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Author Topic: priority in the build - porting or cam first  (Read 2305 times)

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Offline TheJawsOfDeath

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priority in the build - porting or cam first
« on: February 28, 2012, 06:01:43 PM »
Excuse me if this has been covered, but I couldn't really find an answer after searching for a bit. I'm at a crossroads on the rebuild of my 750 K8's engine.  I can afford either a high perf cam, or having the head ported by mike on the boards here, not both.  The porting job is going to be about twice as much as a cam.  Engine is going to be otherwise rebuilt with stock bore.  My build is budget minded, i.e. I'd be using a cam that will work with stock springs.  What's the best bang for my buck for the money? 
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Offline cougar

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Re: priority in the build - porting or cam first
« Reply #1 on: February 28, 2012, 06:28:05 PM »
Hey Jaws ; This is just my opinion but I would say do the port first. Granted the cam is cheaper and will put (probably more) performance in your motor Now. But I look at it in the long run, giving the motor the ability to breath will help now and when you cam it. And besides if you get the port job now then with just a little coin you can drop in a cam! Like I said this is just mt opinion  ;D . I'm sure you'll get more opinions, just give it a little time .   ...cougar...
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Offline kpier883

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Re: priority in the build - porting or cam first
« Reply #2 on: February 28, 2012, 08:06:18 PM »
There is a thread around somewhere in which a stok bike is ported without other changes.  Results were good.  I'll try to find it.
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Offline Retro Rocket

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Re: priority in the build - porting or cam first
« Reply #3 on: February 28, 2012, 08:13:28 PM »
Port it first, porting these heads give the single biggest gain in performance than any other mod. Check the forum for a cheap cam, should be one here somewhere.... ;)
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Offline kpier883

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Re: priority in the build - porting or cam first
« Reply #4 on: February 28, 2012, 08:15:58 PM »
Quote from: kpier883 on February 28, 2012, 08:06:18 PM
There is a thread around somewhere in which a stok bike is ported without other changes.  Results were good.  I'll try to find it.
Found it:
http://forums.sohc4.net/index.php?topic=40311.msg415347#msg415347
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Offline TheJawsOfDeath

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Re: priority in the build - porting or cam first
« Reply #5 on: February 28, 2012, 08:19:05 PM »
THAT'S the post! Thanks.  I just couldn't find it for some reason.
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Offline TheJawsOfDeath

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Re: priority in the build - porting or cam first
« Reply #6 on: February 28, 2012, 08:29:38 PM »
...hmm...seems I'm getting ported first.
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Offline kpier883

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Re: priority in the build - porting or cam first
« Reply #7 on: February 28, 2012, 08:57:51 PM »
I think that is a good choice.  I hope to do the same some day.  A guy can dream, right?
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Offline BLUE71TURBO

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Re: priority in the build - porting or cam first
« Reply #8 on: February 28, 2012, 10:51:52 PM »
Since your going to have the head off to do port work and a valve job you should really install new better valve springs not that much more $$ .    ;)
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Offline dragracer

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Re: priority in the build - porting or cam first
« Reply #9 on: February 29, 2012, 09:22:55 AM »
Quote from: BLUE71TURBO on February 28, 2012, 10:51:52 PM
Since your going to have the head off to do port work and a valve job you should really install new better valve springs not that much more $$ .    ;)

What he said!!!
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Offline Bill/BentON Racing

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Re: priority in the build - porting or cam first
« Reply #10 on: February 29, 2012, 06:23:40 PM »
+1.Valve springs cheap insurance...don't risk that head! Bill
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: priority in the build - porting or cam first
« Reply #11 on: February 29, 2012, 06:41:39 PM »
Valve springs are good insurance against valve float when you miss that 1 - 2 power shift as I did. Total destruction ensued.

Now with that being said the 78 K already uses the stronger springs found in the 77 & 78 F. I'm sure Mike will fit you with even stronger KPM springs while he's at it.
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