Porting for Torque

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Dec 25, 2008 | 11:11 AM

tbrenan

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Road Captain

Joined: Jul 2006

Posts: 658

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From: Aldergrove BC, Canada

Porting for Torque

I have looked at most of the online head porters and all seem to be centered on Horse Power and I am not, a top speed type of rider but more of at or slightly above the speed limit type of rider

BUT! I do like the instant response that torque gives ---should the need arise.

I have an 07 FXD and have no intention ( at this time) of changing cams.

I always built my car motors for torque, but am slightly confused about how to go about getting hi torque numbers by just porting the heads, more flo ----seems to equate to more cam

Insights, tips, hints greatly appreciated.

Dec 25, 2008 | 11:17 AM

Mascman

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Joined: Apr 2006

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From: Clarksburg, PA

You say you don't want to change the cams, but IMO, that would be the first change I'd make for more torque. Everything I've had ported was always improved on the top end.

Sounds like you may be looking for the Andrew's power pulley for a little more off the line.

I've heard that my 2006 is geared a little lower than the '07 and ups...maybe you can get a 2006 pulley.

Dec 25, 2008 | 11:43 AM

paul s

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Joined: May 2008

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From: la

https://www.hdforums.com/forum/dyna-...n-07-dyna.html Pulleys will move your powerband where you want it, a mild port job will help also. Big ports and big valves kill lowend power but makeup for it in the mid and topend.

Last edited by paul s; Dec 25, 2008 at 11:47 AM.

Dec 25, 2008 | 11:48 AM

Mr. Lucky

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Joined: Mar 2008

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From: Delaware

Quote:

Originally Posted by Mascman

Everything I've had ported was always improved on the top end.

Yes, porting (or preferably, porting and polishing) involves removing material. Less material = larger chamber, which = lower compression ratio, which = less low end. Porting is intended to match the intake/exhaust requirements of the cam to the combustion chamber and to smooth the flow.

If you are looking to improve torque, look elsewhere. Bigger cubes, milled heads, and higher gearing (numerically) would all be good choices.

Dec 25, 2008 | 12:07 PM

rounder

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Joined: Oct 2007

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From: Palm Harbor fl.

Also what exhaust system are you running... A D&D fatcat, or supertrap 2-1(tuned for torque) can do wonders for providing a stronger torque curve...

Dec 25, 2008 | 12:53 PM

dyna rider

Club Member

Joined: Dec 2007

Posts: 4,192

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From: Knoxville, Tn

Torque

I had S.E. 211 cams in my bike with stock heads and the low end torque was great from 2G all the way to 5.5g. They added 20-30 ft pds to the stock numbers. I also had HC pistons installed. I know you don't want to change cams but it will make a dramatic difference.

Dec 25, 2008 | 02:07 PM