in an effort to reduce underhood temperatures at slow speeds i elected to cut holes in the hood/bonnet. i had a look at lots of different vents and these were the ones that i considered the most suitable without major custom fabricating. here are pics of the install, who knows if they are in the right place for evacuating hot air at speed or if they will actualy draw air into the hood?? havent had a test drive and chance to verify anything yet! also i will need to rig a drip tray inside to divert rain away from the engine.

 

they are riveted in place and also some body sealer is aplied between the carbon vent and the hood. like it or lump it im afraid, no going back on this without another hood!

 

From an aerodynamic sense, yes, I think they'll do a good job of exhausting the hot air from the engine compartment and not draw cold air the wrong way. You can tape some yarn streamers to the to visually verify that air is flowing the right way.

Now whether the lack of an air exhaust is what's causing your overheating is a different matter. The limiting factor could be the cold air supply, or you may have some other problem. The proof will be in the pudding - let us know how it works.

As to the asthetics, well that's a whole 'nother can of worms.

 

Hi Nick

Very brave....and nice looking....dont worry about water entry...engines work fine with a little water...ever seen a Top Fueller with a bonnet lol

All the best Brett

 

Personally not my cuppa, but I've always loved ingenuity and variety. I think if it were I, I'd cut vents in the fenders.

 

Nick


Those front wheels just look the biz

And i cant get athem anywhere

 

Are you leaving them Carbon or painting them?

 

tony, im going to leave them in carbon as i think the black will balance nicely with the orange and the black sunroof blank along with the black colour of the wing. heinrich, i agree that this isnt the best looking solution aestheticaly and the vents i would most have liked are like pierre has fabbed for his 'fat bully' but that would have involved a lot more time and money not to mention the difficulty in repainting the bonnet to match the colour etc etc so im actualy quite pleased with my quick and easy vents

aerodynamics wise i looked at lots of pictures and it seems as if you would be hard pressed to go wrong with vent placement as the leading edge of the vent diverts air into the correct direction. but it also seems that placing the vent further back on the bonnett where its more horizontal will also assist. the position i chose gives maximium venting to the radiator i believe, its just about the same level as the strut brace. if i went any further back airflow to the vent gets stifled a little by the heads/intake.

stuart thats too bad, no you cant have mine either so dont ask! 255 up front is great, im anticipating 265 next time

brett, im sure a little water wont hurt but we are living in england...

 

Hi Nick

You get water through front anyway...also blown up from underside....all I would do with those vents is put a little mesh in them to stop debris....

All the best Brett

 

brett, yes i will also be adding mesh and the drip tray wont be too elaborate. conveniently the edge of the vent lines up with the strut brace so i will attach it to that and drain it off away from the dizzy caps and plug leads/ timing belt etc.

 

Hi Nick

If you are going to have a run off...it might have to be longer than you think...I see the point about missing the dizzies...but if the run off goes forwards...it may well get blown back up by aiflow or fans...you may have to run a pipe down the side of block/heads...towards ground....

Just a thought

All the best Brett

 

I like it. Also, where can I aquire a pair of those rocker panels???
Kevin

 

kevin, i have had loads of people ask about the sideskirts since putting them on.. these came from a uk company - demon tweeks and i think the pieces originaly are RH moldings in abs plastic. they are for a vauxhaul but i cut the ends off to shorten them and spent some time sanding in the 928 body contour. my favourite for the 928 is the straight and flat strosek panel with the rear brake duct, if i were doing it again. i like the vents too, i think they add more of an aggresive quality to the front. i should take some more pics tomorrow if the sun is shining - otherwise i will be improvising drip trays!

 

Nick


Dont worry i'll make do with my 8x18 for the time being on the front

 

Interesting mod... I would think that the only time you'll have to worry about water getting in is when it's not running. From the charts I've seen the pressure in that area at speed is much lower than the pressure at the nose... low enough to draw air out: