What's 100kg worth hp / kw

[Vincenzo]

Point in question

I have an AU XR6 111 rated at 168kw and weighing in at 1470kg

My Ex just bought an FG XR6 rated at 190kw and weighing in at 1760kg

Firstly, considering the AU is 290 kg lighter than the FG how much is 100kg weight saving worth in terms of hp / kw

Secondly, I hope to shortly do some modifications to the AU gaining about 50kw at the flywheel (so I have been informed) - so what increase can I expect at the wheels
(cai, pacemaker 4480, ballistic 100cpsi cat, bpr perf 98 ecu upgrade and 2 1/2" sports system)

[my67xr]

on the quarter mile, losing 100kg off the cars weight is worth 1/10 of a second

[Vincenzo]

Originally Posted by my67xr

on the quarter mile, losing 100kg off the cars weight is worth 1/10 of a second

Can you equate a tenth of a second gain on the quarter mile in terms of horsepower needed?

[V8XTasy]

the AU has a power to weight of 114kw/tonne
the FG has a power to weight of 107kw/tonne
so would need 200kw to make up for the extra 290kg, all other things being equal.

[StrikeTwiceXR6]

My experience is this: I had a BF that had full exhaust, underdrive pulley, and dynotune (173rwkw) and still it felt like it was only marginally ahead of my wifes FG. The FG Barra runs 195kw on the "bottom of the creek" quality fuel and runs at over 200kw on simple 95 octane. On 98 octane, the FG will run better once again (rumoured to produce 210kw and 420nm). The FG is no slouch despite it's weight. Not trying to start a petty power war here either. Hope this helps.

[Mr Hardware]

Three things are wrong with this thread.

1. FG's aren't 190kw, they are 200kw and 195 when the knock sensors kick in.

2. How is your AUIII 1470kg? Unless you've done some serious weight saving modifications, it'd weigh at least 100kg more than that.

3. Those mods aren't going to see 50kw at the flywheel. Maybe 50hp, if you're lucky.

[TheSneakiness]

My goal with my AU ute I had at the time was stock engine power at the wheels. I ended up with 147rwkw untuned.

Mind you the time prior I had run it up on the dyno "tuned" and with mixer ring gas it ran up 112rwkw. So blocking off the chip I had at the time and removing the mixer ring netted me 35rwkw.

I think if I had've revised my air intake and got the car flashed I would've seen 157rwkw

[Mr Hardware]

Also, just remember, unless its super easy, removing sprung weight can turn into really bad value really quickly. Reducing unsprung weight is where its at.

[ratter]

Originally Posted by my67xr

on the quarter mile, losing 100kg off the cars weight is worth 1/10 of a second

generally, racers equate 100 lbs with 1 tenth down the 1/4

[Day-mow]

Originally Posted by ratter

generally, racers equate 100 lbs with 1 tenth down the 1/4

so 50 lbs with 1/10th down the 1/8th?

[Mr Hardware]

^ someone failed maths

[trbo 6]

I have a drag time spreadsheet that I use that is fairly accurate.

Using the stock flywheel kw figures above i get this:

AU XR6 = 14.963 @ 95.67mph or 154km/h
FG XR6 = 15.250 @ 93.87mph or 151km/h

If I add 100kg to the AU and FG time difference is:

AU XR6 = 0.332s
FG XR6 = 0.283s

So it's about 0.3s per 100kg

[superroo]

Double check that weight on the au and don't believe what the rego sticker says.

My rego sticker list's the ute at high 14xx kg, yet the weigh bridge I crossed, it came in at 1790ish kg.
And there's not 300kg of crap in there either.

Cheers

[Vincenzo]

[QUOTE=Vincenzo]Point in question

I have an AU XR6 111 rated at 168kw and weighing in at 1470kg

My Ex just bought an FG XR6 rated at 190kw and weighing in at 1760kg

Firstly, considering the AU is 290 kg lighter than the FG ]


All right - according to Ford's own paperwork the AU is 164kw / 1530kg

and the FG is 195kw / 1710 kg - my apologies to those I annoyed - I was quoting other sources.

Still 180 kg difference

[Vincenzo]

Originally Posted by Mr Hardware

Three things are wrong with this thread.

1. FG's aren't 190kw, they are 200kw and 195 when the knock sensors kick in.

2. How is your AUIII 1470kg? Unless you've done some serious weight saving modifications, it'd weigh at least 100kg more than that.

3. Those mods aren't going to see 50kw at the flywheel. Maybe 50hp, if you're lucky.

There is nothing wrong with this thread - I am asking questions and learning

1. Fixed in the above reply

2. As above and will visit weigh station tomorrow to verify

3. As for 50kw / 50hp I was simply repeating what I was informed by a supposedly knowledgeable person - though he was trying to sell me a supercharger at the time

[Vincenzo]

Originally Posted by ratter

generally, racers equate 100 lbs with 1 tenth down the 1/4

Thankyou - this is what I am looking for.

[Mr Hardware]

but you've also got to remember that sometimes weight can be an advantage. removing your spare tyre to save 20kg might end up losing you time because of the weight over the rear wheels changing leading to less traction.

[mik]

there are also gears to consider, even a modded au will have to work hard to get past the extra cog/s in the later models, taking my mates bf2 zf equipped for a squirt, it made my s2 au seem like a slug, current models really have a serious turn of speed even n/a.

[DJM83]

Originally Posted by Mr Hardware

Three things are wrong with this thread.

1. FG's aren't 190kw, they are 200kw and 195 when the knock sensors kick in.

2. How is your AUIII 1470kg? Unless you've done some serious weight saving modifications, it'd weigh at least 100kg more than that.

3. Those mods aren't going to see 50kw at the flywheel. Maybe 50hp, if you're lucky.

Gee shoot someone down for asking a question, theres nothing wrong with gaining some knowledge, your bound to get some wrong info before getting the right stuff.

[Mr Hardware]

OP sorry that being frank came across as being rude