Author Topic: The Value Of Head Porting, Test on 95" motor  (Read 1765 times)

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Offline HD Street Performance

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The Value Of Head Porting, Test on 95" motor
« on: July 09, 2015, 03:18:10 PM »
This test was done as close to optimum, back to back both builds tuned on the same dyno during similar weather conditions. Purpose was to show a tuned 95" motor with the heads only changed and the same compression maintained.
The build is an 06 95" with 203 cams and Rinehart exhaust SE air cleaner. The graph is before and after. The head porting was an intake valve changed to 1.9" exhaust remained stock size
Result gain 8hp 5tq with no loss of low end torque, actually torque increased across the board, as measure at WOT for the dyno test.

Offline joe_lyons

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Re: The Value Of Head Porting, Test on 95" motor
« Reply #1 on: July 09, 2015, 06:35:13 PM »
Can't beat that.
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Offline sfmichael

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Re: The Value Of Head Porting, Test on 95" motor
« Reply #2 on: July 26, 2015, 07:19:07 PM »
great info - thanks Don  :up: :up:
Colorado Springs, CO.

Offline bensfatboy

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Re: The Value Of Head Porting, Test on 95" motor
« Reply #3 on: November 28, 2015, 07:39:51 PM »
This test was done as close to optimum, back to back both builds tuned on the same dyno during similar weather conditions. Purpose was to show a tuned 95" motor with the heads only changed and the same compression maintained.
The build is an 06 95" with 203 cams and Rinehart exhaust SE air cleaner. The graph is before and after. The head porting was an intake valve changed to 1.9" exhaust remained stock size
Result gain 8hp 5tq with no loss of low end torque, actually torque increased across the board, as measure at WOT for the dyno test.


Dang Don, now you really got me confused.  With this post using basically everything stock you get 8 and 5. On a later post you get 21 plus the whatever tq with a very minute change in the bore.  What is the real deal for just porting the heads on a stock 103 TC with cams and hi flo ac?

Offline HD Street Performance

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Re: The Value Of Head Porting, Test on 95" motor
« Reply #4 on: November 30, 2015, 05:22:46 AM »
The key is the tune. If both are optimized the heads typically produce 7-10 hp and 5 torque assuming all the same components are in place on these mild builds. The other post was a stock stage 1 motor with stock cams. Neither before or after we're optimized tunes. So I am not trying to say those results can be duplicated. Just in that case the hp went up that much. But I provided the details so no trickery was involved. The event underscores the importance of a quality tune with a flash based tuner such as the power vision or TTS or direct link.
We will have more reliable results when Jim puts the ported heads on his 96" stocker. That said a 103 may have a stronger result because the larger motor has a higher airflow demand.