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CVO Technical => Twin Cam => Topic started by: nampatown on November 02, 2022, 10:18:52 PM

Title: Cam choice for no detonation
Post by: nampatown on November 02, 2022, 10:18:52 PM
Hello all.
I have a 2009 ultra. Was a 96 ci. I installed a stage 4 engine kit.  103 ci. 58mm TB.  259e cams. 
My local HD shop did dyno and there is detonation.   I took it back to that hd shop and they fattened up the fuel and it still detonates.  And plugs are fouling.   
I gave up on my local HD shop and purchased a thundermax tuner.   After many hours of tuning I still have some detonation at mid to upper rpm range.   Don’t dare put weight on the back seat.   
My question is : is there a cam I can install to replace the 259e cam that will bring power in sooner to eliminate the detonation???
PLEASE will someone with experience in this area chime in.   
I haven’t rode it in 2 summers. 
Title: Re: Cam choice for no detonation
Post by: trippy on November 03, 2022, 01:36:00 PM
If you have a Tmax ECU, I would go to them, explain whats happening, they have good Customer service, they will  ask you to upload a data file from your Tmax and then tell you how to adjust the timing to elliminate the Pinging. Good luck.
Title: Re: Cam choice for no detonation
Post by: HD Street Performance on November 05, 2022, 11:35:08 AM
Welcome to this forum.
Consider the build never broke in properly, and there is oil in the combustion. The tune may have contributed to the demise.
It needs to come apart to find the source of the plugs that are oil-fouled.
Excessive oil consumption has the effect of lowering the octane of the fuel.
Title: Re: Cam choice for no detonation
Post by: Twolanerider on November 05, 2022, 11:59:27 AM
For a long time in the original Twin Cam versions Thundermax did not utilize the ion sensing ability of the ignition system so effectively had no spark knock sensing ability (even when the bike did/could have).  I don't know on the newer versions of their module but does anyone know if later versions of Thundermax brought any kind of knock sensing back in to their system?
Title: Re: Cam choice for no detonation
Post by: HD Street Performance on November 05, 2022, 01:05:59 PM
The Tmax changes the timing scheme from MAP based to throttle position and eliminates all knock controls. It does have a heat VS timing table, however. Very crude compared to the OEM Delphi.
Title: Re: Cam choice for no detonation
Post by: Twolanerider on November 05, 2022, 05:22:15 PM
Quote from: HD Street Performance on November 05, 2022, 01:05:59 PM
The Tmax changes the timing scheme from MAP based to throttle position and eliminates all knock controls. It does have a heat VS timing table, however. Very crude compared to the OEM Delphi.

Not surprised and thanks for the confirmation.  Never a fan.