I was browsing the Touring section and bumped into this thread... https://www.hdforums.com/forum/touri...fuel-moto.html

So far its an interesting read, will be more interested to see what the TW-555 cam does with the bottom end torque. For those who are interested in the specs you can find them here http://www.woodcarbs.com/06-11cams.htm

 

I read the post, now my head hurts.....

 

The main different in the two cams are lift and duration but they don't give the overlap. The intake opening and closing are only a degree difference so with the new lift there should be a bit of a torque gain on the 555's especially in the low to middle R's.

The one degree late closing should have a good effect on puddling and that is a fine line to walk with that high of a lift with just a touch more duration.

Looks like they are trying to find a middle road cam to keep the torque band longer in the RPM's without head work?

 

It looks like you guys may want to reconsider the 6 for the 555. The numbers that they came up with aren't that much more but if you want to replace your cam you may as well use the best one for the job. The 96 isn't that much different than the 103 and it doesn't look like the stock compression will be an issue.

For those using the SEST or TTS a good starting map would be for the 203 cams ( intake opening and closing 18/42- 203 and 21/41-555) then set your CI and VE's to compensate.

 

HuH?........................

 

I'm confused. Are you saying folks should consider the 555 instead of the 6??

 

It's looking like Mr Wood came out with a new grind that is a touch better than the TW6-6. If I already had the 6 I wouldn't change them because the difference between the 2 isn't enough to justify the cost or hassle. If I was looking to buy I'd be leaning heavily towards the 555. Nice this is any changes you or I make will be this winter so there is time to set back and study it a little more before parts are ordered.

 

Didn't Bob Woods originally recommend the 6-6 for the TG? Now my head hurts!

 

What Woods did was to make an improved cam like HD made an improved front belt pulley. Changes like this happen all the time in development.

Woods split the difference between his 5-6 and the 6-6 and called it the 555.

If you remember the Woods conversation reported here... "the 5-6 would be a good cam for the TG 103 but the 6-6 would be a better cam".

Now they developed the 555 and just taking a quick tour of the 555 and the dyno sheets by FM there is just a tweak bit more T & H with the 555 and the T came in just a touch earlier. If you look at his graph you will see the "Harley Dip" (2800 to 3200 RPM's)was smoothed out as well. The "Dip" is where you guys need the extra T.

One thing to remember... this was done on a 96" motor with a PCV on a dyno. Your results will vary. Either cam would be a good cam for the TG owner who wants to pull a heavy load or simply zip around town dressed down.

 

Mr Wizard addressed it very well.