Andrews tw-60 vs. S&S 570's Benefits?

[Mix01FLHT]

Anybody know what the big dif is between the 2 cams?  Is one gonna pull harder at 4000rpm?  Which will run out sooner?  Going into 01 FLHT 95" agressive headwork, 9.8 - 1 compression, SE Flattop pistons, cometic .030 head gasket.

Thanks

[mayor]

the S&S 570's is the better choice of the two based on the rest of your build.  The Tw-60 is waaaaaaaaaaay too much cam for that build. 

[Mix01FLHT]

Bike currently has the tw-60 in it.  what would be the dif?

[mayor]

the tw-60's has a very late intake close that will lower the dynamic compression (the compression created after the intake is closed and compression is being built), plus the tw-60's have a very long duration in the 95" engine size.  I would guess the tw-60's would be very soft at 9.8:1 compression (assuming that is static).  The S&S570 are a very good cam at 9.8:1 static compression. 

TW-60 duration 260/260; .560" lift ; intake close 56 degrees
S&S570 duration 240/255; .570" lift ; intake close 40 degrees

[Mix01FLHT]

added torque?  added Hp?

[mayor]

torque earlier, and probably more than you have now since your corrected compression should be fairly low with the tw-60's at 9.8:1 static.  My guess is your hp numbers go up too, since you don't have the supporting cast for the 60's. 

[Mix01FLHT]

bike currently 102lbsTorque 100hp.

[mayor]

got a chart?  is there a big dip before 3,500?

[Mix01FLHT]

can't find the chart, but yes dip was I thought from thunderheader.  changed to true duals with thundercones. 

[LilEvilAmy]

TW60's will definitely need more compression than 9.8:1, so the 570's would be better matched to your build.
Here is a fairly good comparison - both 95" with head work, 2:1 exhaust, and 44mm CV carb.
Of course, YMMV. 


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[Mix01FLHT]

TW60's will definitely need more compression than 9.8:1, so the 570's would be better matched to your build.
Here is a fairly good comparison - both 95" with head work, 2:1 exhaust, and 44mm CV carb.
Of course, YMMV. 

What is the compression on these 2 bikes?  If they are the same, I would go with the Andrews 60's.

[LilEvilAmy]

IIRC, the 570 build is around 9.8:1, and the TW60 build is around 10.8:1 (+/-)

[Mix01FLHT]

The TW60 chart looks more like my current chart except for the dip mine has at the beggining from the thunderheader.  So it looks like I would be going backwards to the 570's.

[mayor]

The TW60 chart looks more like my current chart except for the dip mine has at the beggining from the thunderheader.  So it looks like I would be going backwards to the 570's.

backward in what way?  If all you want is peak numbers, stay with the cams you have and up the compression to about 10.8:1.  If you want something that feels stronger on the street switch to the 570's. 

[Mix01FLHT]

most of my riding is done on the freeway at between 3500 and 5500rpm.  when these guys decide to go its at 4000rpm and up.  Stop light to stop light is of no concern to me.  I average 12000 miles a year and 85% of that is freeway.

[Mix01FLHT]

anybody ever heard of these cams "Carl's Speed Shop CM600G"?  Anybody know anything about them?

[bigblock6912]

carl doesn't part with any numbers except duration and top dead center lift. kind of hard to plot his cams

[bigblock6912]

and the .600 lift