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DaveP
26th November 2018, 21:09
Hi all,
If you have not seen my build thread you will not have seen my Tribute Kobra with a twist.
I have had the bonnet scoop deleted (as they say somewhere) and so the air flow above the engine has less option to escape.
I’ve had the car painted and will be using it soon again. If I was concerned about the heat what would be a good way of deflecting/reflecting heat?
Underside of the bonnet is flow coated (grey not black) if that makes a difference to what would stick.
I’m not overly concerned but better safe than sorry etc
Dave

redratbike
27th November 2018, 16:36
The adhesive gold foil stuff

DaveP
29th November 2018, 20:38
Cheers.

Will look at suppliers

Dave

Lucky@LeMans
29th November 2018, 22:09
I really don't think you will have a problem. The Z3 didn't have a vent and the slot in a Cobra bonnet isn't big enough to let much heat out when the car is at a stand still. When your on the move the air flow through the front grill and over the engine will take most of the heat with it.

DaveP
30th November 2018, 06:59
I really don't think you will have a problem. The Z3 didn't have a vent and the slot in a Cobra bonnet isn't big enough to let much heat out when the car is at a stand still. When your on the move the air flow through the front grill and over the engine will take most of the heat with it.

Thanks. After getting it done I’m paranoid about issues. I drive it home Monday so picks on my build thread will follow.

Dave

Car photographer
16th December 2018, 13:30
would exhaust manifold heat wrap stuff help?

DaveP
16th December 2018, 15:56
would exhaust manifold heat wrap stuff help?

it might do yes. There is a gap above the beemer straight six and the bonnet so i will take a look. Now that it has been painted i was a bit paranoid. I bet I am worrying unnecessarily.

will keep an eye on things during the winter and look at options in the spring.

Dave

Nostromo
16th December 2018, 19:43
Instead of deflecting or reflecting the heat away, what about ducting some more in? Just a thought...

DaveP
16th December 2018, 20:12
Instead of deflecting or reflecting the heat away, what about ducting some more in? Just a thought...

Good point. But dammit I have spent time cleaning up the front and having less intakes. It does have a dirty great mouth grill though so I could see how to influence how that comes in if required.

Thanks for the suggestion

Dave

Dpaz
19th March 2019, 20:24
Is the radiator masked around the sides so that the air has to go through it and not around it?

DaveP
19th March 2019, 21:20
Is the radiator masked around the sides so that the air has to go through it and not around it?

Hi, it is not as such no. But given the mouth is the only inlet most would go that way. Will take a look next time it’s out to see if I can direct it more so.

Dave

Dpaz
20th March 2019, 07:56
The air goes through the rad, then round the edges and back in. Turbulence. Mask it off and you make a cleaner airflow through the engine room.

Welshkiwi
20th April 2020, 05:31
Hi Dave P, not sure whether you sorted the heat scenario, however just for info for all I fitted the original z3 bonnet heat blanket using self manufacturer or clip fittings. Reduced the heat that amassed into the bonnet significantly and it is now cool to touch even after 20mins idling on the driveway....hope it helps someone.

DaveP
20th April 2020, 08:05
Hi Dave P, not sure whether you sorted the heat scenario, however just for info for all I fitted the original z3 bonnet heat blanket using self manufacturer or clip fittings. Reduced the heat that amassed into the bonnet significantly and it is now cool to touch even after 20mins idling on the driveway....hope it helps someone.

Thanks for the suggestion. As it has turned out so far my concerns have not been warranted. So far it cools well and I have not noticed any heat build up.

Purely panic attacking post an expensive paint job. 18 months later and no paint-grp issues to note.

Loving your build by the way.

Keep safe

Dave