UPDATED 8/22: See my last post for final dyno
I finally picked up my NSX yesterday from the shop with my new Autorotor installed. The shop doesn't have a dyno, so even though it's supposed to be plug and play, I babied it home until I can get it tested.
Turns out that was a very smart thing to do.
I took it to a DynoJet this morning. Below are the details of the results. My plan is to take it to Autowave on Monday morning if they are free and see if they can find the culprit. In the meantime, I would love some suggestions on what it may be. I've looked at some older threads, and I'm sure that some of you may have had a similar issue before and found the problem.
Attached is the graph of A/F and HP/Torque. You'll see that it stops at just over 5K RPMS. It seems to start OK, then slowly rises until I hit 13 at 5K RPMS, which is when they let off the gas as its too lean. They tried adjusting the Fuel Pressure regulator, but it seemed to have little to no effect.
Any ideas on what may be causing the fuel starvation as the RPMs climb? Keep in mind this is a 92 and many parts have never been replaced. I just had a complete service done - Timing belt and water pump, all seals and gaskets replaced, all hoses replaced, all fluid flushed, and spark plugs changed. The timing belt and water pump was original!
So that tells me that the fuel pump, injectors, anything else that wears over time is very likely an original part and 17 years old. A full leakdown was done and it was at 10%, and that is with the engine cold. This was all checked and done before the Supercharger was installed.
I can only guess that since this is a bolt-on, and assuming it is installed completely correct, there may be something old or malfunctioning that needs to be replaced that is causing this to happen. I am figuring that Autowave is a good place to go since they have a Dyno AND they know the NSX and can find and replace whatever is causing the problem.
In the meantime, any suggestions are appreciated. I will keep this thread updated as the problem is hopefully resolved, and what ends up being the culprit. Hopefully it will be educational for me and anyone else that ever may have this problem.
This is a low boost kit and their gauge showed 6lbs on the dyno. I want to keep the car smog legal and do not want AEM management for now. I don't want to bandaid the problem with an aftermarket ECU that compensates for this problem, but find what part is malfunctioning to cause this. Once it's running properly on a low boost kit, I may consider the upgrade in the future. So I am running lean at only 6lbs, which is low for the Autorotor from what I have read here. They placed the sensor in the tailpipe for the readings. When I picked up the car, the idle was a bit lumpy, but since then it seems the ECU has adjusted and it's pretty solid now. The power curve seems so perfect and smooth, and yet the A/F gets out of hand over 5K.
Mods that may effect what is happening.
Stock airbox
Comptech Headers
Taitec GT Lightweight
Stock Cats
No other power mods
Looking forward to getting it resolved and finally enjoying the car.
I finally picked up my NSX yesterday from the shop with my new Autorotor installed. The shop doesn't have a dyno, so even though it's supposed to be plug and play, I babied it home until I can get it tested.
Turns out that was a very smart thing to do.
I took it to a DynoJet this morning. Below are the details of the results. My plan is to take it to Autowave on Monday morning if they are free and see if they can find the culprit. In the meantime, I would love some suggestions on what it may be. I've looked at some older threads, and I'm sure that some of you may have had a similar issue before and found the problem.
Attached is the graph of A/F and HP/Torque. You'll see that it stops at just over 5K RPMS. It seems to start OK, then slowly rises until I hit 13 at 5K RPMS, which is when they let off the gas as its too lean. They tried adjusting the Fuel Pressure regulator, but it seemed to have little to no effect.
Any ideas on what may be causing the fuel starvation as the RPMs climb? Keep in mind this is a 92 and many parts have never been replaced. I just had a complete service done - Timing belt and water pump, all seals and gaskets replaced, all hoses replaced, all fluid flushed, and spark plugs changed. The timing belt and water pump was original!
So that tells me that the fuel pump, injectors, anything else that wears over time is very likely an original part and 17 years old. A full leakdown was done and it was at 10%, and that is with the engine cold. This was all checked and done before the Supercharger was installed.
I can only guess that since this is a bolt-on, and assuming it is installed completely correct, there may be something old or malfunctioning that needs to be replaced that is causing this to happen. I am figuring that Autowave is a good place to go since they have a Dyno AND they know the NSX and can find and replace whatever is causing the problem.
In the meantime, any suggestions are appreciated. I will keep this thread updated as the problem is hopefully resolved, and what ends up being the culprit. Hopefully it will be educational for me and anyone else that ever may have this problem.
This is a low boost kit and their gauge showed 6lbs on the dyno. I want to keep the car smog legal and do not want AEM management for now. I don't want to bandaid the problem with an aftermarket ECU that compensates for this problem, but find what part is malfunctioning to cause this. Once it's running properly on a low boost kit, I may consider the upgrade in the future. So I am running lean at only 6lbs, which is low for the Autorotor from what I have read here. They placed the sensor in the tailpipe for the readings. When I picked up the car, the idle was a bit lumpy, but since then it seems the ECU has adjusted and it's pretty solid now. The power curve seems so perfect and smooth, and yet the A/F gets out of hand over 5K.
Mods that may effect what is happening.
Stock airbox
Comptech Headers
Taitec GT Lightweight
Stock Cats
No other power mods
Looking forward to getting it resolved and finally enjoying the car.
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