My J swapped NSX...sorry for the wait. love or hate
- Thread starter Rogue MotorSports
- Start date
highly likely a torque monster...
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- 7 March 2008
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Ultimatley I want to surpass the 1000 hp mark. With the stock motor I was going to shoot for the low to mid 600s hp with upper 500s for torque.
I'm going to consult with ponyboy a little bit later this week, and might have a new beginning plan for the car. Anyone else is interested can chime in.
I was thinking of putting a completely stock motor in the car j32a3. It will have custom mounts, axles, and shift linkage. I would have an open track/ auto x day with the car where other enthusiasts could come down and drive it. Just to provide valued opinions on whether its worth while to even do the swap. We could do comparisons between the c30 c32 and the j32. ie: lap times, dyno, and car weight. I want the car to be driven extremely hard, and the motor abused ( I could, am, going to do it myself, but I want to give others the option to see what I already see in this setup).
After I discuss a little more with Shawn, I will put together a tentative plan.
This has to be one of the most interesting threads in a while.
on a other note, it should make the car sound different as well.
You can get that sound more high pitched due to the firing order overlap.
You can get that sound more high pitched due to the firing order overlap.
Interesting... More high pitched you say. A lighter yet bigger motor you say...
'60 degree V6 engines run smoother than '90 as the '90 angle makes the power stroke overlap incoherent giving a dead spot in power delivery this gives it a rough sound (try running a NSX on it's headers you'l know)
'60 degree has more stroke overlap thus more pistons doing work at one time (on there power stroke/down stroke) thus making trust.
This makes for less vibration and a smoother power curve.
if that overlap is big and the engine has so called dead points (e.g. piston is on intake stroke) the power delivery becomes more rough and there are more vibrations. (think V-Twin for a extreme vs a V12)
V6 is naturally unbalanced so much so that the big Honda C engine (C35A) uses a balance shaft to get smoother idle (I4's make wide use of these shafts)
'60 degree engines are much smoother negating the need for a external balancing (thus only flywheel and crank counter weights)
For example when you hear a american V8 you get that nice thumbing sound due to the cross-plane crankshaft balancing the engine down-low in the rev range (torque but won't rev as quick or high)
take a Maserati or Ferrari V8 it screams and has very smooth idle due to it's flat-plane crank (e.g. I4 engine) thus running in balance smooth, revving. (the flat plane sacrifice torque and low end driveability)
V12 and I6 are the ultimate balance engine in the practical world (i recall you need something like a 1440 piston engine to have a power stroke at every degree of crankshaft motion)
Boxer engines counteract each stroke giving them there distinct sound and power delivery (e.g. 911)
Might be a idea to listen to J engines on dyno's and listen to a Metro 6R4. (very comical but cool/quick '60 V6 car)
A Honda/Acura Legend demonstrates the roughness of the C engine excellently. (but posses a killer torque curve)
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- Joined
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Here is my j dyno. No cats 3 in exhaust to a straight through race muffler.
http://www.youtube.com/watch?v=4EHXT3W9suk&feature=youtube_gdata_player
http://www.youtube.com/watch?v=4EHXT3W9suk&feature=youtube_gdata_player
Rogue-
There is a market for this concept, but as I understand you come from the Accord/Prelude import drag racing world, there are a few NSX-specific factors you should understand before spending too much time or money on this project. First and foremost is the NSX is NOT a drag racing car. A new clutch job will run an NSX owner about $4,000, so multiple hard launches at the strip are not a favorite pastime of people who drive this car. Instead, the NSX is a car specifically designed to dominate on a road course where handling, braking and acceleration are all equally important- all while maintaining a reliable, comfortable to drive manner. In fact, most owners do not even track their cars, so your market really falls into the large group of NSX owners who do not race their cars, but feel its development has been left behind by Honda and would like more competitive performance.
Second is what NSX owners want from their car. In 1990, Honda actively poached customers of the Ferrari 348 to buy the NSX instead. Driving a 348 and then driving a NSX was an eye-opening experience. It was much more comfortable, it stopped better, the engine was smooth and exotic, and it was put together so much better. The NSX delivered the same exotic performance of the high—revving Ferrari without the headaches or huge price tag. For this reason, Honda sold thousands of them in those first few years.
As time went by, Ferrari and Porsche improved their cars, but the NSX pretty much stayed the same. When Honda debuted the vastly-improved J-series V6 engine in the late 90’s, the NSX strangely kept the old C-series. Why? Probably cost, but in any event NSX owners felt left behind. So what do NSX owners want? Well, in 1990 they wanted a Ferrari 348 that worked and was comfortable. Today they want a F430 or 458. Since Honda dropped the ball, the aftermarket has stepped in to try and make that happen, but has been limited to trying to make the C-series better, which brings us to item 3- your competition.
Comptech was the first to step in to keep the NSX comparable to other cars with their IEM engine package. But, even after changing cams, extrude honing the intake manifold, and other internal mods, they only managed about 270 whp. They gave up on that idea and moved to a screw-type supercharger kit that has since become the most popular way to get the NSX to compete. The supercharger adds about 60 whp to a stock engine and has been described by many as the perfect power level for a relatively stock NSX. Problem is, the C-series is not a really good platform for forced induction. It is a high-compression, open deck design. This makes sense, since the C30A was designed from the outset to be a free-revving, high RPM exotic powerplant comparable to those Ferrari uses. As engine management solutions matured in the 2000’s, several folks came out with turbocharger kits for the NSX that can deliver up to 900 whp, but these are very expensive and require rebuilding the engine. In addition, while delivering mega power, many owners (myself included) feel forced induction “ruins” the free-revving NA feel of the NSX and most owners do not opt for it for this reason.
Thus, the competition generally looks like this:
Basic 3.0 liter “all motor” build = $10,000 | 40 whp
CT Engineering Supercharger = $10,000 | 60 whp
SOS “C35A” 3.5 liter stroker with ITB = $20,000 | 80 whp
SOS/Angus/Lovefab Turbo Kits = $20,000+ | 100 to 500+ whp
The J-series is alluring to NSX owners because it represents the most modern Honda engine technology that is missing in the NSX. If you can deliver a J-series kit that (1) is plug-and play; (2) reliably runs to the factory limit of 8300 RPM; (3) produces more torque across the curve; (4) delivers at least 60 whp more than stock; and (5) costs less than $10,000, then I think you will have a winner on your hands. The turbo/boost route may give you bigger numbers, but your market will be limited in the NSX world. You should be aiming for the “on the fence” supercharger customers who want their NSX to drive like a new 911 or F430, but are concerned with boosting their stock engines, not the “Krazy Kustom” drag racers who just want a youtube video of their monster NSX destroying other cars at the strip.
I like my C30A and how my NSX drives, so I guess I am happy with Ferrari 348 level performance. But, for those owners who want a little bit more in a modern factory powerplant solution, I think you can help them- there are more than a few.
There is a market for this concept, but as I understand you come from the Accord/Prelude import drag racing world, there are a few NSX-specific factors you should understand before spending too much time or money on this project. First and foremost is the NSX is NOT a drag racing car. A new clutch job will run an NSX owner about $4,000, so multiple hard launches at the strip are not a favorite pastime of people who drive this car. Instead, the NSX is a car specifically designed to dominate on a road course where handling, braking and acceleration are all equally important- all while maintaining a reliable, comfortable to drive manner. In fact, most owners do not even track their cars, so your market really falls into the large group of NSX owners who do not race their cars, but feel its development has been left behind by Honda and would like more competitive performance.
Second is what NSX owners want from their car. In 1990, Honda actively poached customers of the Ferrari 348 to buy the NSX instead. Driving a 348 and then driving a NSX was an eye-opening experience. It was much more comfortable, it stopped better, the engine was smooth and exotic, and it was put together so much better. The NSX delivered the same exotic performance of the high—revving Ferrari without the headaches or huge price tag. For this reason, Honda sold thousands of them in those first few years.
As time went by, Ferrari and Porsche improved their cars, but the NSX pretty much stayed the same. When Honda debuted the vastly-improved J-series V6 engine in the late 90’s, the NSX strangely kept the old C-series. Why? Probably cost, but in any event NSX owners felt left behind. So what do NSX owners want? Well, in 1990 they wanted a Ferrari 348 that worked and was comfortable. Today they want a F430 or 458. Since Honda dropped the ball, the aftermarket has stepped in to try and make that happen, but has been limited to trying to make the C-series better, which brings us to item 3- your competition.
Comptech was the first to step in to keep the NSX comparable to other cars with their IEM engine package. But, even after changing cams, extrude honing the intake manifold, and other internal mods, they only managed about 270 whp. They gave up on that idea and moved to a screw-type supercharger kit that has since become the most popular way to get the NSX to compete. The supercharger adds about 60 whp to a stock engine and has been described by many as the perfect power level for a relatively stock NSX. Problem is, the C-series is not a really good platform for forced induction. It is a high-compression, open deck design. This makes sense, since the C30A was designed from the outset to be a free-revving, high RPM exotic powerplant comparable to those Ferrari uses. As engine management solutions matured in the 2000’s, several folks came out with turbocharger kits for the NSX that can deliver up to 900 whp, but these are very expensive and require rebuilding the engine. In addition, while delivering mega power, many owners (myself included) feel forced induction “ruins” the free-revving NA feel of the NSX and most owners do not opt for it for this reason.
Thus, the competition generally looks like this:
Basic 3.0 liter “all motor” build = $10,000 | 40 whp
CT Engineering Supercharger = $10,000 | 60 whp
SOS “C35A” 3.5 liter stroker with ITB = $20,000 | 80 whp
SOS/Angus/Lovefab Turbo Kits = $20,000+ | 100 to 500+ whp
The J-series is alluring to NSX owners because it represents the most modern Honda engine technology that is missing in the NSX. If you can deliver a J-series kit that (1) is plug-and play; (2) reliably runs to the factory limit of 8300 RPM; (3) produces more torque across the curve; (4) delivers at least 60 whp more than stock; and (5) costs less than $10,000, then I think you will have a winner on your hands. The turbo/boost route may give you bigger numbers, but your market will be limited in the NSX world. You should be aiming for the “on the fence” supercharger customers who want their NSX to drive like a new 911 or F430, but are concerned with boosting their stock engines, not the “Krazy Kustom” drag racers who just want a youtube video of their monster NSX destroying other cars at the strip.
I like my C30A and how my NSX drives, so I guess I am happy with Ferrari 348 level performance. But, for those owners who want a little bit more in a modern factory powerplant solution, I think you can help them- there are more than a few.
Honcho that's a very good write up and discussion spark.
As I do more and more research on the NSX, I'm wondering if it's the right car for me to get a few years down the road just because of how much it costs to maintain if you auto-x, track, etc. I still have yet to drive one, and thankfully hondacbx has offered to let me check his out, which I'll probably do spring 2013. This J series swap is intriguing to me because it opens up an avenue that might result in a less expensive experience with the NSX. I do understand the other side of the coin though from the purist standpoint.
Pardon my ignorance, but none of the J-series engines appear to have a high redline. Why? If you rebuild and balance the engine, couldn't the redline be increased?
As I do more and more research on the NSX, I'm wondering if it's the right car for me to get a few years down the road just because of how much it costs to maintain if you auto-x, track, etc. I still have yet to drive one, and thankfully hondacbx has offered to let me check his out, which I'll probably do spring 2013. This J series swap is intriguing to me because it opens up an avenue that might result in a less expensive experience with the NSX. I do understand the other side of the coin though from the purist standpoint.
Pardon my ignorance, but none of the J-series engines appear to have a high redline. Why? If you rebuild and balance the engine, couldn't the redline be increased?
To increase redline additional flowing and high lift cam's are required these are so far not available readily for J engines.
Back to Honcho, he's right I've been waiting for years to see the first NSX going J it was just a matter of time.
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Honcha, thank you for your valuable input. It was very well worded and makes complete sense. First and foremost I am doing this swap and build for myself. I have goals and dreams I am trying to accomplish. Second I want to show that other options are available. I work extremely hard for what I have. I am not building this to market a swap kit, or to convince one that the j series is any better or worse than that of the c series. I have driven a couple nsx's and other than being under powered I have no complaints. Building a suitable, reliable c engine has proven to be very costly. The cost of the build is a bit out of my income level. The way I see it, I can achieve similar results saving myself a lot of money.
The j series is not a high reving motor from the factory. To me the only logical reason is because its not needed. It produces plenty of power and torque to power the cars/trucks/suvs it was designed for. And with the proper gearing in the transmission Honda has the power where they deemed necessary. By adding an aftermarket valve train and a cam with different lift and duration I don't see why power can't be made past 8k rpm.
As far as the clutch. I'm not sure how much drag racing I will be doing with the nsx, as I have a dedicated drag car. A proper clutch for the type of driving is a must. I had a tilton twin disc on my last motor, and never had another clutch worry.
The j series is not a high reving motor from the factory. To me the only logical reason is because its not needed. It produces plenty of power and torque to power the cars/trucks/suvs it was designed for. And with the proper gearing in the transmission Honda has the power where they deemed necessary. By adding an aftermarket valve train and a cam with different lift and duration I don't see why power can't be made past 8k rpm.
As far as the clutch. I'm not sure how much drag racing I will be doing with the nsx, as I have a dedicated drag car. A proper clutch for the type of driving is a must. I had a tilton twin disc on my last motor, and never had another clutch worry.
Honcho: perfectly stated.
I hope the developer/OP takes your advice and sees the potential here for your proposal. This project has the potential to be *revolutionary* in the NSX world if managed correctly. However, it may be one man's custom vision rather than this business proposition (hoping its not). I'm ok with a boosted J swap but I do see many owners refuse to use a turbo. Even less are interested in a 1000hp NSX. I actually would still prefer a 375-400 whp high revving J motor to a lower revving 500+ whp turbo motor even though it'd be slower. I would sign up for such a package rather than rebuild my NSX motor for boost. So far only SOS has proven long term to have their fingers on the pulse of the NSX owner base. They would be a great consulting source though Honcho has it summed up nicely already. This can be the next frontier for NSX owners if you really look at what they want and provide a tailored product range to fill those desires. Exciting!
I hope the developer/OP takes your advice and sees the potential here for your proposal. This project has the potential to be *revolutionary* in the NSX world if managed correctly. However, it may be one man's custom vision rather than this business proposition (hoping its not). I'm ok with a boosted J swap but I do see many owners refuse to use a turbo. Even less are interested in a 1000hp NSX. I actually would still prefer a 375-400 whp high revving J motor to a lower revving 500+ whp turbo motor even though it'd be slower. I would sign up for such a package rather than rebuild my NSX motor for boost. So far only SOS has proven long term to have their fingers on the pulse of the NSX owner base. They would be a great consulting source though Honcho has it summed up nicely already. This can be the next frontier for NSX owners if you really look at what they want and provide a tailored product range to fill those desires. Exciting!
Ah that's what I was afraid of Rogue! I hope someone with enough expertise will still develop this and pursue it as a business opportunity.
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After I finish this one and testing is compelete I will produce a kit if desired. A few things that are a must if the kit is going to be produced. Factory mount utilization, a.c. retention, and gauge cluster fully operational. With the use of the stand alone, and possibly different sensor type on the vss and for tach signal those might be trickey. I will pursue those issues when they develop.
Cool. Please look into valve train and cams if possible bc the motor should definitely be high revving for this car! No reason to turn this into a corvette formula 
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Cool. Please look into valve train and cams if possible bc the motor should definitely be high revving for this car! No reason to turn this into a corvette formula
Valve train and cams are available. Through kms and bisimoto. There is a lot of speculation out on the cam regrinds such as the hardening process and longetevity. Once I use the product I will have more info available. I can say that itb's are in beta production.
Cool. Please look into valve train and cams if possible bc the motor should definitely be high revving for this car! No reason to turn this into a corvette formula
I'd be fine with a 7k redline and boost.
if the said 3.6L build puts out 340whp at 6800rpm, that sounds plenty to me.
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If members here believe this is a worthy investment and if rogue proves it all bolts and fits and runs good. I would be willing to throw my hat in making the mounts. I am a CNC programmer and machinist and love this kind of work, plus....I was thinking of going this route for a long time, but well...my heart beats to keep stuff stock if it can be done. However if NSX with a fried motor etc, heck yeah. I also have been looking to purchase and NSX in the spring but have another build going on, but if someone found me a good chassis to be saved I would gobble it up.
Also, the stock camshafts work fine.(IE: swapped of course..)
Also, the stock camshafts work fine.(IE: swapped of course..)
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Just my $.02, but why don't you contact HPD about what they did for mounts in their car. If they made it work, clearly it's possible. I'm willing to bet they know a thing or two about it and could shed some light on that issue.
I'm subscribing to this. It seems that there could potentially be much to gain from a plug and play setup for the J3xA setup in these cars.
I'm subscribing to this. It seems that there could potentially be much to gain from a plug and play setup for the J3xA setup in these cars.
I'm checking this thread everyday for some updates, if this work I would buy another nsx to put the j series in
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Once I have mine finished we will be more able to determine if the swap is worthwhile. At that point I may contact you for some cnc help
I will try to contact hpd sometime to see if they could be of assistance
I sincerely apologize for the lack of updates. I will be posting a few updates soon.
