how to raise a gap for the front bonet?

[itrDC2]

Originally posted by seanlee+Sep 25 2004, 03:36 -->

QUOTE (seanlee @ Sep 25 2004, 03:36 )

--QuoteBegin-ninja_iga

@Sep 25 2004, 00:48 why do anyone want's to raise the bonnet? it only lets air from outside in! not hot air out (at speed)

yes...stan said the rite..in high speed.the cold air will blow in then the hot air out.[/b][/quote] Just for the sake of knowledge and practical discussion. Do correct me if I'm wrong. If my understanding to this case is correct, I believe hot air will come out even at speed. Reasons, air pressure travels high to low, hot to cold... Same reason how our airplanes can fly becos the air travels faster TOP of the aero wings creating lower air presure, at speed, lower than the air BELOW. Thus, higher presure below the wings creating a lift when the plane goes even faster. When the car's engine bay is so hot, and even at speed, typical air flow should flow out instead of going back in becos air pressure traveling outside the engine bay should be lower. Lower air pressure should be more than welcoming to hot air to flow out of the engine bay via the lifted hood. I too find practical application to this theory on some of those CF hood with air vents not scooping air into the engine bay but facing the air flow's direction like the following picture.. http://img.photobucket.com/albums/v77/kingauxs/z_Misc/hood-cf-hyundai-tiburon-0001-turbo1.jpghttp://img.photobucket.com/albums/v77/kingauxs/z_Misc/front_hood_type_r_im.jpg The onli difference I see here is the position of the vents which is mounted in the middle and the shape. For a lifted hood, it's a DIY vent at the back of the hood without the obvious aero shapes of the vents as of the pictures above which helps creating even higher air flow speed. DIY lifted hood may not be as effective as aero shaped cf hood but I still think air will flow out instead. (probably hoping so cos if it works, I'll lift my hood.... cheaper mah.....) Again, correct me if I'm wrong. :)

 

[ninja_iga]

itr,

thanks for the (now) intelligent discussion.
:P sorry guys......

well, using the low-pressure/ high-pressure theory to guide us where the air from the engine bay will come out or not,

here's something:

why the bonnets like these:
http://img.photobucket.com/albums/v77/kingauxs/z_Misc/front_hood_type_r_im.jpg

should work pretty well, is because the hole is in the LOW-pressure,high-speed zone. (the faster the air, the lower the pressure)
and it's right after the radiator :)
i've seen some fibre 'experts' put the vents IN FRONT of the radiator.. now that effectively reduces air from cooling the radiator la..... aiyo.

okie:
why doesn't the raised/popped bonnet let hot-air out? it worked for bonnet venting, doesn't it?
when stationary, YES the radiator fan blows the hot air out.
but when moving (fast enough la) the air from outside, actually gets pushed into the hole!
:huh: ??
how did that happened?

simple: that area is a high-pressure, low-airspeed zone.
How is that possible?
the windscreen. The air needs to SLOW down and 'climb' the windscreen. So the base of the windscreen is high-pressure (relatively)

don't you believe me?
well, our air-con air-intakes are THERE you know.. not even facing the front too! yet the air going thru the pipings-to-the-blower-to-pipings-to-your-face is still quite fast! (with the blower off) woah! try it with your car!

 

[menghua84]

err... conclusion? stanley.. good or bad for raising the hood? i seen some cars done it..

 

[ninja_iga]

waste of time IF you think raising the bonnet is to release heat from the engine bay.

but if you converted... and because the block is too tall... then no choice la

otherwise, i honestly look back (coz i did it too :P ) it's kinda ugly le..

 

[itrDC2]

air -con vents? eeh? yea loo hoo? :huh: :( haih...... cheap thing no good, good thing no cheap....

Thanks for pointing out that. :D

Conclusion,
Hood with vents in front/middle works
Lifted hood, will not work at speed. :(

Theoretical conclusion onli but I'm quite convinced, cos my aircond intake vents are indeed in that area. :D

 

[WAJA2003]

Bcs some look more garang than stock mahhh....
For the look only larr

 

[menghua84]

yaya.. for the looks mar.. any1 can get me the pic of a washer? i really duno wat is it.... got some diy pics to do it is really appreciated...

 

[ksgoh]

can show some pic on ur project done??

 

[WAJA2003]

Hmm No DIGI cam worrr
Just look like the car u see at road lahh,all same same 1 larrr
i use nut,not waste.....i buy 1 longer screw n nut to do it

 

[ksgoh]

longer screw wouldn't 'hurt" the bonet?

 

[khguan]

longer screw means can use more washers mah.... then wun touch de bonnet lor..

 

[ksgoh]

if don;t ever touch the bonet, how to "jack" the bonet higher a bit? little blur here.....

 

[ninja_iga]

the longer bolts are needed because when you 'raise' the bonnet by a say, 10mm, the bolts maybe too short for the job.

so when you put in 10mm of washers, you'll very most likely need a bolt(s) that's 10mm longer.

not too long of course, else the extra length of the bolt cannot tighten all the way because you may screw it till you touch the bonnet..

 

[JasperSSP]

hope this helps. the picture below shows stock on the left and the lifted bonet on the right. assume red colour is your car body and bonet. black one is the screw and grey thing there is the hinges. using the longer screw with the blue washers will lift your bonet but your longer screw will not touch the bonet. hope this explains everything.

 

[ksgoh]

thanks for explaination.....get some pic on it already....

 

[fstr]

hahahhaha i have done mine...DIY yesterday night...successfull,,hehehe :rolleyes:

 

[skyline7]

This method can be used for iswara models huh?Nice huh?

 

[SiGNAL]

Actually it's useless to raise ur bonnet...... other than not letting the hot air out, u are endangering ur own engine.

for example, Civic EF, because of the carb intake on the firewall, raising ur bonnet means ur letting water go in which damage ur filter if ur using open pod filter.

for wiras, those using EFI, water going in the firewall side will not favour ur TPS and sometimes will damage ur injectors and fuel rails if there is heavy downpour.

That's just my experience with lifting ur bonnet. U may try it out at ur own risk. cheers

 

[ksgoh]

ops....bonet jacker should take note on this...

 

[]\[ickless]

Just wondering... The alarm 'sensor' button (dunno wat should I call it.. :P ) mounted on the firewall.. Need to to be re-adjusted? :huh: