Is it bad to redline your car?
- Thread starter buster
- Start date
- Status
7000 RPM redline on my 2.5L V6 Jaguar X-Type W/manual trans. The engine is tiny for this car, so even though it's well tuned by Jaguar, redline is a way of life. 107,000 miles with zero problems.
That's only 417 cubic centimeters per cylinder. 450cc single cylinder motorcycles redline at 11,500 RPM!
Contrast that with a Chevy Corvette 6.2L engine with a similar Redline and 775 cubic centimeters per cylinder!
That's only 417 cubic centimeters per cylinder. 450cc single cylinder motorcycles redline at 11,500 RPM!
Contrast that with a Chevy Corvette 6.2L engine with a similar Redline and 775 cubic centimeters per cylinder!
Originally Posted By: FZ1
The faster it spins:The more that can go wrong. More worried about my auto trans than the engine. I've never redlined my 02 V6 Accord automatic in 116,000 miles.
I'm terrified to drive our 03 V6 Accord because of the transmission. The horror stories that go along with those transmissions is in the back of my mind constantly. We're at just about 70,000 miles without an issue...
The faster it spins:The more that can go wrong. More worried about my auto trans than the engine. I've never redlined my 02 V6 Accord automatic in 116,000 miles.
I'm terrified to drive our 03 V6 Accord because of the transmission. The horror stories that go along with those transmissions is in the back of my mind constantly. We're at just about 70,000 miles without an issue...
Originally Posted By: Cujet
7000 RPM redline on my 2.5L V6 Jaguar X-Type W/manual trans. The engine is tiny for this car, so even though it's well tuned by Jaguar, redline is a way of life. 107,000 miles with zero problems.
That's only 417 cubic centimeters per cylinder. 450cc single cylinder motorcycles redline at 11,500 RPM!
Contrast that with a Chevy Corvette 6.2L engine with a similar Redline and 775 cubic centimeters per cylinder!
Note the redline on the Corvette is 6500 rpm, and I have seen completely stock original bottom ends on these cars with heavy mods run 7500 rpm with no apparent issues.
7000 RPM redline on my 2.5L V6 Jaguar X-Type W/manual trans. The engine is tiny for this car, so even though it's well tuned by Jaguar, redline is a way of life. 107,000 miles with zero problems.
That's only 417 cubic centimeters per cylinder. 450cc single cylinder motorcycles redline at 11,500 RPM!
Contrast that with a Chevy Corvette 6.2L engine with a similar Redline and 775 cubic centimeters per cylinder!
Note the redline on the Corvette is 6500 rpm, and I have seen completely stock original bottom ends on these cars with heavy mods run 7500 rpm with no apparent issues.
I brought my '07 Corolla to the limiter once (believe it was 6,500 rpm) and it didn't buck or cut off or do anything dramatic. It simply stopped pulling and sat there at 6,500 rpm (manual transmission). I was impressed with how smooth it was.
My brother's '99 Corvette will bang off the rev limiter, but it's not all that violent. You get there quickly in it. 4.11 gears, Maggy-Lingenfelter supercharger, etc. You can hardly shift it fast enough to keep it off the limiter in 1st through 3rd gears.
My brother's '99 Corvette will bang off the rev limiter, but it's not all that violent. You get there quickly in it. 4.11 gears, Maggy-Lingenfelter supercharger, etc. You can hardly shift it fast enough to keep it off the limiter in 1st through 3rd gears.
OVERKILL
$100 Site Donor 2021
Originally Posted By: Hokiefyd
I brought my '07 Corolla to the limiter once (believe it was 6,500 rpm) and it didn't buck or cut off or do anything dramatic. It simply stopped pulling and sat there at 6,500 rpm (manual transmission). I was impressed with how smooth it was.
My brother's '99 Corvette will bang off the rev limiter, but it's not all that violent. You get there quickly in it. 4.11 gears, Maggy-Lingenfelter supercharger, etc. You can hardly shift it fast enough to keep it off the limiter in 1st through 3rd gears.
Yup. The BMW just "stops" there. You feel it stop pulling.
I brought my '07 Corolla to the limiter once (believe it was 6,500 rpm) and it didn't buck or cut off or do anything dramatic. It simply stopped pulling and sat there at 6,500 rpm (manual transmission). I was impressed with how smooth it was.
My brother's '99 Corvette will bang off the rev limiter, but it's not all that violent. You get there quickly in it. 4.11 gears, Maggy-Lingenfelter supercharger, etc. You can hardly shift it fast enough to keep it off the limiter in 1st through 3rd gears.
Yup. The BMW just "stops" there. You feel it stop pulling.
I thought I had read somewhere (probably here) that occasional high RPM operation helped minimize ridges in the upper cylinder bore- the theory being that, at the top of the exhaust stroke, the tension on the rod bolts and the rod itself resulted in a tiny amount of 'stretch', causing the rings to travel a tiny bit higher up the bore than usual...
Also, what about heating up the intake valves enough to keep them clean (thinking DI here)? I'm assuming the most heat generated would be during a WOT hill climb at peak torque, right?
Also, what about heating up the intake valves enough to keep them clean (thinking DI here)? I'm assuming the most heat generated would be during a WOT hill climb at peak torque, right?
Originally Posted By: SteveSRT8
Note the redline on the Corvette is 6500 rpm, and I have seen completely stock original bottom ends on these cars with heavy mods run 7500 rpm with no apparent issues.
Yes, it is the stock cam, unported stock heads (although they are pretty darned good right from the factory), and the rest of the stock valvetrain which limits an LSx's effective, usable rev limits, NOT the bottom ends.
I've seen stock, unrebuilt, 150K mile bottom end LSxes safely rev past 8000 rpm with well chosen, correct top end components and cam.
Note the redline on the Corvette is 6500 rpm, and I have seen completely stock original bottom ends on these cars with heavy mods run 7500 rpm with no apparent issues.
Yes, it is the stock cam, unported stock heads (although they are pretty darned good right from the factory), and the rest of the stock valvetrain which limits an LSx's effective, usable rev limits, NOT the bottom ends.
I've seen stock, unrebuilt, 150K mile bottom end LSxes safely rev past 8000 rpm with well chosen, correct top end components and cam.
Originally Posted By: dailydriver
Originally Posted By: SteveSRT8
Note the redline on the Corvette is 6500 rpm, and I have seen completely stock original bottom ends on these cars with heavy mods run 7500 rpm with no apparent issues.
Yes, it is the stock cam, unported stock heads (although they are pretty darned good right from the factory), and the rest of the stock valvetrain which limits an LSx's effective, usable rev limits, NOT the bottom ends.
I've seen stock, unrebuilt, 150K mile bottom end LSxes rev past 8000 rpm with well chosen, correct top end components and cam.
ls1's dont count they were touched by the hand of God...
Originally Posted By: SteveSRT8
Note the redline on the Corvette is 6500 rpm, and I have seen completely stock original bottom ends on these cars with heavy mods run 7500 rpm with no apparent issues.
Yes, it is the stock cam, unported stock heads (although they are pretty darned good right from the factory), and the rest of the stock valvetrain which limits an LSx's effective, usable rev limits, NOT the bottom ends.
I've seen stock, unrebuilt, 150K mile bottom end LSxes rev past 8000 rpm with well chosen, correct top end components and cam.
ls1's dont count they were touched by the hand of God...
Last edited:
Originally Posted By: swirlparanoid
[/quote]ls1's dont count they were touched by the hand of God...
If you say so.
[/quote]ls1's dont count they were touched by the hand of God...
If you say so.
Originally Posted By: dailydriver
Originally Posted By: swirlparanoid
ls1's dont count they were touched by the hand of God...
If you say so.
[/quote] according to all the f-body boys thats always been the case lol at least it was when i had mine TOUCHED BY HAND OF GOD lol
Originally Posted By: swirlparanoid
ls1's dont count they were touched by the hand of God...
If you say so.
Last edited:
JHZR2
Staff member
Originally Posted By: Scott_Tucker
Originally Posted By: mechtech2
The highest cylinder pressures are at wide open throttle and mid/mid high RPM.
This is your torque peak - the most cylinder filling.
At high RPM, you have less filling, but at a higher rate.
The biggest stress from high RPM is the unloaded TDC of the exhaust stroke. The rod changes direction with high loads on it's bearing and pin.
^ This. The largest mechanical load on the engine is on the rod bolts at TDC on the exhaust stroke (they are in tension). On the exhaust stroke, there is no gas pressure in the cylinder to cushion the inertia of the rod and piston.
If you take your fist and put it to your chest and then punch outward as hard and far as you can, it's probably not going to hurt your arm. If you put a 10 lb dumbbell in your hand and do the same thing, your arm will probably pull out of it's socket. This is the same thing as the piston. Think of it as, the higher you rev the engine, the heavier that dumbbell becomes.
I agree, but the concept also leads to the fact that the faster you push that dumbell away, the farther that your arm will come out of the socket.
My point above was that the more ft/sec that the piston is moving the more elongation on parts that may occur, thus moving them in a range that wouldnt otherwise be touched at the ends of travel. This may cause cleaning of those sections, wear of those sections, or something negative.
Not sure what hitting a higher max pressure at the change direction point does that is good. You have highr chance of overcoming any oil films.
Moving the full range of motion though Id think is a good thing, no?
Originally Posted By: mechtech2
The highest cylinder pressures are at wide open throttle and mid/mid high RPM.
This is your torque peak - the most cylinder filling.
At high RPM, you have less filling, but at a higher rate.
The biggest stress from high RPM is the unloaded TDC of the exhaust stroke. The rod changes direction with high loads on it's bearing and pin.
^ This. The largest mechanical load on the engine is on the rod bolts at TDC on the exhaust stroke (they are in tension). On the exhaust stroke, there is no gas pressure in the cylinder to cushion the inertia of the rod and piston.
If you take your fist and put it to your chest and then punch outward as hard and far as you can, it's probably not going to hurt your arm. If you put a 10 lb dumbbell in your hand and do the same thing, your arm will probably pull out of it's socket. This is the same thing as the piston. Think of it as, the higher you rev the engine, the heavier that dumbbell becomes.
I agree, but the concept also leads to the fact that the faster you push that dumbell away, the farther that your arm will come out of the socket.
My point above was that the more ft/sec that the piston is moving the more elongation on parts that may occur, thus moving them in a range that wouldnt otherwise be touched at the ends of travel. This may cause cleaning of those sections, wear of those sections, or something negative.
Not sure what hitting a higher max pressure at the change direction point does that is good. You have highr chance of overcoming any oil films.
Moving the full range of motion though Id think is a good thing, no?
Since my '96 Contour Zetec 5 speed doesn't have a tach, sad to say, I can only estimate my redline by using the tire diameter, final drive ratio and tranny ratio in that gear. It gives me at what mph what redline is in that gear. It's not perfect but close. I've never hit the rev limiter but revved up the the "redline", by the calculations. I usually drive conservatively, great torgue in that engine, but do enjoy revving to my "redline" occasionally, it's fun. My car doesn't burn/use oil at all in 8,000 mile OCI's.
Whimsey
Whimsey
My question is: Is it bad to ATTEMPT to red line your car with a clutch that has the disc slip under high RPM?
JHZR2
Staff member
Why? It gets you to replace the clutch sooner!
Originally Posted By: JHZR2
Why? It gets you to replace the clutch sooner!
+1!, lol.
Why? It gets you to replace the clutch sooner!
+1!, lol.
on a high revving honda....no problems at all. my friend's rsx-s was redlined to 8.7k at least twice a day for the 2 years he owned it. the day he sold it, it sounded beautiful and only burned about 1/2 quart every 4-5k miles.
- Status
