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m0rk
19-08-2002, 23:47
So - I have loads of cold air coming into my engine bay now towards my poorly positioned induction kit.

I'm thinking about sticking a Naca style duct on the bonnet to direct a little more air in there & also finishing of the bonnet jacks to lift the back of the bonnet up.

Also intending on wrapping the exhaust to keep some of that heat in the pipes & not the engine bay

Am I barking up the wrong tree?

Mark

F2 Stu
20-08-2002, 00:17
Wraping the exhuast is with the special heat proof bandage is primarily to keep the exhuast and in turn the gases hot as possible as hot gases travel more freely and thus should help performance.

A naca style duct position just b4 the filter on the bonnet will help it no end, as for venting the hot air, how about using a scooby scoop turned thru 180 degres as a large louvre, saw one on a sierra and thought I might do the same one day:o

how about taking the bonnet of completely?:D

ibizacupra
20-08-2002, 08:15
Originally posted by MarkP
So - I have loads of cold air coming into my engine bay now towards my poorly positioned induction kit.

I'm thinking about sticking a Naca style duct on the bonnet to direct a little more air in there & also finishing of the bonnet jacks to lift the back of the bonnet up.

Also intending on wrapping the exhaust to keep some of that heat in the pipes & not the engine bay

Am I barking up the wrong tree?

Mark

Naca duct would be OK and even better if you were able to construct a flexi from it to the filter, surrounding the housing completely.

I run the thermo tape on my Jetta's exhaust manifold and it reduced under bonnet temps a great deal, especially on switching off, where heatsoak set in.. The downside however on mine, was that this heat had to go somewhere and that ended up doing down the exhaust, and rubbers started melting !

regards
Bill

m0rk
20-08-2002, 08:34
I think I'd set the Naca to one side (RHS as you sit in it with a turn in it to avoid pelting it with water.

Would I have to wear a Baseball cap backwards to have a bonnet vent?

no seriously, I think I'll have a play in the next week or so as a replacement bonnet painted only cost me 100 notes if it looks sucky.

Mark

Miridor
20-08-2002, 09:14
Hay Mark better idea mate :)

On my garage floor at the mo i have a 3.9l Range Rover engine lets shoe horn that in the back with your rear seats and soom rear wheel drive running gear;)

Know that would make one driverble Seat,you could even run the car on those space savers that you used at that track day;) :laff:

Back normality now it would be intresting to see what differance a Naca style duct would make:)
Proberly much better than that crap hose you get;)

m0rk
20-08-2002, 09:52
That forms part of phase II

well, sort of

Mark

Thew
20-08-2002, 10:25
Originally posted by MarkP
So - I have loads of cold air coming into my engine bay now towards my poorly positioned induction kit.

I'm thinking about sticking a Naca style duct on the bonnet to direct a little more air in there & also finishing of the bonnet jacks to lift the back of the bonnet up.

Also intending on wrapping the exhaust to keep some of that heat in the pipes & not the engine bay

Am I barking up the wrong tree?

Mark

Where did you get that pipe from m8, I would like to run a cold air feed to my kit......was it easy to fit etc.......does it make a noise when driving at speed?

m0rk
20-08-2002, 10:31
The Elephant trunk came with the JR kit - the smaller one is from PiperCross

doddle to fit (using zip tie magic) the elephant runs from the front of the grill on the left & the black pipe runs from right down at the bottom - I'll get some pics later on

The pipe is fixed & doesn't move - or resonate, but it does feel quicker now I've moved it back from the filter a little & added the second pipe.

Mark

Thew
20-08-2002, 13:32
Can you buy these elephant trunk things on their own? I have a green induction kit but no cold air feed........ :0(

m0rk
20-08-2002, 13:36
Or something very similar - I'll dig out the red Demon Tweeks when I get home. first one I made up used tumble drier hosing - but it ran too close to the exhaust manifold once & cooked it.

Will have a look tonight
Mark

F2 Stu
20-08-2002, 17:22
Originally posted by MarkP
Would I have to wear a Baseball cap backwards to have a bonnet vent?

Nope, but act like a Max Muppet would suffice:D

ibizacupra
20-08-2002, 17:23
Originally posted by Thew
Can you buy these elephant trunk things on their own? I have a green induction kit but no cold air feed........ :0(

A Green cold air feed pipe is £35 for your info.
regards
Bill

Thew
20-08-2002, 18:15
Originally posted by ibizacupra


A Green cold air feed pipe is £35 for your info.
regards
Bill

Cheers where from?

WeeJase
20-08-2002, 18:23
thought you were getting a 2ltr 8v???
c0ck:cheers:

m0rk
20-08-2002, 18:28
I am jase

the TT lives on as it's not worth jack

M

ibizacupra
20-08-2002, 21:19
Originally posted by Thew


Cheers where from?

Badger5 Ltd (me :))
email me at bill@badger5.co.uk for more info etc...
regards
Bill

Thew
21-08-2002, 10:40
Originally posted by ibizacupra


Badger5 Ltd (me :))
email me at bill@badger5.co.uk for more info etc...
regards
Bill

Cool will save this message and give you a shout when I next have a few quid..........Cheers m8. ;)

prof
21-08-2002, 10:44
scoops are no good unless they are in a high pressure area, best places to get air are up near the base of the windscreen, where the heater gets its supply, or the front grille, you need to make sure that it wont scoop up loads of water if you are going past an artic in the rain. There are some very good articles on this oz site, using bits from B&Q etc, in fact it is an excellent site all round, but don't blame me if you get sacked while spending hours reading it all at work

cold air ducts (http://www.autospeed.com/A_1023/page1.html)

http://a11.g.akamai.net/7/11/5509/994309410/autospeed.com/site/autospeed/images/1023_00.jpg

have a search thru, there are loads of articles on the subject, with proper testing.

m0rk
26-08-2002, 00:12
Have made & fitted some bonnet jacks today, they look well ugly, but will go for a long drive tomorrow & see if they work when it's real hot.

Lifts the back up by about an inch (and most of the length of the bonnet) - bonnet shuts & locks too.

might be a summer thing I think

Mark
PS - Greenpipes sold in Halfords.

m0rk
05-09-2002, 07:25
Have fitted my bonnet jacks which has raised the bonnet about an inch or so at the back - highly unattractive, but they do work.

Off to Curborough today, so hopefully I'll get the car nice & warm there.

I went for a bit of a drive last night & drove for about 30mins 'hard' came back & the only thing that was hot was the exhaust manifold.

LDoR
05-09-2002, 12:01
A really interesting article there prof,

Cheers:cheers:

prof
05-09-2002, 12:20
that whole website has loads of good stuff on -the aerodynamic testing comparison with a beetle and a 911 is pretty interesting

typeR
06-09-2002, 00:19
How did it go with the bonnet jacks?

How did you make them and were they worth it? How bad did it make the car look?

m0rk
06-09-2002, 07:35
Originally posted by typeR
How did it go with the bonnet jacks?

How did you make them and were they worth it? How bad did it make the car look?

It kept the engine bay well cold - even when ragging.

They're not going to be a permanent fixture though. I'll take a pic when I get back from work.

Mark

m0rk
06-09-2002, 18:24
Pics of the ugly duckling

m0rk
06-09-2002, 18:24
..

m0rk
06-09-2002, 18:24
...

m0rk
06-09-2002, 18:25
Last one!

typeR
06-09-2002, 19:49
I wasn't planning on jacking it that much but without getting my hands dirty its hard to tell how high it needs to be to be effective. Doesn't look too bad but 5-10mm would be more discreet. Its still better than a vent as it doesn't look too lax flower and its not permanent.

m0rk
06-09-2002, 20:21
This was Mk1 made with 2 L shaped 21mm square aluminium in a Z shape (close up to follow)

bit too high as you are ramming air in at a fast speed!