mantamark
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Registered: 19th Jun 06
Location: Northumberland
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That would be the only point i would think.
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Butler
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Registered: 2nd Jun 05
Location: London
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Holes in the rear bumper reduce drag.
Il get some new pics up of my Rallye soonish 
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mantamark
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Registered: 19th Jun 06
Location: Northumberland
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Reduce drag?
Never thought about it like that.
Has it been tested to do so?
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dhdev
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Registered: 22nd Dec 05
Location: Midlands
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Cheers Mantamark!
The holes are there for both the above mentioned reasons (weight saving and drag) I know the weight loss is minimal but every little helps. The drag hasn't been proven as such, but I think its fairly logical that (in simple terms) it reduces the 'parachute' effect that the rear bumper will have.
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Butler
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Registered: 2nd Jun 05
Location: London
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My 106 Rallye for those who don't know it...
It still needs alot of work and progress has been slow recently but here are some recent pics since my brother most kindly washed it for me for the first time in my possession which is about 8 months lol.
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Ste
Premium Member
Registered: 5th Mar 03
Location: Taif, Saudi Arabia
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quote:
Originally posted by dhdev
Cheers Mantamark!
The holes are there for both the above mentioned reasons (weight saving and drag) I know the weight loss is minimal but every little helps. The drag hasn't been proven as such, but I think its fairly logical that (in simple terms) it reduces the 'parachute' effect that the rear bumper will have.
You have infact done the opposite, a parachute has a hole or holes in the top to let air out, it acts as a big funnel slowing the air passing through it.
leaving the bumper intact creates an airbubble that would deflect air around it as it has no way of going through. similar effect to a golf ball, the dimples create airbubbles that "lubricate" it through the air, giving straighter and further flight.
anyways, here is my 'weekend racer'
I would rather lose by a mile because i built my own car, than win by an inch because someone else built it for me.
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dhdev
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Registered: 22nd Dec 05
Location: Midlands
User status: Offline
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quote:
Originally posted by Ste W
quote:
Originally posted by dhdev
Cheers Mantamark!
The holes are there for both the above mentioned reasons (weight saving and drag) I know the weight loss is minimal but every little helps. The drag hasn't been proven as such, but I think its fairly logical that (in simple terms) it reduces the 'parachute' effect that the rear bumper will have.
You have infact done the opposite, a parachute has a hole or holes in the top to let air out, it acts as a big funnel slowing the air passing through it.
leaving the bumper intact creates an airbubble that would deflect air around it as it has no way of going through. similar effect to a golf ball, the dimples create airbubbles that "lubricate" it through the air, giving straighter and further flight.
Ok, so when you swing a tennis racket with its cover on it requires a significantly greater force than the same racket uncovered (full of holes) 
I'm not trying to come across as cocky, just trying to learn! I'm in my 1st year of mech eng deg and I'm just trying to make the most of an oppurtunity to learn something.
I've done a sketch (rough) of what I think is going on, and with the holes would it not reduce the turbulent low pressure wake at the rear?
[Edited on 21-02-2008 by dhdev]
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mantamark
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Registered: 19th Jun 06
Location: Northumberland
User status: Offline
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That make sense to me.
And i'm an eeeeejit.
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SportBoy
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Registered: 5th Oct 01
Location: Retford, Nottinghamshire
User status: Offline
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not a full on trackcar but being as me/it finally did a trackday and it really suprised me how well it did
280ish bhp let
Spax adjustable struts
whiteline rear arb
front tiebars lowered
reyland 4pot brake , 305mm discs
16" softstars with goodyear gsd3's
[Edited on 21-02-2008 by SportyBoy]
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SVM 286
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Registered: 13th Feb 05
Location: pain
User status: Offline
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Here are mine...
Neither of them are currently road or track worthy but should be in about two and a half years  
So they'll see some action then.
I'm patient if nothing else.
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RCS
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Registered: 26th Jan 05
Location: Lichfield/Dundee
User status: Offline
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SVM 286 was your car part of a max power feature a good few years ago?
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SVM 286
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Registered: 13th Feb 05
Location: pain
User status: Offline
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Yes sir.
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SVM 286
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Registered: 13th Feb 05
Location: pain
User status: Offline
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It was in about 3 or 4 magazine articles about 10 years ago. The image below was from one of them.
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RCS
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Registered: 26th Jan 05
Location: Lichfield/Dundee
User status: Offline
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I remember it in the aRSe kickers feature. Ever since I always wanted a black car with black wheels.
Whats happening with it now?
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wilson_sri
Member
Registered: 31st Aug 04
Location: Dunfermline Drives: Technics 1210s
User status: Offline
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Heres mine.
Nova saloon trip shell.
c16se nova gsi engine
1.8 sierra carb (now changing to twin 40)
Rally cam
4-1 manifold
straight through exhause
Custom stock rod springs
gaz shocks
braided brake lines
2 litre brakes
astra GTE wheels on road legal slicks
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SVM 286
Member
Registered: 13th Feb 05
Location: pain
User status: Offline
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quote:
Originally posted by RCS
I remember it in the aRSe kickers feature. Ever since I always wanted a black car with black wheels.
Whats happening with it now?
Very little
She's sulking in the garage. 
Waiting for funds actually.
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DannyB
Premium Member
Registered: 6th Feb 08
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Yeh i remember it SVM take some pics of the feature if you still have it, would be nice to remember it abit more as i saw it back then.
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N90ATH
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Registered: 10th Sep 03
Location: Boreham, Essex
User status: Offline
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mine a work in prgress and will post upm a spec when its finishe dlol
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Ian
Site Administrator
Registered: 28th Aug 99
Location: Liverpool
User status: Online
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That's certainly changed a bit!
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N90ATH
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Registered: 10th Sep 03
Location: Boreham, Essex
User status: Offline
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lol yer spent quite a bit of cash scicne most ppl saw her lol
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corsa_rob
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Registered: 22nd Jan 06
Location: Birmingham
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quote:
Originally posted by Ian
That's certainly changed a bit!
bloody hell yeah!
ive got a pic of her from ages back, what happened? in a gud way
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N90ATH
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Registered: 10th Sep 03
Location: Boreham, Essex
User status: Offline
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blew engine up before i sold it and thought fuck it fit the parts i have for her then spent too much lol
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Graham88
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Registered: 16th Apr 07
Location: South East Kent Drives: E46 M3
User status: Offline
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Jesus, that looked almost standard the last time I saw it at Bas!
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loo_goblin
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Registered: 14th Jul 04
Location: Horsham, West Sussex
User status: Offline
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My dads/mine, just needs exhaust manifold and air filter sorting, then stripped and caged
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Butler
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Registered: 2nd Jun 05
Location: London
User status: Offline
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Woah Nath, that looks flippin awesome dude
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