Luggage box type 47 exhaust mods

[buzzer]

I thought I'd post some pics of the luggage box I have modified to fit with a type 47 exhaust. So if I use the car for road use I can take stuff with me.
Hopefully the picks are self evident.
I cut out the luggage box to clear the exhaust by about 40-50mm. Cleaned up the fibreglass round the edge and where I wanted to make repairs with a grinder flap wheel. I then used cardboard to make up the new shape. I taped up this on the inside as I wanted to glass it from the outside.
I used some car wax on the cardboard (which was shinny card) to act as a release agent.
I then very carefully laid up only 1 - 2 layers of glass not putting too much pressure on my delicate cardboard base. I waited for the resin to just get hard enough so it self supported and removed my cardboard. I left if for another hour then glassed up another few layers.
I also repaired some damage to the box while I was at it
Cleaned up with the grinder again filled and painted.
painted satin black and lined with black car boot carpet.
Then the fun bit which is a bit OTT, bit either you'll love or hate. I gold sized the engine bay side and gold leafed it  I will do the area around the exhaust cut out as well.

[jbcollier]

On my non-47, I wrapped the exhaust pipes, fit heat shields to the muffler and underside of the luggage box, and it still gets quite hot in there.  Any fresh eggs you carry will be fully cooked if you travel any great distance ;-)

[dakazman]

Can’t wait to see your build , I know your pain. The box is very thin and needs a good splice joint on both sides.
Will you add a heat shield , as JB mentioned ? A salvage yard has tons of them, all sizes and shapes yours for the taking. Use some standoff’s for mounting also.
Dakazman

[surfguitar58]

I am looking at this exact project in the next few weeks. Buzzer has set a high bar, but I will try to not embarrass myself. I was joking with Ray at rdent today about the heat buildup in the trunk/boot. He suggested baking bread back there and living up to the bread van moniker.
Tom

[surfguitar58]

BTW - Buzzer, can you fit 2 airline approved overhead carry-on bags in your new boot? That would be my goal.

[buzzer]

Exhaust is wrapped. But not the silencer. Did consider a heat shield as a sheet of ally attached to the luggage box, so will have a closer look. The reason I haven’t tried it  already is I didn’t have a suitable bit of ally to try it.
Airline bag bit, only one I’m afraid 😟

[EuropatcSPECIAL]

Nice job Buzzer

[Certified Lotus]

Nice work Buzzer!

My luggage box is cracked but repairable. I noted there was a metal plate installed on the underside where the muffler is located. With it attached directly to the fiberglass it’s more of a heat sink than a heat shield.

I doubt I’ll use the box much as I have enhanced my engine and purchased a complete performance SS exhaust sytem that I know will get hot. Plus that box must limit air flow in the engine area and that means the carbs are getting warm air at some point. And it adds weight!

[buzzer]

Thanks everyone.
I will look at shielding but also a very valid point on inlet temp. Where is it best to pick up clean cool air without body mods

[jbcollier]

Most/all of the cool air comes in through the front of the rear wheel wells.  The main problem is that there isn't a good way for it to flow out.  On a Renault equipped Europa, some air flows out the vents in the rear cover but quite a bit of it comes back in through the opening in the rear panel.  The 47's NACA ducts flow some air but, again, not much.  They won't even feed the carbs for example.  The best solution is to fit ducts that protrude from the body but that does come at a considerable aesthetic cost.

[Certified Lotus]

I’ve been thinking about the air supply to the carbs as the OEM install is a short flex tube to the air filter bolted to the back of the luggage box. Not exactly high volume cool air supply. Someone must have figured out a solution without building ducts into the body work. I have seen snorkels above the roof, but that is not an acceptable solution.

[Bainford]

BTW - Buzzer, can you fit 2 airline approved overhead carry-on bags in your new boot? That would be my goal.

Soft sided luggage is your friend. I place mine in an oversized ziplock bag to keep the engine smells from infiltrating the clothing too much.

[SwiftDB4]

47 style NACA ducts don't get much airflow, but at least source cooler air. I have a separate rear deck with snorkel that I use for track days. Has pressured airbox and adds about 500 rpm on straights.

[buzzer]

Impressive another 500rpm not to be sniffed it.
 I intend to register mine for HSCC production class. the car was raced in production Class in the 70’s
So that means generally no body mods.
Cool air generally is an issue not just for the engine but rear std brakes too.
So a lot of the cool air enters in front of the rear wheels by the fuel tanks then?  Should that opening be enlarged then? The other thought would be to close them off and flat bottom the engine bay but that would not be good for heat, improve aero but cook the engine. I wonder if there could be subtle tricks on the underside to encourage airflow.

[jbcollier]

Short of a snorkel or scoops, directing air through the chassis to the rear would work very well.  It would/might take air flow from the rad so carefully ducting would be required.