WHAT HAPPENS when you advance the cams all the way?
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WHAT HAPPENS when you advance the cams all the way?
Originally Posted by Lizard931
I am pretty sure that I am correct on this, though someone else (porken) may correct me.
If you advanced the cams, you will have more bottom end grunt, but if you retard them you get more top end. I also would not go past about 4º either way without other changes being made.
[surfridermason]
I think you have that backwards....Retard moves the power curve to the bottom of the rpm range...BUT LET'S FIND OUT FOR SURE. Does anyone have a quick answer?
I am pretty sure that I am correct on this, though someone else (porken) may correct me.
If you advanced the cams, you will have more bottom end grunt, but if you retard them you get more top end. I also would not go past about 4º either way without other changes being made.
[surfridermason]
I think you have that backwards....Retard moves the power curve to the bottom of the rpm range...BUT LET'S FIND OUT FOR SURE. Does anyone have a quick answer?
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As I understand it...."Advancing and retarding the cam can move the power band up or down a few hundred rpm. Advance for more bottom end and retard for more top end. ..."
#4
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Ok, So Jim and I are on the same page with what the effect of advancing and retarding the cams do.
that is 2-1 so far,
Still waiting for Porken's and/or Louies responce.
that is 2-1 so far,
Still waiting for Porken's and/or Louies responce.
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What MY car? On the 32V you will eventually hit a point (where?) where the valve and piston interfere with each other and cause major damage ala Mong's description.
I believe you are safe at 4º, so all you are likely to accomplish is to shift the power-band up (retard) or down (advanced) int he RPM range. At some point, I would think you will begin to see an effect on overall power, but I'll defer to Ken or Louis.
I believe you are safe at 4º, so all you are likely to accomplish is to shift the power-band up (retard) or down (advanced) int he RPM range. At some point, I would think you will begin to see an effect on overall power, but I'll defer to Ken or Louis.
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It took about 3 degrees crank to make my passenger cam equal my driver cam.
i got a near 5-7hp gain. (1.5 degree cam advance, and about .3mm of valve depression at 20degrees ATDC) Now, both cams are at 2mm at 20degrees
mk
i got a near 5-7hp gain. (1.5 degree cam advance, and about .3mm of valve depression at 20degrees ATDC) Now, both cams are at 2mm at 20degrees
mk
What MY car? On the 32V you will eventually hit a point (where?) where the valve and piston interfere with each other and cause major damage ala Mong's description.
I believe you are safe at 4º, so all you are likely to accomplish is to shift the power-band up (retard) or down (advanced) int he RPM range. At some point, I would think you will begin to see an effect on overall power, but I'll defer to Ken or Louis.
I believe you are safe at 4º, so all you are likely to accomplish is to shift the power-band up (retard) or down (advanced) int he RPM range. At some point, I would think you will begin to see an effect on overall power, but I'll defer to Ken or Louis.
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#8
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Advance lowers the power band giving more grunt low down...........I did my car using Porkens great cam timing tool. Retarding the timing is a little more tricky but still very doable.
#10
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Also i know that Porken has run his cars with upto 8º of adjustment, however iirc he did have some notable pinging in warmer weather with that.
I say 4º is a safe zone to go to, without having to worry about breaking things due to not being fully aware.
I say 4º is a safe zone to go to, without having to worry about breaking things due to not being fully aware.
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Right then I totally goofed,...Now I know what I'm doing tomorrow night if not wed night! LOL
Lizard I owe you one...you just fixed my bass ackwards timing setup...I can't wait to drive the car now!
Lizard I owe you one...you just fixed my bass ackwards timing setup...I can't wait to drive the car now!
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I will set them in the middle best I can, trying to find the original wear marks from the factory....Until I get my paycheck next week....Then I'll get that porken setup....for some precision around here! What's the best way to get at the driver side cam gear without loosening the power steering adjustment block and removing all the belts in the process? Or is that the only easy way to do it properly?
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The timing on the chains was never modified[to my knowledge]. Why can i just use the Porken setup by itself...After all, it uses the offset on the cam gear mounts to find 0 doesn't it? And if the cam sprocket were never moved (internal ones with the chains) I shouldn't have to move them should I? I mean it's not a big deal, and I wouldn't mind learning how to use the gauge, but I'd prefer not to....
#15
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You can use the Porken cam timing tool without removing the cam covers.
The timing is altered by varying the cam position relative to the cam tbelt gear. Look at Ken's site which includes instructions of advancing and retarding cam timing. The cam tbelt gear is bolted to the exhaust cam so varying its timing also varies the intake and overall cam timing through the chain.
It took awhile to figure out how its done just reading the instructions but with tool in hand all becomes apparent...........just keep in mind how a 4 stroke engine works and you'll be fine.
The timing is altered by varying the cam position relative to the cam tbelt gear. Look at Ken's site which includes instructions of advancing and retarding cam timing. The cam tbelt gear is bolted to the exhaust cam so varying its timing also varies the intake and overall cam timing through the chain.
It took awhile to figure out how its done just reading the instructions but with tool in hand all becomes apparent...........just keep in mind how a 4 stroke engine works and you'll be fine.