Jump to content
SAU Community

balance

Boris
 Share

Recommended Posts

Boris Apprentice

Boris

Posted
Posted

just curious as to whether serious weight loss tactics will affect the balance of the car?

the usual: stripped interior, carbon fibre boot/bonnet etc.

i havent been able to find the front rear weight distribution of the gtr's but wouldnt massively reducing the weight of the body while leaving the engine same unbalance the car?

im guessing more torque would be taken to the front wheels more often... tho i got no idea

Link to comment
https://www.sau.com.au/forums/topic/54781-balance/
Share on other sites
MANWHOR3 Proficient

MANWHOR3

Posted
Posted

mate, your idea of "serious weight loss" is not really serious at all.

it's been covered like 100 billion times before. gtr bonnet, not heavy. carbon bonnet might save 3-4 kilos. stripped interior - might save 25 kg. boot - might save 20 kg.

that's hardly going to unbalance anything. Think about the difference between an average aussie (100kg) driving it, and a small japanese dude (60kg) driving it, and you have the difference in weight.

Link to comment
https://www.sau.com.au/forums/topic/54781-balance/#findComment-1071622
Share on other sites
Abo Bob Grand Master

Abo Bob

Posted
Posted

Well I have driven eastern creek with full trim, subbie in the boot etc then I took the subbie, spare, jack, carpets and sundry other crap out and did some more laps. The back end was noticeably looser in braking situations both straight line and corners but it was harder to tell whether it made any difference with the power down. Perhaps that's because I don't have all that much power though.

This is with stock GTT suspension. I guess if your suspension was adjustable you could compensate.

Link to comment
https://www.sau.com.au/forums/topic/54781-balance/#findComment-1071699
Share on other sites
Boris Apprentice

Boris

Posted
  • Author
Posted

see that ETC.???

that means theres more sh!t that i couldnt be bothered writing

ripping out rear and passenger seats, lexan windscreen and windows, 1 headlight buh-bye, centre console and all audio gone, all lining and soundproofing gone, digital drag spec tacho, carbon fibre boot/bonnet. HELL, carbon fibre the whole car, dash EVERYTHING. hell screw the dash who needs it.

and get the skinniest, smallest guy u can find, and starve him for 5 weeks if that makes u happy.

and fuel for one run at a time if u want!

so yeah, when i said serious weight loss, I MEANT SERIOUS WEIGHT LOSS

so do i need to go back to the word ETC.??

and if doing these things dont matter, WHY THE FARK DO THEY DO IT???

o im just talking about the gtr's btw, thats why i made a comment about the torque transfer to the front wheels

sorry to get all shitty on ya manwhor3, but ur "tone" just pissed me off

sounded to me like:

mate, ur a dum ***, i said it 100BILLION times already blah blah blah so there!

even if it only ends up being 300kg saving, a 400kw gtr full trim at around 1600kgs 4kg/kw power/weight would become 3.25kg/kw

sorry if that wasnt ur intention, it just soudned to me like u were talking to a dum noob kid who doesnt know jack sh!t

well at least now i made myself clearer, and ill remember to do that in future too

Link to comment
https://www.sau.com.au/forums/topic/54781-balance/#findComment-1072651
Share on other sites
Sydneykid Grand Master

Sydneykid

Posted
Posted

Hi Boris, there is a great disparity in knowledge on any forum, this one is no different. You really have to be quite explicit (sorry but "etc" doesn't cut it when leaving a lot to the imagination of an unknown reader).

To the questions at hand..............

The lightest GTR I have seen was 1320 kgs, lots of stuff was removed, but the sort of stuff you take out doesn't weigh much (except glass, that's heavy). The problem is the stuff you put in tends to be heavy stuff, eg; roll cage, oil cooler, extra sump capacity, larger intercooler, bigger brakes, larger wheels, bigger tyres, LSD, bigger turbo/turbos, 4" exhaust....you get the drift.

I have taken at least 200 kgs out of ours, but it only weighs 50 kgs less than a standard one. On the bright side if I hadn't taken out the 200 kgs it would be 150 kgs heavier than standard.

The next problem is weight distribution, our is around 68% front and 32% rear. The problem being most of the weight you remove affects the rear, stuff like rear seats, spare wheel, tool kit, NVH weights, rear wiper, HICAS..... But the weight you add ends up on the front, oil cooler, remote filter, larger intercooler, turbo/turbos, larger radiator.....

I have a rule, if I have to have it, is there some way I can move it towards the rear (that means anywhere past the front wheels). And can I move to somewhere lower down, in circuit racing C of G is important too.

Hope that helps:cheers:

Link to comment
https://www.sau.com.au/forums/topic/54781-balance/#findComment-1073547
Share on other sites
Boris Apprentice

Boris

Posted
  • Author
Posted

thanks sydneykid ill take ur advice into accound for next time.

do u find the huge shift in weight to the front affects ur times or overall diveablilty of the car? (im thinking more circuit oriented then drag, where chassis balance is a lot more of an issue)

apart from trying to move things to the back, anything else u do?

my guess was that alot more torque would be transfered to the front wheels. (in the gtr). but i notice on the metre it only transfers uo tp 50kgm, which is only 500nm. hehe only...

would this be a problem for serious cars with over 1000bhp 1200 nm torque trying to get more power to the front wheels for grip?

in essence, would the car turn into an almost fwd, when the vast majority of torque is sent to the front?

Link to comment
https://www.sau.com.au/forums/topic/54781-balance/#findComment-1073672
Share on other sites
Sydneykid Grand Master

Sydneykid

Posted
Posted
thanks sydneykid ill take ur advice into accound for next time.

do u find the huge shift in weight to the front affects ur times or overall diveablilty of the car? (im thinking more circuit oriented then drag, where chassis balance is a lot more of an issue)

apart from trying to move things to the back, anything else u do?

my guess was that alot more torque would be transfered to the front wheels. (in the gtr). but i notice on the metre it only transfers uo tp 50kgm, which is only 500nm. hehe only...

would this be a problem for serious cars with over 1000bhp 1200 nm torque trying to get more power to the front wheels for grip?

in essence, would the car turn into an almost fwd, when the vast majority of torque is sent to the front?

Hi Boris, I'll try and answer briefly, I have yet to see a circuit with 1000 bhp, they mostly max around the 600 to 700 bhp. This is to keep the response up, far more important on the circuit. The best the ATTESSA will do is 50% to the front, so it can never get to what I would consider the "front wheel drive" stage. We run the circuit cars around 20 to 30% front drive. If you have too much drive to the front the tyres start to overheat, from the turning, braking and powering. The rear tyres don't do any turning and 40% less braking. So you balance the tyre load out, that's why GTR's were such circuit race killers.

Hope that answered your questions:cheers:

Link to comment
https://www.sau.com.au/forums/topic/54781-balance/#findComment-1074535
Share on other sites
Boris Apprentice

Boris

Posted
  • Author
Posted
Hi Boris, I'll try and answer briefly, I have yet to see a circuit with 1000 bhp, they mostly max around the 600 to 700 bhp.  This is to keep the response up, far more important on the circuit.  The best the ATTESSA will do is 50% to the front, so it can never get to what I would consider the "front wheel drive" stage.  We run the circuit cars around 20 to 30% front drive.  If you have too much drive to the front the tyres start to overheat, from the turning, braking and powering.  The rear tyres don't do any turning and 40% less braking.  So you balance the tyre load out, that's why GTR's were such circuit race killers.

Hope that answered your questions:cheers:

Great answer. although its raised another question for me.

i mentioned that attessa only maxes at 50% to the front, but i noticed on the gtr guages that the reading maxes out at 50 KGM (which is 500nm).

i had always thought the reading is just a percentage, but since seeing that i wasnt so sure (although it makes sense because there would be a max load the front wheels/drivetrain could take, and if it was 50%, and u had modified the car to produce over 1200 newtons of torque, more than 600 newtons could go to the front) which might cause problems

i only used 1000hp as an example. 1000hp is common in japanese drag circles from what ive seen but yeah u are completely right 600-800 hp would be much more suited to track

i did see however on top gear, that clarkson guy runnning the 1000hp jun r33 around a circuit. while he said that it was bloody scary when it came on boost (and at a corner!) it went around fine (although i dont know if they ran full boost)

and it was for sale at 150k pounds...

1000hp.... :flower: :jump: :burnout:

Link to comment
https://www.sau.com.au/forums/topic/54781-balance/#findComment-1075552
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • Duncan
      Duncan's V37.......race car?

      By Duncan · Posted

      From there, it is really just test and assemble. Plug the adapter cables from the unit into the back of the screen, then the other side to the car harness. Don't forget all the other plugs too! Run the cables behind the unit and screw it back into place (4 screws) and you should now have 3 cables to run from the top screen to the android unit. I ran them along the DS of the other AV units in the gap between their backets and the console, and used some corrugated tubing on the sharp edges of the bracket so the wires were safe. Plug the centre console and lower screen in temporarily and turn the car to ACC, the AV should fire up as normal. Hold the back button for 3 sec and Android should appear on the top screen. You need to set the input to Aux for audio (more on that later). I put the unit under the AC duct in the centre console, with the wifi antenna on top of the AC duct near the shifter, the bluetooth antenna on the AC duct under the centre console The GPS unit on top of the DS to AC duct; they all seem to work OK there are are out of the way. Neat cable routing is a pain. For the drive recorder I mounted it near the rear view mirror and run the cable in the headlining, across the a pillar and then down the inside of the a pillar seal to the DS lower dash. From there it goes across and to one USB input for the unit. The second USB input is attached to the ECUtec OBD dongle and the 3rd goes to the USB bulkhead connected I added in the centre console. This is how the centre console looks "tidied" up Note I didn't install the provided speaker, didn't use the 2.5mm IPod in line or the piggyback loom for the Ipod or change any DIP switches; they seem to only be required if you need to use the Ipod input rather than the AUX input. That's it, install done, I'll follow up with a separate post on how the unit works, but in summary it retains all factory functions and inputs (so I still use my phone to the car for calls), reverse still works like factory etc.
    • Duncan
      Duncan's V37.......race car?

      By Duncan · Posted

      Place the new daughterboard in the case and mount it using the 3 small black rivets provided, and reconnect the 3 factory ribbon cables to the new board Then, use the 3 piggyback cables from the daughterboard into the factory board on top (there are stand offs in the case to keep them apart. and remember to reconnect the antenna and rear cover fan wires. 1 screw to hold the motherboard in place. Before closing the case, make a hole in the sticker covering a hole in the case and run the cable for the android unit into the plug there. The video forgot this step, so did I, so will you probably. Then redo the 4 screws on back, 2 each top and bottom, 3 each side and put the 2 brackets back on.....all ready to go and not that tricky really.      
    • Duncan
      Duncan's V37.......race car?

      By Duncan · Posted

      Onto the android unit. You need to remove the top screen because there is a daughterboard to put inside the case. Each side vent pops out from clips; start at the bottom and carefully remove upwards (use a trim remover tool to avoid breaking anything). Then the lower screen and controls come out, 4 screws, a couple of clips (including 3 flimsy ones at the top) and 3 plugs on the rear. Then the upper screen, 4 screws and a bunch of plugs and she is out. From there, remove the mounting brackets (2 screws each), 4 screws on the rear, 2 screws top and bottom and 3 screws holding in the small plates on each side. When you remove the back cover (tight fit), watch out for the power cable for the fan, I removed it so I could put the back aside. The mainboard is held in by 1 screw in the middle, 1 aerial at the top and 3 ribbon cables. If you've ever done any laptop stuff the ribbon cables are OK to work with, just pop up the retainer and they slide out. If you are not familiar just grab a 12 year old from an iphone factory, they will know how it works The case should now look like this:
    • Duncan
      Duncan's V37.......race car?

      By Duncan · Posted

      Switching the console was tricky. First there were 6 screws to remove, and also the little adapter loom and its screws had to come out. Also don't forget to remove the 2 screws holding the central locking receiver. Then there are 4 clips on either side....these were very tight in this case and needed careful persuading with a long flat screw driver....some force required but not enough to break them...this was probably the fiddliest part of the whole job. In my case I needed both the wiring loom and the central locking receiver module to swap across to the new one. That was it for the console, so "assembly is the reverse of disassembly"
    • Duncan
      Duncan's V37.......race car?

      By Duncan · Posted

      But first....while I was there, I also swapped across the centre console box for the other style where the AV inputs don't intrude into the (very limited !) space.  Part# was 96926-4GA0A, 284H3-4GA0B, 284H3-4GA0A. (I've already swapped the top 12v socket for a USB bulkhead in this pic, it fit the hole without modification:) Comparison of the 2: Basically to do the console you need to remove the DS and PS side console trim (they slide up and back, held in by clips only) Then remove the back half of the console top trim with the cupholders, pops up, all clips again but be careful at the front as it is pretty flimsy. Then slide the shifter boot down, remove the spring clip, loose it forever somewhere in the car the pull the shift knob off. Remove the tiny plastic piece on DS near "P" and use something thin and long (most screwdrivers won't fit) to push down the interlock and put the shifter down in D for space. There is one screw at the front, then the shifter surround and ashtray lift up. There are 3 or 4 plugs underneath and it is off. Next is the rear cover of the centre console; you need to open the console lid, pop off the trim covering the lid hinge and undo the 2rd screw from the driver's side (the rest all need to come out later so you can do them all now and remove the lid) Then the rear cover unclips (6 clips), start at the top with a trim tool pulling backwards. Once it is off there are 2 screws facing rearwards to remove (need a short phillips for these) and you are done with the rear of the console. There are 4 plugs at the A/V box to unclip Then there are 2 screws at the front of the console, and 2 clips (pull up and back) and the console will come out.
×
×
  • Create New...