You can set it to '0' if you prefer and adjust your intake cam ranging from +2 to -4 or so depending on what you want. Actually, that's easier as it only requires one adjustable cam gear.

 

retarding the exhaust cam will move your exhaust cylinder head efficiency up in the rpm range. as the exhaust valves shut later you breath better at higher rpms but there is of course the disadvantage that at lower rpm if they shut too late you lose some air.

 

That's what i'm doing this weekend, i'm only using one cam gear for my 280 settings (+2/0).

 

That will idle like crap, but you should have great top-end. Do you really want more overlap with 280s? Isn't there plenty of overlap even at 0, 0?


Eric

 

Actually, it idles rough but gives a fat midrange and quick spool. If you want best possible top end, you'd leave the exhaust cam alone and retard the intake cam to -3 or -4.

 

Sorry, I wasn't thinking right when I made the comment about the top-end. I was just think about the increased overlap and bad idle. I know that retarding the cams and reducing overlap increase top-end and advancing the intake to create more overlap will help with spool and midrange.

Eric

 

So would I benefit more from the +2/0 setting or the -3, -4 setting? I'm going for which ever gives the most power for drag racing.

 

If you're going drag racing, you don't care as much about midrange torque and spool characteristics - things that you'd want for street antics.

For drag racing, you'd want to use something like -3/0 or maybe even -4/0.

 

Well i'm going to drive the car on the street everyday but the main purpose of the car is drag racing, would the -3/0 or -4/0 cause slow spool or anything like that? I know you said you gained a good amount of mid-range TQ with the +2/0 setting and some HP as well, what would the other settings add? Just more power up top?

 

Yes

Yes, less midrange and more power up top.

 

I'll just stick with the +2/0 setting

 

Ted B, what's your take on cam timing as ambient temperature increase? Would you run the same cam timing in 45 degree weather as you would in 90 degree weather? Would you run less advance on the exhaust cam to deter detonation in warmer weather?

 

I currently have comp 272s and a 50 trim kit. IF I added cam gears any idea how much i could possibly pick up? What would be a good setting for the street and then for top end... Does adjusting the cam gears effect the tune?

 

When dyno'ing (on stock turbo) changing the cam gears didn't change my tune much if any. As for how much you might pick up..... all CGs do is move the powerband around.... So if you want more low end you give up some top end. With CGs at -2/-2 I picked up about 10WHP of midrange and gave up about 10WHP top end. I imagine with a bigger turbo those number would be bigger as well.

 

For that particular set, I'd use +1/-1.