FPC article
Pro
Joined: Sep 2005
Posts: 539
Likes: 415
From: RS KY
.....My guess hasn't changed, I still think it'll be a short stroke/long rod combination, ~3.2" stroke to help lessen the secondary combined with a ~4.07" bore if it's a 5.5L. The stroke gives piston speeds at 8000-9000rpm that are within the realm of "it's been done before", while the bore should allow some great flowing heads/valves.....
Agreed. Also interesting to note that these bore/stroke measurements are essentially the same as the 4.0L 911 GT3 engine. A good thing.
Race Director
Joined: Nov 2017
Posts: 12,759
Likes: 10,657
From: Prosper TX/Austin TX
2020 C6 of the Year Winner - Modified
If they do decide to go this route, I fear we’ll see posts in the near future similar to those directed at potential C6 Z06 buyers, ie “make sure you get the xyz engine component checked out before purchase, or budget to have it fixed right away”. 
Drifting
Joined: May 2007
Posts: 1,557
Likes: 1,275
From: EV is like bad sex with no moaning
I could live with 672 hp at 3600 lbs. Especially if geared correctly. I would say the ZR1 is years away still, at least 5, so it is confusing how we seen the tt cad leak so early.
Pro
Joined: Feb 2019
Posts: 605
Likes: 1,101
From: SC
All versions of the Gen6 engines were, for the most part, developed in parallel. It wont be the engine hardware that dictates the release timing of subsequent versions.
I don't know, but I would think that the new sub components like suspension, brakes and tranny are what will dictate the time lines for release of the subsequent versions.
I would think they they are also the primary drivers of cost of new versions because they are not shared across platforms like the engine.
What would you guys think of a cross plane crank 32valve 6.x L re-cammed version with a red line of 6900 rpm to replace the LT2? Slightly more hp but MORE torque.
I read "on the internet somewhere" that they would need to make a certain number of these small port lower hp heads to meet some kind of racing rules somewhere.
Last edited by GrandSport 2017; Apr 28, 2021 at 09:49 AM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Melting Slicks
Joined: Aug 2020
Posts: 3,353
Likes: 3,739
I wouldn't think its 5 years away.
All versions of the Gen6 engines were, for the most part, developed in parallel. It wont be the engine hardware that dictates the release timing of subsequent versions.
I don't know, but I would think that the new sub components like suspension, brakes and tranny are what will dictate the time lines for release of the subsequent versions.
I would think they they are also the primary drivers of cost of new versions because they are not shared across platforms like the engine.
What would you guys think of a cross plane crank 32valve 6.x L re-cammed version with a red line of 6900 rpm to replace the LT2? Slightly more hp but MORE torque.
I read "on the internet somewhere" that they would need to make a certain number of these small port lower hp heads to meet some kind of racing rules somewhere.
All versions of the Gen6 engines were, for the most part, developed in parallel. It wont be the engine hardware that dictates the release timing of subsequent versions.
I don't know, but I would think that the new sub components like suspension, brakes and tranny are what will dictate the time lines for release of the subsequent versions.
I would think they they are also the primary drivers of cost of new versions because they are not shared across platforms like the engine.
What would you guys think of a cross plane crank 32valve 6.x L re-cammed version with a red line of 6900 rpm to replace the LT2? Slightly more hp but MORE torque.
I read "on the internet somewhere" that they would need to make a certain number of these small port lower hp heads to meet some kind of racing rules somewhere.
"Horsepower sells cars, torque wins races"
-- Carroll Shelby
Melting Slicks
Joined: Aug 2003
Posts: 2,245
Likes: 2,176
From: Cary NC
The issue I would see with an owner swapping a crank like this into his FPC 5.5 C8Z would be the firing order change, and the ECU.
The Consigliere
Joined: May 2006
Posts: 23,003
Likes: 6,045
From: 2023 Z06 & 2010 ZR1
I"m really, really hoping the ZR1 gets a cross plane crank and twins. Would be nice to have that as a strong power package in an engine I wouldn't have to worry so much about it living to 50k miles.
Burning Brakes
Joined: Nov 2007
Posts: 999
Likes: 867
From: Williamson County, TN
gee I remember the RATTLER a bunch of pucks inside big holes that dampen the vibration with no elastomer to wear out.
and yes they DO rattle. Curious how well it actually worked!! That design faded away for dampers as far as I know
The GM engineers have their work cut out. A brand new engine with FPC sounds like they are walking the same path as ford, which dropped it like a bad habit
curious what magic GM engineers can work that ford didn't think of. They aren't dumb over there either!
I'm not sold on the FPC. I know it has some slight advantages, but it's uber costly and brings a whole heard of real issues for that small incremental gain.
FPCs seem to be the new "darling" of the auto exotic world, but I can't help but wonder if they are so wonderful why doesn't NASCAR and other drag race cars that go uber rpms flock to them.
Time will tell if the juice is worth the squeeze.
and yes they DO rattle. Curious how well it actually worked!! That design faded away for dampers as far as I know
The GM engineers have their work cut out. A brand new engine with FPC sounds like they are walking the same path as ford, which dropped it like a bad habit
curious what magic GM engineers can work that ford didn't think of. They aren't dumb over there either!
I'm not sold on the FPC. I know it has some slight advantages, but it's uber costly and brings a whole heard of real issues for that small incremental gain.
FPCs seem to be the new "darling" of the auto exotic world, but I can't help but wonder if they are so wonderful why doesn't NASCAR and other drag race cars that go uber rpms flock to them.
Time will tell if the juice is worth the squeeze.
Certainly they care more about being fast and reliable for endurance racing than just sounding good?
The magic is staring us right in the face I believe, look to the racing program if you need an example of what GM has in store for us perhaps. It’s not new tech, it’s been being tested under our noses quite vigorously in fact. Plus or minus some MR engine mounts to counter any vibration from such a large displacement FPC motor I think what we see in the racing program will translate to what we see in the production Z06.
“Horsepower sells cars, NA Flat cranks win races.”
-Benjamin Franklin
Last edited by Aozora; Sep 13, 2021 at 04:30 PM.
Burning Brakes
Joined: Nov 2007
Posts: 999
Likes: 867
From: Williamson County, TN
It’s settled then! The Z06 is going to be a 5.5L NA FPC V8 making at least 600 ponies. (I’d guess closer to 650) I suppose that means we will see some serious weight saving measures taken as well.
Hows it feel to be wrong all you “TT and 3800 pound” nay-sayers?
Hows it feel to be wrong all you “TT and 3800 pound” nay-sayers?
Le Mans Master
Joined: Aug 2000
Posts: 5,529
Likes: 1,943
From: Austin Texas
617 from 5.5L is a lesser tune than Ferrari 360 Challenge Stradalé (2005) !! can easily happen.
Le Mans Master
Joined: Aug 2000
Posts: 5,529
Likes: 1,943
From: Austin Texas
Certainly they care more about being fast and reliable for endurance racing than just sounding good?
The magic is staring us right in the face I believe, look to the racing program if you need an example of what GM has in store for us perhaps. It’s not new tech, it’s been being tested under our noses quite vigorously in fact. Plus or minus some MR engine mounts to counter any vibration from such a large displacement FPC motor I think what we see in the racing program will translate to what we see in the production Z06.
Instructor
Joined: Aug 2021
Posts: 139
Likes: 42
From: Newnan, GA
THIS... so..... reliability.... can anyone give me a warm and fuzzy feeling? this really didn't. I don't intend to let mine sit any more than it has to. I will daily drive this thing...and I drive a **** load. 100,000 mile throw away? people don't keep super cars much over 10,000 and a Lambo with 30,000 miles or more is considered pretty high miles. as a mechanic i know things will need maintenance... but this part of the article wasn't confidence inspiring. ive seen plenty of C5's and C6's with 120,000+ miles
Last edited by JWP6114; Sep 13, 2021 at 10:47 PM.
Drifting
Joined: Oct 2018
Posts: 1,539
Likes: 1,170
From: C&D 10 Best loop
GM’s record with bespoke engines is…not good.
Last edited by Zaro Tundov; Sep 14, 2021 at 01:04 AM.
Le Mans Master
Joined: Aug 2000
Posts: 5,529
Likes: 1,943
From: Austin Texas
These are not the ones the owner gets in once a month and redlines it from garage to garage through every gear.
Driven in an adult manner, Ferrari engines are nearly bulletproof.
It is the ones that sit around for weeks at a time that have more problems than the ones driven every day.
These are not the ones that get listed "for sale" because the owner still wants to drive it.
Last edited by MitchAlsup; Sep 14, 2021 at 05:39 PM.