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The "J" Swap

bzyrice said:
It is loud when you let off the gas! But it sounds great!!
Click to expand...

It is loud right now because I am running a temporary K&N cone filter and the engine wiring harness grommet is not in, so there is a 2"x4" hole from the passenger compartment straight into the engine compartment. I will make new videos as I go along. There is a fairly pronounced change in the engine note when it switches into VTEC at about 5000 RPM.
 
I've been a member here for several years now and long-time lurker. This is the first time I've been compelled to make a post (other than a wtb nsx!) - this is such an awesome build log and tremendously valuable project for the entire community. I think we will see a pretty significant paradigm shift once this build has been ironed out and (fingers crossed) a parts kit is made available. The local pull-apart slings these motors all day for sub-$500 which would bring a whole new meaning to the 'poor man's supercar'. I'll be following the progress here closely and keenly watching for a parts kit.

Thanks again for your great work.
 
I'm usually not a fan of going away from the factory concepts on cars like the NSX, but in this case you're really just updating to what the C series turned into after it finished it's life. There's really very little compromise..... I mean the costs are cheaper so that's a bonus, the power is better so no headaches there and realistically with $ 150 for valve springs and retainers the top end RPM (if you really want it) can be just as high...........it's lighter, so even if it made exactly the same power you'd get a nice performance boost just from the weight loss.....

So all in all, I can't really see a downside to the swap if you're not worried about resale value from a market that might see it as a bad thing, but if you plan to keep it and enjoy it for yourself I can't see a downside..............
 
I don't see a downside to the swap either, and since I designed it to be completely reversible, I don't see it as being much different than many of the other builds where tons of mods are put on a car then taken off and put back to stock to sell the car. I have not done anything on my car that is not 100% reversible.

Other than the RPM limit right now, I see this swap as a win-win with a huge upside potential. Speaking of the RPM limit, do you have more information about the valve springs and where to get them?
 
Velocitized said:
I don't see a downside to the swap either, and since I designed it to be completely reversible, I don't see it as being much different than many of the other builds where tons of mods are put on a car then taken off and put back to stock to sell the car. I have not done anything on my car that is not 100% reversible.

Other than the RPM limit right now, I see this swap as a win-win with a huge upside potential. Speaking of the RPM limit, do you have more information about the valve springs and where to get them?
Click to expand...

KMS and Supertech both make performance springs/retainers for the J. I cant imagine driving an NSX with torque. My car is pushing 600hp weighs 2650 lbs and still feels sluggish up until boost hits. I should be able to get the nsx around 2500 lbs with the j-swap and a few other mods, full interior, ac , sound system. Cant wait.

http://www.ebay.com/itm/V6-Acura-Sp...Parts_Accessories&hash=item51b969f554&vxp=mtr

http://www.ebay.com/itm/Supertech-V...Parts_Accessories&hash=item3cb374b281&vxp=mtr
 
Yeah Supertech seems to be the most common upgrade for the factory springs. There are people running 700HP at the wheels with those springs and revving to 8000rpm so they will probably be enough for most people. The guys at Power Rev Racing have their own custom springs also so you could talk to them too...... I don't think the Power Rev Racing guys are charging as much as those 2 auctions, but can't remember for sure. http://www.powerrevracing.com/
 
You sir are a hero and doing gods work. Hell, Ill even use an emoji :very_drunk:

Im really interested in your plans for a kit. For us track guys this is great, pull out the c30/c32 and tuck it away safely until you retire the car from track duty and put it back to factory. Im saying this as a guy on his second rebuild. Great alternative.
 
I want to see a full kit. Mounts/fuel lines/ AC lines/wiring... you're an inspiration, sir.
 
Can't wait to see more videos and progress. I'd still prefer the C series original, but you cannot deny the economics and advancement in technology.
 
I cant wait to do this. Im gonna have the thread of the year for what Im gonna do.

but I love that your doing this.

keep up the good work
 
As mentioned before, this is what the basic motor mount swap kit would look like. This kit is not for sale on this thread, I will let you know when and where I list it for sale. If you think you need this soon, you can PM me.

IMG_20140706_150230_361_zpsc19321b0.jpg


The other swap parts that I am thinking about making available would be
1.) wiring conversion harness
2.) exhaust adapters
3.) A/C lines
4.) and maybe fuel rails.

To update the build process, I installed a Dakota Digital SGI-5 and that allowed me to tap into the tachometer signal from the J32A2 and convert it to a digital square wave signal for the main shaft and counter shaft speed sensor inputs on the J32A2 PCM and get past the 5000 RPM rev limit and enable VTEC.

20140915_145119_zpsbae0f774.jpg



I can’t wait to see what people do with these builds; it is going to be a whole new world.


I have really enjoyed driving my car again.
 
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Yesterday I had the good fortune to drive this J powered NSX and I continue to be impressed with this build.

The drive started on some fairly twisty roads and I was on the brakes more than the trottle. Once the road straighten out I was able to get a better feel for what this motor could do.

The first thing I noticed was how much torque this motor provides at any RPM. The car accelerates nicely and I found myself shifting sooner than I normally would (not because of the 7200 redline) but because power was there.

The few times I wound it up to 6000 I had to back off due to the car ahead of me. Even at that point the motor felt like it had more to give (and I'll make sure to explore that next time (that's a hint, David)).

The only criticism I have is how the car idles. Initially it idled around 800; it then it jumped up and oscillated between 1100 and 1500. I'm sure this a problem that you will be able to sort out.

I am so glad to see the project up and running; the amount of work, engineering, creativity and perserverence is astounding.

This calls for a round of applause,


:applause::applause::applause::applause::applause::applause:
 
Matt Knight said:
Yesterday I had the good fortune to drive this J powered NSX and I continue to be impressed with this build.

The drive started on some fairly twisty roads and I was on the brakes more than the throttle. Once the road straighten out I was able to get a better feel for what this motor could do.

The first thing I noticed was how much torque this motor provides at any RPM. The car accelerates nicely and I found myself shifting sooner than I normally would (not because of the 7200 redline) but because power was there.

The few times I wound it up to 6000 I had to back off due to the car ahead of me. Even at that point the motor felt like it had more to give (and I'll make sure to explore that next time (that's a hint, David)).

The only criticism I have is how the car idles. Initially it idled around 800; it then it jumped up and oscillated between 1100 and 1500. I'm sure this a problem that you will be able to sort out.

I am so glad to see the project up and running; the amount of work, engineering, creativity and perseverance is astounding.

This calls for a round of applause,


:applause::applause::applause::applause::applause::applause:
Click to expand...


Thanks Matt,

It was a really good comparison driving the C30 NSXs back to back with the J32A2 NSX. It had been so long since I had driven my NSX with the stock motor, I couldn't remember the power band. I remember that I had to rev my C30 up and that the main power band was 5-8000 rpm, but I forgot how little torque there was below 4000 rpm.

While the J32A2 is not a torque monster, you can definitely feel the torque difference between the C30 and J32. The J32 power band is more like 3-7000 rpm, so like Matt said, you just get used to shifting sooner, and you can because the power/torque is there. And something I can't seem to hear in the videos, is the pronounced shift to VTEC in the J32A2 at about 5000 rpm.

Oh yeah, I will get the idle sorted out. IACVs are a known issue on the J-series motors.



I don't know how I missed this:
Honda HR35TT Twin-Turbo V6 engine
http://hondanews.com/photos/honda-hr35tt-twin-turbo-v6-engine

Honda_HR35TT_Twin_Turbo_V6_engine.jpg
 
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I got my car up on the dyno yesterday and the results were close to what a stock 2003 TL-Type S motor (J32A2) would put down. Keep in mind this motor has over a 100K miles and I am still running my mock-up exhaust adapters with something like 1.6” internal pipes.

NSX-J32A2BaseDyno_zps8b2767ef.jpg


Here is the video.


Next I will have the exhaust adapters re-built with larger tubing and try to get a better flow design for the rear bank.
 
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adrenaline_nsx said:
on top of that its on heartbreaker Mustang dyno. Is vtec working properly?
Click to expand...

Yeah, I know the dyno may be reporting low, but as long as I keep using the same dyno I should be able to track my changes, which is really all I am concerned about. VTEC started working as soon as I got the Dakota Digital box, and it has a very audible engagement about 5000 rpm when you are driving the car and accelerating through the power band under full throttle. I wish I could capture it on video.
 
I really like your thread, Ive been following since the beginning but I was wondering if you are considering in doing some work on the engine. I started a separate thread about the J32A on a different trying to gather some information in what can it be done to the engine to increase power. I found some J guys working on their J32a and they increase the displacement up to 3.6/3.7L swapping all OEM parts from newer J series engines. Since you are keeping your NSX ecu how do you think the ecu will handle any additional mods you do the engine?? For example if I wanna do a swap like yours using a J32a block, 3.7l crankshaft, lightweight pistons, rods, TB motorworx race camshafts, valvtrain work, bigger injectors and P&P heads will the ECU work properly with all that or an EMS will be required?? keep the good work.

Nico
 
The factory NSX ECU is junk relative to newer ECU's. With a good tune on a modern ECU you will pickup quite a bit of torque and more power for sure.

With all / any of the changes you're talking about you will need a new ECU and tune. Technically I'm sure it would start and idle with the stock ECU, but it won't be even close to doing justice to the mods you've made.

The factory VTEC points on most Honda's isn't set to the optimal positions for power, it's set for emissions results. If the VTEC is set properly you should barely feel it cutover.... if you feel a large kick when it comes in that means it's changed over waayyyyy too late. My old EP3 Civic with a K20a had a factory VTEC of 6250rpm, with a proper tune that dropped to 4200rpm so that meant a massive increase in torque for that 2000rpm that wasn't there before and it makes the car feel totally different and certainly better.
 

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