I'm getting a flat bottom!
Discussion
Just wanted to keep those who are interested updated.
After hours of debate, how best to spend the money on getting the Cerb quicker, APM Andy and I have decided that rather than more power (bang on 400 bhp at the moment with a very torquey engine) we are going to finish the job on the aerodynamics as we are Racing Group A in TVR and wanting to be front runners in C in the GT Cup so we are not overstepping any regs or ethos. The Cerb is getting a flat bottom and diffuser, we'll need to run the exhausts straight out the back to help straighten the air.
We also have sourced a big Carbon Fibre wing to assist in balancing out the new lowered splitter.
So to total the upgardes for this season:
18 inch 265 and 250 slicks. Body work reshaped underneath to accomodate. A 265 slick is equal to a 290/300 road tyre in terms of footprint.
Ohlin remotes and upgraded and shorter springs.
Lowered splitter and
new aero on the front.
Tuscan box and racing clutch
Recycling oil in diff.
Big wing
Flat bottom
Diffuser
Straight exhausts.
Frankly that's it as far as we can go bodywork and cornering wise!
Have we missed anything?
Jonny
After hours of debate, how best to spend the money on getting the Cerb quicker, APM Andy and I have decided that rather than more power (bang on 400 bhp at the moment with a very torquey engine) we are going to finish the job on the aerodynamics as we are Racing Group A in TVR and wanting to be front runners in C in the GT Cup so we are not overstepping any regs or ethos. The Cerb is getting a flat bottom and diffuser, we'll need to run the exhausts straight out the back to help straighten the air.
We also have sourced a big Carbon Fibre wing to assist in balancing out the new lowered splitter.
So to total the upgardes for this season:
18 inch 265 and 250 slicks. Body work reshaped underneath to accomodate. A 265 slick is equal to a 290/300 road tyre in terms of footprint.
Ohlin remotes and upgraded and shorter springs.
Lowered splitter and
new aero on the front.
Tuscan box and racing clutch
Recycling oil in diff.
Big wing
Flat bottom
Diffuser
Straight exhausts.
Frankly that's it as far as we can go bodywork and cornering wise!
Have we missed anything?
Jonny
Ahh! Ok!
I need to bring you up to speed on the total:
Six pot brakes and big vented discs with directional air rams that blow down the centre of the discs. Back brakes are fine.
Strengthend chassis with anti torsion cross bar and Steve Heath drop downs.
Cambered and lowered suspension, now Ohlins although the Gaz were very good, with massive springs that basically give no movement.
Engine is a 2002 standard 4.5 with 4.2 breathing and intakes and an APM chip and remap for torque.
Bonnet is lightweight and glass is polycarbonate.
Inside is bare and obviuosly FIA safety spec with cage, seat cut offs etc..(Tonnes of detail but boring).
Windows all poly, rear glass.
Tank is lowered and race spec for 35 minutes at 1.25 litres a minute.
Electics boxed and diverted.
There's lots more but that should suffice!
Jonny
I need to bring you up to speed on the total:
Six pot brakes and big vented discs with directional air rams that blow down the centre of the discs. Back brakes are fine.
Strengthend chassis with anti torsion cross bar and Steve Heath drop downs.
Cambered and lowered suspension, now Ohlins although the Gaz were very good, with massive springs that basically give no movement.
Engine is a 2002 standard 4.5 with 4.2 breathing and intakes and an APM chip and remap for torque.
Bonnet is lightweight and glass is polycarbonate.
Inside is bare and obviuosly FIA safety spec with cage, seat cut offs etc..(Tonnes of detail but boring).
Windows all poly, rear glass.
Tank is lowered and race spec for 35 minutes at 1.25 litres a minute.
Electics boxed and diverted.
There's lots more but that should suffice!
Jonny
I still reckon the front wings will be heavy as hell though... and if you're flat flooring you may as well try and trap a little more air underneath to maximise its effects, though if the front splitter is lowered further there wont be much getting in there either.
Also for aero, I'd consider plates infront of the rear wheels too - see most BMW's underneath for what im on about - makes a tiny difference, but a tiny difference is all good... Our aero studies showed these to be suprisingly effective considering thier size/cost...
Other stuff, hmm... err larger steering boss or longer column, move the seat and driver further back etc etc.
I can go on if you like...
Also for aero, I'd consider plates infront of the rear wheels too - see most BMW's underneath for what im on about - makes a tiny difference, but a tiny difference is all good... Our aero studies showed these to be suprisingly effective considering thier size/cost...
Other stuff, hmm... err larger steering boss or longer column, move the seat and driver further back etc etc.
I can go on if you like... Set the single wiper blade, not two, to park vertically up the windscreen, no idea what it does but I seem to recall it being popular with the touring cars 
Here's another one, does the front opening aperture need to be so large as it just seems like a great big air brake on the front of the car to me
. Obviously only if the car can take a reduced air flow through the radiator but I would have thought a smaller opening would mean the air through it would do the same work faster with a higher speed through it, whilst providing a smaller air brake perhaps .
Maybe try packing it out a bit, with polystyrene first on a test session whilst monitoring temperatures times speeds, can't hurt and would cost the sum total of a few blocks of polystyrene and a modelling knife to prove right or wrong
Here's another one, does the front opening aperture need to be so large as it just seems like a great big air brake on the front of the car to me
. Obviously only if the car can take a reduced air flow through the radiator but I would have thought a smaller opening would mean the air through it would do the same work faster with a higher speed through it, whilst providing a smaller air brake perhaps . Maybe try packing it out a bit, with polystyrene first on a test session whilst monitoring temperatures times speeds, can't hurt and would cost the sum total of a few blocks of polystyrene and a modelling knife to prove right or wrong
Edited by HarryW on Friday 25th January 00:56
JonnyW said:
This is good stuff guys, I like the little deflectors. Side skirts, I need to check the general regs on height clearance which I think is 2 inches. Front section we looked at but £5k for basically a 40kg saving tops.
Keep going!!
I'll start charging for this soon... move (massively smaller) battery etc to the back, have a good look at Sag rear suspension mountings/ check your rollcentres and re-mount wishbones in a more optimal way if possible - change top damper mounts to allow for a more verticle layout... plastic covers for lights to smooth off the front a little (probably not worth bothering with now that you only have two tiny slots. Thin out the roof a little - lightweight bootlid too?? maybe put a crossbrace on the top of the damper mounts and triangulate to the front of the chassis... Keep going!!
- shrug* loads of stuff potentially. I'd like to thank TrackCarSolutions for some of the input on the above, I could keep going, but I'll save that stuff for my Cerb racer.
JonnyW said:
This is good stuff guys, I like the little deflectors. Side skirts, I need to check the general regs on height clearance which I think is 2 inches. Front section we looked at but £5k for basically a 40kg saving tops.
Keep going!!
If you're going down to 2" then you will need rock hard suspension (which will cost grip) or skirts.Keep going!!
HarryW said:
Here's another one, does the front opening aperture need to be so large as it just seems like a great big air brake on the front of the car to me . Obviously only if the car can take a reduced air flow through the radiator but I would have thought a smaller opening would mean the air through it would do the same work faster with a higher speed through it, whilst providing a smaller air brake perhaps .
Maybe try packing it out a bit, with polystyrene first on a test session whilst monitoring temperatures times speeds, can't hurt and would cost the sum total of a few blocks of polystyrene and a modelling knife to prove right or wrong
Probably a good call - Gaffa tape is your best friend for such experimentation, though probably not your paintworks best friend... . Obviously only if the car can take a reduced air flow through the radiator but I would have thought a smaller opening would mean the air through it would do the same work faster with a higher speed through it, whilst providing a smaller air brake perhaps . Maybe try packing it out a bit, with polystyrene first on a test session whilst monitoring temperatures times speeds, can't hurt and would cost the sum total of a few blocks of polystyrene and a modelling knife to prove right or wrong
The suspension geometry has already been changed and the triangulation on the suspension and stiffening is already in. Lowering has come with additional stiffness and therefore tyre wear and is the main reason for moving to Ohlins which are a little more forgiving on the set up even when running shorter and stiffer springs.
The air in at the front is part of what is being sucked out of the back by the splitter as I need some flow to create a negative pressure aka Bernoulli effect.
Trackcars suggestions are pretty good as they are predominantly a result of us debating and crawling over the Cerb at Snetterton over a BBQ and copius Stella!
The air in at the front is part of what is being sucked out of the back by the splitter as I need some flow to create a negative pressure aka Bernoulli effect.
Trackcars suggestions are pretty good as they are predominantly a result of us debating and crawling over the Cerb at Snetterton over a BBQ and copius Stella!
Have you thought of contacting Martin Short at Rollcentre to get some ideas of what worked well on his British GT Cerbera?
Clicky for picky
Clicky for picky
Edited by jeremyc on Friday 25th January 08:43
JonnyW said:
Trackcars suggestions are pretty good as they are predominantly a result of us debating and crawling over the Cerb at Snetterton over a BBQ and copius Stella!
Just to clarify; some of its Trackcars, alot of the stuff is my two year Cerb racer daydream... I believe Trackcar will keep his cards close to his chest so his T350 can compete effectively. Long live TVR's in motorsport. 
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