Weak link in the C4 drivetrain?
Thread Starter
Melting Slicks
Joined: May 2001
Posts: 3,014
Likes: 18
From: Raleigh, NC
Weak link in the C4 drivetrain?
Hey guys,
I was wondering what the weak link(s) in a C4 (1991+) drive train are? Or in the engine for that matter (L98 and LT1). 6 speed please, no auto here.
Here is an example of what I am looking for, as it applies to an LS1 car.
#1 weak spot is the clutch. Barely adequate for stock HP level. Will be destroyed by agressive driving with stock HP.
#2 weak spot is the 10 bolt rear-end. ET streets and stock HP levels will kill this as well.
#3 prolly the rods, maybe the pistons. The stock engine is pretty good to about 550 RWHP. Expect about 20,000 miles at that HP level if the tune is good.
See what I mean?
Thanks!
:hurray: <----- I love this guy, lol.
[Modified by neat, 1:15 AM 7/7/2003]
I was wondering what the weak link(s) in a C4 (1991+) drive train are? Or in the engine for that matter (L98 and LT1). 6 speed please, no auto here.
Here is an example of what I am looking for, as it applies to an LS1 car.
#1 weak spot is the clutch. Barely adequate for stock HP level. Will be destroyed by agressive driving with stock HP.
#2 weak spot is the 10 bolt rear-end. ET streets and stock HP levels will kill this as well.
#3 prolly the rods, maybe the pistons. The stock engine is pretty good to about 550 RWHP. Expect about 20,000 miles at that HP level if the tune is good.
See what I mean?
Thanks!
:hurray: <----- I love this guy, lol.
[Modified by neat, 1:15 AM 7/7/2003]
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Re: Weak link in the C4 drivetrain? (neat)
L98? The intake. It will choke at 300hp...
LT1? Opti, but it isn't fatal... just annoying...
the ZF6 is killer bullet proof, and the D44 rear is the same!!!!
The factory ZF6 clutch is strong, and will handle 450hp or so...
The internals have their limits, but pistons seem to be the bigger problem... Not good for lotsa NO2...
LT1 blocks, as used in Corvettes, are factory 4 bolt mains!
I hope this helps some...
LT1? Opti, but it isn't fatal... just annoying...
the ZF6 is killer bullet proof, and the D44 rear is the same!!!!
The factory ZF6 clutch is strong, and will handle 450hp or so...
The internals have their limits, but pistons seem to be the bigger problem... Not good for lotsa NO2...
LT1 blocks, as used in Corvettes, are factory 4 bolt mains!
I hope this helps some...
Drifting
Joined: Apr 2000
Posts: 1,803
Likes: 1
From: PA
Re: Weak link in the C4 drivetrain? (neat)
Neat,
The clutches do not fail under "aggressive driving", abusive....sure. There are plenty of road racers that see WOT for 80K+ miles with no failure. Clutches get toasted when slipped under full load from a standstill until it stinks like a Freightliner on a 3 mile hill. The same thing will happen to a $130K Mercedes or Ferrari, if you do clutch-slipping 0-60 launches every day. These vehicles do not have marginal clutches. It is the marginal IQ of the pilot that creates problems.
Cars are carefully engineered to provide reliability with factory configuration. I would not categorize such issues as "weak links" when high RPM 550 HP mods, NOS or ET drag tires are installed. Something has to give.....either traction or hardware. You pick it.
The clutches do not fail under "aggressive driving", abusive....sure. There are plenty of road racers that see WOT for 80K+ miles with no failure. Clutches get toasted when slipped under full load from a standstill until it stinks like a Freightliner on a 3 mile hill. The same thing will happen to a $130K Mercedes or Ferrari, if you do clutch-slipping 0-60 launches every day. These vehicles do not have marginal clutches. It is the marginal IQ of the pilot that creates problems.
Cars are carefully engineered to provide reliability with factory configuration. I would not categorize such issues as "weak links" when high RPM 550 HP mods, NOS or ET drag tires are installed. Something has to give.....either traction or hardware. You pick it.
Team Owner
Joined: Sep 2001
Posts: 62,097
Likes: 1,724
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Re: Weak link in the C4 drivetrain? (neat)
ZF6 is near bullet proof, synchros do seem to go bad eventually, but the clutch is usually fine for a long time.
D44 rear can handle slicks down to 1.4/1.5 60' times, past that and its hit or miss.
The LT1 and L98s pistons are hyper and cast respectively, not great for juice. 85 L98 has TRW forged pistons. I wouldnt put more than say a 100 shot on the hyper/cast pistons, but thats just me.
The intake and exhaust manifolds are pretty weak, in terms of HP potential.
D44 rear can handle slicks down to 1.4/1.5 60' times, past that and its hit or miss.
The LT1 and L98s pistons are hyper and cast respectively, not great for juice. 85 L98 has TRW forged pistons. I wouldnt put more than say a 100 shot on the hyper/cast pistons, but thats just me.
The intake and exhaust manifolds are pretty weak, in terms of HP potential.
Thread Starter
Melting Slicks
Joined: May 2001
Posts: 3,014
Likes: 18
From: Raleigh, NC
Re: Weak link in the C4 drivetrain? (Rick93Z07)
I really don't want to turn this into an LS1 clutch debate, but... The clutches in LS1 powered F-bodies do fail, quite frequently. Check out the drive train section on LS1.com. Most are gone in less than 40k. I really doubt all of those people have had failures due to their marginal IQ. I dunno though, maybe?
Thanks for all the info guys! I really appreciate it. Anything else I should know about 6 speed drivetrains?
Thanks for all the info guys! I really appreciate it. Anything else I should know about 6 speed drivetrains?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
10 Things C8 Corvette Owners Hate (But Won't Tell You)
Joe Kucinski
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!
Brett Foote
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)
Joe Kucinski
Team Owner
Joined: Sep 2001
Posts: 62,097
Likes: 1,724
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Re: Weak link in the C4 drivetrain? (neat)
I really don't want to turn this into an LS1 clutch debate, but... The clutches in LS1 powered F-bodies do fail, quite frequently. Check out the drive train section on LS1.com. Most are gone in less than 40k. I really doubt all of those people have had failures due to their marginal IQ. I dunno though, maybe?
T56 is not nearly as stout as ZF6.
