Piston Slap: Is It Piston Slap? Ja-nee, Baby!

Sajeev Mehta
by Sajeev Mehta
piston slap is it piston slap ja nee baby

Mu-een (from Cape Town, South Africa!) writes:

Hi I would like to know what is the difference sound of a tappet noise, or bad rocker, or a piston slap. Thanks regards.


Sajeev answers:

I suspect that –for most engines– piston slap is a deeper, more resonant sound than an out of whack tappet. Pistons are bigger and buried further in the engine (usually) than tappets, it’s gonna have a different sound by design. Conversely, you could easily isolate the two sounds with a decent mechanic’s stethoscope, or with a cheap one. So for whatever vehicle you own down in Cape Town, try isolating the noise with a stethoscope…or maybe just a loooooong screwdriver against the cam/valve cover on the top of the motor.

Now on to the important implications of this letter. Put another way, OH MY DAMN SON U KNOW WHAT THIS MEANS? We got us some Piston Slaps from North America, South America, Europe, Asia, Australia…and now Africa!

TTAC RULEZ THE WORLD! This is Panther Love with an LSX-FTW swap: a fantastic combination of wonderful things in a singular moment.

Wait…is Antarctica a continent too?

AND they drive cars down there?

Do they read TTAC?


We were sooooo close to world domination!

Send your queries to sajeev@thetruthaboutcars.com. ESPECIALLY IF YOU ARE FROM ANTARCTICA. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.

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3 of 14 comments
  • Art  Vandelay Art Vandelay on Apr 16, 2013

    They all sound like a large woosh coming from your wallet.

  • Raph Raph on Apr 16, 2013

    LSx swap into a pather! Have the gods no mercy!!!! That ain't panther love. Panther love would be FRPP 5.0 MOD block with a stroker crank making it dang close to 330 cubes topped off with a set of Trick Flow 2v heads and a nice set of cams. I swear if I ever get a heap of money, I'm doing a road-runner(Boss 5.0) MT-82 and 8.8 swap into a nice old 67 Nova.

    • JaySeis JaySeis on Apr 17, 2013

      I'm with you and I'd cram an FE in into say...a C4 'Vette. Maybe a solid front axle just for fun.

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