cam "blue printing"

[quadzjr]

I have heard.. not going to mention from whom.. but they got stock cams from supplier A.. then drilled there own dowl pin at the at teh degree that they found most beneificial within the stock range. Fortuantely for them the stock cams range was apparently failry broad. A fair stretch of the rules that if jsut left up to a degree wheel and dial gauge would be legal. The cams got protested, however the protested party was handed the portest then told to bring there car up tech. Since the messenger left, they were able to swap in stock cams before having to pull them again in tech. (there was a reason why the car didn't run to the tech shed.. the timing was WAY off.. they jsut threw the cams in there.. didn't have time set them up.)

Side note.. As a vote of relief this was not on a IT car.

[lateapex911]

The cams got protested, however the protested party was handed the protest then told to bring there car up tech. Since the messenger left,

CRASH! Steward totally dropped the ball, huge misconduct. Totally against the book. Once the evidence is out of the control of the stewards, it's tarnished and the whole deal is screwed. The protester should have written the Steward up.

[MMiskoe]

Ahhh, the beauty of running a Miata. All the cam specs are on file in Topeka.

Yes, but! Once they are out of the car you have no way of measuring the relative difference between intake & exhaust timing...... Ahh the beauty of dual cam designs.

[quadzjr]

Couldn't you say that about all cams? In the case of the DOHC motor required to us e an offset key. the only timing changes available are +/- a tooth.

-Which I have seen some motors benefit from moving the a cam a tooth relative to the other.. (motorcross Yamaha 450 engines produce significant gains from doing this, and my street MR2 turned was a gas saver! I fixed the cam timing on teh MR2 and now it is faster, but gas mileage went to crap)

[Greg Amy]

Once they are out of the car you have no way of measuring the relative difference between intake & exhaust timing...

If that's important to you, specify measuring relative cam timing in your protest. But, if all you protest is the cam itself, you never asked for that to be looked at anyway...

Don't forget to spec checking the gear(s) for altered keyways (compare it to known stock example), and/or widening of the keyways (allows you to move the cam timing, and it don't take much), and/or modified timing chain (though that's REALLY taking it to an extreme level of cheating...) - GA

[quadzjr]

Don't forget to spec checking the gear(s) for altered keyways (compare it to known stock example), and/or widening of the keyways (allows you to move the cam timing, and it don't take much), and/or modified timing chain (though that's REALLY taking it to an extreme level of cheating...) - GA

How would you alter a timing chain to get a +/- degrees? Either case.. that is a bit extreme but isn't the use of offset bushings (SOHC) and keys (DOHC) legal? I would think your best bet is to just put a degree wheel on the thing and dail gauge.

However does the Tech shed have the proper tools to do such a job.. I.e. piston stop, degree wheel, dial gauge, etc? I guess that is the point of the adance warning.

[Greg Amy]

How would you alter a timing chain to get a +/- degrees?

Use/make one with different-length links.

isn't the use of offset bushings (SOHC) and keys (DOHC) legal?

Only on the crankshaft pulley.

However does the Tech shed have the proper tools to do such a job

Not likely.

GA

[GKR_17]

isn't the use of offset bushings (SOHC) and keys (DOHC) legal?

Only on the crankshaft pulley.

And only to bring the timing back to factory specs.

[Ron Earp]

Don't forget to spec checking the gear(s) for altered keyways (compare it to known stock example), and/or widening of the keyways (allows you to move the cam timing, and it don't take much), and/or modified timing chain (though that's REALLY taking it to an extreme level of cheating...) - GA

And cam gears that have the drive pin and mark re-indexed, another extreme example.