SE-204 Cam and dyno

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Jun 12, 2010 | 05:31 PM

#41

Mike

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From: Centralia, Wa

Quote:

Originally Posted by fripple

It's still running strong and I'm glad I chose the SE-204.

I still want more power so maybe a 103 or S&S 106 kit might be coming soon

If you go 103 or 106, you can use the SE high ratio rockers to gain a little more tq across the band. (gives the 204 an effective lift of .539)

Jun 12, 2010 | 05:59 PM

#42

fripple

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From: down south

Yeah I thought about that too. Probably do the heads while I'm at it. I'd like to see how much I can squeeze out of these 204's.

Jun 13, 2010 | 09:00 AM

#43

troop

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From: Stoughton, WI

Quote:

Originally Posted by boogaloodude

If you go 103 or 106, you can use the SE high ratio rockers to gain a little more tq across the band. (gives the 204 an effective lift of .539)

What are the pros/cons of going with high ratio rockers? And then, could you safely use the $175 SE Pro Rocker 1.75 ratio arms or would you need to spend the $400+ on the SE Roller Rocker arms ? Big difference between the $300 cost/performance benefits ??

Last edited by troop; Jun 13, 2010 at 09:17 AM.

Jun 13, 2010 | 10:56 PM

#44

Mike

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From: Centralia, Wa

Quote:

Originally Posted by troop

First off, let me say that I didn't figure out that I could use the high ratio rockers, it was a recommendation by a couple of builders who are much smarter than I am.

The pros are, it increases lift just a little, which should help cylinder fill. The downsides are... if you've added too much lift, it can slow down the intake charge, which will hurt performance.

You want just enough of a valve opening to keep the charge moving as fast as possible, and enough of an opening to allow as much fuel in as the motor needs. Not enough, and you're losing power by not allowing enough fuel. Too much, and you lose power by slowing the intake charge, actually reducing the amount of fuel that goes into the combustion chamber.

I went with the non roller rockers. At the modest lift we're talking here, roller rockers aren't really called for. If you're running big lift cams, and high rpm motors, then roller rockers can help valvetrain lifespan and efficiency.

Jun 14, 2010 | 06:12 AM

#45

troop

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From: Stoughton, WI

Does it shift the TQ curve or just add more to it? You and Stoood might have me thinking of adding these to the build. Dang !!!

Jun 14, 2010 | 07:55 AM

#46

fripple

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From: down south

Quote:

Originally Posted by troop

Does it shift the TQ curve or just add more to it? You and Stoood might have me thinking of adding these to the build. Dang !!!

Add them if you have the extra funds. What are the specs of your build?

Jun 14, 2010 | 07:40 PM

#47

troop

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From: Stoughton, WI

Quote:

Originally Posted by fripple

Add them if you have the extra funds. What are the specs of your build?

My build will consist of 103" SE flat top pistons (stock cylinders bored), heads street ported, 204 cams and using stock .045 thickness head gaskets. I ride solo 95+% of the time. Is their other additional cost other than the $140 (after 20% off) for the SE 1.75" rocker arms? I would advise the head porter of this. Additional torque would be nice but just wondering of any vices with the rockers? Troop

Jun 14, 2010 | 07:56 PM

#48

Mike

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From: Centralia, Wa

Quote:

Originally Posted by troop

Does it shift the TQ curve or just add more to it? You and Stoood might have me thinking of adding these to the build. Dang !!!

They should not shift the torque curve at all. I was told they should be good for an additional 3-5 ft/lbs across most of the torque curve in my bike. Since I had the rocker boxes off, it seemed like a cheap way to add a bit of torque