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Lifting rear of bonnet for cooling?

Posted: Thu Oct 31, 2013 9:16 pm
by troopiec
Hi guys, just want some knowledgeble opinions on lifting the rear of your bonnet with washers. First of all i do not like how it looks atall, i like i clean well aligned body, but with my topmount manifold and turbo im just thinking of any ideas to get some of that latent heat out of the engine bay without having to cut my stock bonnet to place a vent, does lifting the rear of the bonnet help cooling or can it actually push the hot air back?

I read up on a few forums. honda tech, driftworx, etc and all of the guys have different views, some say when the bonnet is lifted it can actually prevent hot air from escaping normally as it forms a high pressure or something like that, and then other guys say yes it does allow hot air to escape.

Any thoughts or experiences?

thanks.

Re: Lifting rear of bonnet for cooling?

Posted: Fri Nov 01, 2013 6:51 am
by Gary57
Rather vent the bonnet if you have heat issues.

Ceramic coat manifold, about R1250, works like a dream. If you have overheating issues, fit bigger radiator and bigger fans... Lifting the back of bonnet is Gheto and looks kak.

Re: Lifting rear of bonnet for cooling?

Posted: Fri Nov 01, 2013 7:04 am
by troopiec
Really couldn't afford to ceramic coat my manifold, but I sprayed it with high heat spray and wrapped it nice and thick with some good quality wrap, it keeps the heat down nicely, I'm not having any overheating issues atall, I have a full alluminium uprated radiator already and run good quality 75percent coolant, operating temps sit as per standard no problem, but I just want to release some hot air from around the turbo just to help keep the under bonnet temps low you know. I'll do a vent if I have a spare bonnet, but I don't want to cut on my one and only bonnet

Re: Lifting rear of bonnet for cooling?

Posted: Fri Nov 01, 2013 9:16 am
by SonOfAnarchy ZA
I personally like that ckean look but if you not having overheating issues then no need to stress. From what I heard raising the bonnet does work

Sent from my GT-I9500 using Tapatalk

Re: Lifting rear of bonnet for cooling?

Posted: Fri Nov 01, 2013 11:30 am
by Drillergy
Front smash= decap.
Nuff said now move along

Re: Lifting rear of bonnet for cooling?

Posted: Fri Nov 01, 2013 12:26 pm
by DriftZ
doesnt sound like you actually have cooling problems to start with,, if it aint broke .. dontushhitt.. also remember turbos actually like heat so unless your'e trying to cure a heat soak issue / across your bay to other areas like Intake.. i wouldnt bother.

That said i have done this mod before ( mod lol... its just a couple washers really ) but i did it as a shortcut to a cooling issue i was having on track ... and well it worked!! car ran 15deg + cooler i dont care what anyone says and ive never been decapitated, infact by my calculations you stand less chance of a decap with this mod ( but i did fail maths so who knows :P ). But as soon as i actually sorted my cooling issues with real parts i dropped the bonnet down to standard.

...rather spend your money / time on your girlfriend :)

Re: Lifting rear of bonnet for cooling?

Posted: Sun Nov 03, 2013 11:42 am
by mario_200sx
Lifting bonnet at the rear is a bad idea, it actually makes cooling worse on the S13. Air flow is disrupted dramatically.

Re: Lifting rear of bonnet for cooling?

Posted: Mon Nov 04, 2013 7:35 am
by Draco
Freddy(Chemcool) actually tested this, he had a temp guage to take the temp inside the engine bay, after lifting the rear he recorded 10' C plus drop depending on wheather and driving.

When I did thes, I stood next to my windshield at front door and when the fans came on I fealt the heat blown out onto the windshield.

Re: Lifting rear of bonnet for cooling?

Posted: Wed Nov 20, 2013 3:35 pm
by BigKriss
Lifted mine as well, 10deg cooler at Swartkops on water and 15 on oil temp. Ducted the front and could drop the bonnet down again. The best for me was ducting and boxing in all the coolers..

Re: Lifting rear of bonnet for cooling?

Posted: Wed Nov 20, 2013 4:26 pm
by mario_200sx
BigKriss wrote:Lifted mine as well, 10deg cooler at Swartkops on water and 15 on oil temp. Ducted the front and could drop the bonnet down again. The best for me was ducting and boxing in all the coolers..
Ducting is the best solution.... works a treat.

Re: Lifting rear of bonnet for cooling?

Posted: Sat Jan 11, 2014 11:13 am
by aep886
what we use to do overseas, we took the bonnet off for drag and track days! it 4 nuts and 2 lines for window washer! with proven result,

Re: Lifting rear of bonnet for cooling?

Posted: Fri Jan 17, 2014 7:48 pm
by mario_200sx
Many tracks wont allow that.

Re: Lifting rear of bonnet for cooling?

Posted: Mon Jan 20, 2014 3:46 pm
by Obsession
Ok, so please explaine how i lift my bonnet. Body side or Bonnet side? Have to set the latch again?

Re: Lifting rear of bonnet for cooling?

Posted: Tue Jan 21, 2014 7:30 am
by Draco
Spacers on body side or bonnet side, just easier to do alone if you use body side.

Re: Lifting rear of bonnet for cooling?

Posted: Tue Jan 21, 2014 9:19 am
by Lukem
Does raising the rear suspension help the same? I always notice my car runs cooler when going down hill