w cams can you tell me about them

[shotgun46]

I have a 1998 S and I am told it has W cams and dual plugged heads what does this do for proformance and how are these cams different

[aswracing]

"W" cams have the intake timing pulled way back from the standard "D" cams, in other words it opens the intake valve sooner and it closes it sooner. Closing it sooner builds more cylinder pressure.

On top of that, the "S" heads on your bike, also known as "Lightning" heads, have smaller combustion chambers than the standard 1200 hemi heads of that era; as such, the bike has more compression.

The idea of the dual plugging was to allow this combination, i.e. the early close timing of the "W" cams together with the higher compression from the "S" heads, to work without causing detonation. Dual plugs result in a faster burn that can be initiated later, and it tends to reduce detonation better.

On the intake open side, the "W" cams have more "overlap", which basically means there's a larger window of time at the tail end of the exhaust stroke and the front end of the intake stroke where both valves are open. Overlap basically connects the intake to the exhaust, and therefore gives the pipe more control of the cylinder fill. It essentially gives the pipe more control over the powerband, and makes it's selection that much more critical.

[shotgun46]

Thank you ! now I have a better understanding of what I have ! I am a Drag Pipe nut but have removed them and went with a stock exhaust system with SEIIs mufflers the bike seems to have more torque down low and my butt dyno says it's more throttle responsive in the mid range ! and 1 other Question with this motor does it have the same HP / Torque ratings as all the other 1200 motors ???

[aswracing]

There are lots of 1200S owners on the site who can probably answer that question definitively, but to my aging memory, I seem to recall Harley not making any horsepower claims back then, but claiming the 1200S made more torque than the standard 1200. Hopefully a 1200S expert will chime in soon.

But of course, horsepower is torque times rpm, which means that at any given rpm, more torque means more power.

[shotgun46]

Thank you ! I appreciate your help and answers !

[steelworker]

Click here for a link to an early review of the '98 1200S.

Basically, with the engine mods you get little difference until Harley taxes are paid, after which you can expect a bit more grunt than you'd get from other models from that era.

As Aaron mentioned, it's not surprising that you're getting better results with SE slip-ons than with drag pipes.

[shotgun46]

Originally Posted by steelworker

Click here for a link to an early review of the '98 1200S.

Basically, with the engine mods you get little difference until Harley taxes are paid, after which you can expect a bit more grunt than you'd get from other models from that era.

As Aaron mentioned, it's not surprising that you're getting better results with SE slip-ons than with drag pipes.

thank you for the info and the link ! sooner or later I am going to change the air box and re jet the carb ! and I do love the low rumble of the new exhaust

[madnss]

A good aftermarket air cleaner would help out a lot with your slip ons. Another cheap idea would be to put a 27 tooth front pulley on instead of the 29. 27 would be 883 factory pulley. It would gear the bike down a touch. Just a thought. Good luck

[shotgun46]

Originally Posted by madnss

A good aftermarket air cleaner would help out a lot with your slip ons. Another cheap idea would be to put a 27 tooth front pulley on instead of the 29. 27 would be 883 factory pulley. It would gear the bike down a touch. Just a thought. Good luck

thanks ! but I don't think I am going to change the pulley just the air box ! I am not in a hurry to go fast any more ! now to find a good air box I think I will go with the ness big sucker depending on the price

[Gcram399]

Are you running a stock air cleaner inside the stock box? If so, I might be able to help.