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fine im using it as a reliable track car... who gives.

i dont think thats what he meant..

cf tailshaft is something either done last on high budget vehicles or not really done at all, simply because of the expense i guess. i never even considered one, and wouldnt unless i had to get a custom one made up for an engine conversion into something else.

i never thought they were only 2g though

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Given your desires, I'd probably say that instead of having a power target and aiming for maximum response, why not invert it?

Have a "response target" for the engine, and then just see how much power you can make while retaining that level of response within your budget? If you can only make 200rwkW, then that's still more than enough for most touges in your RWD car. If you manage to hit 230rwkW, then why detune it to get maybe a little more response that you didn't need anyway?

Food for thought.

LOL..here we go butting heads :P

the path to money spending is faster for some and slower for others. $15k for instance is chicken feed for owning a modified car.

If you spend $2,100 on a carbon fibre tailshaft ( I can put you in contact with the organisation that does them delivered for about that) , consider that some multiplate clutches can cost more. You want a nice set of forged rims as well? Thats going to cost you more by a factor of at least 2 and not give you the same sorts of benifits in the same sort of magnitude. Although it helps with suspension and brake associated areas as well and is worth doing too.

Also consider that the improvements to overall drive feel (thanks to reduced harmonics), accelleration and reduced wear on gearbox and diff all come without any penalty in on-going running, including accellerated engine (and everything else) wear costs, like more power does.

Why only 220rwkw? Why not?

The cars bits and peices will last longer at that level than More than 220rwkw means more attention and cost to get the power to the ground and make the car generally more reliable.

I am quite confident that if someone builds a car around a target 220rwkw and invests dollars in maximising engine response and the other important areas of braking and suspension etc, they can have a car that will be very nice to drive around town (with full interior) and make other peoples cars who are focused on power, look rather slow around a track.

This guy is on the right track, he needs a little more info about what he really wants to do and it's going to be a very good car he ends up with.

I hear what you are saying...but what im getting at is there is only small gains in looking to do what he wants. He is better off just sticking with the car he has with a few simple mods rather then trying to build a "response machine" :happy:

220rwkws is plenty of power if you can use it. But you dont need triple plate clutches that are over 2.1k for 220rwkws. You dont need cf tailshaft at 2.1k if you want a streetable, responsive streeter. You dont need to spend 4k on forged rims to have a nice responsive and streetable car.

It is overkill. Take a car with cf tailshaft, 4k forged rims, forged and built internals that are hopefully lighter then std. All thats been discussed here. Throw in some good pads, fluid and suspension and lets see how quick it is for a huge outlay of money.

Now take the same car, throw on a HKS 2530, with a Pfc, exhaust etc. Put the same pads, fluid and suspension in the car and you will have almost the same animal. Use R32 or R33 GTR rims for a lot less money. Use the std tail shaft and an Xtreme etc single plate clutch....

It makes no sense to go to all that trouble and expense...and im not saying there is something wrong with setting power goals to 220rwkws and concentrating on handling and braking. Im saying its silly to spend all that money on internals, cf tailshafts and 4k on rims etc when you only have 220rwkws goal, in the hope to get it to rev a little quicker. Go for ride in an RB25 car with a 2530. Going to the lengths suggested here would be like rolling a hand grenade into the trench next to you when you know the fly boys are about to drop a nuke on them. Sure you may get a bit more bang, but the nuke is going to do plenty on its own.

Anyway...im not one to tell ppl how to spend their coin, im as silly with my car as the next guy. Just pointing out he could be going down an expensive path which he doesnt see any value from

Hey, basically im happy to UP the power figure, but not at the sacrifice of response. (to an extent)

I havent spent anything YET. Im organising my funds and getting quotes.

All i want is something that when i put my foot down, the car goes forward rather than wheel spins, i dont want to wait 5 seconds for the turbo to kick in. I want a response/torque machine that will wreak havoc through the hills in the early hours.

(i wish i could make a 2 engin'd R34.. but budget doesnt allow.. that would be fun though)

Edited by illusiVe

Roy,

Doing the 'response mods' although initially expensive save you money in the long term. Whether you can afford to do them all or just a few. They are all 'good value' let me assure you as someone who has real experience in that area. All I can do is say you won't regret it. Gains being small is certainly not the case. I can tell you the difference between a car with an without them will be quite worth the money and the cost to achieve the same gain 'long term' is far greater in terms of power increase.

The $2.1k on a carbon fibre tail shaft is money well spent when you consider the benifits. The Mazda Rx8 and nissan 350z (track) and the Mines R34 GTR have that as a standard kit (Mines GTR aside), for very good reason. Don't really want to get into a long winded debate over that one. The cheapest Mines like mods you can probably do and one of the better ones in the spirit of the concept Mines were aiming at.

I'm certainly not in the business of building or prepping race cars, so to extra weight perhaps PM Sydneykid to get his thoughts?

Having said that here's a few rotational intertia real world examples I found to consider;

1) testing wheel weight on a WRX aceleration/deceleration.

The 17" rims are 11.5kg with Pirelli runflats. The 16" rims are 7.9kg with Azenis.

Here's the results:

All testing was done in the same location, 78 degrees ambient, same direction, 3 runs each

Same car.

17 11.5kg

-----

0-60mph = 7.37, 6.74, 6.85 seconds

60-0mph = 127, 125, 133 feet

16's 7.9kg

-----

0-60mph = 6.57, 6.67, 6.52 seconds

60-0mph = 115, 111, 113 feet

2) R32 GTR

Reduction of approx 2.5kg in flywheel , rolling accelleration this time.

Stock flywheel

60-90kmh 1.8 seconds

Light Flywheel

60-90kmh 1.7 seconds

3) Corvette Z06 Lightweight flywheel dyno timed accelleration to peak power. (I like these tests, people ought to do them more. In fact if your changing things on the car between dynos get your stopwatch out, it's too easy).

The runs were made in fourth gear from 2,000 rpm to 6,400 rpm (peak power). Or look at it another way speed could also be plotted across the axis instead. It wasn't in this case but, if someone wants to they could do some basic calcs.

Dyno 357.3 hp and 351.8 ft-lb

Stock clutch, flywheel pressure plate = 23.2kg

time to peak power = 14 sec

time to peak torque = 11 sec

New cltuch, light flywheel & pressure plate = 13kg

time to peak power = 11 seconds

time to peak torque = 9 sec

Some actual evidence to consider as opposed to the babble we all love :)

Oh there was my old R33 too.

The only change was to the flywheel in this comparsion. The ambient temps were both 32-33deg on the kwinana drag strip.

Factory flywheel

13.8@101mph 2.1 60ft

4.8kg Ogura flywheel (about 5kg reduced)

13.4@104mph 2.1 60ft

The R32 GTR rims are a great idea. Great forged rims at an excellent price second hand. They are very light.

What mods do you currently have? Id be going for HKS 2530 and RE55 tyres....and please dont crash into me or a family member when we are coming home late one night :)

Thats VERY hard to do unless you drive with no headlights on.

(and if ur in NSW)

OK so so far we can agree:

1) STOCK INTERCOOLER

2) STOCK/HI-FLOW TURBO

3)CARBON TAILSHAFT

4)LIGHTWEIGHT FLY WHEEL

5)CLUTCH SYSTEM - fan or whatever

6)LIGHT WEIGHT RIMS

7)INTERIOR

8)DIFF

9)ECU /TUNING

10)CAM GEARS

have i left anything out?

I would do the flywheel as well, but only when my clutch died. The lighter smaller diam wheels is another one...only run as big a wheel as you need. So no arguments there, im agreeing with you.

Its when ppl satrt talking lightened internals, cf tailshaft etc that they lose me.

LOL...my family home is in Richmond so i can say first hand there are some great roads out that way

I would change that too

1) HKS Type S fmic

2) HKS 2530 (STOCK/HI-FLOW TURBO is about 450hp vs the 320hp odd of the 2530. The 2530 will be far more responsive and net you around 220-230rwkws)

3) save your money for good tyres. ie $350-400 a corner

4)LIGHTWEIGHT FLY WHEEL

5)CLUTCH SYSTEM - fan or whatever

6)LIGHT WEIGHT RIMS

7)INTERIOR

8)DIFF

9)ECU /TUNING

10)CAM GEARS

I had a very long convo with SK one day in the street about weight reduction (not talking about response here). Basically he had just spent 7 or 8 grand on some weight reduction to gain 0.2 seconds a lap on a racetrack. His opinion was that for sprints, fun, club days, street, etc, it was not in the slightest bit worth it but on a 20 lap race 0.2 per lap is 4 seconds and that might be enough to win it.

very true abo bob/sk :P

i think its part of teh look which makes it fun though.. plus i love the excuse of not letting people grab rides 'sorry seats are taken' ;)

about the 2530 turbo.. thats 230KW.. is that engine figures or rear wheels?

Edited by illusiVe
very true abo bob/sk :no:

i think its part of teh look which makes it fun though.. plus i love the excuse of not letting people grab rides 'sorry seats are taken' :laugh:

about the 2530 turbo.. thats 230KW.. is that engine figures or rear wheels?

Rear wheels

I had a very long convo with SK one day in the street about weight reduction (not talking about response here). Basically he had just spent 7 or 8 grand on some weight reduction to gain 0.2 seconds a lap on a racetrack. His opinion was that for sprints, fun, club days, street, etc, it was not in the slightest bit worth it but on a 20 lap race 0.2 per lap is 4 seconds and that might be enough to win it.

i dont think that example applies here.. obviously a car thats primarly for the street its going to lose some luxeries with weight reduction, but if your only after performance and you track your car frequently enough, or even if your willing to have a street car without some niceties say air con, sound deadening, rear seats etc, then there is plenty to gain.

some of the silvia guys have bought down their weight to 1 tonne, from the stock 1250 kilos. if your running 230rwkw with a gt2530 in a stock silvia and you dropped your weight to 1 tonne, thats the equivalent of the stock weighted car being upgraded from the 230rwkw to ~290rwkw (based on power to weight ratios) with NO increase in lag or fuel consumption. the car will also be more nimble and the brakes would be under much less strain. of course the trade off is luxeries, and depends what you personally want out of your car, but theres no money to be spent, just ripping stuff out. bang for buck, you have to admit thats an extremely good (if not the best) performance upgrade for no dollars !

and being that you guys drive skylines/whales, im sure there is even more weight to be lost :(

i think sk's example was something along the lines of where they have this track car with a tube chassis and containing nothing a track car needed already, and losing a few kilos by say replacing the whole chassis with a newly designed one that weighed less (pure example)... sure this would cost alot for not much gain, but its not applicable to the road going cars we drive, theres definately gains to be made.

Edited by mokompri

Are those Silvias streetable at a ton? What's been done with the lightening?

I know of one NA S13 that's been stripped out of all "unnecessary" parts (no panel swaps), while still being moderately streetable, and its still over a ton. Considering the car's under 1200kg stock that's a good gain.

I don't know if weight reducing a Skyline will be much better. A Skyline has more sound dampening and creature comforts than a Silvia, but at the same time there's also a lot more car with bits you can't get rid of.

SK's also running a race car. He's probably hit the limits of what you can affordably strip / replace from the car already. Just like with powering up an engine, the first couple of kilowatts cost you peanuts...but at a certain point trying to make a few more reliable kilowatts is going to cost you a fortune.

yeap SK's example is a case of diminishing returns. maybe he changed alot of things for CF replacements, which is very costly indeed, who knows.

one of the 1 tonne examples i read about was actually on a US 240sx site which had a sr20 swap, and was pretty damn bare, but still street registered, engine bay was bare minimum too.

as for being streetable, well thats opinion. for me personally at that weight, no its not, but that just depends on the person and what they want out of their street car.

some will argue that as long as it has a drivers seat and is street registered, then its streetable :P if i had 2 cars then i wouldnt care about taking one to the bare bones for the ultimate driving experience. 290rwkw with the lag of a gt2530 and no increase in fuel consumption sounds pretty damn good :dry:

but in any case even if you lose 100 kilos, which isnt hard in a silvia, you will still have a much better 'performance' package.

EDIT: that n/a silvia isnt dumhed is it ? last i read from him his car was UNDER 1 tonne !

Edited by mokompri
EDIT: that n/a silvia isnt dumhed is it ? last i read from him his car was UNDER 1 tonne !

Who else would be stupid enough to rip out the air con, sound deadening, etc from his car and still call it "daily drivable"? :P

1025kg wet, I think is its current weight. He has added a full cage into the car as well, which is one of the few weight adding things in the car. There's quite a bit on his build-up here.

He's aiming for under a ton. If he can source fibreglass panels on the cheap, he should hit it without a problem.

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