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 Post subject: Engine question???
PostPosted: Sat Feb 25, 2012 12:22 am 
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Joined: Fri Nov 07, 2008 8:49 am
Posts: 244
Location: sw pa
Y does my engine turn the intake runners black like exhaust ????? valves and timing r set right it only sees 110 fuel and gets air threw a k&n filter . runs strong so y the dark haze in the runners ???


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 Post subject: Re: Engine question???
PostPosted: Sat Feb 25, 2012 12:45 am 
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Joined: Sat Feb 24, 2007 12:02 am
Posts: 349
Location: Germantown Ohio
Its caused by the overlap in the cam. This is when both intake and exhaust valves are open at the same time. Could also be caused by valves that aren't sealing up very well.


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 Post subject: Re: Engine question???
PostPosted: Sat Feb 25, 2012 12:58 pm 
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Joined: Fri Nov 07, 2008 8:49 am
Posts: 244
Location: sw pa
Thanks Aaron i thought thats what it was but just wanted to check


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 Post subject: Re: Engine question???
PostPosted: Sat Feb 25, 2012 1:48 pm 
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Joined: Wed Dec 17, 2008 5:56 pm
Posts: 783
Location: mooers hill IN
X2 Could be the Cam is to big for the RPM you run in most of the time . Are you happy with RPM TQ and hp of eng ? OR spring or valvae job .


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 Post subject: Re: Engine question???
PostPosted: Sat Feb 25, 2012 2:44 pm 
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Joined: Fri Nov 07, 2008 8:49 am
Posts: 244
Location: sw pa
i like the power of engine it has decent bottom strong mid to upper cam is .546 lift with 1.4 rockers 298 duration 262 at 50 daul scat springs street elimanator heads 11.3 compression 1 5/8 exhaust ive got it tore apart because of a barrel leak and noticed this hazing i have a heavy right foot and like the engine. maybe this is a bad combo but i havent really had any professional vw builder advice i have built a few vw engines and numerous v8 engines i just used a general engine knowledge to come up with this combo !! let me know what u think thanks oh yea its a 2387


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 Post subject: Re: Engine question???
PostPosted: Sun Feb 26, 2012 12:00 pm 
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Joined: Wed Dec 17, 2008 5:56 pm
Posts: 783
Location: mooers hill IN
Looks good to me !! Idleing around in the woods at low RPMS did it. But if its down cheek springs. I try to put spring on every 2 years if i been runing it hard . ? what cam is that c45?


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 Post subject: Re: Engine question???
PostPosted: Sun Feb 26, 2012 12:48 pm 
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Joined: Sat Oct 17, 2009 10:01 am
Posts: 321
Location: Butler, PA
I was of the understanding that increasing valve duration and also overlap in cam timing was to increase the scavening effect at higher engine rpm.This leads to reversion of the air flow at lower speed which is why you notice the stain at the bottom of the intake.( Also there is a standoff mist created at the carb with long duration cams which can be contained with the use of a velocity stack type air filter.)


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 Post subject: Re: Engine question???
PostPosted: Sun Feb 26, 2012 7:19 pm 
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Joined: Wed Dec 17, 2008 5:56 pm
Posts: 783
Location: mooers hill IN
Aaron Creech wrote:
Its caused by the overlap in the cam. This is when both intake and exhaust valves are open at the same time. Could also be caused by valves that aren't sealing up very well.


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 Post subject: Re: Engine question???
PostPosted: Sun Feb 26, 2012 7:20 pm 
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Joined: Wed Dec 17, 2008 5:56 pm
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Location: mooers hill IN
hyde wrote:
X2 Could be the Cam is to big for the RPM you run in most of the time . Are you happy with RPM TQ and hp of eng ? OR spring or valvae job .


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 Post subject: Re: Engine question???
PostPosted: Sun Feb 26, 2012 7:22 pm 
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Joined: Wed Dec 17, 2008 5:56 pm
Posts: 783
Location: mooers hill IN
Bubbalowe wrote:
I was of the understanding that increasing valve duration and also overlap in cam timing was to increase the scavening effect at higher engine rpm.This leads to reversion of the air flow at lower speed which is why you notice the stain at the bottom of the intake.( Also there is a standoff mist created at the carb with long duration cams which can be contained with the use of a velocity stack type air filter.)

Yes you are right .


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 Post subject: Re: Engine question???
PostPosted: Sun Feb 26, 2012 8:18 pm 
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Joined: Fri Nov 07, 2008 8:49 am
Posts: 244
Location: sw pa
yes Hyde its a c45 have u used these cams before??? if so where did the power fall off this engine falls off power at about 6000 is that what to expected thanks


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 Post subject: Re: Engine question???
PostPosted: Mon Feb 27, 2012 9:21 pm 
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Joined: Wed Dec 17, 2008 5:56 pm
Posts: 783
Location: mooers hill IN
No i have not used a c45 .I have a fk 44 in 2387 peck HP 5600 but pulls hard to 6000 0n the dyno. A c45 should pull hard to 6000. Are the heads ported and what carbs ?


Last edited by hyde on Tue Feb 28, 2012 8:36 pm, edited 1 time in total.

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 Post subject: Re: Engine question???
PostPosted: Mon Feb 27, 2012 10:47 pm 
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Joined: Fri Nov 07, 2008 8:49 am
Posts: 244
Location: sw pa
yes heads r ported carb is a different deal im running a holley 500 cfm 2 barrel carb and custom intake but i think the intake is choking it on top end im looking to redesign the intake next week well see how it works at the wellsville hill climb i am not a big fan of dual carbs they just seem to be a pain unless u spend a bunch of money on them ( too many jets to clog ) also we r getting ready to do some dyno tests with dual carbs and holley stuff to see how the compare who knows lol


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 Post subject: Re: Engine question???
PostPosted: Wed Feb 29, 2012 9:08 pm 
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Joined: Wed Dec 17, 2008 5:56 pm
Posts: 783
Location: mooers hill IN
Keep me posted


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