Bottom End Buildup...

[geoffinbc]

Ok so what do afetrmarket units get its signal from? It must be from something on the cam or crank or else it will batch fire off an ignition pulse or external trigger.

[Corpse]

From Gm's perspective, technically speaking, the cam sensor is the only way for SFI to work with multiple cam grinds without changing computer or electronic's settings. Basically, without it, there would be more hassle as you would have to change settings for a different cam.

So, I guess it is a good method, although, I think if you do not have a cam sensor working, it should revert to cam specs in software of the stock cam used. But, you can't get what you wnt so, the sensor really was a good aproach from gm.

The only problem I have with it is the whole deal of compatability issues. Ie: Different cams, different year cams.

"if the cam were retarded 4 degrees or advanced" - With the cam sensor this would work perfectly with the computer. This is one reason why the sensor is a very good thing. Without the sensor, it would be off. With non-SFI it would be no problem.

-Dave

[bszopi]

Different cams in different years? All the SFI cams are the same... only the trigger has changed.

[Corpse]

Not Different Cams in different years; Different Cams, Different years. I was shooting out a few possibilities. Different Cams - Older cams are not SFi compatible along with any cam without a sensor ring. Different years - The Sensor ring has changed and, so has the sensor, what, 3 times?

I myself wonder why they changed the cam sensor setup over the years.

-Dave

[xxrollin]

My self also. I'm not using SFI, I'm using Bank to Bank. I lite clicking noise at idle but at 2000RPM's its gone. A crank trigger was what I was really getting at. Just couldnt think of the term a few days ago. Anyway, what is the cam everyone claims to use, the Compucam?? So is this a roller or flat tappet, and does it have a cam senser. I'm always hearing people recommend it to everyone. Spec's?

Back to topic, we are off big time......

Anyone know who's stocking forged pistons for either the 3100-3400.. 100 a piece is common, so is there someone out there cheaper and ready to ship?? How about rods. Some good rods. Crower is the cheapest I've seen but they take forever and then you'll have to have the big end narrowed.. Anyone got any good info on internal parts they use or know who can supply??