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Im thinking maybe less attention to rev limiters and much more attention to driver limits. It seems that some are exceeding their limits! and not for the first time. No need to show off and/or prove yourself, take it easy and build up to speed and fast times, geez from what I remember it was pretty hard to hit stuff at DECA. Its not that hard to stay on the tarmac. Just thought id mention this as I really enjoy DECAs, id hate for it to be canned because of someones irresponsible driving, id hate for a more serious accident to happen in future, so maybe more focus here.

I'm not sure if this is a direct dig at me, but if it is, I don't appreciate it. I've had my car since '03, it's seen a lot of hard driving and some track work and I'd never put a scratch on it prior to this. I don't think I was driving beyond my limits, I wasn't even giving it my all. The car did something I wasn't expecting and I couldn't regain control once it had. Shit happens.

There is plenty to hit if you go off; trees, poles and mounds of dirt don't have a habit of moving out of your way. It was a minor accident, I don't think it will effect any future events.

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Nothing wrong with limiters if that's your thing, but in a timed event (if you are aiming for a top time or a win) they are only going to cost you time.

We'll see how they go for times when results are out. :)

Dont forget that engines will lose RPM when load is put on it.

Syncronized Russ?

post-10715-1250723019_thumb.jpg

Nah I'll just wait for the engines/gearboxes to shit themselves, then I won't have to hear it :)

I'm just tyring to help with the timing side of things. Being my first DECA, I apologise for not knowing that no one actually cares about the times!

Funny you say that, because as much as people say they dont care about times and 'competition' we are constantly asked for them to be put up by lots of people. its like competition and fun cannot be in the same event... well it is.

As for the limiter comments, once you have done a few more decas and you are trying to find the smaller amounts of time you will realise that there are places where the limiter is going to get you that time. Changing gears is sometimes a waste and also makes it harder to get a good set up for the corner.

Then there is the excessive limiter users. they may not be maximising their speed but they make me happy :P

While I dislike excessive thrashing just for shits and giggles (it hurts me to watch it as much as do it myself), spending some time holding a gear high in the rev range can actually be advantageous as Ryan mentioned.

While you're changing gears you're not powering the wheels plus if you do change and put the car back into the middle of its torque curve you might find it now wants to break traction where as in the higher rpm of the lower gear where torque has dropped off the power delivery is easier to control (on tight corners like a skidpan)

Then, there is the other school of thought (I think it was Jim Richards who said this most notably) that taking a corner in a higher gear will often yield higher corner speeds and faster lap times as the car is more settled and you're riding the torque curve smoothy. This refers to race track stuff though where the turns are rarely as sharp as you might find on a skidpan battle.

Ultimately, drive to your style and preferences, there are a million ways to tackle any corner and million reasons why every way is right or wrong in someone's eyes.

While I'm not about to go thrash the hell out of my silvia because I'm on a budget, I'm not about to begrudge anyone who wants to have some fun frying tyres and put on a show for the rest of us.

One more...

The limiter is an electronic limit put in place to SAVE your engine...

i.e. not really gonna be the cause of any breakages...

(my car can rev to about 8500 safely... but i have the limiter set at 7000 because thats where the power ends... Therefore well below the safe limit)

Limiter bashing can cause undue pressure on things like oil pump gears, leading to a smashed pump... regardless of where the limiter is set.

dead pump @ 7,000rpm = dead motor

Russ, good to see you have the intercooler a polish >_<

Actually it's not your one. I picked up the PWR one cheap and it fitted better with piping and mounts so yours is still sitting in my garage. What do you want me to do with it? I can sell it for you if you like.

Limiter bashing can cause undue pressure on things like oil pump gears, leading to a smashed pump... regardless of where the limiter is set.

dead pump @ 7,000rpm = dead motor

Only on those dodgy RB26's Ash... >_<

Sarah: Great shots!

Yeh flog it off for me...please >_<

How much do you want for it?

By the way I love your avatar. i can just picture you in the swimming pool of your hotel on a sunny indian day on a tyre tube checking out the forums haha. Although it wouldn't be sunny now, it would be damn hot and humid!

My 2c...

runnining into the limiter for a couple of seconds if often quicker..

if you compare a couple of seconds of limiter to the time it takes you to change up from 2nd to 3rd then back down to 2nd for the corner...

Also if you are wheelspining on the limiter you aren't always hitting a brick wall... you can still be moving forwards...

You will notice this if you take off and hit the limiter then immediately change into 2nd gear.. your car will bog down and be off boost...

If you take off and bounce of the limiter until you can feel the wheelspin fading out then hitting second you can have a much better launch.

FYI my car doesn't make full boost until around 5000rpm...

One more...

The limiter is an electronic limit put in place to SAVE your engine...

i.e. not really gonna be the cause of any breakages...

(my car can rev to about 8500 safely... but i have the limiter set at 7000 because thats where the power ends... Therefore well below the safe limit)

That's what heel and toes are for. I've never wasted time changing down gears as it occurs during my braking. Changing up, if you can't do this in less than the amount of time people were spending on their rev limiters at DECA then you should consider an automatic. The only exception I would make to keeping it on the limiter (and even then I'd stay 500rpm off the limiter), is if you have something of a close cone slalom where continuing to accelerate won't benefit you at all.

I know turbo cars are difficult to launch to perfection, much more so than naturally aspirated, but there is a happy medium between bogging down in turbo lag and drowning the car in wheelspin. Hard to find but it's there.

Disagree strongly here - rev limiters are factory set to maintain a safe RPM below the threshold of the engine internals, yes. This does not mean you aren't doing damage to the engine. By all means test this theory with an open throttle in neutral until the thing blows if you don't think it will. The rev limiter is also just the lesser of two evils, i.e. a bit of engine component wear (e.g. oil pump) versus a conrod through the engine block. If your car isn't making full boost until 5000rpm for 212rkw then you have something of an engine/turbo mismatch.

We'll see how they go for times when results are out. >_<

Dont forget that engines will lose RPM when load is put on it.

Not forgetting, but I do maintain that I can dump my clutch at 3500rpm and take off with minimal wheelspin on full boost for first gear. It helps to balance this load with more throttle as you are releasing the clutch. Unless we have a 2 litre engine powering a 2.5 tonne vehicle, there is no load that will drop revs enough to justify hitting the rev limiter on a launch.

As for the limiter comments, once you have done a few more decas and you are trying to find the smaller amounts of time you will realise that there are places where the limiter is going to get you that time. Changing gears is sometimes a waste and also makes it harder to get a good set up for the corner.

Nothing but a very close cone slalom would have me considering the limiter for benefit, and even then I'd be staying clear of the thing. What's wrong with 500rpm before the limiter? Don't you people know your engines by the sound of them?

Then, there is the other school of thought (I think it was Jim Richards who said this most notably) that taking a corner in a higher gear will often yield higher corner speeds and faster lap times as the car is more settled and you're riding the torque curve smoothy. This refers to race track stuff though where the turns are rarely as sharp as you might find on a skidpan battle.

While I'm not about to go thrash the hell out of my silvia because I'm on a budget, I'm not about to begrudge anyone who wants to have some fun frying tyres and put on a show for the rest of us.

And Jim has it exactly right...the key to fast is smooth. Smooth launch, smooth gearshifts, smooth clutch work = fast time. If your car/engine is producing erratic/inconsistent behaviour, it costs you time. It's just logical.

Not having a go at anyone who wants to fry tyres. Like I said, and I can't say it enough, if you want to spin the wheels or bounce off the limiter for the fun of it and to give the people a show by all means do it. Contrary to what some people might think (after taking my opinion out of context), I actually like watching the odd burnout or wheelspin launch. I'm just stating how it is when it comes to times - how can breaking traction in a straight line possibly move you faster than maintaining perfect traction? All these cars would fail badly at quartermile and 0-100 times. The perfect launch is a tiny amount of wheelspin to let you know power was at the traction threshold. Anything more is wasted time and a clutch destroyer.

Limiter bashing can cause undue pressure on things like oil pump gears, leading to a smashed pump... regardless of where the limiter is set.

dead pump @ 7,000rpm = dead motor

Exactly right.

Yeah i cant wait for november, good thing its at the start of the month before i go os.

Got my eye of a few things before then too, rolling the rear guards, bit more low, camber arms for the rear, a swaybar for the front, R33 brakes up front and a roof spoiler just like AP's :)

Whether or not that happens thats another thing :D

Cant wait to see the results ...

Edited by philmak

We didn't as such meet but I remember speaking to you about the difference in price betwen 2.5" and 3" cooler piping at Autobarn hahaha. I was driving the silver R33 GTS-T :)

I cannot wait for November either. There's only one way to settle the disputes...afternoon untimed battles! :D

well there ya go... let us all be corrected...

Birdman has set the records straight...

For all of you who have any questions on how to drive fast

how much your engine can take and what sort of turbo setup you should have on your car..

Direct your questions towards the expert... Birds...

I would genuinely like to know where you get your knowledge from..

Are you a mechanic? or a racing car driver? or a pimply computer nerd?

All I can say mate is there are some people out there who have done 15+ DECA's

compared to your 1 or 2... i'd say they would have a better idea of what they are doing...

(Also let it be known that I have done only 2 DECA's, and don't consider my self to be a good driver at all)

But i am happy to be proven wrong... the results will be up soon...

P.S.

Hope I didn't crush everyone under the weight of my sarcasm.

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