tonytaylor

Since my 964 is used mainly as a track car I decided to make it more track friendly.

As a result the cars weight is now down to 1312kg/2886lbs - but that is with me and 11 gallons of petrol and a full Safety Devices roll cage

I weigh 69kg/152 lbs and I estimate 11 gallons of petrol to be 36kg/79lbs (unless anyone knows the true weight of 11 gallons of petrol).

This would give an "empty" weight of 1207kg/2655lbs which isn't far off my goal of 1200kg/2640lbs.

joey bagadonuts

Wow!!!

I won't ask for the laundry list of deletions (I can pretty much guess) but did you introduce additional carbon fibre aside from the boot lid? What sort of improvements have you noticed at the track? How does the acceleration compare to, say, a 964 RS, 993 RS or 996? Any other nice surprises you'd care to share?
Congrats!

Cupcar#12

I have a set of Carbon Bumpers if you need them from GT-racing. Not sure if you did those already or not.
also have a Carbon front hood and 3.8 tail if anyone needs them.

They will be on Ebay soon

tonytaylor

Joey,

The front bonnet/hood is carbon as you say but additional carbon has been used by way of the doors. I will add a carbon rear spoiler but I am still canvasing opinions on whether to go for a duck-tail, 993RS, 964 3.8RS, TurboS etc.
I haven,t been on track at this weight yet ( Tues ) but prior to recent mods the car weighed 1267kg/2787lbs.
Acceleration was then very similar/slightly faster than 964RS, until the RS shifted to 4th where I would pull away.
993RS have been able to edge away from me. ( 993RS peak power/torque is similar to mine but I have sen a dyno graph of a healthy 993RS overlaid over my plot and they have significantly better torque over the mid range)
GT3's (seemingly the most crashed 911 on trackdays) and GT3RS have a noticable extra bit on the top end.
The other change has been to swop the H+R/Bilstein coilover's to a "Cargraphic" track package which I'm 90% sure are Supercups with monoballs ( they look identical to supercups and the monoballs don't fit like supercups )

Rob,

I had considered the bumpers (and beams) but the weight loss cf the alloy beam didn't seem enough for the money spent. (and I need some lighter wheels, and perhaps an engine rebuild this winter) Do you know the weight saved?
I think shipping costs for the tail would be prohibitive

Colin 90 C2

rob, what does the 3.8 tail look like? maybe some pics.

colin

joey bagadonuts

Uh ... yeah, that's one way of putting it. Another is that on the straights they can run by you as if you're standing still. I've been on track with some 996 Cupcars and man can they go!
Thanks much for the follow up, Tony. Have fun at the track!

Cupcar#12

Wing (it's GP White)




no ducting on leading edge
this also is a GT-Racing Carbon Piece

Roygarth

Tony, have you done much to the engine?

Flying Finn

Tony,

One gallon is 6.1 lbs so 11 is 67.1 lbs.

Good job with weight reducing! My car's (993) "dry" weight is now 2706 lbs / 1227 kg, that's without oil also, you can take about 24 lbs out for oil) and DIN weight (full tank & oils) is 2854 lbs / 1295 kg.
Full tank of gas (72 L) and oil (12 L) weights about 148 lbs.

I can tell you the difference between stock 3127 lbs (factory weights are always without any options, in my car's case 3060 lbs) and current 2854 lbs is VERY noticeable! Especially on turns and braking, you'll love it!

oldtimer

hi Tony , what does the SD full cage weigh ?

tonytaylor

Piers,

"Engine" is (as yet) unopened, but has a MAF and custom rechip and decat custom exhaust. Same dyno as Christers video 298bhp(flywheel) 265ftlbs torque.

Flying Finn,

Seems I have overestimated weight loss - I was working on 7.3lbs per gallon . Are UK gallons same as US ones? I'll just have to find something else ( and I know what it is ).
You right about feeling the difference of weight loss; When I changed the seats and dumped the space saver the difference was obvious.
For those who read Porsche and 911 World I have been on track just behind the silver 911T featured this month. Whislt he was slightly slower in a straight line and out of tight turns (he had no LSD) he was noticibly faster in the faster turns (often on 3 wheels ) Only 210bhp but less than 1000kg.

Oldtimer,

I don't know the weight of the cage - someone on Rennlist quoted 110lbs.

robmug

Tony - UK gallons are approx 4.54 litres; I don't know the weight of fuel, but I guess it's lighter than water. 11 gallons of water would weigh 50kg - I can't see fuel weighing much less than that.

This would tie in with flying fin, who says 72l (15gallons) weighs 148lb.

So, I reckon your 11 gallons weighs 50kg. or 110lb.

tonytaylor

Apparently petrol is 0.73 as dense as water.

oldtimer

Tony , I look forward to following you on the track , my car is now heavier because I fitted a full Heigo steel cage , not to mention a lot of replacement parts , due to emerge from Phil H's spanner shop before end of month , in time for PCGB Brands Hatch track day. Hopefully dry as will be on road legal semi slicks.

tonytaylor

How heavy is the cage?
Is it welded or bolted?
Did it fit properly?
I doubt if I need to tell you the weight penalty is worthwhile. That was quick In time for winter