[Benjilafouine]

So I came on the subject with a friend about rev limiters vs speed limiters on automobiles. So far, I haven’t been able to find a clear answer or legislation document on this and will surely do more research.

My Focus is a Zetec 2003. A long long time ago when I was younger (like 20 years ago… I would never dare to do that again nowadays) I tried to see how fast my Focus could go. On a straight long remote road, I kept the gas pedal to the floor in fifth speed (manual transmission). At some point, I believe it was at around 155 km/h (about 97 mph), the engine cut off. It came back alive as soon as the car decreased speed.

Question: was this the result of a speed limiter or a rev limiter? Or both?

Unfortunately, on my Focus, the red line doesn’t not exist on my RPM gauge.

I am adding a note here: should I be in third gear and putting the gas pedal on the floor (which I certainly don’t want to try), would the engine cut at a certain RPM or it would let me burn the engine?

Thanks.

 

[Benjilafouine]

Think I have he answer: most likely my Focus has both a rev limiter and a speed limiter. Never made it to the second one… Seems like T tires are rated 118 mph and this was most likely what was on my car when I bought it. I prefer H tires because of better cornering (softer rubber I guess). I read elsewhere that basically my car should have been limited by speed at 118 mph but I never made it to that speed (I would have probably chickened out…).

 

[hEaT]

I always heard 108mph on the Zetec, but never tested that. But yeah you are correct, the car has both. The SVT speed limit is higher. From what I also recall, the Zetec rev limiter is at... 6750rpm? SVT 7200? There's no marking on the gauge, but that's where fuel cut is.

 

[Benjilafouine]

I always heard 108mph on the Zetec, but never tested that. But yeah you are correct, the car has both. The SVT speed limit is higher. From what I also recall, the Zetec rev limiter is at... 6750rpm? SVT 7200? There's no marking on the gauge, but that's where fuel cut is.

Friend of mine read 6,800 rpm somewhere. Most likely I hit the rev limiter back then. So, I can then assume that if I was to hit 6,800 RPM on a lower gear, the engine would also cut. Never happened to me in all these years.

I can share something that would require someone to go faster. A long time ago too, I was driving on the highway with my wife (can’t remember which car it was, maybe my “new then” Escort 1997 or the Focus 2003 but most likely the Escort) and there comes this guy in a pickup truck who clearly had something against me. Maybe I had passed him, really no clue.

He drove his pickup in the left lane and he tried to send us in the ditch. I slowed down and he kept wanting to throw us out the highway. Seeing no solution and looking at his truck, I was pretty sure that he couldn’t match my speed so as soon as I saw an opening I downshifted and hit the floor.

I came close to 100 mph and he couldn’t reach me anymore. He finally took the next exit and I slowed down. My heart was pounding and I wanted to call the police but since we were a night, I never read his license plate number. This is I think the only time of my life where speed actually saved me.

 

[hEaT]

Friend of mine read 6,800 rpm somewhere. Most likely I hit the rev limiter back then. So, I can then assume that if I was to hit 6,800 RPM on a lower gear, the engine would also cut. Never happened to me in all these years.

I can share something that would require someone to go faster. A long time ago too, I was driving on the highway with my wife (can’t remember which car it was, maybe my “new then” Escort 1997 or the Focus 2003 but most likely the Escort) and there comes this guy in a pickup truck who clearly had something against me. Maybe I had passed him, really no clue.

He drove his pickup in the left lane and he tried to send us in the ditch. I slowed down and he kept wanting to throw us out the highway. Seeing no solution and looking at his truck, I was pretty sure that he couldn’t match my speed so as soon as I saw an opening I downshifted and hit the floor.

I came close to 100 mph and he couldn’t reach me anymore. He finally took the next exit and I slowed down. My heart was pounding and I wanted to call the police but since we were a night, I never read his license plate number. This is I think the only time of my life where speed actually saved me.

I feel you on needing power and speed. So many newer cars now are just SLOW. Hybrids, crossovers and SUVs with little anemic 1.6l engines, etc. Having the RS, it's nice to be able to downshift and get by/around dangerous situations vs only being able to brake for them.

And yeah, regardless of gear 6750/6800 is where the engine will stop revving. Zetec power/torque starts to drop off around 5500 so there's no point in going that high anyway (unless you'll be slowing down and shift time would be worse, like on a track or autox).

 

[Benjilafouine]

I feel you on needing power and speed. So many newer cars now are just SLOW. Hybrids, crossovers and SUVs with little anemic 1.6l engines, etc. Having the RS, it's nice to be able to downshift and get by/around dangerous situations vs only being able to brake for them.

And yeah, regardless of gear 6750/6800 is where the engine will stop revving. Zetec power/torque starts to drop off around 5500 so there's no point in going that high anyway (unless you'll be slowing down and shift time would be worse, like on a track or autox).

My 2014 Escape with its 240 HP is really not bad too! I selected a good package and it came with H rated tires. Never hit its max speed.

 

[hEaT]

My 2014 Escape with its 240 HP is really not bad too! I selected a good package and it came with H rated tires. Never hit its max speed.

Yea those aren't too bad - Same motor as the Focus ST.

 

[WoodmanMN]

Assuming you have a tachometer, what RPM were you at when you cut power?

If you were well below the higher end of the rev range, you most likely hit a speed limiter programmed into the ECU.
My 97 Thunderbird had one due to the amount of wobble in the two piece driveshaft. An ECU tune and one pice aluminum shaft cured that issue.

A rev limiter is often used to prevent you from going beyond redline in lower gears (5th is an Overdrive gear. Your car doesn't have enough horsepower to max it out to the top of the rev range, you'd theoretically go faster in 4th gear without a speed limiter), it's what you hear making the engine misfire in the movies where they rev it in neutral.

I do not know if Ford put a rev limiter in the ECU. The speed limiter is for safety as you mentioned before, either due to the limitations of the stock tires, or other limitations such as my two piece drive shaft in my Thunderbird.

 

[Benjilafouine]

That was 20 years ago. I may have been in fourth also, not necessarily in fifth. From what I remember however, the RPMs were high but I was more looking at the road (no wonder why).

I read other posts here and information on the web and it should have gone faster than 97 mph based on the tires limitation.

I will certainly not retry that being much older than I was at the time but the questioning started with a friend who thought I hit the speed limiter. After doing some research, we determined that the speed limiter should have been set at 118 mph according to the tires so we’re wondering why I even didn’t reach 100. Here’s an older link:

top speed limiter

How do you take this off.

www.focusfanatics.com

 

[radius6]

Like the OP, when I was young I used to be more careless, my daily drive included a deserted 8km mostly straight stretch and I used to give it the beans.

I used to hit 120mph in my 2003 Focus Ghia 2.0 Zetec
Not sure if ratios on our models were different, it was certainly a down slope, not pronounced, but not flat either.

I could routinely hit 110/115 in a flatter surface. Never hit a limiter on 5th either but it was so long I didn't have any power left to hit it. I remember hitting 190km/h in 4th.
Now I rarely see over 60mph/100kmh

Edit: https://www.ultimatespecs.com/car-specs/Ford/42506/Ford-Focus-1-Sedan-20-Ghia.html
according to this top speed should be a smidge over 200km/h which seems correct for me, not that you can really hit that unless you have a lot of space.

Perhaps US spec cars had a different limiter?

 

[Benjilafouine]

Like the OP, when I was young I used to be more careless, my daily drive included a deserted 8km mostly straight stretch and I used to give it the beans.

I used to hit 120mph in my 2003 Focus Ghia 2.0 Zetec
Not sure if ratios on our models were different, it was certainly a down slope, not pronounced, but not flat either.

I could routinely hit 110/115 in a flatter surface. Never hit a limiter on 5th either but it was so long I didn't have any power left to hit it. I remember hitting 190km/h in 4th.
Now I rarely see over 60mph/100kmh

Edit: https://www.ultimatespecs.com/car-specs/Ford/42506/Ford-Focus-1-Sedan-20-Ghia.html
according to this top speed should be a smidge over 200km/h which seems correct for me, not that you can really hit that unless you have a lot of space.

Perhaps US spec cars had a different limiter?

Could be but at 200 km/h, it seems to be in line with the tires rating speed limiter (if any) given also a small error margin although I never got there myself. What’s interesting is that you could get to 190 km/h (118 mph) in fourth gear. I suppose you can’t tell at how many RPMs you were flying! If you didn’t bounce the rev limiter it means that even in fourth gear, you can reach the vehicle top speed without triggering something.

I drove through that stretch of road that I used 20 years ago just last week and realized that there is a little slope going up at the end of the stretch. Maybe this is why I obviously hit some kind of limiter. I never drove the car that fast since then and it is still in very good condition, only 70k miles on it.

 

[radius6]

I wouldn't know for sure, but I found an argentinian review (my car is argentinian) of the ZETEC 2.0

Ford Focus 2.0 Ghia 5p

Road Test - Prueba Ford Focus 2.0 Ghia. Caracteristicas técnicas. Revista Auto Test

www.testdelayer.com.ar

They claim 182.6km/h top speed in 4th, which is 114mph
They also claim 200km/h top speed at 5400rpm in 5th, but I can tell you for sure it can do more, you just need space and you have a lot of tach left from 5400rpm.
That said, different regions different gearing, different wheels, all of that can make a difference

Final ratio: 4.06:1
1st 3.42:1
2nd 2.14:1
3rd 1.45:1
4th 1.03:1
5th 0.77:1

 

[Benjilafouine]

I wouldn't know for sure, but I found an argentinian review (my car is argentinian) of the ZETEC 2.0

Ford Focus 2.0 Ghia 5p

Road Test - Prueba Ford Focus 2.0 Ghia. Caracteristicas técnicas. Revista Auto Test

www.testdelayer.com.ar

They claim 182.6km/h top speed in 4th, which is 114mph
They also claim 200km/h top speed at 5400rpm in 5th, but I can tell you for sure it can do more, you just need space and you have a lot of tach left from 5400rpm.
That said, different regions different gearing, different wheels, all of that can make a difference

Final ratio: 4.06:1
1st 3.42:1
2nd 2.14:1
3rd 1.45:1
4th 1.03:1
5th 0.77:1

That’s nice. I’m almost tempted to try again but I’ll take your numbers instead! I’m too old for that now!

When I bought that car I was 39 years old (after someone hit me badly from behind). I am now going on 60 years old. More to that, the accident from 2003 left me very damaged and I don’t think I will get to live very old. 🥲

 

[radius6]

Yeah no reason to go and risk it like that, back then we didn't really have speed limits over here, now we do... I wouldn't do it, I still enjoy going quickly within the limits.

I have had my focus since 2003, I'm 41 now, I still enjoy it a lot
I never modified it until 4 years ago, when my engine died and I couldn't let my first car go like that, so a rebuild later it's very healthy, pushing over 120hp to the wheels, which is great considering were at 9000ft above sea level

No longer my daily driver but I still take care of it

 

[Benjilafouine]

Yeah no reason to go and risk it like that, back then we didn't really have speed limits over here, now we do... I wouldn't do it, I still enjoy going quickly within the limits.

I have had my focus since 2003, I'm 41 now, I still enjoy it a lot
I never modified it until 4 years ago, when my engine died and I couldn't let my first car go like that, so a rebuild later it's very healthy, pushing over 120hp to the wheels, which is great considering were at 9000ft above sea level

View attachment 316973

No longer my daily driver but I still take care of it

I’m happy for you that you were able to keep your first car and still enjoy it today!

My first (used) car was a Chevrolet Chevette and it didn’t make sense to keep it (someone else worn it before me). Then I had four more cars but always some things happened that I didn’t want to keep them (theft, paint issues, car not worth keeping and then the smash that almost sent me in a wheelchair).

The first car that nothing to it is my Focus (knock on wood). I’m also happy that I had selected the Sport package. Still looks great, with original paint. Not driving in winter with for many years already.

 

[hEaT]

The European cars didn't have the same speed limiter as the cars in North America from what I recall.

 

[Benjilafouine]

The European cars didn't have the same speed limiter as the cars in North America from what I recall.

Because of the tires size? Speed limits are generally higher in Europe. I drove in France before they installed all these speed traps and with speed limits at 130 kph, people were literally driving 160 ((100 mph). I did it on a Renault and never hit any limiter. These were my younger days… It was on my honeymoon trip…

 

[hEaT]

Because of the tires size? Speed limits are generally higher in Europe. I drove in France before they installed all these speed traps and with speed limits at 130 kph, people were literally driving 160 ((100 mph). I did it on a Renault and never hit any limiter. These were my younger days… It was on my honeymoon trip…

Probably not, it's more so country regulations. What were the OEM tires on these cars? I think H rated on the 15s, so that still good for 130mph.

 

[Benjilafouine]

Probably not, it's more so country regulations. What were the OEM tires on these cars? I think H rated on the 15s, so that still good for 130mph.

It was the Renault Megane, a step up from the Renault Clio. After all, it was a honeymoon trip! That was in 1997, a long time ago. By some extreme bad luck, my wife passed away in January. She filmed a stretch of road where we were actually going at 100 mph and surprisingly, we were not the fastest on the road. Some people would flash their high beams for me to let them pass me.

 

[radius6]

The European cars didn't have the same speed limiter as the cars in North America from what I recall.

My original tires were pirelli p4000, H rated 195/60R15