2023 ZO6 LT6 engine spec - ZR-1 Net Registry Forums

lfalzarano · 10-26-2021

From the assistant chief engineer who states the LT6 DOHC will produce 670HP at 8400 RPMs!

https://youtu.be/_uta6RWwx7s

Image1635277788.081125.jpg
IMG_4568.jpg

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WARP TEN · 10-27-2021

A great video of the engine and a great explanation of how it works. Maybe I didn't hear it, but I don't think Jeremy asked about how they overcome the inherent increased vibration of a flat plane crank engine, something I would like to hear more about. I would bet that cutaway engine cost at least $100,000 if not much more. --Bob

tpepmeie · 10-27-2021

Well, with an 80mm (3.15") stroke, the second order vibration should not be too noticeable. The ford flat plane engine has a 93mm stroke, which is getting up there for such a configuration, so they had to resort to a non-traditional counterweight design (and perhaps firing order?) to mitigate the vibrations.

The LT5 LeMans engine had a 92.4mm flat plane crank, and I'm told it shook pretty bad.

I think 80mm was a great choice by GM for this one. Ferrari F136-type engine in the 430 and 458 were 81mm stroke, and I can personally attest that I never even felt nor cared about any vibrations....

XfireZ51 · 10-27-2021

Todd,

The GM FPC avoids the Ford issue due to using the UDUD configuration whereas the Voodoo changed the firing order and needed to add 50# to the counterweights.
Great explanation of what went wrong for Ford found here.

https://www.corvetteforum.com/forums...post1604219016

Also, I have read that GM will be using their magnetorheological system for the motor mounts.

10-26-2021	#1
lfalzarano Join Date: Feb 2011 Location: Clayton, North Carolina Posts: 1,133	2023 ZO6 LT6 engine spec From the assistant chief engineer who states the LT6 DOHC will produce 670HP at 8400 RPMs! https://youtu.be/_uta6RWwx7s Image1635277788.081125.jpg IMG_4568.jpg Sent from my iPhone using ZR-1 Net Registry __________________ Lou[COLOR="Red"][B][SIZE="4"][/SIZE][/B][/COLOR] Last edited by lfalzarano; 10-26-2021 at 03:50 PM.

10-27-2021	#2
WARP TEN Join Date: Apr 2007 Location: Lake Bluff, IL Posts: 2,084	Re: 2023 ZO6 LT6 engine spec A great video of the engine and a great explanation of how it works. Maybe I didn't hear it, but I don't think Jeremy asked about how they overcome the inherent increased vibration of a flat plane crank engine, something I would like to hear more about. I would bet that cutaway engine cost at least $100,000 if not much more. --Bob __________________ 2016 Long Beach Red Z06 #10281 "POPS Z" 1995 Polo Green #409 "WARP TEN"--Haibeck 350/510 package, 4.10s, Hurst, Stock Exhaust with QTP Cutouts --Sold but still running strong 1993 Quasar Blue #161 "HIL KING" --Sold but still running strong, now with more than 120,000 miles 1967 Marlboro Maroon/Saddle Corvette Coupe 300 hp/4-spd --Sold a long time ago ZR-1 Net Registry Founding Member #95 NCM Lifetime Member Favorite Quote--Attributed to Mickey Thompson: "Too Much Horsepower is Almost Enough"

10-27-2021	#3
tpepmeie Join Date: Aug 2005 Location: Fishers, IN Posts: 814	Re: 2023 ZO6 LT6 engine spec Well, with an 80mm (3.15") stroke, the second order vibration should not be too noticeable. The ford flat plane engine has a 93mm stroke, which is getting up there for such a configuration, so they had to resort to a non-traditional counterweight design (and perhaps firing order?) to mitigate the vibrations. The LT5 LeMans engine had a 92.4mm flat plane crank, and I'm told it shook pretty bad. I think 80mm was a great choice by GM for this one. Ferrari F136-type engine in the 430 and 458 were 81mm stroke, and I can personally attest that I never even felt nor cared about any vibrations.... __________________ Todd ____________________________________ *** our email address has changed! info@pepmeierengines.com pepmeierengines.com Friend us on Facebook too: www.facebook.com/profile.php?id=100011443683384 Pepmeier Engine Development Last edited by tpepmeie; 10-27-2021 at 04:44 PM.

10-27-2021	#4
XfireZ51 Join Date: May 2007 Location: Chicagoland, IL Posts: 9,700	Re: 2023 ZO6 LT6 engine spec Todd, The GM FPC avoids the Ford issue due to using the UDUD configuration whereas the Voodoo changed the firing order and needed to add 50# to the counterweights. Great explanation of what went wrong for Ford found here. https://www.corvetteforum.com/forums...post1604219016 Also, I have read that GM will be using their magnetorheological system for the motor mounts. __________________ [SIGPIC][/SIGPIC]Former Membership Chairman Former ZR-1 Registry - BOD 1972 Corvette 4speed base Coupe SOLD long time ago 1984 Corvette Z-51/4+3 SOLD 1992 Corvette ZR-1 Aqua/Gray #474 SOLD 1992 Corvette ZR-1 Black Rose/Cognac #458 2014 Honda VFR Interceptor DX