The Rodding Roundtable

Motorhead Message Central => Rodder's Roundtable => Topic started by: phat46 on August 23, 2020, 07:24:36 PM

Title: Quench question
Post by: phat46 on August 23, 2020, 07:24:36 PM
Another question for the engine building gurus here. What quench number do you like or recommend? I know the standard answer is .035-.045 for a mild SBC. I am looking at .037 with an .051 head gasket and was told that might cause pinging. I would like to be closer to .040 quench, but can't find a .054  gasket. Am I too worried?
Title: Quench question
Post by: chimp koose on August 24, 2020, 12:41:12 AM
too worried. When quench gets MORE than .060 then you can get a problem with detonation . The proper term is squish, it is used to generate turbulence in the chamber to promote even charge density. I looked into Singh grooves but it seems more of an observation evaluation more than empirical data to support it . If you want to do some research into deck heights I would suggest you go to a site called speed talk and search out the topics you are interested in .
Title: Quench question
Post by: phat46 on August 24, 2020, 07:40:36 AM
Quote from: "chimp koose"too worried. When quench gets MORE than .060 then you can get a problem with detonation . The proper term is squish, it is used to generate turbulence in the chamber to promote even charge density. I looked into Singh grooves but it seems more of an observation evaluation more than empirical data to support it . If you want to do some research into deck heights I would suggest you go to a site called speed talk and search out the topics you are interested in .

Thanks, I understand the term and the reason for it, just worried that I might be too tight. You can read all kinds of things online, like Smokey Yunick saying absolutely never less than .038.and others saying .030 is fine. I see the terms quench and squish used interchangeably and also as two separate things....I should quit reading so much and just screw the motor together! 😄
Title: Quench question
Post by: rumrumm on August 26, 2020, 10:29:51 AM
You should be fine. It doesn't get iffy unless you are running on the edge of dynamic compression parameters.