FX500 car going back to the shop for repairs?

[NSXTASY_MD]

FX never ceases to impress me. The way they PRO-actively took matters into their own hands to get you back on track is a tribute to a true tuner* Honestly, its even more than that...I love their attitude & professionalism. I was contemplating going with a computech supercharger for the direct plug & play aspect to them...not having to deal with a tuner. Reading this thread makes me WANT to take my business to them. I always preferred the hardcore 3.3L N/A stroker kit anyway ...keep up the standard guys you'll be hearing from me!


--- Kevin D.

 

[peiserg]

condolances, KGP.

as if i have to say it, dam that really blows. well, nice they are backing up the product for you, at no insignificant cost to themselves i'm sure.

Looks like the road to FI is dark and twisted indeed....

 

[MiamieNeSeX]

condolances, KGP.

as if i have to say it, dam that really blows. ...

Actually its the complete opposite.

Armando

 

[BryanZublin]

Re: Pressure Drop

(snip)The important thing for potential turbo owners to keep in mind is that this is not a direct result of adding forced induction as such.

Does the FX500 kit use the stock crank bearings? If so, then how can you be so sure of your statement above? The FX500 kit doubles the horsepower of the NSX engine and will increase the stress on the crank bearings by a significant amount. This could driectly cause premature bearing failure.

 

[sjs]

Re: Pressure Drop

Does the FX500 kit use the stock crank bearings? If so, then how can you be so sure of your statement above? The FX500 kit doubles the horsepower of the NSX engine and will increase the stress on the crank bearings by a significant amount. This could driectly cause premature bearing failure.

Fair question. However, the bearings are not stock. I'll leave it to FX to give the details, but they should not have a problem with the extra power. In fact, the stock bearings should not fail at those power levels and have been up to the task on other engines, as I would expect. There is the possibility that one or more of them were faulty, but that still can't be blamed on the forced induction. Main bearings really should not be the weak link at these power levels.

 

[matteni]

Hi Gene,

Haven't speant much time here this summer/fall and just saw this. Bummed out for you brother. Chin up - this is all little stuff and we both have real important stuff that we would push our cars off a cliff for.

Surely you will get it back soon and FX does sound a little different then the last FI tuner experiance you had.

 

[xsn]

Reading this was depressing. It has been a couple weeks - is there a diagnosis yet?

 

[KGP]

A few main bearings need to be replaced. Thank goodness no rod bearings or rod damage. Looks like the crank will be okay with a micro polish, but waiting on some measurements to know for sure.

 

[Elite]

Did they figure out the cause for the loss in oil pressure? Simply bearing wear?

 

[nsxbuilder]

Team,

The "rule" on oil pressure for our little motors is maintaining a minimum of 10lbs per 1000 rpm, or no less than 80lbs at 8000rpm. Easy. My car with 21 feet of #12 (3/4") braided front to back sits at 82 at any rpm over 3000. Life is good.

The problem is taking the HP and torque of the motor above the limit that the crank bearings can use that little mico layer of oil to keep the metal parts away from eash other. Higher oil pressures will help (go see the Mods-Oil Cooler section of my site for all the details) but have an upper limit as well at around 100lbs - then apparently there are seals and other oiling mechanisms that can't take the pressure, or so I've been told by RealTime. Also, you should have a dry sump for safety and longevity reasons.

I guess that if you maintained 12lbs of oil pressure for every 1000rpm you could run pretty high HP, but for how long and under what conditions I have no clue. All I know is that 315hp with 253ft/lbs at the wheels and drive my car pretty hard and it's been bulletproof (so far). Add 100+ to those numbers and the rules just may not apply anymore.

-Ed
www.nsxbuilder.com

 

[Arata]

How about a little bearing 101?
Or does this constitute the dreaded Monday morning QB?
I am not an expert on bearings, these thoughts are based on by experiance building and seeing engines, I have built over 500 Honda Motorcycle RACING engines.
There are a number of factors that determind a bearing ability to withstand failure.
One as very well put by nsxbuilder is oil pressure.
Another is the quality and design of the bearing, most Honda bearing that I have seen have been very good.
So unless they are using a different brand or type of bearing they are limited to what everyone has in their engine now. Very good stock Honda bearings.
The two big ones are the width and the diameter of the bearing, this is a little harder to change, as new rods and new or modded crankshaft, and a modded crank is rarely as good as a machined forged or cast crank.
So back the the width, the wider the surface area the more load the bearing can support, but more HP robbing friction is produced, so it is a fine balance, the same with Diameter, the larger the better for lift, the larger the worse for power.
Another factor is lift span, a bearing designed for 1/6 (1 or 6 cylinders) of 290HP may be designed to last 100,000 to 150,000 miles under normal use and regular oil changes, but take that same bearing and double the HP, it may last for a period of time, but it will be greatly reduced, as little as a few hundred miles.

 

[Troll]

[..]
Another factor is lift span, a bearing designed for 1/6 (1 or 6 cylinders) of 290HP may be designed to last 100,000 to 150,000 miles under normal use and regular oil changes, but take that same bearing and double the HP, it may last for a period of time, but it will be greatly reduced, as little as a few hundred miles.

And thats the exact reason why i would never mod the engine of my (future ) nsx. 270HP are enough (for me) you have to visualise that, 270 horses controlled by one person. I dont think you have to ruin your engine squeezing some more of those poor lil´ fellas in your engine

 

[Troll Patrol]

you have to visualise that, 270 horses controlled by one person. I dont think you have to ruin you engine squeezing some more of that poor lil´ fellas in you engine

Can't figure out what the heck you're saying, so I'm not sure I can call you a true Troll or not.

 

[NSXWIND]

Can't figure out what the heck you're saying, so I'm not sure I can call you a true Troll or not.

I think he is saying that each liter output close to 100 HP, which is a decent amount of HP from each liter. It doesn't need any mod for more HP to exhaust the engine. Hey troll, I hope I’ve catch your metaphor.

btw sorry for going off-topic

 

[BadCarma]

All I know is that 315hp with 253ft/lbs at the wheels and drive my car pretty hard and it's been bulletproof (so far). Add 100+ to those numbers and the rules just may not apply anymore.

-Ed
www.nsxbuilder.com[/QUOTE]

I am with you Ed, give me a modest shot of spray and sleep well at night

 

[sjs]

Guys, the bearings are not the weak link, and all this under-informed chatter is a disservice to the community. If you were tracking a 500+ RWHP NSX day in and day out so it was constantly running at high torque, then maybe you start watching them carefully. But few street cars are at high loads for more than very brief spurts a tiny fraction of the time and the rest of it‘s life is easy. Properly built, the bearings would be far down my list of concerns on an FX-500, even the way I drive. So please, find something else to fret about.

 

[Arata]

Are you back on the road yet??
Still no idea what caused the failure??

 

[KGP]

Have an idea? Yes. On the road? No. I will leave it to FX to post, as they are the ones who have examined the car, along with an outside expert that was brought in for evaluation.

 

[Factor X Motorsports]

Have an idea? Yes. On the road? No. I will leave it to FX to post, as they are the ones who have examined the car, along with an outside expert that was brought in for evaluation.

As Sjs has stated the bearings are not the problem. The oil cooler system caused the failure. KGP will be back up and on the road shortly. Thanks for the patience big guy.