Weight Balance

Seduce XR6 · 19-09-2011, 09:34 AM

Might sound like a silly question though I will ask it anyway as am sure somebody on here would know the answer, lets see who really is the Ford Guru on AFF

What is the weight balance on a FG I6 Falcon as in front to rear etc?

I would guess they are front heavy at around 65% front 35% rear, any takers?

SteveJH · 19-09-2011, 03:02 PM

Quote:

Originally Posted by Seduce XR6

Might sound like a silly question though I will ask it anyway as am sure somebody on here would know the answer, lets see who really is the Ford Guru on AFF

What is the weight balance on a FG I6 Falcon as in front to rear etc?

I would guess they are front heavy at around 65% front 35% rear, any takers?

Not me, but i doubt the weight distribute is that far to the front. How much do the spare and IRS weigh?

MAD · 19-09-2011, 03:35 PM

Which gearbox?

FalconXV · 19-09-2011, 03:45 PM

55.5% front : 44.5% rear.

Seduce XR6 · 19-09-2011, 03:53 PM

ZF Box, thanks guys I did not think it would be that far to the front (65/35) specially on the NA 6 however I thought me saying 65/35 might just make some more keen to tell me I was wrong & thus give me an answer lol

So assuming he is right FalconXV gets the prize which is simply a ty from me & Recognition as being a Ford guru

Seduce XR6 · 19-09-2011, 03:56 PM

So next question would be how much weight would you need to transfer to the rear to make it 50/50 & could that even be done?

And will the upcoming 2 Litre have a better balance?

Hally · 19-09-2011, 04:14 PM

two fat blokes in the back seat?

XR6_661 · 19-09-2011, 04:17 PM

Quote:

Originally Posted by Hally

two fat blokes in the back seat?

That'll do.

sudszy · 20-09-2011, 07:51 AM

Quote:

Originally Posted by Hally

two fat blokes in the back seat?

If we take the 55.5/45.5 numbers at face value, thats about 935/765 on a 1700kg Falcon.
To be 50/50, 85kg would have to go from directly above the front wheels to directly above the back wheels.......or put about 2 x 85kg in the back seat, yep two fat blokes.

Yep, you can move lighter things further past the axles to achieve the same effect, but that can affect the dynamics in other ways.

Really though the cars are setup pretty well, if they started at 50/50 empty they'd end up horrible once you've put the driver in and with any sort of a load in the boot or rear seat.

aussie muscle · 20-09-2011, 08:55 AM

Quote:

Originally Posted by Hally

two fat blokes in the back seat?

reminds me when i had to fat blokes get in my valiant. they both sat on the passenger side, and the weight changed the handling of the 25 yo suspension that the car wouldn't drive straight!

dimka100 · 20-09-2011, 10:13 AM

While generally speaking 50/50 Front to Rear weight distribution is a good thing, it’s not always the best outcome the engineers are trying to achieve. When it comes to car handling the car’s static (stationary) weight distribution is not as important as the actual weight distribution when the car is moving. For example:

When the car is braking the weight distribution will always move Forward (i.e. front biased)
When the car is accelerating hard the weight distribution will always move backwards (i.e. rear biased)
When the car is turning the weight distribution will move to the front and the cornering side, and then progressively balance back to the centre while moving rearwards as the car begins to accelerate out of the corner.

That shift in the vehicles mass will generate additional pressure on the tyres hence increasing grip, which will help when braking, accelerating, and cornering …

Many racing cars are actually setup to not be perfectly equal while stationary, however when driven at their expected speed they will achieve the required weight distribution for ultimate performance in the required circumstances

sudszy · 20-09-2011, 11:24 AM

Quote:

Originally Posted by dimka100

When the car is braking the weight distribution will always move Forward (i.e. front biased)

in most cases yes, but if the C of G is at axle height(which is effectively how formula one is setup) there will be no "weight" transfer effect.

SteveJH · 20-09-2011, 04:59 AM

Quote:

Originally Posted by Seduce XR6

So next question would be how much weight would you need to transfer to the rear to make it 50/50 & could that even be done?

And will the upcoming 2 Litre have a better balance?

Moving the battery to the boot would have to make it pretty close.

And most likely.

jpd80 · 20-09-2011, 05:20 AM

The I-6 versions are most likely 55% F 45% R but the iron block 5.4 Boss probably changed that to more like
60% F 40% R which is similar to a FWD Cars weight balance and probably why the V8s used to feel a touch nose heavy...

SteveJH · 20-09-2011, 06:08 AM

How much does a typical lead-aid battery weigh? If you moved it to the boot...multiply that by 2 and you get the rearward weight shift.

Would have to be about a 50kg net change?

Seduce XR6 · 20-09-2011, 07:56 PM

Quote:

Originally Posted by SteveJH

How much does a typical lead-aid battery weigh? If you moved it to the boot...multiply that by 2 and you get the rearward weight shift.

Would have to be about a 50kg net change?

Yes I was thinking exactly the same, ty for the input

MAD · 19-09-2011, 04:09 PM

50/50 isnt always the best. The way it transfers the weight, under different conditions, is more important.

Seduce XR6 · 20-09-2011, 04:57 AM

lol so where can I hire a couple of Sumo's?

XR6_661 · 20-09-2011, 10:15 AM

Quote:

Originally Posted by Seduce XR6

lol so where can I hire a couple of Sumo's?

No need for that mate, go pick up a couple of fat chicks. It's like fishing with dynamite.

GTP-814 · 20-09-2011, 11:55 AM

Quote:

Originally Posted by Seduce XR6

lol so where can I hire a couple of Sumo's?

Look on any public transport system & you will find a coulple of heavy weights

MexicanBatman · 20-09-2011, 12:22 PM

fat blokes are 85kg now?

WOW

sudszy · 20-09-2011, 12:36 PM

Quote:

Originally Posted by MexicanBatman

fat blokes are 85kg now?

WOW

LOL, thought that may get a reaction, ave male height = 178cm in Aus, at 85kgs that a bmi of 27, = fat bloke. (yes i appreciate there are muscle bound types(afl players) who arent carrying an ounce of fat, that might fit those numbers, but they are the exception)

geckoGT · 20-09-2011, 12:50 PM

The Op asked about finding out weight distribution specs, I am thinking this has gone a little bit OT.

Seduce XR6 · 20-09-2011, 08:05 PM

While I can almost understand all that tech speak it does leave me a little lost though taking 1 part of it which I feel is relevent to myself & my reasons for asking is that if you have that many kilos of extra weight on the front would that not under hard braking make the extra weight more of an inluence than it would be under normal driving conditions thus making the not so bad balance as some have said rather bad?

As in a multiplier effect of sorts?

Moving the battery into the boot in one of those battery boxes sounds good though would you then lose some effect of the alternator as the cables would be much longer than they were under the bonnet?

sudszy · 20-09-2011, 09:09 PM

Quote:

Originally Posted by Seduce XR6

my reasons for asking is that if you have that many kilos of extra weight on the front would that not under hard braking make the extra weight more of an inluence than it would be under normal driving conditions thus making the not so bad balance as some have said rather bad?

If you go adding extra mass to the front of the car, then yes, it can upset how the car was designed. But Im guessing you are talking about moving some mass that is already there to the back of the car? My advice, dont go 2nd guessing the engineers that designed your car. The front rear/brake bias is set up with what is already there and is more biased than the static weight ratio, though under extreme braking I believe the ABS takes over completely.

Quote:

Originally Posted by Seduce XR6

Moving the battery into the boot in one of those battery boxes sounds good though would you then lose some effect of the alternator as the cables would be much longer than they were under the bonnet?

A battery weighs about 16kg or so, yep moving it from one end to the other will make a difference, whether its a positive difference, dont know. Personally would prefer as much boot room as possible, cant go putting the shopping where the battery was under the bonnet. Also you'll need an expensive non acid battery or have proper venting to the outside.

Quote:

Originally Posted by Seduce XR6

would you then lose some effect of the alternator as the cables would be much longer than they were under the bonnet?

Charging the battery isnt the main issue, its having enough voltage to turn over the starter. Basically you'll need thicker cable from batt to starter, a good engine to earth connection and a good battery to ground connection in the boot. VE commodores have rear mounted battery, have a look at their setup. I believe there is a smart setup there which has the alternator voltage go higher when the battery is charging to overcome the voltage drop in the wire and reduces the output when the charge current drops.
Doing it properly raised the level of complexity significantly, do you really want to do this for next to no gain?

SteveJH · 20-09-2011, 09:17 PM

Quote:

Originally Posted by Seduce XR6

Moving the battery into the boot in one of those battery boxes sounds good though would you then lose some effect of the alternator as the cables would be much longer than they were under the bonnet?

Might depend on what the replacement cable is made of and what the standard cable is.

SteveJH · 20-09-2011, 09:25 PM

The worry is that if you change the weight balance you might have to completely redo your suspension if you want to take advantage of it.

And since most of the available aftermarket options would have been developed with a standard car, you'd possibly have to get something custom made?

Road_Warrior · 20-09-2011, 09:37 PM

If you relocated the battery to the boot, some voltage drop would be inevitable when power was demanded from the battery (like starting) however use say No. 6 B&S battery cable (i.e heavy gauge) and a good earth this can be minimised

And yes it would need to be vented to the outside, or alternatively use an AGM battery that is not filled with lead acid and you won't have to vent it

Seduce XR6 · 21-09-2011, 08:08 AM

Thanks for the replies guys & girl

It sounded like a good idea when I first thought of it however now I am not so sure, maybe I will just work over the suspension & leave the weight balance alone lol

I never knew the VE's battery was in the boot & I have looked over one on a test drive when they first came out, I will pop into my local Holden dealer & have a look not that I dont believe you is just I am amazed by this lol

Ok thanks again guys