My J swapped NSX...sorry for the wait. love or hate

[Rogue MotorSports]

Retrofit/Swap kit….hummm..

Parts list..

Well the J-series will bolt to the NSX trans, so pick up a J-series of your liking. I like the idea of the J35 with the Type-S cams. Interestingly, Honda uses the J35 in their Outboard V6 motors and they use the K-series in their 4 cylinder outboard motors.

Based on part # 90429-PC6-900 it looks like Honda used the same bolt pattern on the business end of the crank for all B, C, D, F, G, H and J series engines, so finding a flywheel/clutch combo that will bolt up to the J and fit inside the NSX trans should be possible, I am highly optimistic that the NSX flywheel/clutch will bolt up.

Front motor mount, Rouge has this pretty much figured out.

Passenger side motor mount, I think an adapter could be made to go from the J block mount to the stock NSX mount.

OBD2 to OBD1 adapter for older NSXs

Exhaust adapter, I could see an adapter pipe going from the J35 head to the stock NSX cats, so you could use any of the NSX exhausts.

I know this seems overly simplified, but this just may be one of the most viable swaps/retrofits around.

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Ahh, the agony of waiting.

You cannot use a j35a8 or the newer j37 engine as the block housing is different how the trans bolts to it.

To sum it up, drivers side mount will be oem nsx, rear mount will be oem nsx, front mount will be oem nsx modified a slight bit. passanger mount I am going to try to develop a bracket to incorporate the the stock oem nsx passenger mount.

You cannot use an obd1 to obd2 conversion. You will basically convert your obd1 car to obd 2 using the factory ems. That will include the ecu and dlc and all wiring. When its plugged up to a scantool it will read as a TL the year and vin off the ecu being used.

I am building my setup for the exhaust to bolt to an oem exhast setup. It is very simple and straight forward.

Always use the ECU that came with the donor engine, and in this case it is the TL's ECU and that is a OBD-II.

Then, you can get it serviced at any Acura dealership, since the Honda Diagnostic System will recognize the ECU as coming from a 2009 TL.

Depending on what you are doing with the car the best ecu to use is 07-08 tl ecu, that way you can use flashpro with it for a tuning solution. You can use a fic or emanage, but you cannot change the timing. The factory ecu will always pull the timing back out or add the timing back in as it is self learning.

A huge upgrade for auto nsx owners would be to get a modern 6 speed auto tranny. Is that possible?

Yes that is very possible. As the trans from the j32a3 will bolt straight to the block.


here is my update for the evening. I got the mounts, starter, and slave cylinder in. I will be doing more work to the car as this week progresses and will update.

 

[myhui]

I strongly prefer swapping both the engine and transmission together.

I'm so glad that Honda made a 6MT TL.

 

[Rogue MotorSports]

I personally think that's the best route to go. I am doing it with the c transmission at fitst just to keep everything very simple.

 

[dablackgoku1234]

The only "downside" I see for mating a C Tranny to a J block...is the fuel mileage...lol.

The TL 6 speed is pretty much a JDM short gear 5 speed with an additional 6th gear for highway cruising gear. 65 mph in a 6th gear TL is 2200rpm vs 2800 in a NSX 5 speed or 2600 in a NSX 6 speed.

 

[Velocitized]

You cannot use a j35a8 or the newer j37 engine as the block housing is different how the trans bolts to it.

To sum it up, drivers side mount will be oem nsx, rear mount will be oem nsx, front mount will be oem nsx modified a slight bit. passanger mount I am going to try to develop a bracket to incorporate the the stock oem nsx passenger mount.

You cannot use an obd1 to obd2 conversion. You will basically convert your obd1 car to obd 2 using the factory ems. That will include the ecu and dlc and all wiring. When its plugged up to a scantool it will read as a TL the year and vin off the ecu being used.

I am building my setup for the exhaust to bolt to an oem exhast setup. It is very simple and straight forward.



Depending on what you are doing with the car the best ecu to use is 07-08 tl ecu, that way you can use flashpro with it for a tuning solution. You can use a fic or emanage, but you cannot change the timing. The factory ecu will always pull the timing back out or add the timing back in as it is self learning.




Yes that is very possible. As the trans from the j32a3 will bolt straight to the block.


here is my update for the evening. I got the mounts, starter, and slave cylinder in. I will be doing more work to the car as this week progresses and will update.

Getting more excited!

I was thinking of using a J35a3 from an 01-02 MDX and swap in the Type-S cams from the J32 or the J35, then using the ECU from the TL again either the J32 or J35 TL not sure yet. I was looking to use the OBD2 to OBD1 conversion harness only for the plugs that go from the ECU to my chassis harness, the engine wiring would be maintained and plug into the OBD2 ECU. I just don't want to cut up my chassis wiring harness.

Front mount can be modified OEM NSX, sweet. It is getting better every day.

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Are you going to use the CATs from the J-series right off the engine or the ones on the NSX exhaust?

 

[Rogue MotorSports]

Getting more excited!

I was thinking of using a J35a3 from an 01-02 MDX and swap in the Type-S cams from the J32 or the J35, then using the ECU from the TL again either the J32 or J35 TL not sure yet. I was looking to use the OBD2 to OBD1 conversion harness only for the plugs that go from the ECU to my chassis harness, the engine wiring would be maintained and plug into the OBD2 ECU. I just don't want to cut up my chassis wiring harness.

Front mount can be modified OEM NSX, sweet. It is getting better every day.

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Are you going to use the CATs from the J-series right off the engine or the ones on the NSX exhaust?

You can't use that engine with the new dbw ecu. If you were going to go with that engine you aem makes a compatable ecu for it.

I won't be using any cats with this setup. If your in an emissions state you can use the factory precats from a tl and get rid of the third cat and it should pass emissions.

 

[Velocitized]

You can't use that engine with the new dbw ecu. If you were going to go with that engine you aem makes a compatable ecu for it.

I won't be using any cats with this setup. If your in an emissions state you can use the factory precats from a tl and get rid of the third cat and it should pass emissions.

My car is a 1991 NSX. 1991-94 NSXs were all OBD1 and DBC, so for me to keep things simple I was looking for a DBC J35a3 or J32a2. Most likely the J35a3 with either the J35 or J32 Type-S cams. I am looking for the simplest swap possible initially, if all goes well, i can look at more options down the road. To be able to swap in a J motor, test it out, see if I like it then if not I will rebuild my C30, if I like the J then look into future upgrades for more performance.

 

[myhui]

This is how other shops make their transmission adapter plates.

K-Series to S2000 Transmission Adapter Plate

 

[Honcho]

The other enticing prospect is using a J 6-speed on our C engines. NSX 6-speeds are almost $8,000 new and about $4,000 used. If we could figure out how to get a J-series trans to work, it would cut the cost way down.

 

[dablackgoku1234]

The other enticing prospect is using a J 6-speed on our C engines. NSX 6-speeds are almost $8,000 new and about $4,000 used. If we could figure out how to get a J-series trans to work, it would cut the cost way down.

This is exactly my thought. Since the J series bolts right up, there's no need for an adapter plate. It's just a matter of drive axles, mounts, and shift linkages.

 

[myhui]

Maybe I'll wait five more years and sell my pristine C32 transmission for $10k to finance this project.

 

[JD Cross]

I'm curious as to how many manual TL's would have been sold.
Would have though the vast majority of TL's would be automatics?
If the population of TL six speeds is not all that large then prices won't stay low for long.

 

[myhui]

Just order the whole engine and transmission for the 09 TL brand new from Honda.

 

[myhui]

Or swap in a sleeved and boosted K24 to get great acceleration due to lower mass.

 

[Rogue MotorSports]

Just order the whole engine and transmission for the 09 TL brand new from Honda.

The 09 is no good unless you want automatic. Or you can use the 07-08 tl manual trans but those are difficult to find at times

Or swap in a sleeved and boosted K24 to get great acceleration due to lower mass.

To me the j series is much better than the k series. The j doesn't weigh much more than the k. It has considerable more torque and I think it stays more true to the car.

 

[Honcho]

I found a 6-speed from a 05 TL on EBAY for $849. Just sayin'


The ratios compare favorably to the NSX too, though the TL is a little taller geared:


Gear TL NSX
1st - 3.93 | 3.066
2nd - 2.48 | 1.956
3rd - 1.70 | 1.428
4th - 1.25 | 1.125
5th - 0.98 | 0.914
6th - 0.77 | 0.717
Final - 3.29 | 4.062

Final ratios TL NSX
1st - 12.93 12.45
2nd - 8.16 7.95
3rd - 5.59 5.80
4th - 4.11 4.56
5th - 3.22 3.71
6th - 2.53 2.91

 

[dablackgoku1234]

 

[Rogue MotorSports]

Nice info. Is that based on the factory nsx tire size for the tl 6 spd also?

 

[dablackgoku1234]

Based on 25 inch diameter tires.

 

[Rogue MotorSports]

Very nice. I was wondering if I would have the gearing to break 200mph in the texas mile. Guess I will need to go with the tl trans or change the fd in the nsx trans.

 

[latzke]

I think the C30/32 will do 8500 rpm now if the fuel shut off would allow it.
It's an engine configuration that is designed to rev high with acceptable stresses.

I agree, noting that it seems the weakest link for C30/32 at higher-than-8000 RPMs is the oil pump gear. Hence the existence of an aftermarket billet gear (and broken oil pump gear as cause of engine failure after mis-shift-induced over-revs).

 

[myhui]

To me the j series is much better than the k series. The j doesn't weigh much more than the k. It has considerable more torque and I think it stays more true to the car.

Look at what these guys managed to get out of four cylinders with a big turbocharger: http://www.s2ki.com/s2000/topic/888176-holy-moly/

 

[e.pie]

Look at what these guys managed to get out of four cylinders with a big turbocharger: http://www.s2ki.com/s2000/topic/888176-holy-moly/

View attachment 100862

Nice peak numbers for sure, but a J will have much more power under the curve.

 

[E-Nough Logic]

Haha thats my buddy Alex's s2000. Synapse tuned my NSX too. Alex's car is making 1000+ now down at kings performance with a new build. I used to drive the other black 907whp s2000 at the track. Only drove it at ~725whp we went 9.95@145.

Are there any big power J series out there 700+whp?

 

[Rogue MotorSports]

I will try to grab a few graphs tonight. People have not been modding tge j series as heavily as there was no tuning solution. Iirc there was a srock engine j making around 500 whp and high 400 tq on a 6262. There is also a stock motor stock trans j making a little over 700whp.