69 c3 performance limits?
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69 c3 performance limits?
About to take delivery of my first corvette. It is a 69 L68 tri power coupe. My question pertains to how hard to push the car when driving. I've heard you don't want to exceed 80% of redline. I really want to get a feel for what the car can do but am afraid of damaging the engine. It is a 47 year old car. Thoughts?
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I have a 68 L36, 427/390. The motor was a fresh rebuild to stock specs when I bought it 10 years ago. It is pretty much the same motor as yours except for the carbs. Redline is 5,600 RPM's. I like to jump on it from a roll almost every time I drive it. I rarely exceed 5,000 RPM's. I don't see any benefit to getting any closer to redline. Most of the torque and horsepower is achieved at lower RPM's anyway.
How fresh is your motor?
How fresh is your motor?
Last edited by capevettes; May 28, 2016 at 12:09 PM.
Thread Starter
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I have a 68 L36, 427/390. The motor was a fresh rebuild to stock specs when I bought it 10 years ago. It is pretty much the same motor as yours except for the carbs. Redline is 5,600 RPM's. I like to jump on it from a roll almost every time I drive it. I rarely exceed 5,000 RPM's. I don't see any benefit to getting any closer to redline. Most of the torque and horsepower is achieved at lower RPM's anyway.
How fresh is your motor?
How fresh is your motor?
Melting Slicks
Joined: Mar 2008
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From: Meriden CT
As long as everything has been thouroghly inspected and repaired or replaced as neccesary, age is irrelevant. If you are driving a barn find in "as found" condition, you're asking for trouble.
Burning Brakes
Joined: Oct 2015
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Humorously I'D add that unless the German Autobahn is just down the road from your house.
OR you routinely go to the local NHRA eventsat a drag strip..Enjoy the car with it's hp and torque and stay within the limits of the law..and the laws of physics..Serious wrecks or mech failures not on our adgendas..and unless you are under 30 yrs old you probably have nothing to prove..
Drive your Corvette, check all syatems, look, listen..Prove it carefully and thoughtfully..
NEVER let a dodge minivan pass you on the freeway..;and always fill up with 92 octane ethanol free gasoline..Jim.
OR you routinely go to the local NHRA eventsat a drag strip..Enjoy the car with it's hp and torque and stay within the limits of the law..and the laws of physics..Serious wrecks or mech failures not on our adgendas..and unless you are under 30 yrs old you probably have nothing to prove..
Drive your Corvette, check all syatems, look, listen..Prove it carefully and thoughtfully..
NEVER let a dodge minivan pass you on the freeway..;and always fill up with 92 octane ethanol free gasoline..Jim.
Thread Starter
Pro
Joined: May 2013
Posts: 570
Likes: 22
Humorously I'D add that unless the German Autobahn is just down the road from your house.
OR you routinely go to the local NHRA eventsat a drag strip..Enjoy the car with it's hp and torque and stay within the limits of the law..and the laws of physics..Serious wrecks or mech failures not on our adgendas..and unless you are under 30 yrs old you probably have nothing to prove..
Drive your Corvette, check all syatems, look, listen..Prove it carefully and thoughtfully..
NEVER let a dodge minivan pass you on the freeway..;and always fill up with 92 octane ethanol free gasoline..Jim.
OR you routinely go to the local NHRA eventsat a drag strip..Enjoy the car with it's hp and torque and stay within the limits of the law..and the laws of physics..Serious wrecks or mech failures not on our adgendas..and unless you are under 30 yrs old you probably have nothing to prove..
Drive your Corvette, check all syatems, look, listen..Prove it carefully and thoughtfully..
NEVER let a dodge minivan pass you on the freeway..;and always fill up with 92 octane ethanol free gasoline..Jim.
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That's a pretty fresh motor as long as it was rebuilt properly. As long as you aren't hearing any strange metallic noises and you are using a proper motor oil you should be able to enjoy your Big Block as it was designed to be enjoyed.
Team Owner
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I got to drive 69 vettes when they were only a few years old and we drove them like any 16 year old would
They are not that powerful compared to modern cars
Being that old you might experience valve float up around red line
They are not that powerful compared to modern cars
Being that old you might experience valve float up around red line
Melting Slicks
Joined: Oct 2012
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From: Dunedin NZ.
If the engine is sound you should have no problem with the occasional blast near the red line. As others have mentioned, making sure you have the correct oil in the engine would be a priority for me and it was well warmed up before I started stepping on it.
Depending on the condition of the rest of the car the engine might be the least of your worries, make sure the steering and brakes are up to the job:-)
Depending on the condition of the rest of the car the engine might be the least of your worries, make sure the steering and brakes are up to the job:-)
Safety Car
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driving
I agree with staying within the limits on the street and I also understand not going to the track. With that said are there any people out there who raced these cars. My 65 fuelie back in the day was a fantastic car for both street and strip. There was nothing other then another vette that was a challenge and at the track when I raced in the 1/8 I would launch at 6k shift at 7k and turn 7.9 100mph. In the 1/4 I ran 12.3's all day long. Once in awhile if you REALLY want to see push it to its limit. You might be surprised. I was!!
Just a thought
RVZIO
Just a thought
RVZIO
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driving
I agree with staying within the limits on the street and I also understand not going to the track. With that said are there any people out there who raced these cars. My 65 fuelie back in the day was a fantastic car for both street and strip. There was nothing other then another vette that was a challenge and at the track when I raced in the 1/8 I would launch at 6k shift at 7k and turn 7.9 100mph. In the 1/4 I ran 12.3's all day long. Once in awhile if you REALLY want to see push it to its limit. You might be surprised. I was!! Just making conversation.
Just a thought
RVZIO
Just a thought
RVZIO
Safety Car
Joined: Aug 2000
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From: San Antonio TX
The redline is the maximum sustained safe engine speed. An engine's redline is established by, 1): the parts durability (forged pistons, forged crank, special connecting rods and special engine blocks for high performance applications are common) and, 2): engine air flow potential (big port and valve heads, big cam, stiffer valve springs, big runner intake, big carburetor and such).
Burning Brakes
Joined: Oct 2015
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The redline is the maximum sustained safe engine speed. An engine's redline is established by, 1): the parts durability (forged pistons, forged crank, special connecting rods and special engine blocks for high performance applications are common) and, 2): engine air flow potential (big port and valve heads, big cam, stiffer valve springs, big runner intake, big carburetor and such).
Race Director
Joined: Mar 2003
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From: Eustis ( Area 51 Bat Cave ) Fl
Yeah doesn't it suck out loud that some kid in a warmed up import can just spank the hell out of the old cars we thought were so bad....
Curious...in 69 new on the bias plys what did the bb's run in the 1320?
Curious...in 69 new on the bias plys what did the bb's run in the 1320?
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RVZIO
Last edited by SB64; May 28, 2016 at 08:46 PM.
Safety Car
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From: San Antonio TX
Depends upon which '69 BB, but road tests from the day were anywhere from low 13s for the L-88 to mid/high 14s for the lesser 427/390. The 427/435 was a mid 13s car. You can look up the road tests for all the awesome cars of the era.
Burning Brakes
Joined: Mar 2006
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From: Spartanburg SC
Taking delivery of a 47 yo car, you should ask yourself, are the TA bearings , front wheel bearings, rubber bushings , steering box, ball joints, pivot arms 47 yo? At this point, the capabilities of the engine is only one factor in a sustained high speed run. OTOH, I know for a fact those cars would easily run 140+ mph when new. In 69 , the competition for the Vettes were somewhat limited. In 70, the game changed. Hemi Cudas, Challengers, Boss Mustangs were rolled out.
Race Director
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From: Eustis ( Area 51 Bat Cave ) Fl
When I got my first corvette that 72 bb convertible I was young and not too savvy,
The car had a hopped up 454 and stick, the car was in driver condition not pristine, one evening I decided to see how fast it would go, on a little road between Sanford and Smyrna about midnight on a weeknight so it was wicked dark and dead out I pulled over, I wanted to run through the gears, I didn't take off hard as I didn't wanna spin the wheels, in no time I was double the legal limit and creeping past 100, I heard all kinds of noises that just were not right and noticed the hard top only latched at the front was lifting up off the deck in the rear, I wasn't too far past 100 but enough to scare me and back off quickly, on the way home 40-55 seemed so darned slow, I am happy I learned and lived....
The car had a hopped up 454 and stick, the car was in driver condition not pristine, one evening I decided to see how fast it would go, on a little road between Sanford and Smyrna about midnight on a weeknight so it was wicked dark and dead out I pulled over, I wanted to run through the gears, I didn't take off hard as I didn't wanna spin the wheels, in no time I was double the legal limit and creeping past 100, I heard all kinds of noises that just were not right and noticed the hard top only latched at the front was lifting up off the deck in the rear, I wasn't too far past 100 but enough to scare me and back off quickly, on the way home 40-55 seemed so darned slow, I am happy I learned and lived....