Go Light Weight

[renxun]

front wheel drive cars DO tend to understeer to compare with most rwd car

 

[whatdamn]

starscream,
it takes a lot of work to design a proper cross-member. not only do the designers take into account static loading but due to the nature of its use, dynamic testing is also conducted via computer simulations which i can tell you, is computationally very expensive and time consuming. also, let's say you skip these steps and just fabricate a one-off cross-member, a small accident MIGHT prove catastrophic because designers also take into account crash dynamics of that particular component. take it from me, i'm currently doing my thesis which is to redesign the front and rear lower control arm of a proton putra and it's not as easy as i thought it would be.

i'd consider these safety critical items in a vehicle because failure of such parts would have a huge effect on vehicle handling (ie. if something like that breaks/fails, you can't steer your car properly!).

bottom line, do things safe yeah?

 

[GT_AUTO]

not to question your opinion, brother. but those grammes, they really add up to quite a lot!

that's how superbikes are lightened over the years what?

engineers removes a gram here n there.
waisted bolts, drilled calipers, magnesium and carbon fibre instead of alloy or aluminium, miniscule stuff that we ignored.

we haven't talk about F1 weight saving techniques yet, have we?
like how they weigh the car before and after paint, how much weight the stickers are n stuff like that?

waaa....bro,u talk until F1 ar???well,what u said is true bro but we're
talking about street car mar.how much u can save for 4 tyres?u willing
meh to bring a scale to a tyre shop just to weight the tyre 1 by 1???
:hmmmm:.

 

[FVel]

starscream,
like what renxun said. i think you should go no larger than 14" wheels if you're wira is the 1.3/1.5 model and no larger than 15" for the 1.6 or 1.8 model. you could check out the volk ce28n wheels as they seem to be the lightest 15" wheels available and next in line is the desmond evo regamaster.

Good choices for 14" wheels are about as abundant as dragon's teeth. Do you have any opinions of a good 14" wheel with 4-hole PCD 114.3 and an offset of 38 or 40 ?

 

[renxun]

not neccesary bigger rims will be heavier than small rim....its the brand n type that matter... for a small budget why not try to source for S13 original rim..? its only around 500-600 inclusive of tyre... 17" some more ..and its a 4hole 114.3 pcd

 

[whatdamn]

fvel,
checkout WHEELWEIGHTS.NET

 

[starscream]

starscream,
it takes a lot of work to design a proper cross-member. not only do the designers take into account static loading but due to the nature of its use, dynamic testing is also conducted via computer simulations which i can tell you, is computationally very expensive and time consuming. also, let's say you skip these steps and just fabricate a one-off cross-member, a small accident MIGHT prove catastrophic because designers also take into account crash dynamics of that particular component. take it from me, i'm currently doing my thesis which is to redesign the front and rear lower control arm of a proton putra and it's not as easy as i thought it would be.

i'd consider these safety critical items in a vehicle because failure of such parts would have a huge effect on vehicle handling (ie. if something like that breaks/fails, you can't steer your car properly!).

bottom line, do things safe yeah?

Thanks man...my greatest respect to you for sharing...i been hoping to meet ppl whom actually have good knowledge like you...oh your actually in automotive engineering? mind to share what is the restriction you find in designing the lower arm? like the kinds of load & what is the material toloerance towards the load.. i compare the lower arm of proton (bend mild steel welded) with Evo (fully casted one piece hard steel) i think there is a significant difference in term of durability...
i see the wira cross member as a cheap set up by using thicker mild steel, bended & weld rather simply...i thought i can do better...but i need to learn more before i do...i believe by following the weld area, bolts area, n use a tube design & it would actually be safe & light enough..well i don't know... Check this site out http://www.amsperformance.com they got fabricated light weight center member..

 

[whatdamn]

starscream,
i'm actually a 4th year mechanical engineering student. i can't disclose the details of my study because it's considered 'monash intellectual property' but i can give you the gist of it though.

as far as what you said, "wira cross member as a cheap set up by using thicker mild steel, bended & weld rather simply", you have the wrong mentality because it is really difficult to produce a CAD for complex stamped sheet metal like those you find on lower arms and such and not just on our protons but also other major manufacturers as well. the evo LCA is not steel and is in fact cast aluminum alloy (how many % aluminum i have no idea). same as the subaru impreza wrx STi's. both offer reasonable amounts of durability however the evo LCA is definitely lighter in comparison to the mild steel variant. how much load can the both of them take? we (I) won't know for sure unless someone can post their finite element analysis (FEA) or ADAMS simulation results here...which i doubt anyone has access or will post because it's property to those respective companies.

a representative engineer from proton came 3 weeks ago to give the students some insight to what engineering has taken place in proton since the waja phase and it's quite impressive really. they have been doing FEA for different load cases and also shape optimization to reduce 'hot-spots' (ie. areas with high concentration of loads) whereby they add material to those hot-spots and reduce material at other less affected spots and run their simulations till they get an agreed upon result.

one funny/interesting FEA performed was a cabriolet version of the satria neo that was toy'd around by proton's engineers. but yeah, they are doing work contrary to popular belief.

i suggest to all that we should learn the basics before intending on reinventing the wheel. keep things simple first then once you can't go any further should you only attempt to fabricate/design new components for your ride. :)

 

[boyzone]

bro, for the daily basic use, just follow below few items are good enough already.
1. no power window.
2. light weight wind screen
3. small size battery
4. no spare tyre for the city drive.
5. look for GSR disc plate ( tinner compare with mivec )
6. use 4G91 air con compressor.
7. no ICE inside , just remain CD player with stock speaker.
8. light weight sport seat.
9. light weight sport rim with high performance tyre.
10. Performance clutch set and lighten flywheel.
11. Light weight tower bar and lower arm bar.
12. Single layer radiator and half face air con condensor.
13. After market 421.

As I mentioned early, go for those set up is good enough already..
our car is drive on street daily, no need to spand so much money go to light weight.
of coz, safety is always stand in the first place.
If u want, u can add in firbe carbon front and rear bonnet, but it might have an impact on safety when crash.
My advise is : just go to basic light weight is good enough already. If u want to light weight on the chasis, unless ur car is track car and ready with rollcage.

 

[starscream]

Thanks you all....i understand now...and i know what to do...abort mission....hehe....you guys were right...anyhow i do have a favor...a few more questions....is it true that JE forged pistons has poor durability?? what is the life span of an original pistons compare to forged? and does ceramic coating on engine internal plays a significant role in improving the performance?

 

[FVel]

... for a small budget why not try to source for S13 original rim..? its only around 500-600 inclusive of tyre... 17" some more ..and its a 4hole 114.3 pcd

I would love to but 17" is somewhat impractical for an Iswara hehehe

 

[FVel]

fvel,
checkout WHEELWEIGHTS.NET

Thanks man