The "J" Swap

I am familiar with the J36, however I don't think I will go past the 93mm stroke of the J35, but who knows. I can tell you, that as soon as this is running, I will probably pick up a J35A3 from an 01-02 Acura MDX

Make sure you get 03+ j35 which comes with 260hp vs 02- 01 only 240hp. They cost the same too. Just FYI.
 
Winx909 said:
I am familiar with the J36, however I don't think I will go past the 93mm stroke of the J35, but who knows. I can tell you, that as soon as this is running, I will probably pick up a J35A3 from an 01-02 Acura MDX

Make sure you get 03+ j35 which comes with 260hp vs 02- 01 only 240hp. They cost the same too. Just FYI.
Click to expand...

I will stay with the 01-02 J35A3 to avoid the DBW J35. The J35A3 is all but identical to my J32A2 except for the longer stroke and intake manifold spacer, which I would have to take out for engine hatch clearance. I would probably upgrade to the 09 TL SH-AWD intake manifold, or look at running dual throttle bodies on the J32A2/J35A3 intake manifold.
 
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bzyrice said:
Hi velocitized.. Can I ask how u make up your mockup pieces?
Click to expand...

Sure, the mockups are made out of expanded PVC board. The board is basically PVC foam, so it glues together with normal PVC pipe glue. It is very light weight and rigid. I buy scrap pieces for $10 a pound and since it is so light weight it doesn't cost much at all. I usually pick up some 1/2" and 1/4" material, then to build a mockup, I cut out the rough shape several times and glue, stack and clamp for about 30 min, then start cutting and shaping. It is very easy to cut with any woodworking tool.
 
The J32A2 is a great engine! I had one swapped into a 2001 Accord years ago, plenty of torque and an easy engine to source. Great thread Velocitized!
 
The engine is about to go back in, but before that I decided to install the SOS clutch dampener delete kit and it looks like it was a good thing I did. The clutch fluid in the reservoir looked clean, but this is what came out from the slave cylinder. I have a “one man” vacuum brake bleeder and I highly recommend one of these if you ever bleed your own brakes or hydraulic clutch. I bled the clutch line until clear fluid was running through. Just keep an eye on the reservoir, because you don’t want that to run dry.

SOS Clutch Dampener Delete
IMG_20140616_104935_776_zps310031b9.jpg


Old clutch fluid, nasty!
IMG_20140615_162536_205_zps844713b8.jpg


Then I also had to make some more modifications to the front mount adapter bracket because it would not hold the torque spec. So, I clearance the block some more and now the hole goes into the bell housing, but that shouldn’t be a problem. I put a steel insert in the front mount and then put a nut with some Loctite on the back and torqued the nut to 20 lb. ft. Now the front mount can hold the full 43 lb. ft. of torque specified for the NSX front mount. The adapter bracket is torqued to the J-series block at the torque specified for the J-series front mount of 28 lb. ft.

Block clearance for front mount
IMG_20140611_102345_401_zps9739045c.jpg


Modified front mount adapter bracket
IMG_20140611_102851_308_zpsa9dc0134.jpg


I did run into one possible stumbling block for the wiring. Turns out, the NSX traction control motor is a six wire stepper motor and the J32A2 traction control throttle body is a normal two wire DC motor. So, it may take a little more work to get the traction control working again, but I am not going to let that stand in my way.
 
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Velocitized said:
For perspective, the C30 is about 31” wide and the J32 is about 23” wide. From crank center to the top of the intake manifold, both engines are about 20” tall.
Click to expand...

For information sakes, what are the dimensions of the NSX engine? 31" wide x ?" tall(bottom of oil pan to top of intake) x ?" long?
 
dablackgoku1234 said:
For information sakes, what are the dimensions of the NSX engine? 31" wide x ?" tall(bottom of oil pan to top of intake) x ?" long?
Click to expand...

NSX engine = 31" wide x 27" tall x 22" long
 
rj45 said:
Awesome progress, don't ever give up!

I just saw this post. Kind of interesting. What would be the best engine for the 95? I know I'm going to need to do this swap eventually. I might as well start learning now.
http://www.hondatuningmagazine.com/tech/htup_0904_honda_j_series_engine_swap/
Click to expand...

Yeah, I saw that article when it came out in 2009, inspiring.

As far as which J motor to swap into an NSX, I would stick with the J32A2 or the J35A3 for the 91 to 94 drive-by-cable cars and probably the J32A3 or J35A5 for the 95+ drive-by-wire cars.

Here is some information about a selection of Honda J-Series engines:


Code Model Years Throttle by wire Piston Spray? HP@RPM TQ@RPM CR Redline Fuel Cut

J37A2 RL 09- Yes Yes 290 6200 256 5000 11.2:1 6800
J35A3 RL 06-08 Yes Yes 290 6200 256 5000 11.0:1 6800
J35A3 RL 05 Yes Yes 290 6200 256 5000 11.0:1 6800
J37A4 TL Type S SH-AWD 09 Yes 305 6300 273 5000 11.2:1
J35A8 TL Type S 07-08 Yes Yes 286 6200 256 5000 11.0:1 6800
J32A4 TL 07-08 Yes No 258 6200 233 5000 11.0:1 6800
J32A3 TL 06 Yes No 258 6200 233 5000 11.0:1 6800
J32A3 TL 04-05 Yes No 270 6200 238 5000 11.0:1 6800
J32A2 CL/TL Type S 03 No No 260 6100 232 3500 10.5:1 6900 7200
J32A2 CL/TL Type S 01-02 No No 260 6100 232 3500 10.5:1 6900 7200
J32A1 CL/TL 01-03 No No 225 5600 217 4700 9.8:1 6300
J37A1 MDX 07-09 Yes Yes 300 6000 275 5000 11.0:1 6500
J35A5 MDX 06 Yes No 253 5800 250 3500 10.0:1 6200 7000
J35A5 MDX 05 Yes No 265 5800 253 3500 10.0:1 6200 7000
J35A5 MDX 04 Yes No 265 5800 253 3500 10.0:1 6200 7000
J35A5 MDX 03 Yes No 260 5750 250 3500 10.0:1 6200 7000
J35A3 MDX 02 No No 240 5300 245 3000 10.0:1 6200 7000
J35A3 MDX 01 No No 240 5800 246 4400 10.0:1 6200 7000

Note:
J32 = 89mm bore x 86mm stroke, rod length 161.8, rod/stroke ratio 1.88
J35 = 89mm bore x 93mm stroke, rod length 158.5, rod/stroke ratio 1.70
J37 = 90mm bore x 96mm stroke, rod length 155.5, rod/stroke ratio 1.62

Sorry, I have this information in a spreadsheet and it doesn't paste well.
 
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A stepper motor? Huh? Isn't TCS in the NSX just some wheel speed sensors and a signal telling the ECU to cut fuel?
 
Surprising weight savings!

Just before the motor went back in, I picked up a hanging scale ($90) for my crane hoist to weigh the engines and here are the results. Both engines were weighed as complete as could be with the transmission, alternator, A/C compressor, motor mounts, adapter brackets, and throttle bodies (two for the J32A2) minus fluids.

C30A = 620.1 lb.
J32A2 = 558.4 lb.

61.7 lb. weight savings is less than I expected but not too shabby.

NSX C30A engine weight
IMG_20140617_172117_511_zpsa0b125d5.jpg


IMG_20140617_172129_650_zpsb5a6f4ee.jpg


J32A2 engine weight
IMG_20140615_132719_113_zpsdabc2db1.jpg


IMG_20140615_132817_405_zps460f9925.jpg
 
Once your start up vid goes on youtube, I'm sure everyone who followed this tread be will proud of your hard work and dedication to the swap. Keep up the good work.
 
Well after a lot of work and help from my son, the moment has finally arrived. Here is the initial startup video with cats but no muffler. The startup went well, I just have a few check engine codes to sort out for the missing "automatic" transmission. Should be on the road soon.

http://youtu.be/CuQiEWyh-H4

 
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I am glad to be the first to post after your startup video. Very nice work and very proud of you!,
 
Great workman!! Great to see that you followed through and completed the project.. Looking forward to your kit!!
 
Looking good. I have a 95 nsx what do you think about putting a j35a8 in it? Because If I did this I would like to turbo it and i know you can use the flashpro for full tuning. When I did the j32a2 I used the greedy blue and it worked but not everything could be changed.
 

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