Pistons - Old vs New

[dougie]

Thought I'd share a comparison between the OEM piston and rod system and what now can be used to obtain the highest level of performance.

The difference between the stock piston/rod and a high-performance piston/rod combination is 10oz. in weight, and a whole lot more total real performance (horse power & torque).

 

[Jerry]

What is your compression ratio with the new pistons? And what octane do you have to run?

 

[Bob_Spidell]

The 'skinny' rings have to reduce friction quite a bit, too, and probably reduce bore wear. Most/all new cars have similar, the downside being possible higher oil consumption. Manufacturers often claim 1qt/1K miles is 'normal;' i.e. not cause for warranty repair (typical or worse than a well-built Healey engine).

 

[red57]

I agree with Dougie, However, there are less extreme options than Dougie's for a street car. I used Carrillo pistons and rings in my new motor but kept the stock rods (much cheaper). The Carrillo piston/ring/pin set saved 5.1oz from stock piston/ring/pin set. And total cost for set was $835 vs Moss list of $489 (an extra $350). Bob is correct about much less parasitic drag and cylinder wear from 3 thinner rings.

 

[Rob Glasgow]

I just saw a post that said a Formula 1 piston costs $65,000 each and the engine cost $9 million. Can that be so? Sure makes our engine rebuilds seem reasonable.

 

[Michael Oritt]

Why would each F1 piston cost more than $65,000?!

We all know that F1 cars are producing a tremendous amount of power and reach high speeds on the racing tracks, but why would it cost that much to produce a single-engine piston! The cost

engineerine.com

 

[John Turney]

As an old racer neighbor told me: "Speed is a function of cubic dollars."

 

[Randy Forbes]

Dougie, I would expect an anti-scuff coating (dry-film lubricant) on the skirts, but I'm surprised they don't have a thermal barrier on the crown.

Edit: but those pop-up pistons and rods sure are pretty!

Adding an oil shedding thermal dispersant to the undersides, well that's just gravy...

The S54 engine I just built using store-bought Mahle Power-Pak pistons meant that I didn't have to do the polymer coating process myself!

https://www.us.mahle.com/media/usa/motorsports/bmw-s54-b32-webpage.pdf

 

[dougie]

Hello Randy -
The skirt coating was something I added after receiving the pistons from the custom manufacture. I'm still not convinced on the long term life cycle of a thermal barrier on the crown/dome on a race motor. The NASCAR, NHRA, CART, etc. guys tear down their motors 10:1 to me and I'm really trying to make it 50:1.

 

[dougie]

What is your compression ratio with the new pistons? And what octane do you have to run?

Hi Jerry -

I run a 12.5:1 compression ratio on 110 Sunoco or VP leaded race fuel only. I should have clarified, this is build is for my dedicated vintage racing
1957 100-6 MM.

 

[dougie]

I agree with Dougie, However, there are less extreme options than Dougie's for a street car. I used Carrillo pistons and rings in my new motor but kept the stock rods (much cheaper). The Carrillo piston/ring/pin set saved 5.1oz from stock piston/ring/pin set. And total cost for set was $835 vs Moss list of $489 (an extra $350). Bob is correct about much less parasitic drag and cylinder wear from 3 thinner rings.View attachment 86916View attachment 86917

Hey Dave -

Those look pretty nice, what were you running in your racing days?

 

[Rocky_LC]

Getting the last 5% of performance can cost as much as getting to 95% capability…

It’s worth it if you are Racer. Maybe not so much if you are just blasting around on the street….

But it’s fun!

 

[DrEntropy]

RE: That WISECO article, last V-12 Ferrari engine I rebuilt got Wiseco pistons. They sent us 13 for some reason, so that's here as a conversation piece. One of the old ones (stamped #12) is currently on my desk in the garage as an ashtray.

Ferrari wanted some astronomical amount and a wait of months. Wiseco was a few hundred and six weeks, IIRC.