Do I really need a lightened flywheel?

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chodjinn
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Post by chodjinn »

lol topcat.

Mark: I believe the standard flywheel is over 30lbs (33lbs?), and a 'standard' lightened one only loses about 7lbs IIRC.

I dunno what mine is, but even with the AP twin plate clutch and plates all bolted in, it is lighter than my original lightened flywheel lol! Probably sub 18lbs easy. I know some TVR racing flywheels are super light but not sure on the weight.

Either way, any engine/car will benefit from a lightened flywheel.


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Post by sidecar »

topcatproduction wrote:
sidecar wrote:
DrDeAtH wrote:also add in a couple of quid for a dictionary...


it is
ACCELERATION

Nobody bothers to correct another forum contributors spelling mistakes, it's not the point of a forum. (Unless it's a spelling forum). Maybe you'll learn that when you're less "wet behind the ears"
Sidecar you forgot your full stop at the end!!!

That's it, your all a bunch of GITS. :lol: :D :lol:
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Rossco
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Post by Rossco »

TopCat

The use of superfluous exclamation marks is frowned on in academic circles.
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topcatcustom
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Post by topcatcustom »

:(

Can we start a nuw area 4 inglish improovments then pleese??????????
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Post by topcatcustom »

However, I could not agree with you more Rossco, you "old bean" you. One should not feel it is acceptable to "slip down a notch" in this modern society we all live in these days by failing to ensure that ones spelling, punctuation and general English grammar is below standard.
Ravishing.

:wink:
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Rossco
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Post by Rossco »

Truly



As a matter of interest, I have a new Range Rover flywheel which one assumes could be lightened for the purposes aforementioned.
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Wotland
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Post by Wotland »

For the poor french native speaking man I am as long you don't use american english and their own phrasal verbs I am happy :lol:

So now for flywheel I know an compagny called Rakeway who can do custom steel/aluminium flywheels for Rover V8. They offer also lightened flywheels. http://www.rakeway.co.uk/flywheels,%20clutch.htm
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Post by ChrisJC »

Wotland wrote:For the poor french native speaking man I am as long you don't use american english and their own phrasal verbs I am happy :lol:
From an English speaking Englishman, I agree! :lol:

Chris.
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Ian Anderson
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Post by Ian Anderson »

How far do you want to go?

Decades ago i raced formula V - I know it is short 4 cylinders but it was fun and light. About 360kg and about 100 / 120 hp. from 1600cc.
So the engines were far from standard. The flywheel was down to about 3.5kg - and looked like good Swiss cheese with the number of holes in it!
Only enough metal left to hold the ringear in place and have a friction surface.

Offshoot of this was that idle suffered terribly - it would not idle less than 3500rpm (A little lower than a standard beetle reaches flat out) So then we removed all the idle crap from the carb and the main jet was modified with a 4.5mm drill! and it "idled" on the main jet.

Would it work around town - not in a million years!
Did I have trouble getting off the line? - NO Hold engine at 6000 and move foot sideways off the clutch pedal - worked very well and spun to 10 000 in about 5 feet, pulled straight to 2nd with no clutch and the wheels kept spinning so as not to bog the engine down. Again I think Mr Plod would be against this on the road!.

Now there is also a further problem with this in that the flywheel also acts as a heat sink for the friction of multiple applications, less metal and less heat sink. Higher temps and if there is a flaw in the lightened flywheel it will let go and parts exit the bellhousing ar a surprising rate - about the right area for it to remove your legs! (Again on the race scene I have seen a Mazda Rotary flywheel let go and spit out the clutch plate - he was on the first row of the grid - flag dropped Bang - car rolls forward and pulls off the track Rest of grid clear the stricken car before the clutch peices returned to earth - they had gone through the bell housing straight up through the slave cylinder through the bonnet and still stayed in the air 5 or 6 seconds - he was really lucky the blast went upwards!)

So after a rambling history lesson a lighter flywheel will increase the engine responsiveness but it is worthwhile getiing one done correctly and spending the extra cash.

Ian
Owner of an "On the Road" GT40 Replica by DAX powered by 3.9Hotwre Efi, worked over by DJ Motors. EFi Working but still does some kangaroo at low revs (Damn the speed limits) In to paint shop 18/03/08.
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Re: Do I really need a lightened flywheel?

Post by 14500rpm »

topcatproduction wrote:...its a SC 4l RV8 (maybe with a little nos shot) in a little mx5...
Pictures please!

I'll start...

Image

I have also been thinking about getting a lighter flywheel in the future but sometimes think I'd be better off saving my money for an LSx engine instead.
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Post by topcatcustom »

Wow- very neat! On close inspection I rekon its a killer on the brakes too.... literally unless you put a master cylinder on!!!!!
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Post by topcatcustom »

About keeping my eyes open for a clutch..... There's 2 on ebay! Twin plate AP racing so probably complete overkill for my little thing but can you guys tell me if the spline (1" 23no) fits rwd LT77 box? Also I know I'm being a bit tight but I'm guessing my lump wont break 3/400ft lbs torque and as they are big'uns what are the odds on the used one being ok?
http://search.ebay.co.uk/search/search. ... +v8+clutch

Or maybe they're completely unsuitable all together! Help?!
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Post by chodjinn »

Yes the splines on an LT77 are 1" 23no.

Those two clutches on bay of thieves are the same as the on I have. Looking at the new one, mine looks the same which makes me happy cus i got a bargain!

To be honest, you could get either. The 2nd hand one will prob need new clutch plates (Helix do sintered clutch plates for a little over £50 each - I think i paid £115 ish for mine posted last year - give 'em a ring very very helpful). So pro-rata it'd prob best to buy the new one! £200 is a good price - equivalent to what i paid for mine (I paid £400 inc. alu flywheel).

Bear in mind AP Racing are one of the best, and those clutches are circa £600 new (Think DJE and Sir Eales sells them off the top of my head). Dunno about supporting 560lb/ft, but they'll defo do over 400lb/ft.

hope that helps :D
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topcatcustom
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Post by topcatcustom »

:D

The only bad thing about nice gear like that is you have to hide it away in the deep dark depths of the car :(

oh what about release beaing- std or does it have to be shortened or something to fit twin plates?
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Post by chodjinn »

lol yeah, I wanted to mount my flywheel above the fireplace for all to see, but i kinda need it in the car!

As for clutch release bearing etc, everything should work from the standard LT77/Rover set up. I put my 'box back in a few months back and everything seemed fine, except the clutch badly needs a bleed as the master cylinder is nearly empty so its not actuating the slave, so i dunno if it works yet! Been a bit busy with other stuff recently!

I did, however, measure everything by comparing to an old clutch/flywheel combo and they seemed the same. Only issue I had was I couldn't use the ARP flywheel bolts as the holes were recessed in the flywheel, so had to order some custom ones from Burton Power, which actually came in cheaper than the ARPs!!!!
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