my '89 ran well up to a bit over 200K.....as the compression went so did the super torquey SOTP feel you normally get upon launching from "full" stop....still ran hard though....once it got moving.
Higher Mileage C4s vs Low
Thread Starter
Melting Slicks
Joined: Sep 2006
Posts: 3,194
Likes: 27
From: Monroe Twp, NJ
Higher Mileage C4s vs Low
Does a C4 (any year) with 100,000 plus miles run slower than a identical C4 with low mileage? I was told high mileage cars loose compression and run slower. Is this true?
Racer
Joined: May 2009
Posts: 421
Likes: 2
From: van buren ar
i think that typically a higher milage car will be slower and make less power,however higher milage cars that have be well maintained could benefit from a reduction in rotational friction,due to increased bearing clearance.so i beleve that it can go either way.
Safety Car
Joined: Aug 2008
Posts: 4,344
Likes: 48
From: San Marcos CA
People sometimes put too much emphasis on the engine, but the car chassis/drivetrain is very important to how a car runs and what fuel economy it gets as well. As always, low mileage is a good indicator given normal circumstances.
Drifting
Joined: Nov 1999
Posts: 1,502
Likes: 12
From: Yorktown Heights NY
A sports car is only as good as its mechanic and the funds he is given to spend 
Bottom line....... quantity/quality of new performance parts = good performance
I'm always replacing/upgrading to keep the edge
Bottom line....... quantity/quality of new performance parts = good performance
I'm always replacing/upgrading to keep the edge
Last edited by 95BLKVette; Jan 10, 2010 at 11:21 AM.
Le Mans Master
Joined: Dec 2004
Posts: 5,488
Likes: 1,352
I wouldn't go that far, a car that is losing compression or has weak valve springs will be slower than one that does not, everything else trans, rear gears weight being equal. A 100K mile LT1 may or may not have lost a little and everything else is NEVER equal, from the brand of tires to the age of the tires to the driver etc. That same car with 100K may run better than when it was new as many times is the case. Cars usually pick up a little as they get some miles on them then and as they wear out they lose a little. Is 100K that point ? It could be however there is no perfect answer. My 89 with 166K ran good still.
Le Mans Master
Joined: Jul 2007
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From: Tampa Florida
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Le Mans Master
Joined: Mar 2004
Posts: 8,700
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From: Ft. Lauderdale Fl
My 96' with over 177,000 miles, has a good power curve and "seat of the pants" feel is as when it had 100,000 miles.
Guess it all in how well it was maintained.
Guess it all in how well it was maintained.
Last edited by runner140*; Jan 13, 2010 at 11:26 AM.
Pro
Joined: Oct 1999
Posts: 515
Likes: 0
From: Nashua NH
you're asking a loaded question...a car with 30,000 miles but still has the original oil from the factory and has never been maintained could blow up tomorrow, where the same car that has been cared for and maintained over its life with 100,000 could run/drive like its barely broken in and run down the track like a Challenge car...
Racer
Joined: May 2005
Posts: 497
Likes: 1
From: Casa Grande Az
Hmmmm
My car with 125k on the clock (at that time) put more horsepower / torque down on the dyno then it was rated for from the factory. Only mods at the time being cold air and catback.
I think with today's oils , and the fact that vettes have been coming out of the factory since 92 using synthetics that mileage may not play as large of a part in it as it used too. Not to mention most of us vette owners are very **** about maintenance.
Thats not to say there will not be exceptions to that rule, but I think its a pretty safe statement to say that the days of your small block chevy falling apart at 80k miles are long gone.
Granted there are other things that wear out over time (mostly tires
), I would however not hesitate to jump in my car (135k miles) at this very second and drive it across country while putting lower mileage cars to shame performance wise.
Just my thoughts.
My car with 125k on the clock (at that time) put more horsepower / torque down on the dyno then it was rated for from the factory. Only mods at the time being cold air and catback.
I think with today's oils , and the fact that vettes have been coming out of the factory since 92 using synthetics that mileage may not play as large of a part in it as it used too. Not to mention most of us vette owners are very **** about maintenance.
Thats not to say there will not be exceptions to that rule, but I think its a pretty safe statement to say that the days of your small block chevy falling apart at 80k miles are long gone.
Granted there are other things that wear out over time (mostly tires
), I would however not hesitate to jump in my car (135k miles) at this very second and drive it across country while putting lower mileage cars to shame performance wise.Just my thoughts.
Racer
Joined: Feb 2008
Posts: 435
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From: Bulverde TX
If you get a C4 like mine was (85 with 160000) it will be slower but that was due to the fact that it was only runnin on 7 cylinders because the cam was missin a lob completely. Also every single lifter except for 1 was mushroomed out so none of the cylinders were firing correctly. But like everyone else is saying if you get a mechanically sound high mileage car it will run just as fast.
Race Director
Joined: Jan 2005
Posts: 10,641
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From: Slidell Louisiana
Recently I had the heads off of a 155K LT1 and the bores had no discernable ridge and the cross hatch was still visible.
Heads were only off to fix an exhuast leak caused by broken exhuast studs.. However, I was the second owner of that vehicle and the original owner performed Mobil one oil changes every 3K miles...and he kept the reciepts to prove it.
(this was on my 95 Impala SS) vert still hasn't hit 70K)
Mike
Heads were only off to fix an exhuast leak caused by broken exhuast studs.. However, I was the second owner of that vehicle and the original owner performed Mobil one oil changes every 3K miles...and he kept the reciepts to prove it.
(this was on my 95 Impala SS) vert still hasn't hit 70K)
Mike
Le Mans Master
Joined: Jan 2006
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From: Woodstock Georgia
I have some experience in this area. I take my 95 coupe to the dragstrip and have raced against other LT1 Corvettes with much lower mileage. While the times are close I have never lost to another LT1 Corvette.
Team Owner
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From: Riverside County Southern California
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My 105,000 miles LT1 runs faster than stock LS1 with the same miles. I love the look on their face and then the magical question.
Is that stock?
Yes it is
Is that stock?
Yes it is
