Super eta vs. "i" Cam Gearing

[modifiede30]

Anyone know if there is a difference. Its been discussed in another topic but no definitive answers have come forth on the topic. I know the head is an "i" casting with single springs, eta cam, and "i" valves. But the cam gearing could create timing issues if its different than an "i", at least if the super eta is the basis for a stroker. The eta cam gear is a couple teeth off from an "i" gear (retarded). This is typically okay to run in a stroker since most performance chips advance the timing. But if you're using a chip designed for a stroker, the timing could be too far retarded to take advantage of the larger "i" cam.

[rs4pro3]

What is the part number on your cam gear? does it have a solid construction or web like spokes?

[modifiede30]

Its up at the shop but I think it was a solid gear.

[rs4pro3]

Eta gear is solid and an I cam gear has 6 spokes in a star pattern.

[modifiede30]

Is the "i" timing more appropriate given the ecu, or the "eta". The ECU is a 1990 325i, with an alpina 2.7l knockoff.

[rs4pro3]

I'm not sure that is if there is a difference, the eta gear and I gear I have both the tdc and locating pins line right up so I'm not sure.

[modifiede30]

I thought in the other post, you said that they were about 2 teeth apart, with the eta being retarded in terms of timing. I'm also now worried about the crank position teeth on the harmonic balancer. If the notching is different between a super eta and "i", than the timing will be off from this as well. Do you know if there are any differences in the harmonic balancers? If you have one lying around, let me know.

[rs4pro3]

Red said that, I just said they look completly different.
and the Harmonic ballancers are different(or are you talking about the main gear for the timing belt on the crank)
The I car uses a toothed Pulse wheel with the main pulley attached to it where as the eta uses a solid disk with the main pulley attached to it.
I'm not sure about the actual gear held on by the crank pulley.
I would just make sure to turn the engine over by hand many many times before it goes into the car.

[modifiede30]

I think I'm okay with the toothed crank wheel since the super eta has the appropriate teeth. I'll line them up before I install to make sure they are in the same places. There's a gap at some point in the teeth which I assume is the trigger point for the sensor. As long as these are in the same position, I should be okay. I'll likely due some of my own testing of the cam gear tomorrow before I drop the engine in to make sure I've got the right ones on the stroker.

[rs4pro3]

ok, View the thread about the springs, Red and I both posted pics of an eta and I cam gear Mine line up but his don't. I pm'ed him about it and he said he has been running and eta gear with his I cam no problems, and said that cam gear came off a race engine that might of had a cam so maybe it was modified somewhat.