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I am hoping to run but won't if I don't get my new clutch in by then. Since there will be so many SAU guys there I am definitely getting my act together to make it!

My new clutch/lightweight flywheel combo is going in next Friday (28th Mar) That'll give me enough time to bed it in & hopefully get used to it (i.e not stalling the car all the time :P ) Then bring on the 5th Apr & some 5000rpm launches :burnout:

Matt i hate to say it but the lighter the flywheel the more the car will bog. Its all about inertia and rotating mass. Sure it might rev slightly quicker but off the mark is everything and unless u have MEGA grunt i reckon u will go backwards. Time will tell but im pretty sure u shot yourself in the foot there. Good for mallala racing but thats about it. Not trying to be negative just stating a fact. Either way a good clutch is worth its weight in gold.

Brad,

Now you've gone & got me confused mate?:D

The reason I decided on the light weight f/wheel? - A couple of the guys in WA having had improvements over the 1/4 just from upgrading to a lighter FW (4.8kg / stock ~10kg).

rev210 (WA forum regular) has quite a bit of prior drag experience & he went from doing 13.8's to 13.4's just from changing to a 4.8kg FW. He backed these times up so it wasn't just driver improvement between the 2 runs.

I figured that as long as I keep the rev's up off the line (5k+) & get the car on boost ASAP I should see an improvement. Like you stated the key is not to bog on launch. The reason I've bogged on launch in the past have been from too few rev's. Up till now more rev's have resulted in either excessive w/spin (thanks to my stupidity for not doing a burnout) or clutch slip. Now I have the grip (RE540's) & soon will have a better clutch. A lot more rev's & the better clutch to cope with those rev's were all part of the plan.

I believe my car will get its best possible launch by w/spinning just slightly as I come off the line. The w/spin will help build boost ASAP. I would've thought the engines increased responsiveness (due to light FW) would help the boost build even quicker!? Rev's built faster ='s boost builds faster (less lag).

I've ordered the clutch & f/wheel but haven't actually paid for anything yet, so I can always cancel the f/wheel plans if it's a bad idea!? Hmmmm, I dunno'?

What do you think Brad? Anyone else?

I had to do something mate, it was time I progressed beyond a 13sec driver in a 12sec car :D

I wouldn't put it past ya' to get all those things fitted in time mate :D

It'd be nice if we both crack a 12sec pass next meet :(

Originally posted by BRUTE

geez Matt ya gona make it hard to catch ya now

hmmm  wonder if I can get some slicks a stally, 100shot of Noz

cam & heads done in time :bahaha:  

must be dreaming again :uh-huh:

G'day Greg. It's been a while mate! I guess the only good thing about 2mths away is extra $, $ that can be used for that HKS 25XX. How about a HKS GT-RS or 3037S?

Originally posted by grepin

Matt I am missing all the fun. I am 3wks away from coming home after just over 2mnths away. I hope there will be some action still. However heard winter will slow things down a bit. I will however be looking at a turbo maybe even a HKS 25??.

Good luck.

Well correct me if im wrong but Lightened flywheels r mainly for Fast reving high HP cars. Rotarys use this as they have no low end grunt to get revs up quick. Most propper cars for drags r auto to start with and have heavy Torque convertors with high stall to get the revs up. Lots of these have trans brakes etc. On a road car with smaller power figures the weight and momentum of the fly wheel carries it thru its dead strokes and gives it Kinetic energy that helps engine to overcome low speed engine revs. If u r gonna rev the ring outa it it may work ok but then u will have problems with wheelspin and breakages. Once the car is on boost the extra weight will help it get off the line quicker and wont affect the amount it picks up revs. Personaly i would say keep the standard weight flywheel unless u have 5.11 gears and 32 - 15 slicks. Although a quality clutch would be advised its still all about weight. Think of it this way, if u fired a gun with a bullet made of feathers it wouldnt hold its kinetic enegy for long. To be honest u would be better off buying better tyres and other things first. Personaly i would get a standard weight chrome molly flywheel and a quality clutch. If u realy wanna shave 10nths off your ET buy some better ratio diff gears so u r using all your ratios but will sacrifice top end on the open road. Hey how often do u sit on 200+kmh anyway?

So my advice is diff gears and tyres and that should prob shave at least half a second if not more. Tyres r the most important things for drag racing. Even putting skinnier tyres on the front like front runners might be worth 2 tenths. U would be suprised the rolling resistance on that sticky track. I could talk all night but that should open your eyes to a few new concepts. I doubt a lightened flywheel would do much at all to be honest as u r not increasing horsepower or torque by doing that. There r gains to be made other places before u go for the flywheel. Diff gears will make your car rev faster and therefore getting on boost faster and using all available ratios. The biggest killer in any car for drags is weight so if u wanna go fast start trimming bolt heads and pulling unwanted stuff out of the car.

Hope my advice enlightened u.

Have fun

Brad

Thanks for the input mate.

I guess at the end of the day I'm really not that serious about drag racing to go swapping diff gears (unless it breaks) plus I wanna stay within the HPI Street Drag rules (no slicks) I prefer to run the car 100% as is (no removing seats etc...) so I'll just have to do the best I can with these compromises :D

I see what you saying re the light flywheel. I might be better off just getting a very good clutch & leave it at that.

Cheers mate.

Matt, I have read on a couple of different forums that a lightened flywheel helps all round on cars like ours and the only slight drawback is some loss in inertial momentum which affects torque - but that is not such an issue in higher revs for our cars cos they pull very hard on boost all the way to redline. I am going to read back on this and other forums to make sure, but that's my understanding. As I think u know I am getting a lightened flywheel too.

I am sure guys on this forum have lightened flywheels .... either MattR or Clint32? Do you guys, or anyone else want enlighten us from a tried and proven aspect?

I know Brad, that for really torquey cars like yours and V8 etc that lightened flywheels are indeed a disadvantage as they don't keep making decent power in higher rev ranges - but I think for Skylines/Silvias we keep producing excellent power all the way up to 7k+ revs in worked motors due to the benefits of forced induction. And of course, as mentioned, the whole getting on boost quicker/easier is a massive advantage. Anyone else got some knowledge on this? I am not 100% sure ....

Thanks for the input dude. I've had a read on various forums over the weekend myself. It seems the faster rev's/quicker response far outweighs the inertia issue. I'm still not sure which way to go though?

Brad.. Mine doesn't bog down at all.

When Driving it away from the workshop for the first time I noticed heaps better response in first and second. Especially when off boost.

Taking off from a standing start was a lot easier and it was definately quicker in first and second with the chrome molly flyhweel.

It has been tried and tested. It is definately a worth while Matt.

Go the Lightened flywheel Matt.

Well I'm at Uni now so I'm broke.. Cars doing well though.

SO... I won't be running at AIR.. :)

Havn't been around here for a while.

Once again go the Flywheel Matt.

Just make sure you get a good brand.

Wouldn't want any vibrations when cruising at certian speeds.

Mine doesn't vibrate luckly.. But I picked it up for a $200 as a bit of a R&D Project. So I really couldn't pass it up.

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