Spirited driving fail? Over rev?

[steve99]

Often damage to engines is not apparent immediately and may take months or years to result in failure or other visible/audible problems.

The factory engineers set an rpm limit of 7400. This will have some degree of safety margin and likely designed so that engines will last considerable periods of time and kilometers with very small numbers of failures (at stock power levels) so the manufacturer does not get a bad name because of excessive numbers of engines failures, you always going to get some failures.

If you rev past these limits by altering tune or by mechanically over revving engine during downshifts (stock internals) then its likely going to result in a higher chance of failure at some point. How much difference it makes well who knows depend on amount of over rev , how often you do it, oils , luck whatever.

Abnormal driving techniques like holding on the rpm limit for long periods, or even tracking cars or even driving them hard on roads will in general shorten the life of all mechanical components in the car.

These cars are not race cars they just a sporty car, their only designed for normal road use and a little "sporty' driving. Like most other "road" car take them to the track and oil temps become excessive quickly , brakes fade and in general most mechanical components on the car will show increased or abnormal wear rates.

If you do it accept the risk or dont do it.

[wparsons]

Originally Posted by Detroiter

Why would the limiter have nothing to do with it? It is literally only there to limit the RPM's. Downshift into wrong gear, Let of clutch which doesn't grab instantly(it's fast but not instant), engine is brought up to the RPM needed for the gear but the rev limiter tries to stop the engine from going bast the point resulting in very harsh engine braking. Then it's a fight for what gives first either the engine pushing past the fuel cut or the rear tires giving up traction. Especially on a cold day with summer tires the sudden onset of resistance could make the tires break loose.

Also I want to stress that I have NEVER done this I rev match and heel toe downshift every time I drive therefore I am very aware of how much rpm change happens between each gearing and know how it feels going into each gear. If you meant that towards OP or others then yes making sure you know the shifter and gearing is very important before downshifting.

Fuel cut doesn't matter on deceleration... most modern cars run almost no fuel (or truly none) at all on deceleration in gear.

Typically rev limiters aren't fuel cuts either, they're spark cut/retard. Fuel cut typically only happens when the ECU can't figure out what to do, so it shuts fuel and spark down. In a drive by wire car it'll close the throttle plate before it resorts to that though.

There is nothing the ECU can do if you downshift into 2nd instead of 4th to save the engine from over revving.

[Detroiter]

Originally Posted by wparsons

Fuel cut doesn't matter on deceleration... most modern cars run almost no fuel (or truly none) at all on deceleration in gear.

Typically rev limiters aren't fuel cuts either, they're spark cut/retard. Fuel cut typically only happens when the ECU can't figure out what to do, so it shuts fuel and spark down. In a drive by wire car it'll close the throttle plate before it resorts to that though.

There is nothing the ECU can do if you downshift into 2nd instead of 4th to save the engine from over revving.

I honestly don't know how I didn't think of that when I was commenting It makes sense to me now, but I never thought it would really be able to save people except in a very minor case of over rev which now I'm assuming it's just the sudden lash of resistance from going into gear that can break the tires loose in some cases.

Now that I know the true way maybe I too can have some of Tcoats cookies

[TommyW]

Originally Posted by Detroiter

I honestly don't know how I didn't think of that when I was commenting It makes sense to me now, but I never thought it would really be able to save people except in a very minor case of over rev which now I'm assuming it's just the sudden lash of resistance from going into gear that can break the tires loose in some cases.

Now that I know the true way maybe I too can have some of Tcoats cookies

Naw. You gotta EARN your cookies....

[stevesnj]

Originally Posted by steve99

Thousands of guys track these cars with stock engine and rev them from 5000- redline consistently for entire tract or autocross session s. And their are very few that blow up.

I track my car and hit the limiter sometime. The car is advertised as a car to take it to the track so I am . confident it can handle it.

[Tcoat]

Originally Posted by steve99

Often damage to engines is not apparent immediately and may take months or years to result in failure or other visible/audible problems.

The factory engineers set an rpm limit of 7400. This will have some degree of safety margin and likely designed so that engines will last considerable periods of time and kilometers with very small numbers of failures (at stock power levels) so the manufacturer does not get a bad name because of excessive numbers of engines failures, you always going to get some failures.

If you rev past these limits by altering tune or by mechanically over revving engine during downshifts (stock internals) then its likely going to result in a higher chance of failure at some point. How much difference it makes well who knows depend on amount of over rev , how often you do it, oils , luck whatever.

Abnormal driving techniques like holding on the rpm limit for long periods, or even tracking cars or even driving them hard on roads will in general shorten the life of all mechanical components in the car.

These cars are not race cars they just a sporty car, their only designed for normal road use and a little "sporty' driving. Like most other "road" car take them to the track and oil temps become excessive quickly , brakes fade and in general most mechanical components on the car will show increased or abnormal wear rates.

If you do it accept the risk or dont do it.

This ^ OH god, so much this!

Originally Posted by stevesnj

I track my car and hit the limiter sometime. The car is advertised as a car to take it to the track so I am . confident it can handle it.

Nothing wrong with bouncing off the limiter once in a while but like Steve says hanging it there or exceeding it will increase wear. This is not a possibility it is a firm will. Still nothing wrong with doing even that though, as long as you understand that there will be accelerated wear. That wear may only mean that the car lasts 399,999K instead of 400,000K but it still means a reduction. It is advertised as a road car that can be tracked not as a car made specifically for the track. Those are two totally different things.

[Tcoat]

Originally Posted by wparsons

There is nothing the ECU can do if you downshift into 2nd instead of 4th to save the engine from over revving.

It could yell at you!

[stevesnj]

Originally Posted by Tcoat

It is advertised as a road car that can be tracked not as a car made specifically for the track. Those are two totally different things.

Well aware.

[Tcoat]

Originally Posted by stevesnj

Well aware.

Figured you were but others read as well.

[Ultramaroon]

Originally Posted by Tcoat

It could yell at you!

[nikitopo]

I would say it is a car build to be tracked, but at the same time has some deficiencies because it had to be road legal. There were certain people that worked hard on race tracks trying to refine this product. It is at least naïve to make statements that the car was designed for a little sporty driving, like most other road cars.

[Sportsguy83]

Originally Posted by nikitopo

I would say it is a car build to be tracked, but at the same time has some deficiencies because it had to be road legal. There were certain people that worked hard on race tracks trying to refine this product. It is at least naïve to make statements that the car was designed for a little sporty driving, like most other road cars.

It's definitely not a car built for the track, it's a sporty cheap car.

Prepping it for track (better tires, better brakes, addressing oil and fuel starvation, factory oil cooler) were not compromises to make the car "road legal". They are compromises made, among other things, to keep it as a cheap, sporty, lightweight car.

[nikitopo]

Originally Posted by Sportsguy83

It's definitely not a car built for the track, it's a sporty cheap car.

Prepping it for track (better tires, better brakes, addressing oil and fuel starvation, factory oil cooler) were not compromises to make the car "road legal". They are compromises made, among other things, to keep it as a cheap, sporty, lightweight car.

So you were expecting to come with track tires and track pads? Are you serious? Oil cooler could not be installed, because it would not be road legal with oil lines in front of the bumper. It is not a time attack race car, but it can run endurance races with minimal changes and a stock engine. How many road "sporty" cars can do this?

[Sportsguy83]

Originally Posted by nikitopo

So you were expecting to come with track tires and track pads? Are you serious? Oil cooler could not be installed, because it would not be road legal with oil lines in front of the bumper. It is not a time attack race car, but it can run endurance races with minimal changes and a stock engine. How many road "sporty" cars can do this?

I wasn't expecting anything, I'm just calling the car what it is. Oil cooler can definitely be installed from factory, like it is on many other cars, it doesn't need to be installed in the front bumper, car manufacturers have very creative engineers to get it done. Also it doesn't need to have track only tire (non DOT tires i.e. illegal) to be a track built car. It can also have aggressive brakes that are suitable for the street but work in the track for 99% of people.

Not knocking on the car, it's a lot of "driver" car for the money, handles beautiful, looks good, lightweight like very few nowadays. But calling it a "track built" car is a stretch .