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Loss of HP

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Old Mar 12, 2003 | 10:34 AM
  #21  
L4m3r's Avatar
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From: San Antonio TX
Default Re: Loss of HP

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Silver99LS1:
<strong> </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by CamM:
<strong> Anyway, I was basically told by him this is normal for a street/strip head and that valves seal better when hot. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">That does not sound like something he would say? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">its exactly what was said..... would you care to say what problems you had with yours to this informative thread? <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />
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Old Mar 12, 2003 | 10:36 AM
  #22  
L4m3r's Avatar
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From: San Antonio TX
Default Re: Loss of HP

this was never a bash on this porter..... so why would we make **** up? never once did we use a name..
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Old Mar 12, 2003 | 11:07 AM
  #23  
Jay Johnson's Avatar
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From: north Dallas, Texas
Default Re: Loss of HP

I am the fellow that inspected and flowed Cam's heads.
I won't sugar-coat the information.
the heads were flowed with a clay radiused intake,
and 28inches on an SF-600, same as all of the other
heads that I've flowed.

There were issues with the heads that I considered
to be significant.

1) The surface quality was lacking. Numerous nicks
and gouges visible throughout all intake runners

2) Non-uniform port shape. Each intake runner had
a different shape

3) The exhaust valve was not sealing, light was
seen through the mating surface, it bled 4.5cfm

4) The mating surface was very high up on the intake
and exhaust valve

When I brought the heads back to Cam, I suggested
that he should keep the heads and run them, BUT
after it had a valve job.

I suggested that it would not be a good idea to have
these heads CNC'd. The different intake port shapes
would not be good for a re-cut on with a CNC.
It may produce gaps in the cut due to non-uniform
shape of the port, and a good amount of metal was
taken out in the portwork on the intake.

When Cam told me how much he paid for the heads I
was disappointed for him. It should have come with
a proper valve job with the big valves, and the
surfaces should have been better.

It don't consider the valve sealing issues that I
saw to be acceptible, at any price, for any application.

I've flowed a number of pro-shop heads from sponsors
of this and other web boards. The flow numbers themselves,
were good, even after subtracting the exhaust valve
bleed-off, but the valves needed to be fixed at a minimum.
The surface quality *could* be left as-is.

The heads exhibited low surface quality, a level
that I've not seen at the price level he paid.

Not once did I try to sell Cam into my head porting
services. I simply inspected and flowed the heads.
It's the samething that I would do for anyone else that
simply wanted to get more information on
their heads.

There's other interesting information that I've
aquired from inspecting and flowing the other
board sponsor heads and I've got excellent contact
for information on cylinder heads, but there's no
need to go into that. Cam's heads compared favorably
in flow numbers, but at the bottom of the list in
surface quality and uniformity.

On the upside, Cam reported that he made 410+ rwhp
with these heads.
I suggest that it could improve some with a little
more work on the heads.


Jay Johnson
jayjohnson@rocketmail.com

<small>[ March 12, 2003, 11:10 AM: Message edited by: Jay Johnson ]</small>
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Old Mar 12, 2003 | 11:15 AM
  #24  
Jay Johnson's Avatar
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From: north Dallas, Texas
Default Re: Loss of HP

I would never rely on running the motor to make the
valves seal.

It's simply *not* how it's done.

If a shop put in some big valves, it should have a
valve job done on the setup. At a minimum the shop
could have done an old-school lapping in of the
valves.

I will not divulge the name of the shop where the
heads came from. It's not my issue, I simply did
the inspection and flow services for Cam.


Jay Johnson
jayjohnson@rocketmail.com
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Old Mar 12, 2003 | 11:23 AM
  #25  
CamM's Avatar
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Joined: Jan 2002
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From: Sachse, TX
Default Re: Loss of HP

Thanks, Jay!!
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Old Mar 12, 2003 | 07:06 PM
  #26  
Louis's Avatar
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From: Frisco/Wylie
Default Re: Loss of HP

All things considered, He only picked up 15 rwhp with tuning, and heads! He made 395 before heads, and 408-412 after <img border="0" alt="[judgement]" title="" src="graemlins/gr_judge.gif" />
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