Adjustable Cam Gears
 

I just installed a set of Fidanza cam gears on my NA8. I was curious about far I could advance them without damaging things, because i'm running a Mazda speed intake cam I would assume that I could not advance it as far. Compared to a stock cam. BTW

Until it knocks or stops making more power. Whichever comes first. Just watch your logs really closely.

Why are you trying to move the powerband towards the lower RPM range?

Be careful not to create too much overlap between the exhaust closing and intake opening if you are turbocharged.

Low end grunt is such a beautiful thing. Especially in rush hour stop-n-go traffic.

Please note that the "zero" mark on your adj gear is likely nowhere near OEM "zero". On the three that I have used, findanza, FM and some other off brand, none read "zero" when they were aligned to the OEM "zero" mark.
You can either degree in your cam to factory specs, Or, an easy way is to install a pointer and first line it up with the OEM sprocket; then line-up / zero-out your adj sprocket to the pointer and re-mark it for "zero". Check out how far "off" these were. Worse, the blue sprocket's holes weren't drilled symmetrically, which significantly limited the available adjustment range.


https://cimg8.ibsrv.net/gimg/www.mia...bbe844af41.jpg
https://cimg3.ibsrv.net/gimg/www.mia...3d8bebbc43.jpg
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did you take those pictures with your dick?

?Que?

I'll jump into this thread since I've been dealing with similar issues over the last week.

I bought cheap Ebay adjustable cam gears and noticed that they didn't come close to matching the OEM gears. They were about 10° out of timing. I tried to adjust them but the slots for the adjustment weren't long enough to get them right. Even with them all the way at the end of the slot they didn't line up. You can see the difference between the two below. The Ebay gear is below the OEM one and you can see the alignment of the center slots is still off.
Attachment 229650

I took the gears to work and milled in extended slots to get the correct timing to the gears. The gears and the slots are now within .25° so I'm pretty happy with that. The problem I noticed now is that the timing triggers are off in relationship to the actual gears. Not by much (<2°) but still off compared to the OEM locations. The triggers are fixed in relationship to the gears so there's no adjustment that can be made for those. I measured everything on a CMM at work so I know it's accurate.
Attachment 229651

So my question is how accurate, timing wise, do the triggers need to be? I'm guessing it won't make any difference but thought I would ask.

I didn't realize when you originally told me of the problem that those were going to be off as well.

If the cam timing and the crank timing are off from each other then you might lose sync in the computer. Remember that the cams turn more slowly than the crank. 2 degrees at the cam is 4 degrees at the crank.

Even though you put in some machine work I would run the factory cam gears. There is nothing to be gained in your build by having adjustability in the gears.