Flexplate

[minnfats]

I'm doing the 2.8 to 3.4 conversion in an S10 Blazer. I bought a complete 3.4 that (supposedly) is out of a 94 Camaro. All the research I have done says the engine is internally balanced therefore having a neutral balanced flexplate. However, the 3.4 I got has an external balanced flexplate. Any suggestions?

[geoffinbc]

Thats impossible. There were NO external balance engines after 88.

Additionally NO 3.1L or 3.4L was ever an external balance motor.

How do you know it is an external balance flexplate?

If it is truly a 3.4L then it will have castings ribs on the sides that form 3 X's on the side of the block. Also if you remove crank sesnor and peer in with a flashlite you will see a reluctor wheel cast with notches in it.

[minnfats]

Thanks for the information. The flexplate has a counterweight spotwelded on. If I turn the engine so it is at 12 o'clock, there are 3 large holes stamped at 4, 6, and 8 o'clock. So it is definitely weighted to one side. I pulled the crank sensor but did not see a relector wheel. I have to pull the oil pan anyway when I do the swap so it may be there and I just can't see it. The block has the triple -x casting ribs though.

I bought this engine sight unseen and had it shipped to me (hopefully that wasn't a mistake). I have contacted the person I bought it from to see if the flexplates may have been swapped.

[geoffinbc]

Oh if they are just little weights that no problem. Thats just balancing of the metal. If you goto the gallery (transmission section) you will see the difference between internal and external balance flexplates/flywheels

[minnfats]

Well I heard back from the guy I purchased it from and he says it's the original flexplate. I checked out the pictures and mine doesn't look like any of those. I did take a closer look at mine and I what I thought were spot welds holding a counter weight are something else. Also, the holes I referred to before go all the way around. I have my engine on a stand and the flexplate is up against the mounting plate of the stand and it's hard to see. Otherwise, I would enclose a picture of mine. Anyway, I feel like a do have the correct one now. Thanks for all your input.