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Mostin
29-04-2017, 11:24 AM
Hello all.

I'm on the look out for a spare bonnet if anyone has or knows of one.

Many thanks.
Mostin.

islandman
29-04-2017, 11:59 AM
You're about a year too late as Dirk had my spare last year. Also curious, why are you after another one, your looked great with the reversed Nostrils?

sorry to hijack the thread, but I'm looking for a spare rear end also (any mark or condition considered).

Mostin
29-04-2017, 12:43 PM
You're about a year too late as Dirk had my spare last year. Also curious, why are you after another one, your looked great with the reversed Nostrils?

I want to try to change the Nostril size / shape to see if it help the heat to vent from the front rad.

I've got vents under the bonnet but they might not be big enough & space is tight so there are limits too how much I can open them up.

With a spare bonnet I can mess about with the mods & change it out to test it while still keeping my Nova on the road.

Cheers.
Mostin.

islandman
29-04-2017, 01:22 PM
I vent mine with no bonnet holes, purely from the two large outlets on the top under the bonnet with large gap mesh so no airflow restrictions.

Try an experiment and take all your meshes off the holes you have first and drive it like that first to see if there is a noticeable difference

Mostin
29-04-2017, 02:20 PM
Do you have any photos of the hole locations / sizes.

Is it the area in front of the steering box & the opposite side?

Thanks again.
Mostin.

Buffy
29-04-2017, 08:17 PM
Mostin
Search through Davids photos, there are lots of under bonnet pics, even on his website .

jim73vw
29-04-2017, 08:27 PM
Hello all.

I'm on the look out for a spare bonnet if anyone has or knows of one.

Many thanks.
Mostin.

I have 2 - one plain in good nick, and a scrappy nostril one.

Both in the loft.

https://www.flickr.com/photos/99001802@N00/sets/72157661225683542

BlueNova
29-04-2017, 09:50 PM
I have 2 - one plain in good nick, and a scrappy nostril one.

Both in the loft.

https://www.flickr.com/photos/99001802@N00/sets/72157661225683542

Hi Jim, if Mostin doesn't want the scrappy nostril one, could you pm me a clearer photo of its problems and maybe we could sort out a deal?
Alistair

islandman
30-04-2017, 01:07 AM
Do you have any photos of the hole locations / sizes.

Is it the area in front of the steering box & the opposite side?

Thanks again.
Mostin.


OK, looking at the photos I actually have 4 main holes :

1) One large one under the battery box (The cut was tidied up later), the battery sits slightly raised above this hole as it rests on a metal frame for the radiator so technically air can escape from here. Potentially sucked out due to the low pressure created as the air rushes past under the front undertray. My undertray doesn't go all the way to the frame head as it was cut off by the previous owner (probably due to the wrong chassis length previously and holes not lining up)

2) Two large ones on the top of the bulk head. These are covered with large gap mesh

3) One smaller round one (which I forgot to fill prior to paint) on the passenger side. This has an aftermarket cover with fine mesh that probably doesn't make much difference in terms of airflow.

http://i713.photobucket.com/albums/ww131/islandmanhere/Underbonnet%20holes_zpsxyk7j79w.jpg (http://s713.photobucket.com/user/islandmanhere/media/Underbonnet%20holes_zpsxyk7j79w.jpg.html)


And here is the bonnet filled up with gubbins and mesh covers over the holes.


http://i713.photobucket.com/albums/ww131/islandmanhere/Underbonnet%20holes%20with%20mesh_zpshfyckhdv.jpg (http://s713.photobucket.com/user/islandmanhere/media/Underbonnet%20holes%20with%20mesh_zpshfyckhdv.jpg. html)


And for completeness of the solution here is the modified front undertray with the holes that allow airflow into the bonnet and onto the radiator. All airflow around the radiator is blocked so it has to pass through the radiator matrix.

http://i713.photobucket.com/albums/ww131/islandmanhere/IMG_5432_zpsdpjdxszk.jpg (http://s713.photobucket.com/user/islandmanhere/media/IMG_5432_zpsdpjdxszk.jpg.html)

http://i713.photobucket.com/albums/ww131/islandmanhere/IMG_5433_zpsjg3wwsxj.jpg (http://s713.photobucket.com/user/islandmanhere/media/IMG_5433_zpsjg3wwsxj.jpg.html)


Another option, If you want to prove conclusively that any temperature rises are a result of airflow versus airlocks simply take the bonnet off all together and take it for a long run. I drove mine around with no bonnet when it was off being painted for two days.

jim73vw
30-04-2017, 07:00 AM
And here is the bonnet filled up with gubbins and mesh covers over the holes.


And for completeness of the solution here is the modified front undertray with the holes that allow airflow into the bonnet and onto the radiator. All airflow around the radiator is blocked so it has to pass through the radiator matrix.

http://i713.photobucket.com/albums/ww131/islandmanhere/IMG_5432_zpsdpjdxszk.jpg (http://s713.photobucket.com/user/islandmanhere/media/IMG_5432_zpsdpjdxszk.jpg.html)

http://i713.photobucket.com/albums/ww131/islandmanhere/IMG_5433_zpsjg3wwsxj.jpg (http://s713.photobucket.com/user/islandmanhere/media/IMG_5433_zpsjg3wwsxj.jpg.html)


Another option, If you want to prove conclusively that any temperature rises are a result of airflow versus airlocks simply take the bonnet off all together and take it for a long run. I drove mine around with no bonnet when it was off being painted for two days.


I think that is a very sensible suggestion. I only have two bonnet nostrils and a slot cut behind the pump to access steering rack and my radiator isn't an ideal angle but no cooling issues. I'm sure air also escapes through edge gaps etc. Obviously air does need to escape but most often the issue is air not going through the rad. Can't access my pics easily from Stoneleigh hotel but my lower bumper solution was very similar to David's with the ducting modified to duct straight to the under bonnet area and any gaps sealed to stop air bypassing. I filled any gaps/joints with silkaflex once final fitted.

jim73vw
30-04-2017, 07:07 AM
I think that is a very sensible suggestion. I only have two bonnet nostrils and a slot cut behind the pump to access steering rack and my radiator isn't an ideal angle but no cooling issues. I'm sure air also escapes through edge gaps etc. Obviously air does need to escape but most often the issue is air not going through the rad. Can't access my pics easily from Stoneleigh hotel but my lower bumper solution was very similar to David's with the ducting modified to duct straight to the under bonnet area and any gaps sealed to stop air bypassing. I filled any gaps/joints with silkaflex once final fitted.

Some of mine under construction

2153

2154

Mostin
30-04-2017, 04:19 PM
Dave / Jim many thanks for your help. There's a couple of things to try.

Jim nice to see you today at Stone's. We'll sort something out about the smooth bonnet. Great stuff & many thanks.

I'll be looking at taking my Nova out with no bonnet to see if it's the lack of venting as well

Cheers.
Mostin.