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Engine Failed, CTSC Damaged

NSXROC said:
I was wondering the same since my low boost really wasn't making that much more HP compared with others.

The belt was tight alright. The belt was checked every 1k mile by Zahntech.
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For one, do you already know for sure that it was premature detonation that caused your engine failure?? Could it be something else perhaps.

I am asking this because, lately, I have been considering upgrading my car to a low-boost CTSC. CTSC because it seems to be a reliable and proven system, low-boost BECAUSE I don't want any problems.
330-335 RWHP is more than enough in my opinion to put the NSX back in the same league as practically any other high-end sportscar (Porsche 911, R8, RS4, M3 etc.) and that is enough for me.
Now, your misfortune is making me reconsider all of this again...
 
exactly.
i guess the prudent thing when spending 10k on a supercharger is to spend 1 more thou and get the right pistons.
 
MvM said:
For one, do you already know for sure that it was premature detonation that caused your engine failure?? Could it be something else perhaps.

I am asking this because, lately, I have been considering upgrading my car to a low-boost CTSC. CTSC because it seems to be a reliable and proven system, low-boost BECAUSE I don't want any problems.
330-335 RWHP is more than enough in my opinion to put the NSX back in the same league as practically any other high-end sportscar (Porsche 911, R8, RS4, M3 etc.) and that is enough for me.
Now, your misfortune is making me reconsider all of this again...
Click to expand...

Don't hold ur breathe on Porsche.

I was invited to a Porsche pre Le Mans party last night with the drivers there.

GT3RS and 911TT. I just figured that good bolt on mods for NA will get u around and just live with the notion that our cars were designed in the 80's based on technology available back then.
 
Sorry to hear the bad news.

This is not the first time that we have heard of issues with the autorotor in cold temps. Remember CT actually stopped shipping the units because once the temp dropped, the guys in CA, who also get a drop in octane rating at the gas station in the fall, started to notice detonation on their cars.

Colder air. Lower octane. Increased detonation.

Then the ACM came out and that largely addressed the issue by making the engine run richer. Look at my black bumper!

I heard from CA shops that the problem was not completely resolved with the ACM and they strongly suggested that since Im in TO, that I get an EMS solution. CT suggested to me that I stay off the gas for an extended period of time when its cool out (Im in Toronto) to let the manifold heat up. Im not talking wait for the needle to raise (which takes a few minutes in my car), Im talking 20 minutes. CT also told me that no matter the temperature, the safest CTSCd engine is one thats hot as hell on the track.

The issue is that the stock computer pulls timing back with heat. When its cool out, and when youve got lower octane in there, you really want that pull back to avoid running lean. If you're on the gas when its coolish out (high oxygen)with a coolish engine (advanced timing) without high (93/94+) octane in the car, youve got a higher chance of detonaing.

Sounds like you got stung; crap.

For the others:
When its cooler outside, NEVER put anything less than high octane in the car. My personal feeling based upon absolutly no evidence is that 91 is not high enough when its cold.
Dont consider your car warmed up until youve been in it for 20 minutes.
Get your A/Fs checked. Ive got the AEM guage in my car for my sanity.
 
I'm afraid of this happening to me! I have a CTSC as well but the old whipple type. How can I measure my A/F ratio (it's a 91 thus non-OBDII)? When I rev it, I seem to hear pinging (detonation?), but am not sure.
 
The GruppeM exhaust is very raspy at high revs (love it!!), so I can't tell is it's an exhaust sound or truly pinging. Since installing the GruppeM (no cats) yesterday, I seem to be getting some black smoke at high revs (rich?). Is there any way to verify the A/F ratio on a 1991?
 
Please don't take this the wrong way, but I do not understand when putting a $10K CTSC kit on a car, why people don't invest another $300-500 in a wideband a/f gauge and/or a detonation measuring device.

A/f gooiing wrong with fatal detonation as a result, I think is the most common cause for engine failure on a car with aftermarket turbo or SC kit.

In most cases the a/f is ok when kit is installed and dynoed, but later on in life when either a fuelpump wears or a fuelfilter cloggs up, disaster strikes.

With a a/f and-or knock device there is a good chance to see this happening in time to prevent damage.

I have a PLX R-500 ready and waiting for install when I get my CTSC NSX in a few weeks time.
 
MvM said:
For one, do you already know for sure that it was premature detonation that caused your engine failure?? Could it be something else perhaps.
Click to expand...

No, we have not identified the real causes yet.


C-speed said:
NSXRoc: Sorry to hear about your misfortune... I believe I drove past you when it happened... I made a post here:

http://www.nsxprime.com/forums/showthread.php?t=95371

Was it you?
Click to expand...

Yes, that was me. It was a bad spot to have the car stalled. Luckily one trooper came and helped pushed the car to a safer spot.

alvav said:
I'm afraid of this happening to me! I have a CTSC as well but the old whipple type. How can I measure my A/F ratio (it's a 91 thus non-OBDII)? When I rev it, I seem to hear pinging (detonation?), but am not sure.
Click to expand...

Get the wideband AEM AF Ratio gauge. I will be getting one of those.

rsevo6 said:
Please don't take this the wrong way, but I do not understand when putting a $10K CTSC kit on a car, why people don't invest another $300-500 in a wideband a/f gauge and/or a detonation measuring device.

A/f gooiing wrong with fatal detonation as a result, I think is the most common cause for engine failure on a car with aftermarket turbo or SC kit.

In most cases the a/f is ok when kit is installed and dynoed, but later on in life when either a fuelpump wears or a fuelfilter cloggs up, disaster strikes.

With a a/f and-or knock device there is a good chance to see this happening in time to prevent damage.

I have a PLX R-500 ready and waiting for install when I get my CTSC NSX in a few weeks time.
Click to expand...

I agree with you totally. I have DEFi boost and fuel pressure gauges along with the Controller II unit. I thought the setup was adequate.
 
alvav said:
The GruppeM exhaust is very raspy at high revs (love it!!), so I can't tell is it's an exhaust sound or truly pinging. Since installing the GruppeM (no cats) yesterday, I seem to be getting some black smoke at high revs (rich?). Is there any way to verify the A/F ratio on a 1991?
Click to expand...

Black smoke because you don't have cats....:)
 
The cause has been determined

Pre-ignition/Detonation was not the cause here, Lean issues most commonly manifest themselves in broken ringlands and broken spark plug tips.

However I would highly recommend running a wide-band A/F ratio gauge with a warning indicator to warn of lean issues on any boosted NSX.

The cause of this unusual failure is a broken crankshaft at the 3/6 bearing journal area.
 

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Last edited:
Most likely this crank had a casting flaw that was not able to deal with the added stress of FI.


Many NSXs are out there running 350hp without issues like this.
 
That is very unusual. The stock crank has been proven to withstand much much more power then what is being made by this car. That just looks like luck of the draw unfortunately.
 
hi mate sorry been workin nights
ok pm sent plus i need your full address so i can get my garage to see how much postage will be
email all details pls
i have just email you some pics
[email protected]
thx amo
 
zahntech said:
The cause of this unusual failure is a broken crankshaft at the 3/6 bearing journal area.
Click to expand...

The real story.
I enjoyed all the speculation. It's always entertaining to read what folks conclude when they have no first hand knowledge of the situation.

John,
Was there any history for this motor that might of helped develop this condition?
 
Next is why again.

Most engine builders will check for clues by locating color patterns left on the crank journals, bearing caps and markings on the cylinder walls.

From what I can see, my guess is an oiling issue which would lead me to check the quality of the oil that was in the car and oil system.
 
Wow, crankshaft failure? I've never ever heard of that happening in an NSX. Man, I'm real sorry this happened to you. Good luck finding a replacement crank...they're worth their weight in gold if you do.
 
Hoover said:
Next is why again.

Most engine builders will check for clues by locating color patterns left on the crank journals, bearing caps and markings on the cylinder walls.

From what I can see, my guess is an oiling issue which would lead me to check the quality of the oil that was in the car and oil system.
Click to expand...


Engine oil was changed a week before the incident. I used only Mobile One synthetic oil. Less than 20 miles driven since that oil change.
 

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