Jan 25, 2017 update to the BMW M3 project car

Pumped for Pistons

Oooooooh, shiny!
Seriously, though: These are awesome!

We’re pretty sure that even a billet cat litter scoop would look awesome. Nevermind the new pistons and connecting rods for our LS1-swapped BMW M3. The best part of engine building is unwrapping shiny new parts, and we spent a few minutes instagramming once the UPS guy dropped these off.

What exactly are these? Pistons from JE Pistons and connecting rods from K1 Technologies. We’re only planning to build this engine once, and these spendy parts should be cheap insurance against anything we throw at it in the future.

How do you pick pistons from a catalog? Simple: Measure, measure, and measure some more. The correct piston is the one that fits the measurements you aren’t changing–like block height and rod length–and will create the measurements you are changing–like compression ratio. We’re aiming for about 10:1 compression. We’re also planning for a .007-inch overbore, which should clean up our cylinder walls, give us a little bit of a displacement bump, and greatly increase our head selection by providing more room for big valves.

What are we doing ordering pistons before we even started the machine work on our block? That’s a trick question–it’s dumb to start honing before there’re pistons in your hand. We’ll get to the reasons why in the next update.

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Comments

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Toyman01
Toyman01 MegaDork
1/25/17 12:51 p.m.

...look awesome...

These two words are deserving of some pictures.

Tom Suddard
Tom Suddard Associate Editor
1/25/17 1:20 p.m.

Sorry, Toyman. Not sure why the photo wasn't originally posted. I updated the first post.

84FSP
84FSP Dork
1/25/17 1:25 p.m.

Yumm billet sexieness.

APEowner
APEowner New Reader
1/25/17 2:41 p.m.

Hmm, a billet cat scoop. I could make one of those. I wonder if my wife would like one for Valentines day...

Toyman01
Toyman01 MegaDork
1/25/17 5:13 p.m.
Tom Suddard wrote:

Quoted for the pure awesomeness of machined metal.

If diamonds are a girl's best friend, machined metal is a man's.

Thanks for the pictures.

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