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Discussion Starter #1
I noticed the other day that my rev limiter has moved. I don't mean a little. I mean it moved out of state! :confused: If you see it please send it home. The only I have done recently is steeda pullies and T/A. Does anyone know if my Speedcal could have caused it to go bye bye. I want to make sure that it is not my fault before I go complaining to the dealership. Also what is a safe limit. Is it really 5750 in my GT like it was set at. My friend spins his Z28 way past the stock limiter.

Greg
 

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How do you know your going over it? The stock tach is WAY off, I remember my 5.0 wrapped passed 7k once, on the STOCK tach, my Autometer told a different story. I think 4.6 GTs are 6250 limited.
 

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Discussion Starter #3
well I have 373's, 275/40/17's, and a speedcal to compensate/adjust. That should make everything right right? Besides I just started noticing that it isnt there. I Used to could still hit the limiter but the other day I took it up past 6500 on a miss shift and thought I was going to spin a bearing or something
greg
 

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Ah! You didnt mention a missed shift. Rev limiters prevent motors from spinning themselves past the limit. You mechanically forced it hehe. Yes thats bad, and nothing can stop it.

Oh and yeah your gears and everything are fine, the computer only cares about RPMs, so even with an incorrect speedo it works. Your cars probably fine, but I wouldnt ride the limiter, I think stock 4.6s make max HP around 5400?

Be carefull:D
 

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Discussion Starter #5
??? so what you are saying is that a revlimiter wont work with it in nuetral??? thats basically what happened in effect. anyways I tried it again cruising down the road going about 45mph showing my buddy. I was in 4th, put the clutch in, hit the gas, and whamo over 6 grand,,still gettin used to the pullies man you gotta love em.
 

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Oh lol, we will get on the same level eventually. When you free rev the motor it tends to make the tach read really high for some reason, So ive noticed, I think your car is fine. You havent added a chip or anything?

Im allmost positive the 4.6s are limited at 6250 by the way.
 

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Discussion Starter #7
nope just stock computer but Im thinking about getting an eec-tuner of some sort if I can ever find out any info on it...boy that would be handy
Greg
 

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The rev limiter can only cut fuel. It is probably working, but you just cant tell. What is happening is that even if there is no fuel being added, in neutral the crank shaft has enough momentum to go past 6050 rpms. The limiter cannot physically stop the enigne, just stop it from accelerating. Try going past 6050 rpms with it in gear, I gaurantee that it will not go past the rev limiter.
 

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Discussion Starter #9
thanks slider and JF yall were right. I just took it for a spin and held in in first. I didn't know that you could free spin your engine and tach without the limiter coming into play. man you learn something everyday. huh . at least I can look like an idiot to yall and yall don't know me personally haha. second part of a topic was what is a safe revlimit in case I get a tune or something with damaging my goods?
 

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mystang00 said:
second part of a topic was what is a safe revlimit in case I get a tune or something with damaging my goods?
I don't know for sure, you will need to search the past forums, but I think a 2V can be taken up to around 6400 rpm before you get valve float.

Personally, I think the rev limiter is one of the most annoying things ever. I guess it makes sense in terms of covering their butts, but they could of atleast set it higher. Hey Ford, why don't you make an engine that makes peak power at almost 5500 rpms, but make sure that you don't let it rev pas 6000 :rolleyes: They got the all important PEAK number, though you really cannot make full use of it do to the damn rev limiter :mad: Would it of been that hard to engineer the car to rev up to 6300 rpms. I can't wait until I have enough money to buy a chip that can turn the darn thing off.

Sorry for the rant
 

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I thought that the rev limiter will kick in no matter if you are in gear or neutral. I hope this is right because i don't want to miss third gear once at the track and end up blowing the engine cause of it. I was told that the only time the rev limiter does not work is when you are downshifting. I also have heard of a few people hitting the rev limiter at the track right before their launches which means they are sitting there in neutral.
 

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Discussion Starter #12
next time you go out to your car you can see for yourself. I did both. with the clutch in I can hold it till it blows up (still not sure that that is normal) but in first gear it hit it.
 

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SR77 said:
I thought that the rev limiter will kick in no matter if you are in gear or neutral. I hope this is right because i don't want to miss third gear once at the track and end up blowing the engine cause of it. I was told that the only time the rev limiter does not work is when you are downshifting. I also have heard of a few people hitting the rev limiter at the track right before their launches which means they are sitting there in neutral.
The rev limiter does kick in when you are in neutral, the problem is that with no load on the engine it can go past the rev limiters rpm. The fuel has been cut to the engine so it can not accelerate any more, but the momentum of the crank and "stuff" allows the engine to keep going. It is already at some velocity, and with out a load on it, it takes a while for it to decelerate to a stop. Eventually, the crank will slow down and reach a peak rpm, but this could be as high as 7000 rpms so you need to be careful. If you just accidentally does this for a split second or so, you should not worry about it. just don't make it a habit.
 

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SliderGT said:
Personally, I think the rev limiter is one of the most annoying things ever. I guess it makes sense in terms of covering their butts, but they could of atleast set it higher. Hey Ford, why don't you make an engine that makes peak power at almost 5500 rpms, but make sure that you don't let it rev pas 6000 :rolleyes: They got the all important PEAK number, though you really cannot make full use of it do to the damn rev limiter :mad: Would it of been that hard to engineer the car to rev up to 6300 rpms. I can't wait until I have enough money to buy a chip that can turn the darn thing off.

Sorry for the rant
I gotta agree with you on the rev limiter settings for the 4.6 -- they are too low! The ideal shift points are ABOVE the rev limiter (especially for the 1-2 shift, which is quite a stretch) even for STOCK SOHC and DOHC motors. Most mods just make the situation worse, since the power peak almost always goes up as mods are done.

The irony is that the rev limit for the low-tech, pushrod 5.0L dinosaur was higher than the 4.6L SOHC -- 6250 rpm -- despite having a power peak of only 4200 rpm. (I NEVER hit the limiter in my 5.0, even when I tried to.) Also, I routinely spin my 383 Chevy stroker up to 6200, and that's with a relatively long 3.75" stroke, cast iron crank, stock 230K+ mile rods, pushrods, and an engine design that is 50 years old! Limiting a modern SOHC engine with a power peak of 5250 rpm to only 6050 rpm seems just a tad conservative.

Rant over....
 

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I think a distinction needs to be made here that there is a built in fuel shut off on the stock cars, not an ignition shut off. Many of us don't want the fuel shut off as long as there is ignition, so we kick the built in fuel shut off way up high with our chip, and then use our ignition boxes (like MSD) to kill the spark at what ever RPM we choose. This gives us a "rev limiter" that is adjustable.
 

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1) Don't trust the stock tach. It's way off.

2) Rev limiters are great, and I'm glad I have one.

3) The only way to overrev the engine is to downshift into too short of a gear at too high of a road speed.

4) OHC vs. OHV doesn't mean anything when it comes to rpm limit. Valvetrain mass, spring pressure, cam profile, etc. mean much more.

Just my $.02

Jeff
 

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The stock rev limiter really is a little low with modulars. You can rev past it by mistake with angular momentum in the crank. I once hit well past 7500 on a missed/not-paying-attention shift according to the stock tach on my 95GT (limited at 6300). Yup -scared the poop out of me. You'll almost never go past limit in gear, but if you are repeatedly revving it (higher,Higher, HIGHER - that sort of thing), or miss a shift and don't pay attention, you can really hurt the motor. All you need is for one spring to float and lose its valve keepers....valve drops into cylinder and goodbye motor.:evil:
 

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I never hit a rev limiter in my 2000 GT auto. The highest i reach til now are about
6400 rpm´s on the tach. This was at about 150 mph on the speedo and it is still
pulling but traffic stopped me.

As i read your posts i got the impression this is not the way it should be.

Ralf2
 
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