Ford Twincam + BMW m10 = hawtness

[Guest Anonymous]

So far after doing to some math on a slow morning at work I found an old engine spreadsheet with many notes on it in my archives. This was in effect a real blessing as it kept records of all my rod weights and my piston weights from when I measured them before. Stock flat top piston with stock wristpin weighs in at 721 grams. The wrist pins supplied with the mahle motorsports forged mustang pistons are 110 so a mustang flat top with stock mahle motorsports pin is 465grams. A savings of 256grams per cylinder in pistons alone. Utilizing some DLC coated titanium wristpins I have I can cut the mahle and pin weight down to 410 grams (not the 50% I had hoped for but still very nice). 311 grams per cylinder. the connecting rods with their length will save us 2% in piston acceleration essentially giving us about 180RPM extra. The weight reduction of the mahle piston with ti pin alone (assuming rods weighed the same) will have the same pulling load on the rod bearing at 8500rpm as the engine running a stock piston at 6350rpm. Now piston speed is way up but the force on the connecting rod is tiny. I doubt we'll have any issues with rods coming apart at full song.

The torque should be up as well as engine response to answer the question earlier. The longer rod gives the piston better leverage on the crankshaft to increase torque. Also the engine won't spend it's time accelerating and slowing down heavy components.

[Guest Anonymous]

I wish there was an edit button..

rod to stroke ratio of about 1.85:1 makes me giddy.

[cheechthechi]

Updates?

[2002Targa]

Any new progress??? Love the thread/idea...

[PatAllen]

Can i ask you why do you change anything in the bottom end, i mean, you want to fit in some sort of flat top pistons isnt it ?

why dont yuo just keep the original flat top ones and just try to work out the head fitement ?

...or the ones you try to fit are not flat tops...

[Guest Anonymous]

Sorry had some family issues come up in the last few weeks... no time to devote to this right now... I'll have more in the next week or two...

the reason for chaning the bottom end is this. The pistons are super light. and the rods are replaced with off the shelf eagles. Pat you know.. forged pistons and rods for a m10 for $700ish is a steal. The goal is to spin it to kingdom come. Flat tops and mustang head are 11.5:1ish so should make for a nice powerband.

[PatAllen]

Sorry had some family issues come up in the last few weeks... no time to devote to this right now... I'll have more in the next week or two...

the reason for chaning the bottom end is this. The pistons are super light. and the rods are replaced with off the shelf eagles. Pat you know.. forged pistons and rods for a m10 for $700ish is a steal. The goal is to spin it to kingdom come. Flat tops and mustang head are 11.5:1ish so should make for a nice powerband.

ok, i see. high rpm.

thanks.

[Guest Anonymous]

flat tops and M10 head make for a 7000RPM turbo screamer with durability out the wazoo..

[PSloan]

Did you say 11:1 and turbo?

[Guest Anonymous]

If you run the mustang pistons with a stock head... you've got a forged bottom end perfect for turbo'ing at 8.3:1.

The mustang head with flat tops is 11.5:1 so it's NA only

THey make a dished mustang piston that will back it to 9:1 so you could then have a DOHC turbo'd m10 engine

[jahshines]

God bless you if you complete this.

[themoose]

What specific rod/pistons/pins/rings are you using? I can wait to get a 16v head but a cheaper, better alternative with the better rod ratio would be awesome! Not to mention I'll be due for an engine rebuild soon, with a turbo!

Thanks

[Guest Anonymous]

What specific rod/pistons/pins/rings are you using? I can wait to get a 16v head but a cheaper, better alternative with the better rod ratio would be awesome! Not to mention I'll be due for an engine rebuild soon, with a turbo!

Thanks

I'm interested also in the piston/rod also. Is the Eagle rod big end diameter the same size as the M10?

My 400hp M10 came apart last week and looking for a better bottom end.

[robspeed]

God bless you if you complete this.

ditto/amen!

[canadapierre]

Looking forward to some updates dear Oldguy! Hope all the family stuff is worked out.

I hate to see this thread dropping off to the second page as time goes by...