NA1 J series swap

[jmillar691]

Before I go into detail, I apologize if this topic has been gone over before on these forums, I just feel that I have some more specified questions about this topic that I'm hopeful you NSX guys will be able to shed some light on.

Sitting in a container in Japan right now are 3 NA1 Honda NSX's. 2 silver in colour code, one is a '93, other is '94, third is a black '95 that has been modified much beyond my liking. The '93 is a documented, one owner, 42k all original. I can personally vouch for this exporter as I have purchased an S14 Silvia and a beat up '90 Skyline from him before. I inquired about the car and he sent me pictures and a we have reached an agreement on what I feel is a fair price. My main questions however are 1) what are the differences between a JDM NA1 NSX and a USDM? Obviously other than RHD, are there any glaring differences between them? 2) The car is automatic. It runs like a top and is in all original condition. I happen to have a j35z3 long block out of the USDM '08+ Accord with 6 speed transmission. I understand physically (size wise) the difference between the C series and J series engines (DOHC/SOHC, 90 degree block/60 degree block). Now outside of some custom fabbing that would have to be done to mount the engine, how would I possibly go about transmission? I have heard rumours that the NSX engine spins the opposite direction as opposed to every other Honda engine (pump side perspective). Is this feasable? Any insight or information from the board members here would be a huge help.

 

[Track Addict]

Don't mind me, I'm here for the roast.

 

[angus]

OK, I'm subscribed too.

 

[A.S. Motorsport]

hmm i smell a roast as well...

In response to your question though,
Yes you can it probationally won't require extreme fabrication (see the LS7 swap :biggrin the J is compete opposite (tranny and crank rotation) altough a mild J36 build will net you 340 HP for not alot of money.

Anyway it would be a rather different car after wards (low revving 6.5 redline)

Be sure to fit RL/Legend internals as those are forged instead of cast.

 

[shawn110975]

.
so you have in a shipping container 3 JDM NSX's waiting to ship to the USA?

I only have one question

" do you know a guy named 04HondaNSX "

I would be more worried about how your gonna get them thru customs

LOL

great ready... some of these guys dont wake up till 9am so let the flames begin

 

[nikey22]

Illegal to import any car less that 25 years of age from Japan (RHD), sorry bud, but you didn't do your research at all.

If you are stopped by the police, they will cease and are legally allowed to crush the car if they choose ... :smile: good luck

 

[NA1MT]

I wouLd think that the only way you could import them legally would be as parts.....but a whole car would not qualify as parts. I knew someone that claimed they had imported skylines in pieces.....front clip, rear clip, drivetrain. Truthfully why would you even want the hassle? So you could have your steering wheel on the wrong side of your car??

 

[Nukem]

Wouldn't be worth it unless it was a Type-R or Type S(or S-zero) Even then not happening for a few years unless you do it illegally. I know a guy from high school who shipped over a Silvia in pieces and put it together. Couldn't register it or get tags for it. Ended up becoming a track only car.

 

[jmillar691]

Kind of expected to get flamed for this anyways lol fine by me, I'm sure others have asked the same question before. To correct the above poster who said it has to be 25 years old, I live in Canada and it is 15 years as of date of manufacture. There are many 15-20 year old imports cruising around Ontario, and I've even just recently seen (not yet on the road) a '97 R33. This isn't my first rodeo, but my first with an NSX, so any advice on this project would be appreciated. I do understand the much different characteristics of both engines, but to anyone else who lives in Canada, parts for a C30A are few and far between (and incredibly expensive), whereas J series parts are available at nearly the corner store. It may not sound/perform up to par with the C30A but for my application I feel if it could/would be installed properly, it would do a swell job. The only reason I am going through the "hassle" to get one imported is the price. A USDM NSX in the same condition will sell from anywhere between 40-50k. I can have this one for merely half that by the time it reaches port in BC. Now that I've clarified that, correct me if I'm wrong A.S. Motorsports, but RL/Legend are C series V6s, how can I use those internals in a J series, are the configuarations even remotely the same?

 

[cwood1388]

In my opinion. Id really do as much time as I can crunching numbers and reading as much as I can on here.

Anything can be done with enough money. STMPO swapped a k20 into one of their nsx's. There's another guy who is swapping a LS7 into his. This just goes to show what can be done if you are a highly skilled fabricator. You were saying you were worried about the cost of parts being so expensive in Canada. While I could be wrong about this I seriously doubt that swapping a J engine for what you have right now would make up for the cost of parts.

I'm curious as to what your goals are with the car. This can probably gives us a much better insight as to what may be cheaper.

 

[jmillar691]

I'm sure I'll get the gears for jumping the gun on the J swap here aswell, so hear me out. The only reason I feel this is a valid (cost effective) swap is operating costs. Although I know the basics of the C30A, I personally can't vouch for their durability and have heard some horror stories (complicated, hard to work on, expensive parts) which makes the J sitting in the back of my garage seem sensible. And being that I have the motor plus tranny, it just got me thinking. The car is an automatic which I'm quite opposed too which is why I am considering the swap mainly. Is it easy enough to find a 5 speed C30A + tranny? And if I did, are these motors even durable enough to last? I don't plan on building it to be a 500HP monster and it will remain NA, I want it more for the fact that it's an NSX, IMO the pinnacle of Honda design. So if I can find a 50-100k mile 5 speed motor + tranny for sale, is this thing going to last?

 

[eyecandy]

http://www.nsxprime.com/forum/showthread.php?t=34107&highlight=mileage

look at some of the mileages here. plenty of high mileage cars running fine.

 

[jmillar691]

No disputing that. I've never driven an NSX so shame on me for not being a believer, they're Hondas afterall. However I have been looking for a motor + tranny combo and have came up with little to no results. Any reputable websites you would recommend outside of the classifieds section on this very site? Is 3-5k enough to buy a driveline for these cars?

 

[cwood1388]

I think comptech had a used 3.0 and trans. Nothing is ever hard to find here. at times you just have to know where to look. 3-5 is really relative. depending on the mileage and etc. You are also looking at doing a auto to 5spd swap as well correct?

 

[jmillar691]

Yes that is correct. I know the clusters are slightly different between the two if Im not mistaken and obviously console. But outside of an actual C30A motor + 5 speed tranny and the above listed, what else needs to be done to complete this? Motor mounts are readily available I know. Is suspension any different? ECU?

 

[macninja77]

I have complete changeover from a 92 with 100k pm me

 

[Honcho]

Before I go into detail, I apologize if this topic has been gone over before on these forums, I just feel that I have some more specified questions about this topic that I'm hopeful you NSX guys will be able to shed some light on.

Sitting in a container in Japan right now are 3 NA1 Honda NSX's. 2 silver in colour code, one is a '93, other is '94, third is a black '95 that has been modified much beyond my liking. The '93 is a documented, one owner, 42k all original. I can personally vouch for this exporter as I have purchased an S14 Silvia and a beat up '90 Skyline from him before. I inquired about the car and he sent me pictures and a we have reached an agreement on what I feel is a fair price. My main questions however are 1) what are the differences between a JDM NA1 NSX and a USDM? Obviously other than RHD, are there any glaring differences between them? 2) The car is automatic. It runs like a top and is in all original condition. I happen to have a j35z3 long block out of the USDM '08+ Accord with 6 speed transmission. I understand physically (size wise) the difference between the C series and J series engines (DOHC/SOHC, 90 degree block/60 degree block). Now outside of some custom fabbing that would have to be done to mount the engine, how would I possibly go about transmission? I have heard rumours that the NSX engine spins the opposite direction as opposed to every other Honda engine (pump side perspective). Is this feasable? Any insight or information from the board members here would be a huge help.

I understand your thought, but doing this swap will cost you more than doing a fully built 3.5L C30A stroker. The engine spins opposite, so you will have to mount it 180 degrees off of the C30. While J-series parts are cheaper, they are not that much cheaper. The cost difference compared to custom fabricating motor mounts, trans mounts, etc just to get this to fit will be minimal to negative. Then, you have to get the J35 to out-perform the C30A. This means a AEM ecu set for 8000 rpm operation, cams, valves, springs, high-compression pistons, light rods (maybe titanium if you can even find a fabricator), high performance oil and water pumps (since the OEM J-series cannot handle 8000 rpm) and accessories that can hold 8000 rpm. Though, maybe you could re-use the OEM NSX alternator and A/C compressor with custom brackets. When you are all said and done, $20,000 later, all that will be left that is original J-series is the block and head casts. Not worth it.

I think a better route is to find a rough C30A and 5-speed and build them to OEM+ state. Disassemble the entire engine and replace every seal and bearing. Use the SOS forged pistons at OEM compression. Then balance and blueprint the rotating assembly to NSX-R tolerance. Go buy yourself the Prospeed RDX injector/ECU mod for the top end and a SOS big bore throttle. This gives you basically a factory-new ~270 whp engine. Then, have a good NSX tech rebuild your 5-speed with new bearings, synchros and the JDM gear stack. Slap a SOS sport clutch on it to top it off. All of this will cost you less than a J-series swap and result in a SERIOUS NSX.

 

[TURBO2GO]

I understand your thought, but doing this swap will cost you more than doing a fully built 3.5L C30A stroker. The engine spins opposite, so you will have to mount it 180 degrees off of the C30. While J-series parts are cheaper, they are not that much cheaper. The cost difference compared to custom fabricating motor mounts, trans mounts, etc just to get this to fit will be minimal to negative. Then, you have to get the J35 to out-perform the C30A. This means a AEM ecu set for 8000 rpm operation, cams, valves, springs, high-compression pistons, light rods (maybe titanium if you can even find a fabricator), high performance oil and water pumps (since the OEM J-series cannot handle 8000 rpm) and accessories that can hold 8000 rpm. Though, maybe you could re-use the OEM NSX alternator and A/C compressor with custom brackets. When you are all said and done, $20,000 later, all that will be left that is original J-series is the block and head casts. Not worth it.

I think a better route is to find a rough C30A and 5-speed and build them to OEM+ state. Disassemble the entire engine and replace every seal and bearing. Use the SOS forged pistons at OEM compression. Then balance and blueprint the rotating assembly to NSX-R tolerance. Go buy yourself the Prospeed RDX injector/ECU mod for the top end and a SOS big bore throttle. This gives you basically a factory-new ~270 whp engine. Then, have a good NSX tech rebuild your 5-speed with new bearings, synchros and the JDM gear stack. Slap a SOS sport clutch on it to top it off. All of this will cost you less than a J-series swap and result in a SERIOUS NSX.

It's not THAT serious Honcho... LOL... You have 20HP over stock and a fresh tranny. I wouldn't call that serious. But I can see your points about the swap versus the C30. You are saving some weight though and I don't think it's anywhere close to 20K. Not sure how FI would work on the J.

 

[MetalSpikeRacing]

Why are you importing an NSX from Japan ? There is NSXs here in North America for sell .

Now the NSX community it's to be contaminated with RHD NSX too??!! Now I understand how my buddy felt when right hand drive supras where starting to imported in containers , this cars are a lot cheaper and beat up most of the time .

I can understand bringing a RHD GTR , because we don't have them here and they don't make them lhd anyways . It's annoying seen all those RHD rust buckets running around like we don't know they got them for cheap because of the same reason .

No to RHD NSXs , it will devalue our cars .

-MSR