Cam advance - increased FE?

[Rower4VT]

My Acura is a SOHC 5-cylinder. I'm guessing that if I advance the cam 1 tooth it'll be about a 8-10 degree advance.

Has anyone advanced the cam on their engine? About how many degrees of advance? What kind of increased FE did you get out of just advancing the cam? Thanks for any help!

[GasSavers_Erik]

I heard that 1 cam tooth on Hondas is actually 18 degrees on the crankshaft- because 8-10 degrees rotation of the cam is twice as much in relation to the crank.

[tweakmenow]

I have a 97 Honda Delsol SI with a D16Y8. I advanced the camshaft 5 deg, by machining the keyway slot and using a fatter key. BIG increase in lowend torque. I can now go up hills in 5th gear, that previously was only possible in 4th. Vehicle is Scanguage equipped. Mileage increased about 10%.
Advanving the cam one gear tooth will be 18 deg. WAY too much....

[Rower4VT]

Good to know. I didn't even think about the fact that the crank will be going around twice as many degrees as the cam. How did you determine how much to maching the slot?

My (non-adjustable) distributor is on the back end of the cam shaft. So increasing cam timing will advance the rotation of the distributor also. The Vigor has electronically set ignition timing. Do you think I'll have to find a way to "reset" the distributor, or do you think the ECU will adjust the timing back to within specs? Thanks for the input.

[GasSavers_bobski]

Don't machine the keyway unless you're really hurting for cash - get an aftermarket adjustable cam gear. That way you can adjust to your hearts content, or go back to stock if you so desire.

As for the ignition timing, if the Vigor is set up the same way as older Legends, there's a potentiometer in the emissions black box that can be turned to adjust the timing.

[Rower4VT]

Yup, figured out the timing thing. The distributor is fixed, but there is an adjustable potentiometer like you said.

No adjustable cam gears available for a Vigor (or 2.5TL, same engine). Instead of filing the cam gear keyway slot, I'm going to use an offset key. That way I can change the timing and go back to stock if need be.

Tweak, Just to clarify what you wrote, you advanced the cam itself 5 degrees which is 10 degrees of advance compared to the crank angle. Right? Do you have your ignition advanced also? If so, by how much? Thanks!

[tweakmenow]

Yes, I advanced the camshaft an actual 5 degrees. An offset key is perfect for the job...

As far as ignition timing goes, I shorted out the plug inside the passenger compartment with a paper clip, and advanced the timing just 2 deg. When I put the car back on the road this Spring, I am going for two more deg. (plus 4 total over stock)