I would be carefull with the generalization that they are all retarded. My problem is exactly the opposite, after richening it up a bunch (12.5) I still can't get rid of my detonation. I'm running the K&N aircleaner in the stock housing with Fullsac true duals into 1.75 Wildpigs and when it gets hot it detonates. So I will be using the new setup to retard mine. I'm running the 393 map which runs great except for the detonation. Ride the **** outa them...........Charlie

 

Can you isolate your detonation down to an RPM range and load? If that's the case, you can likely increase the timing in certain areas such as lower RPMs and retard the timing in the RPM range at the throttle position that causes the detonation. Dropping the timing on a more agressive slope at an earlier throttle position will likely address the problem since it appears that you already have plenty of fuel being injected.

 

[sm=popcorn.gif]

 

I havn't had a chance to play with the new timing pages yet, they will more than likely solve my problem. All the cruise range timing is advanced a bit to far in TPS position. When cruising at 70 on cruise control and hit a grade, its like somebody flips a switch and it starts detonating. So I will work on backing the timing ramp to a lower TP and retard the base of the ramp a little more. Once the detonation is gone I will then refine the advance and then lean my fuel pages to get my mileage back. It runs better each day but the timing apparently can't be learned but at least now we have a way to adjust it.

 

I'd like a link to the DTT timing's you used and I'm wondering if these timings are based on TPS or MAP(kPa). Also, how were you able to discern what timing numbers to use off the DTT tables for the TMax since the TMaxuses TPS, and how you where able to tell if you weren't potentially predisposing your engine to possible damage for the lack of being able to time the front and rear cylinders since I see no where in the TMax program to allow this since it appears TPS vs. RPM vice RPM/MAPof Speed Density tuners.

 

I translated the timing settings from the 2007_96CID base map in the DTT PC Link software. DTT uses manifold pressure (in-Hg). I assumed the lowest pressure, 16 in-Hg, is equal to 0 TPS and the higher pressures would be TPS of load. Not just WOT, but a twist of the throttle during a cruise. This, as I understand it, is how the manifold pressure settings could be translated to throttle position.

I've been getting better performance and little to no detonation. What I did experience I was able to tune out with a simple change. I can't tell of any damage. Who's to say the stock settings won't have long term effects on the engine?

Here is a link to the suggested DTT timing map...

http://www.head-quarters.com/html/efi_i_tuning.html

And, here is a graphic from the DTT PC Link software. Hope this helps...



[IMG]local://upfiles/27862/024BDABD47604A1BB44AE927F11160DC.jpg[/IMG]

 

Let's be sure we are not confusing things here.....

Both TMax and DTT are Alpha-N devices.

The terms "Alpha-N" and "Speed Density" apply to fuel management / control systems.

Timing contorl has nothing to do with Alpha-N or speed Density. Timing is timing.

TMax and DTT use different methods for timing management. TMax uses a the relationship between RPM & TPS (I believe), where DTT uses the relationship between RPM & Manifold Absolute Pressure (vacum).

 

Dang was any of this in English?

 

One reason why I asked for a link so I could see how the DTT listed timings.

What I do have a problem understanding is how you can apply timings based onRPM and TPS(Tmax) to those that are based on RPM and MAP which again, I "thought" this would be a Speed Density device according to this exerpt here:


We will limit our discussion to the types of fuel injection systems that are likely to be encountered on motorcycles. One of the major differences between fuel injection systems is how the sense the amount of load that is placed on the engine. The load can be sensed by how far the rider has twisted the throttle and MAP (manifold absolute pressure). EFI systems that sense engine load by the use of the throttle or TPS (throttle position sensor) are referred to as an Alpha-N system. EFI systems that sense engine load by the use of a MAP sensor are referred to as a Speed-Density system. Harley-Davidson has used both types of EFI systems on its vehicles. While many of the sensors can be the same in both types of EFI systems, there is a significant difference in the way that each system determines what the load on the engine actually is. The Magneti-Marelli system used on EVO and Twin Cam FLH's until 2001 and Buell XL engines is an Alpha-N EFI system. On these bikes, load sensing is determined by the throttle position. The newer Delphi EFI system used on current Twin Cam engines is a Speed Density system. Speed Density EFI systems determine the engine load based on the intake manifold vacuum.

Found here: http://www.nightrider.com/biketech/m...efi_basics.htm

 

LOL. I hear ya. I can understand part of it. I'm no expert, so don't that anything I say as an expert opinion. All I know is what I'm able to figure out from research and reading what others have done - here and on other forums. I took a chance believing the timing was off and advanced it. As I went up in the timing, I became more and more convinced I was moving in the right direction. I'm happy where the bike is at now. Any further tweeks will be minimal, I hope.

I'm definately not saying that what I've done is right and don't want to be seen as defending anything. If anybody has any suggestions, recommendations, complaints, or arguements please post them. I hope to improve our use of this device and share our experiences with all of those that participate in this forum.