No talk about the PURE900 turbo upgrade?

[Shenanigans]

No thread on it yet but Pure Turbos announced their Pure900 upgrade for the NSX which they say is 850+ whp capable: https://www.pureturbos.com/product/acura-nsx-nc1-pure-900/

I mean just look at the difference:

This should be exactly what the NSX needs assuming the tuning is there. The fuel system shouldn't have any problem as the port side should be able to handle things or even be upgraded for E85 I would think.

The transmission on the other hand...

 

[Ion]

It’s happening isn’t it. `

 

[Ignition_Key]

$5K upgrade, not cheap by any means... This definitely requires a tune and the only tuning options we have is the K tuner

 

[Shenanigans]

For a car with production numbers this low that has no other turbo upgrade options... seems quite reasonable. I would be happy to have the option. It may lead to others now.

 

[Ion]

$5K upgrade, not cheap by any means... This definitely requires a tune and the only tuning options we have is the K tuner

That’s one way of looking at it. Another way of looking at it is a year ago we had no upgraded turbo option and no custom tuning solution (just JB4) and now we have PURE900 turbos, Ktuner and ethanol tunes + Dodson clutches in the works. Can’t wait to see what this platform can do.

 

[stuntman]

Those are Big-A$$ Wheels. Could be quite laggy.

Do we know how much power the stock block can handle?

 

[Shenanigans]

Considering they raced the motor without changes and it is a 3.5 liter and it has forged internals except for the cast aluminum pistons the block is really not in question at this level. I'd be more concerned about the trans and pistons.

 

[stuntman]

Considering they raced the motor without changes and it is a 3.5 liter and it has forged internals except for the cast aluminum pistons the block is really not in question at this level. I'd be more concerned about the trans and pistons.

Who raced it?

At "what level"? 900hp? The stock cast pistons and head gaskets and block can handle that?

("Block" was referring to the "longblock")

 

[Ion]

JNC1 has forged connecting rods and crank and dry sump but pistons are cast aluminum for some reason which is unfortunate. S2000 and first generation NSX had forged pistons and this would be preferable when pushing limits.

Stock JNC1 is used in GT3 and can withstand several hundred back to back laps at race pace so it’s clearly a stout engine but increasing power to 850whp+ will definitely strain things. Let’s hope it stays together given the six figure cost to replace.

 

[Shenanigans]

Who raced it?

At "what level"? 900hp? The stock cast pistons and head gaskets and block can handle that?

("Block" was referring to the "longblock")

Raced internally stock in GT3 and won the championship in 2019.

As stated above, forged rods and crank with I believe three dry sump pumps.

The S2000 made 700+ whp on stock internals. The NC1 should be capable of more.

 

[stuntman]

Raced internally stock in GT3 and won the championship in 2019.

As stated above, forged rods and crank with I believe three dry sump pumps.

The S2000 made 700+ whp on stock internals. The NC1 should be capable of more.

GT3 cars are ~500bhp. Theres a big difference in cylinder pressures when increasing that number by 50%. I doubt that F20/22 would last a proper race weekend and likely barely survived that Dyno pull.

 

[Shenanigans]

GT3 cars are ~500bhp. Theres a big difference in cylinder pressures when increasing that number by 50%. I doubt that F20/22 would last a proper race weekend and likely barely survived that Dyno pull.

The stress on a race car is far more than a street car that isn't going WOT all the time. The GT3 car is 500 hp, yep, and that is what the NSX motor produces easily without the electric motors assisting. The fact they raced a factory stock NC1 is rather amazing and shows they built it with race competition in mind from the onset.

Additionally, plenty of six cylinder turbo cars are making 800+ whp these days. Even 3.0 liter BMW's are doing it on stock internals.

Honda builds great motors and considering everything is forged other than the pistons you likely would only need forged pistons if really wanting to push it. I think NSX owners have plenty to be optimistic about here.

 

[docjohn]

...well for NC1 Cosworth produces them and the PMC builds them..Cosworth got a very nice $ infusion from Honda because of it..their facilities before hand were getting long in the tooth..

 

[Shenanigans]

...well for NC1 Cosworth produces them and the PMC builds them..Cosworth got a very nice $ infusion from Honda because of it..their facilities before hand were getting long in the tooth..

Doesn't Cosworth just cast the block and heads?

 

[docjohn]

Doesn't Cosworth just cast the block and heads?

where does the reciprocating assembly come from?

 

[Shenanigans]

where does the reciprocating assembly come from?

Not sure but aren't the motors assembled outside of Cosworth?

 

[docjohn]

the parts come to pmc, the select (cream of crop) craftsman assemble and balance the ice once mated to the DCT...The turbos and all plumbing are from various places.

 

[stuntman]

The stress on a race car is far more than a street car that isn't going WOT all the time. The GT3 car is 500 hp, yep, and that is what the NSX motor produces easily without the electric motors assisting. The fact they raced a factory stock NC1 is rather amazing and shows they built it with race competition in mind from the onset.

Additionally, plenty of six cylinder turbo cars are making 800+ whp these days. Even 3.0 liter BMW's are doing it on stock internals.

Honda builds great motors and considering everything is forged other than the pistons you likely would only need forged pistons if really wanting to push it. I think NSX owners have plenty to be optimistic about here.

Cylinder pressures are cylinder pressures. Just because an engine is reliable at 500hp in endurance racing does not mean it will be durable at 800whp on the street. Engines that "can" hold together for a Dyno queen pull are often on borrowed time where at some point, a pull on the street or Dyno causes the block to quickly become ventilated.

There is always a point of weakness, whether it's the piston, head gasket, rods, block, etc... who here is pushing big power through these engines to find those limitations?

 

[Ion]

I’m by no means an expert on engine building but I fail to understand why a bespoke six-figure GT3 racing engine co-developed with Cosworth does not have forged pistons from the get go? In higher power and forced induction applications forged is the way to go. S2000 and First generation NSX blocks hold a lot of power in stock form but they have forged connecting rods AND pistons. At least the rods are forged on JNC1 as this is common point of failure on cars like GT-R when torque is above 600, but we don’t know the limit of these pistons.

The problem is if you blow an engine, it’s much more expensive than building it before catastrophic failure as nearly everything is trashed if a piston / rod fails. You could preventatively replace the pistons but what bugs me about this is the following. The JNC1 was originally hand assembled by workers with an average of three decades of experience. From an article online I found “they used GPS-tracked torque tools to make sure (and record) all of the JNC1’s 547 fasteners are happy in their slots. They also have three multi-spindle nut runners to level out tensions, after which they run the assembled engines for an hour, listening to foreign noises via a stethoscope at up to 4000 rpm. Having completed the break-in procedure, Acura finishes the build by balancing the engine to spec with different weighted bolts”. You’d be hard pressed to find an engine builder to reassemble the engines with forged pistons that has this level of experience and attention to detail.

With a conservative tune and no sharp torque spikes I think block will likely be fine with 7-800whp, but I’d certainly sleep better at night if pistons were forged.

The more I read, I think clutches will be the weakest link. At least Dodson is working on upgraded clutch kit but no word yet on pricing or availability.

 

[Shenanigans]

Cylinder pressures are cylinder pressures. Just because an engine is reliable at 500hp in endurance racing does not mean it will be durable at 800whp on the street. Engines that "can" hold together for a Dyno queen pull are often on borrowed time where at some point, a pull on the street or Dyno causes the block to quickly become ventilated.

There is always a point of weakness, whether it's the piston, head gasket, rods, block, etc... who here is pushing big power through these engines to find those limitations?

Actual motorsport use with a factory stock motor is a great indicator as to the engine being reliable and stout. It does not necessarily tell you what the limit is but it certainly tells you this is a motorsport based street motor that can take the abuse of a full season of real racing. It's certainly a positive when assessing the motor and very impressive.

The S2000 revs to 9k rpm and that stress grows geometrically. The NSX doesn't rev anywhere near as high. Also, the S2K didn't make 700+ whp right off the bat. The tuning evolved as it will here.

Again, in this day and age it isn't unheard of to see 1000+ whp cars on stock internals.

I have a tuned six-cylinder car with less displacement making ~700 whp on stock internals that I beat on. I personally would bet on the NSX exceeding that comfortably. I wouldn't just assume a motor would blow when we are in the golden age of horsepower and tuning.

You seem to be taking a negative view whereas I am taking a positive one of platform capability. Until somebody does it this is all just speculation but based on what I read the NC1 is capable of being a formidable tuning platform.

You certainly don't have to tune or try to get there but the prospect of tuning being available and these turbos being available definitely has the NSX piquing my interest as out of the box IMO it's too far behind its competition.

 

[Shenanigans]

The problem is if you blow an engine, it’s much more expensive than building it before catastrophic failure as nearly everything is trashed if a piston / rod fails.

Not necessarily... check this out: https://www.ebay.com/itm/1665578275...:Acura&hash=item26c79ec208:g:fkUAAOSwyKplOWFr

Want to split it and send the pistons to someone to make forged versions?

 

[Honcho]

If you really want to know about the potential of the JNC1, I'd recommend reaching out to any of the current GT3 race teams that run pretty much the same engine that is in the production cars. They have more performance data than anyone, including Acura, at this point. Also, talk to Shad at Driving Ambition, as I believe he's had a few JNC1 engines apart.

My understanding is that the engine revs were kept lower to keep the system reliable for 12 and 24 hour races. It undoubtedly can support more revs, but it will cut into reliability in a way that Acura wasn't willing to risk. There is real money, sponsorships, brand rep, etc. on the line in those races. Like any engine, the JNC1 was designed to a certain performance/cost spec requested by the manufacturer. It was not designed to meet the needs of the tuner community and I doubt anyone at Cosworth was thinking about slamming big turbos in there to try and hit a dyno number for bragging rights in social media. That said, the GT3 engines do use slightly bigger turbos, so we know they at least considered more power in the design. Also, the platform has been incredibly successful in both GT3 and Super GT in Japan, so their design choices have been vindicated.

That said, I think it would be cool to explore the potential of the engine, but it's going to be extremely expensive to go down that road...

 

[Ion]

Not necessarily... check this out: https://www.ebay.com/itm/166557827592?fits=Model:NSX|Make:Acura&hash=item26c79ec208:g:fkUAAOSwyKplOWFr

Want to split it and send the pistons to someone to make forged versions?

Yeah, I’ve seen the inexpensive JNC1 engines on eBay from wrecked NC1s as well and this was in the back of my mind when being first inline for Ktuner. The only thing I can figure is law of supply and demand. At current power levels JNC1 is EXTREMELY reliable and there aren’t many NSX owners in general let alone ones looking for new engine so demand is likely low. Once we all start slapping bigger spooly boyz on, it will be interesting to see if affordable second hand engines can still be sourced easily. If I had the space and the WAF (wife acceptance factor) it would be tempting to buy a second hand engine and trans to keep on hand as an insurance policy. If you blow the original, you could build the spare before replacing.

In the event your engine blows and you can’t source a used one from eBay, here is cost for biggest items, new block and heads, excluding labor costs and other miscellaneous parts that should be replaced after a failure.

 

[Ignition_Key]

The JNC1 was originally hand assembled by workers with an average of three decades of experience. From an article online I found “they used GPS-tracked torque tools to make sure (and record) all of the JNC1’s 547 fasteners are happy in their slots. They also have three multi-spindle nut runners to level out tensions, after which they run the assembled engines for an hour, listening to foreign noises via a stethoscope at up to 4000 rpm. Having completed the break-in procedure, Acura finishes the build by balancing the engine to spec with different weighted bolts”. You’d be hard pressed to find an engine builder to reassemble the engines with forged pistons that has this level of experience and attention to detail.

Not necessarily... check this out: https://www.ebay.com/itm/166557827592?fits=Model:NSX|Make:Acura&hash=item26c79ec208:g:fkUAAOSwyKplOWFr

Want to split it and send the pistons to someone to make forged versions?

Interesting proposal, but the real question would revolve around the labor intensity of replacing the piston. Additionally, would the mechanic ensure adherence to all the factory specifications and precision that ACURA engineers meticulously followed during the engine's assembly?

If you really want to know about the potential of the JNC1, I'd recommend reaching out to any of the current GT3 race teams that run pretty much the same engine that is in the production cars. They have more performance data than anyone, including Acura, at this point. Also, talk to Shad at Driving Ambition, as I believe he's had a few JNC1 engines apart.

My understanding is that the engine revs were kept lower to keep the system reliable for 12 and 24 hour races. It undoubtedly can support more revs, but it will cut into reliability in a way that Acura wasn't willing to risk.

HONDA, like other Japanese manufacturers, typically adopts a conservative approach, prioritizing long-term performance over big HP numbers and short-term engine failures. With a proper tune, particularly focusing on easing in the torque, the stress on the engine's internals can likely be managed effectively. As Shenanigans pointed out, many modern cars can handle up to 1000 wheel horsepower on stock internals, provided it's done correctly.

 

[docjohn]

I'm going whistle tips and baseball cards in the spokes...