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Ed Funk
06-24-2009, 12:56 PM
What, other than illegal lift, duration, ramp angles, timing (both in relation to the crank and to the other cam in dual cam motors) could make an engine sound "camey"?

mossaidis
06-24-2009, 01:20 PM
Legally speaking, I would suspect too much porting and a bad tune at idle .... but even then it would only seem a "little camey".

jimmyc
06-24-2009, 01:22 PM
What, other than illegal lift, duration, ramp angles, timing (both in relation to the crank and to the other cam in dual cam motors) could make an engine sound "camey"?

For honda motors with VTEC, several people like to engage the larger cam all the time, this will do it. And because the ECU are open is completely legal.

quadzjr
06-24-2009, 01:31 PM
vacuum leak.

John Herman
06-24-2009, 05:39 PM
A free-flowing, loud exhaust

Knestis
06-24-2009, 06:08 PM
Busted idle stabilizer on a MkII Golf or Jetta will make it "hunt" for idle. Had someone use that as "proof" of a cheater cam in a write up our Production class rally car one time.

K

lateapex911
06-24-2009, 06:22 PM
Ive heard that too. Or just a bad ECU tune at idle, most get to that last when tuning I bet.

On a rotary you might think you hear a cam when it's running rich at low revs. Crane FTW!

CRallo
06-24-2009, 06:49 PM
A cheater cam in a rx7?! Now that is funny! :D

Andy Bettencourt
06-24-2009, 11:21 PM
I am going to go with ECU tune as well. My car has a strange 'zero vacuum' burble that almost sounds like a low RPM rev limiter when I wallow around in the paddock.

Or, sometimes if it looks like a pig, and smells like a pig - it IS A PIG! Cam checks aren't THAT bad!

gran racing
06-25-2009, 07:44 AM
Depends on the car Andy. Suzuki, old Prelude...sourcing one to provide Topeka is gonna be a challenge. A Miata? Easy. Pulling it out from a BMW 2002 and several other similar, head has gotta come off and it's gonna be an expensive protest.

Rabbit07
06-25-2009, 08:48 AM
A car with adjustable timming, i.e. a distributor can sound like it has a cam if the timming is off @ idle. I know I used to disable advance and set timming at 34 degrees in certain IT cars. This would most often be mistaken for a cam. Also makes them hard to start which sounds like you have too much compression.

lateapex911
06-25-2009, 09:08 AM
Also makes them hard to start which sounds like you have too much compression.

Separate starter and ignition switches FTW.

Andy Bettencourt
06-26-2009, 11:51 PM
Depends on the car Andy. Suzuki, old Prelude...sourcing one to provide Topeka is gonna be a challenge. A Miata? Easy. Pulling it out from a BMW 2002 and several other similar, head has gotta come off and it's gonna be an expensive protest.

True Dave. Sounds like there are some rumors about a car or two in Ed's patch. The beauty about a protest - you don't pay if you WIN!

Do your research. Make sure you know your stuff. Protest the car.

Ed Funk
06-27-2009, 08:02 AM
True Dave. Sounds like there are some rumors about a car or two in Ed's patch. The beauty about a protest - you don't pay if you WIN!

Do your research. Make sure you know your stuff. Protest the car.

That's what these threads are, "research".

Andy Bettencourt
06-29-2009, 01:27 AM
Cool. If I can help you find some cam specs, let me know.

Spinnetti
06-29-2009, 07:22 AM
Well, If its a Toyota, when you de-smog it, the idle hunts up and down and idles bad... Especially without the cold start circuit working as it was designed... And that's with stock cams and a stock ecu.

shwah
06-29-2009, 08:56 AM
As noted above - cars that are too rich and/or improperly timed at idle can sound 'cam-ey'

but they also can sound 'cam-ey' when they have a big aftermarket cam...