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Wrong.  Thats like truck double clutching.  Not Racing double clutching... Doop!

OK Jamesh, :box: spell it out like I did, step by step and put down the time it takes to do each action. Then add it up. I know it's a strain but I am sure you can borrow a calculator.:dump:

I had an epiphany, how to prove the variable boost ratio gearbox :idea:

Put your car in second gear in the drive way, and push it. Count how many times the engine turns when the rear wheels turn once. Then push it really fast and count them again. If it's different, then you're right. :bahaha:

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Come on...this boy, uses eyesight, a passagener's reaction time with a stopwatch to achevie a 0 to 100 reading.

He likes playing the benchseat racer.....without even going to the track, he will alway over-rate his car's acheivements and his ability to drive will alway be better than those before him.......did his mother make a guess at his car's rear wheel kw's? He should fork out for a dyno-tune....but then the lack of ifing and what if's, is like throwing a wet blanket on a fire, for a BENCH RACER.

155 to 165 rwkw's because there is no way it would be running sweet and I'd lay money on the clutch being on it's way out.

Higher speed acheived.....in same gear....no variable diff ratio......higher boooost or whoosh for a more technical term (there's a laugh in there somewhere).

REASON.......the mind has been excited by the Whoosh....eyes are wide open....vision a blurr....concentrating on the road...quick glance at the speed and RPM....shit I think the RPM was this and the speed was this......is she gonna blow or is the clutch just slipping?????

Keep the thread going.....I love bench racing and laughing.

Phillip

Guest INASNT

Come on guys give him a break, this james guy is the next Einstein and his theorys on double clutching and variable speed diff ratios will transform the world as we know it and every car manufacturer in the past 200 years will realise they are all wrong and james is right!!!

:D :D :D

EUREKA!!!

I'VE WORKED IT OUT!!!

He goes faster on higher boost because if the extra jet thrust from his Super Glowey Neon LED Afterburner kitted exhaust tip. :flamed:

Sheesh, and you guys couldn't figure that out??? Call yourselves engineers??

:bs!:

jamesh3 , your ok mate.... dont take any notice form the SAU swine. :D

Hang around the forum and read up a bit more, enthusiasm is great... it seems you have a bit, but be careful who you get your facts (?) from

We are all occasionally the victims of others amusement :Oops: ....that said can you be sure im not on the list of ppl to catch up with when you go postal at an SAU meet :headshot: :D:D:D

man its just taken me over 30 mins to read this thread, omg its going off! not sure what jamesh3 is going on about gaining 20kph higher on higher boost, cause my 2nd gear always max's out at 100 regardless of 7psi boost or 15 psi. I know this cause i sometimes forget to change gears. Love the feeling of being under boost tooooo much!

anyways thats my 2 cents for this thread.

ok this thread is pretty funny i must admit

OK Jamesh....

umm mate..The "double clutching" you are referring to is not called double clutching (i have no idea what the proper terminology is called), but like you i have heard my friends and other people telling me that IS double clutching. I too thought that was double clutching at first until i did some research of myself and watched a crap load of those jap drifting vcds...and i realise now that my friends are pretty much unimformed about this issue.

Double clutching is not for the use for drag racing but more for drifting around corners as it involves the action of downhishifting. Here is a nice thread i found somewhere on my computer (dont ask me why i have this lol) which has a proper terminology and description on what exactly the correct terminology of double clutching is and why exactly many of the crazy jap drivers Heel toe all da way down mountains.

http://www.triumphspitfire.com/healtoe.html

Here is the article copy and pasted from this website.

Double Clutching

First of all let's deal with the "double declutching " issue. This is really only the British term for 'double clutching' and makes reference in some way I suppose, to the fact that it is usually a downshifting maneuver in disengaging the clutch. The first stage in a full 'heel and toe' gear change is the simple use of double clutching. On its own this is a fairly simple little dance of the toes and it goes like this:

1. You are driving along in your TR, MG or whatever in third gear for example, approaching a corner and preparing to shift to second. You brake with the left edge of the ball of your right foot as usual.

2. Depressing the clutch with your left foot the shift lever passes through neutral as this happens you release the clutch pedal out again half way, thus setting the mechanics of the clutch assembly in motion again.

3. Then fully depress the clutch to complete your shift into second.

That my friends is a double declutching. It might sound odd in print but is quite simple in action. Practice it in the driveway, with the engine off so you don't hit anything. The aim is to keep the engine and the clutch plates turning at the same speed for the moment when they engage themselves. Your car will thank you especially if you have an older vehicle that lacks effective synchromesh.

Heal and Toe

The next step is a true "Heel and Toe". Naturally it goes without saying that this does not really involve your heel and toe! The name is just to make it harder to understand! (Actually it stems from a rather odd set up in the old Ferraris where the clutch and the brake pedals were switched-but that's another matter.) The technique involves combining the double clutch method with a second technique that keeps the engine RPM at a level to match the next gear to be engaged.

Everyone has had the experience of changing down into a lower gear and having the engine forced into screaming high revolutions. The other thing that happens is that the weight of the car suddenly shifts forward due to the 'engine braking effect'. If you happen to be going into a corner this can be enough to lighten the rear end and send the tail out on a visit to the front end! Here's where the heel and toe technique comes in. Unless you have a third leg you have to brake and 'blip' the gas with your right foot. The tricky part is timing it all right and keeping the brake pressure steady while you do the 'blipping'. A note of warning here. If you practice this in your driveway as I suggested for double clutching, some of the newer cars will flood as a result of the gas pedal movement (yes! even without the engine running). So if this happens just go off and have a cup of tea and let things settle for a while before heading off to try it in motion. Here we go:

1. Begin the downshift as before, using the left edge of the right foot to brake. Depress the clutch and shift into neutral.

2. Now, as you're half releasing the clutch, swing (or rock) the right edge and heel of your brake foot over onto the gas pedal and squeeze it gently to bring up the engine RPM. With experience you'll get to know how much is enough.

3. Then depress the clutch and complete the shift into second. The plates should have been spinning from your double clutching and the engine RPM, which dropped while you were shifting, was brought back up to the level needed by the next gear ratio. Everything just slipped together without a murmur, and there was no forward weight shift or unwanted acceleration of the car. Swing your right foot fully on to the gas, and you're off down the straight.

Confused? I was too, and I "sort of know" how to do it. Actually the brain is not capable of doing this at all-the method has to leave the area of your brain and become a fluid physical skill. You drive along and your hands and feet do it all, without you really being aware of it; it's a great technique to master!

And mate there is nothing called racing double clutching....its like saying..im drag drifting if that makes any sense?

lol

i hope that article clarrifies what double clutch actually is, coz like 99.9% of the people here are right about it, and it seems that 0.01% which is you, thinks dat all the other 99.9% of us are wrong, and are only stirring you when we are not.

But anyways who cares whose right and whose wrong from the beginning, what matters is WHATS IS right in the end.

My 2c

Providing the rear tyres can hold on there's only 1 way to shift....

Flat change.. This requires you to basically hold WOT while quickly dipping the clutch as you slam the next gear.

I change near enough to a flat change, only slightly lift off the throttle.

Your are amusing jamesh3, do a bit of a search and read up a little.

I'm not sure if you are aware but there is also a web site called www.skylinesdownunder.com have a look around.

Great thread love it :D

But honestly Jamesh the 'ONLY' time you will ever (as I call it) 'SLIP' the clutch in a drag race is if:

1. You stuff the start and Bog down.

2. You are caught off guard / off Boost in a rolling start situation.

In everyother Drag racing situation there should be no need to practice this technique, as the gear ratios in your R33 are pretty well set up so as when you rev one gear out and change into the next you are on Boost in that gear already....why would you want to 'Slip' the clutch again?

Drifters use this techinique so as to unsettle the car in / approaching corners.

:D

At 10psi the cars accelerating much faster and coasts upto another 20kph higher because hes spending so much time playing with his clutch and effectively in neutral. Its just some extra momentum, once he finds the rev limitor in both 7psi and 10psi he'll (eventually) figure out its at the same speed/revs...

At 10psi the cars accelerating much faster and coasts upto another 20kph higher because hes spending so much time playing with his clutch and effectively in neutral.  Its just some extra momentum, once he finds the rev limitor in both 7psi and 10psi he'll (eventually) figure out its at the same speed/revs...

yeh your right *hit rev limit. 100km 2nd. Dam skylines are funn cars to rev the **** out of. As for "slipping" yeh better at lower revs to get boost up higher quicker. I hit 5.9 0-100 too on better surface less wheel spin lol. i know its atleast 6's now.

Owww as for the most entertaining post on double clutching in Aust... lol called slipping what i was talking about, why would other people i know call it double clutching too, and why would a multimillion dollar movie call it that do? Because in fact... it is pushing the the clutch twice, which would make it a double clutch... lol! i love this havoc and all these angry people... lmao

I rarely ever post on here but DAMN!

Jamesh dude, c'mon. I think you are forgetting that this is a SKYLINE forum, populated by many Skyline owners for years. The energy you have spent on attempts to rebuttle your claims is becoming more and more comical. For gods sake, please dont use Fast/Furious to support any arguments you have, ever.

At first i did think you were making valid attemps to support your claims, however, their are a few people on this forum whose advice/comments/knowledge hold a lot of weight on these boards. Please respect that. They have offered you their time to break down genuine facts and figures from many years of experience not just from hear say or "mates".

Sometimes dude its better just to let things go, take a step back and try to comprehend information, take it on board. Im sure many of us have learnt a shit load over time simply by browsing these forums.

If you are wondering why your comments are the subject of so much scrutiny, instead of suggesting post #'s for ppl to refer to for "double clutching" perhaps you need to read over the 3 pages of posts once again. An ignorant person is someone who dismisses the general consensus/views of others, despite facts/figures/knowledge in this case yourself.

I'm not trying to really get into you dude, moreso trying to express what other members of this forum have been trying to get across to you, a little less harshly.

Oh, Guys, take it easy on the bloke, hes havin a go, his not harming anyone.

Not that anything i say bares any significance.

Maybe someone could make this whole Thread a STICKY as a reference tool for how not present an argument.

Yeh i know m8. There have been some great posts, have learnt from people with great knowledge on cars. It is fair enough do let it die, i just call something out there a different name. I think its tomato, other tomarto. Ehhh.... Really we're talking about the same think i just call it "this", they call it "that" but the backbone of it is the same thing. My expansion on double clutchin has essentially been the same and i have had another’s post i've been correct on the details of it. Dont think i havent been reading whats been being posted, I have learnt from this thread, mainly just confirmations from people with great posts on how the shit really works! so theres no doubts. I think this could be a never ending war, i could go on more with examples of people using this double clutch term but wats the point. My point of saying my term is correct isnt getting through, and many others out there believe its what they've simply heard so lets keep it that way. Pretty hilarious really seeing all i wanted to get an estimate of what my cars putting out... one thing lead to another... funny shit anyways :( Call it what you want. I think i just wouldnt let my argument die because i have sources of the term, and what ya know, they do too...

Owww and you know what the funniest thing is... I Never said that 3psi boost will give you an extra 20km... Sure i was seeing it on my car, but from the very start, i only ever asked "why this was occurring", i never said, raise your car 3pound you'll get 20km/h lol, i knew there was something going on, exactly the reason to post... To find an answer. Although there were some great posts on how engines work, saying why it was impossible, other idiots were interpreting it as something else it never was, if it wasnt for these people there would have been more knowledge & answers posts on the subject, instead it was loads of crap. Responding to something which wasnt said. As for people who didnt read or interpret it right :bonk:

Hi jamesh, you stated 2 things that are so illogical, they have prompted the harsh responses you are getting. :argue:

Number 1

I would have to get into Mid 5's if i was running 10psi, No passengers, and Double Clutching.

This means you think pushing the clutch in and out twice (double) would decrease the 0 to 100 kph time. This is simply not true, it would slow your gearchange down and the engine would spend less time producing power. Think about how stupid double clutching on the up change is, you are doing ~7,000 rpm in first before you change into second. How can free revving the engine do anything? It is already at maximum boost producing rpm. :headspin:

Secondly a free revving engine produces less exhaust (at the same rpm) as an engine with load on it. So by free revving it you end up with LESS boost. Thus you claim for “faster” is doubly wrong, it is obviously slower and arguably results in less power. :wassup:

Number 2

The difference between 7 and 10 psi is huge. That extra 3 psi gives me 20km/h higher speed in 2nd gear.

This is simply IMPOSSIBLE, there is a solid connection between the wheels and the engine (in a manual car). So you can never have more speed for the same rpm in the same gear unless you change the gearbox or diff ratios or fit larger diameter tyres. Even then, if you don’t recalibrate your speedo, you won’t see any change. :Oops:

So there is only one thing for you to do, admit that you were

W-R-O-N-G ! :(

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