Weighed my car today

[Steve Brookes]

I had the opportunity to weigh my 964 C2 today. While at Oulton Park I sneaked onto the weigh bridge in the scrutineering bay. This is an old fashioned balance beam where you slide along the weights until it balances. A bit like weighing a sack of potatoes! []

Anyway, even with rear seats, undertray, footwell sound proofing and air con all removed and Recaro PPs in place of standard seats, with half a tank of fuel she came out at 1315 Kg. I guess she was really fat before the diet![]

For the record John Lile's 964RS (complete with roll cage and a more fuel) came out at 1265 Kg.

 

[benny.c]

I weighed mine on the Oulton weigh bridge too. 1,250kgs with virtually no fuel, and the spare wheel and toolkit removed.

 

[Steve Brookes]

ORIGINAL: benny.c

I weighed mine on the Oulton weigh bridge too. 1,250kgs with virtually no fuel, and the spare wheel and toolkit removed.

Glad to hear that we're not the only ones to have the cheek to borrow their weigh bridge! [][]

 

[RLambert]

My race car is about 1250kg with just under half a tank of fuel and only one recaro. I haven't done any 'special' lightening other than removing all the bits I don't need. It still has a sunroof.

The car comes in about 30kg over the min weight for the class (I'm 80kg so I could probably lose 5kg but not a lot more!) and it doesn't help that I have to run over a 1/4 tank otherwise I get fuel surge so the extra fuel weight would be around 10-15kg.

Taking out the sunroof and a fibreglass bonnet will bring the weight down a bit so I might get round to doing that at some point.

Anyone going to be at Snett this Sunday or is everyone at the Silverstone Classic ?

 

[Steve Brookes]

Must be worth you trying to lose that last few kilos from the car Richard? I think Marcus' car must be very light as he's got some lead ballast bolted to the floor to bring the car back up to the regulation weight.....even with his portly figure on board! []

 

[RLambert]

I guess it is costing me a couple of tenths so as you say it is worth doing.

At the moment I'm still refining the handling so once I'm happy with that I'll get onto the weight issue. I'm trying stiffer springs this weekend.

I could do with sorting out the fuel surge problem so I don't have to carry so much fuel. It's interesting as some drivers suffer from it and others don't. Marcus can run his car till the light comes on as could Ian White but Kevin Harrison's 964 and a couple of the 993s get surge. there doesn't seem to be a pattern as to which cars do and don't.

 

[h_____]

Bare in mind, you will have to redo the suspension setup when remove more weight.....

 

[RLambert]

Well, I mentioned fuel surge in my post on the 22nd and it that's what cost me the win in race 2 at Snett!

I had a dreadful race 1. After qualifying 4th I made a good start but was passed down the straight by all and sundry (I had a power test on Friday and it was 35hp down, not sure why as nothing seems wrong with it) so for race 2 I put in the rest of the fuel I'd taken with me.

Looking at the gauge I thought it would be touch and go but I couldn't be ar5ed to go and get some more and I figured that with the car being off the pace I didn't think it would matter if it surged a bit at the end.

BIG mistake, for some reason the motor was going better so I ended up leading for the entire race only for the dreaded fuel surge to start with 3 laps to go. Pete Morris was on my tail in one of those easy to drive 968s and on the last lap he got through on the exit of the bomb hole to take the win. I was gutted. []

After the race the gauge was showing 1/4 of a tank. I've checked the guage and it's working correctly so there was a good 20 litres in it.

Does any one else with a 964 get fuel surge on track days and if so, have you done anything about curing it or do you just put in more fuel ?

On a positive note, the handling is now sorted as it cornered on rails, until the rear tyres gave up !

Cheers

 

[Steve Brookes]

Saw the report on the motor sport website about how well you'd done at Snetterton despite the fuel surge problems at the end. Personally, I've not had any problems running low fuel - the car just gets faster [].

Can you describe to us the symptoms of 'fuel surge' because at the moment I'm not sure what your experiencing?

 

[RLambert]

At Snett, it occurs through the Bomb Hole and then at Coram. The fuel pump pick up must be on the right hand end of the tank (when viewed from the drivers seat) so when the fuel gets low it sloshes over to the left and the pump is picking up air and losing fuel pressure resulting in an engine hic up just like running out of fuel.

On this car (and my 76 Carrera) if the fuel level goes just below a 1/4 tank then it happens.

 

[Steve Brookes]

Richard, your symptoms sound very similar to the hesitation that can be experienced on the 89 and 90 cars. Sudden loss of power, often when going down hill or cruising at low revs. Indeed I had this in the first year of ownership. The times it happened, I may well have had a low tank but didn't tie the symptoms in with that (I never ran a low tank on track in the early years).

It was a problem that Porsche recongnised - they found that the plug on the air flow meter was picking up erroneous signals from close by breather pipes. So they introduced a technical service bulletin to solve the problem which involves a DIY mod to the AFM plug. You'll find the TSB here:

http://www.alldata.com/TSB/50/90504812.html

If you don't know if yours has been done (mine hadn't) it might be worth checking?

 

[RLambert]

Hi Steve,

Thanks for that but I can't get the link to work... can you try it ?

I'm pretty sure it purely a low fuel issue (as it affected my 76 car too) but as you say it is worth checking.

Cheers

 

[Steve Brookes]

Looks like that link doesn't work any more but you can get here too:

http://www.ciborg.net/share/tsb%20wire%20harness.pdf

Let us know what you find.

 

[RLambert]

Thanks Steve, I'll have a look at the weekend.

 

[jason]

Steve you really are an encyclopedia of knowledge on 964's now!!!

Thumbs up []

 

[Steve Brookes]

I still consider myself an amateur compared to Dave W []

 

[38F3E1]

ORIGINAL: Steve Brookes

I had the opportunity to weigh my 964 C2 today. While at Oulton Park I sneaked onto the weigh bridge in the scrutineering bay. This is an old fashioned balance beam where you slide along the weights until it balances. A bit like weighing a sack of potatoes! []

Anyway, even with rear seats, undertray, footwell sound proofing and air con all removed and Recaro PPs in place of standard seats, with half a tank of fuel she came out at 1315 Kg. I guess she was really fat before the diet![]

God they are fat those 964s. Getting an early to 1000 Kg is easy. Glad I sold mine .... actually no i'm not I miss it a lot.

Ian.

 

[Steve Brookes]

ORIGINAL: Ian McLeod

ORIGINAL: Steve Brookes

I had the opportunity to weigh my 964 C2 today. While at Oulton Park I sneaked onto the weigh bridge in the scrutineering bay. This is an old fashioned balance beam where you slide along the weights until it balances. A bit like weighing a sack of potatoes! []

Anyway, even with rear seats, undertray, footwell sound proofing and air con all removed and Recaro PPs in place of standard seats, with half a tank of fuel she came out at 1315 Kg. I guess she was really fat before the diet![]

God they are fat those 964s. Getting an early to 1000 Kg is easy. Glad I sold mine .... actually no i'm not I miss it a lot.

Ian.

Can't argue with your synopsis Ian []. As a comparison we weighed John's '69 911 a couple of weeks earlier on the same scales - even with all the comfortable stuff still present it only weighed 1095 Kg....and I had the pleasure of driving it for a few laps too []