shelter the two welded sensor wires with the two different materials to cause the Seebeck effect. Yes it is a brand name for a Nickel alloy and it is pretty standard here for exhaust parts when it comes to really high temperatures (beyond 900 °C).
 

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But of course - using the following references
Very nice quotes! I use followings:

Both where quite helpfully in general to learn the concepts in the aerodynamics of an car but for modeling this things in a 1D or 0D-manner it was more helpfully to have studied flow dynamics.

Concerning idle tuning with AEM Infinity kb58 I have something you might be interested in https://drive.google.com/file/d/1LI7uLA4KKAb2QTo7hO-F1gbLWN1MFhi8/view
 
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