New bonnet design in the works..

98kellrs · Post by **98kellrs** » Mon Aug 06, 2007 10:25 am

For those who have not been reading my diary section (and I dont blame you, it's quite dull atm!) I thought i'd let ya'll know about a lil project I've got on the go at the moment.

Basically I have a spare bonnet and am trying to turn it into a lightweight track day bonnet that will hopefully copy the style of this:

So far I have washed the bonnet, and cut out all of the strengthening beams and dual layers, I've also cut two slots down the sides of the center section which will allow me to give it the raised profile. Here's the interior all stripped out:

And this angle shows the rough appearance at the moment:

This is going to be filled in with fiberglass, to look something like this ((TaDah!):

The idea being that it will help remove hot air from the engine bay, thus keeping the engine cooler, and also will push the air over the windscreen wipers eliminating vibrations at high speeds and hopefully being a little bit more aerodynamic!

Hopefully I'll start getting her glassed by tomorrow night, and then it's down to painting it!

Any suggestions, ideas, insults welcome!

Ettore Bugatti · Post by **Ettore Bugatti** » Mon Aug 06, 2007 11:24 am

Satin black paint please

Instead of filling the gap with GRP I would rivet some wire mesh in the bonnet.
Easy, quick solution.

JohnTurbo · Post by **JohnTurbo** » Mon Aug 06, 2007 11:37 am

insults welcome

Manx Tw**!! Stick your three legged flag thing up your tailpipe!

Nice effort. How much does it weigh with all that stuff removed?

robkendall · Post by **robkendall** » Mon Aug 06, 2007 3:44 pm

JohnTurbo wrote:
insults welcome
Manx Tw**!! Stick your three legged flag thing up your tailpipe!

Nice effort. How much does it weigh with all that stuff removed?

i was gonna go with:

it looks like youre bonnet was ripped apart by a child with a large can opener

....but i like yours better!

is this for the paris blue car yeah?
i would do a complete lime green bonnet with the center part black....matt black which you can then emblazon with any sponsor logos etc!
(it is supposed to be for a track car after all!)
rgrds
rob

98kellrs · Post by **98kellrs** » Mon Aug 06, 2007 3:50 pm

Ettore Bugatti wrote: Instead of filling the gap with GRP I would rivet some wire mesh in the bonnet.
Easy, quick solution.

Easy and quick yes, but rigid, no. Something solid will have to fill the gap as the grp is quite elastic and doesn't like being lifted up! It should be easy to do without compromising weight too much, I was thinking about cutting slots down the side of the infilling though and riveting mesh over them but just an idea.

I'm glad you said satin black, 'cos that's what I was thinking about!

Although i may just do the raised bit in black, and get the two side panels resprayed same colour as the rest?

JohnTurbo wrote:How much does it weigh with all that stuff removed?

I don't know yet to be honest! There are still a few things to be shaved off, and some construction to do, but I think overall it will only be a matter of lbs. All the grp I removed weighed next to nothing but i will do a comparison weight between my current bonnet and the new fancy one to test!

aibast · Post by **aibast** » Tue Aug 07, 2007 6:49 am

I'd do something different. Maby a airintake that directs cold air behind the engine to cool the turbo a bit better.

98kellrs · Post by **98kellrs** » Tue Aug 07, 2007 11:29 am

hehe all well and good mate, but i don't have a turbo!

I'm going to spend this afternoon prepping her for glassing tonight hopefully!

robkendall · Post by **robkendall** » Tue Aug 07, 2007 12:28 pm

hiya ryan

are you doing away with the hinge mechanisms too?
just go for 4 pins to hold it down?
(one on each corner of course lol)

how are you going to accomodate the airflow from the front...leave the front standard? its obviously good enough for the cold air flow for the rad, but wont that stop a lot from flowing over the block?
(i understand the concept of what youre doing to release hot air from the back....)

maybe some kind of sealed pan under the engine bay....would then only really have one exit through your vent?
rgrds
rob

DaKyy · Post by **DaKyy** » Tue Aug 07, 2007 1:11 pm

You'll need a snowcap with that

98kellrs · Post by **98kellrs** » Tue Aug 07, 2007 3:27 pm

robkendall wrote:hiya ryan

are you doing away with the hinge mechanisms too?
just go for 4 pins to hold it down?
(one on each corner of course lol)

how are you going to accomodate the airflow from the front...leave the front standard? its obviously good enough for the cold air flow for the rad, but wont that stop a lot from flowing over the block?
(i understand the concept of what youre doing to release hot air from the back....)

maybe some kind of sealed pan under the engine bay....would then only really have one exit through your vent?
rgrds
rob

For the time being it's just gunna be the two pins at the front and keeping the hinges as I'm only here for another week before I'm away until christmas. But yes it will be converted to a 4 pin - lift off bonnet.

Eventually yes i'm planning to seal off the engine bay so that air will only come in through the radiator at the front, and will escape when heated via the bonnet. But i'm not entirely sure how well this will work. Do you think that the cold air rushing in will stop the air escaping out the back?

I'm not sure whether it's better to allow more air into the engine bay, or whether to try and restrict incoming air as much as possible with the obvious exception of the radiator. Given time restrictions at the moment though everything will stay as standard at the front until at least christmas (she'll be stored in a garage on axle stands anyway!)

@Dakky, 'fraid not my friend. The grill is getting filled in and smoothed over as i'm thinking that forced air coming in will block off the low pressure air trying to slip out (and i never really liked the intakes there anyway

).

Any suggestions from you aero-boys (i know there's a few of you on here!) as to how I can sort out my (air) fluids?

Ettore Bugatti · Post by **Ettore Bugatti** » Wed Aug 08, 2007 10:00 am

I was more thinking in

when I said wire mesh. This is a bit stronger and you have more engine bay ventillation too.
If you look at the rwd hotrod 480's they have a raised bonnet too.

I think the air should only passed the radiator and after that it should go outside the engine bay. A 480 has a liquid cooled engine not an aircooled one (bloody beetles) so no air is needed in engine.

pol · Post by **pol** » Wed Aug 08, 2007 10:08 am

Cool.

Is it ready yet is it ready yet is it ready yet?!

pol

robkendall · Post by **robkendall** » Wed Aug 08, 2007 11:57 am

Ettore Bugatti wrote:A 480 has a liquid cooled engine not an aircooled one (bloody beetles) so no air is needed in engine.

it doesnt hurt though to reduce the ambient temperature in the engine bay.
liquid cooled is fine, but the block still gets bloody hot too....so a couple of degrees cooler could make a huge difference?

regardless of function, i quite like the form anyway....is cool that someones experimenting and not just sticking with the tried and tested 480 shape....
rgrds
rob

98kellrs · Post by **98kellrs** » Wed Aug 08, 2007 11:57 am

Ettore Bugatti wrote: I think the air should only passed the radiator and after that it should go outside the engine bay. A 480 has a liquid cooled engine not an aircooled one (bloody beetles) so no air is needed in engine.

Yeah that's what I was thinking! Not sure how is best to get rid of the air from the rad yet, but i'll figure that out later!

And sorry Pol, but you'll have to wait until Sunday at least before it'll be finished!

JohnTurbo · Post by **JohnTurbo** » Wed Aug 08, 2007 1:15 pm

This is it. Cool isn't always better.

If i, say, got a 480 turbo rad, and plumbed it in to a fiat 750cc panda, and rigged the thermostat to be always open, then went for a 70mph run - the oil would not be hot enough to lubricate properly.

The rad is matched as well as possible to the scale of the heat it needs to expel.

A good example here is my sister's old 2cv - it has a plastic cover that stops airflow into the engine bay partially for the cold winter months.

98kellrs · Post by **98kellrs** » Sun Aug 12, 2007 4:04 pm

Wellll the project is now complete! I'm happy to report a 3 degree reduction in engine temps, 7 kilograms worth of weight lost, and a vent that extracts engine bay heat VERY well!

There are a lot more pics in my diary section here:
http://volvo480.dragons.org.uk/forum/vi ... 224#133224

But here's a teaser..

Roo · Post by **Roo** » Sun Aug 12, 2007 4:14 pm

That looks pretty neat. Would be really good in the cars blue imo.

98kellrs · Post by **98kellrs** » Sun Aug 12, 2007 4:18 pm

Next time I have a few hundred quid spare that's top of my list!

robkendall · Post by **robkendall** » Sun Aug 12, 2007 6:23 pm

nice one ryan...looks good!

dont listen, dont listen....blue? bleurgh!
limegreenlimegreen!!!!!!

rob

98kellrs · Post by **98kellrs** » Tue Aug 14, 2007 12:34 am

haha cheers Rob, I'll have a think about the lime green for when I do the job properly!

Now all i gotta do is beef up the brakes and find a way of getting some more umph!