High compression pistons, need forged rods?

[MIKe30]

Yes.

So there really is no option other than MLS or custom gasket. Now I have a complete top end gasket kit for nothing, that is too late to return. Any idea on the oem bolts vs. arp's?

[matt]

OEM bolts everywhere.

I think your best option is 86.5mm pistons and a stock HG.

[MIKe30]

OEM bolts everywhere.

I think your best option is 86.5mm pistons and a stock HG.

Thanks. And good. I actually prefer your suggestion, but he says it's about 86.5 now and the scoring hasn't cleared up. You think a rehone to fit true 86.5mm pistons will clean it up? You can still feel it with your fingernail.

[matt]

I have no idea what will clean it up... I would trust my machinist.

If it were my motor, I would get an M50 block and bore it out to 86.5 then use the S52 parts and custom pistons in it. (get the pistons first and take them with the block to the machinist.) Have them gap your rings as well.

[MIKe30]

Made some decisions. It's going to be 87mm CP 11:1 pistons w/oem head gasket and head slightly milled to get somewhere close to 11.15 or 11.2:1 compression.

Should still provide nice power, and have enough breathing room to not be self destructive on 93.

[mazur]

Made some decisions. It's going to be 87mm CP 11:1 pistons w/oem head gasket and head slightly milled to get somewhere close to 11.15 or 11.2:1 compression.

Should still provide nice power, and have enough breathing room to not be self destructive on 93.

Sounds like a sweet plan. Good luck and don't forget to post your build with some pics :D

[e30polak]

sounds like a sweet plan. Good luck and don't forget to post your build with some pics :d

x2

[MIKe30]

Sounds like a sweet plan. Good luck and don't forget to post your build with some pics :D

x2

Thanks guys. I ordered them today, should be at Jay's sometime tomorrow.

While I was on the phone with VAC last night, the gentleman I was talking to was telling me how much better they're cam is than sunbelts. He says it's also more agressive than schricks, but they're easier on the valvetrain. I'm 99% sure I'm going with bimmerworld, but because of our conversation last night - he informed me today that in about 2 weeks they will be testing back to back VAC cams vs. sunbelts on a 36k 99 e36m3. We'll see if they come through.

[e30polak]

Thanks guys. I ordered them today, should be at Jay's sometime tomorrow.

While I was on the phone with VAC last night, the gentleman I was talking to was telling me how much better they're cam is than sunbelts. He says it's also more agressive than schricks, but they're easier on the valvetrain. I'm 99% sure I'm going with bimmerworld, but because of our conversation last night - he informed me today that in about 2 weeks they will be testing back to back VAC cams vs. sunbelts on a 36k 99 e36m3. We'll see if they come through.

Get the sunbelts. Then have someone adjust your cam gears. throw it back on the dyno, and send it to Bimmerworld for a retune. There are all the threads about Sunbelts on BFC for a reason. Stick with whats proven so I will be inspired by the numbers you put down! :twisted: