Babalouie's 911 - start on p7

[Babalouie]

I was a little bored tonight, and decided to have another go at mounting that sender. That little L-shaped bracket was a little plain, I thought :D

The original bracket was made out of 2mm aluminium, which is massive overkill, so this time I'm using 1mm ally, which I like, since it's thin enough to cut with snips, and so you don't make a huge mess with the jigsaw.


You probably know where this is going...


Yup....guilty as charged


It's been a while since I used these...


MUCH better


More befitting a hot rod 911 :D

[31GUN]

Much more perfessional. I approve of this product or service.

[Captain_Slow]

Having had a very frustrating night last night at my panelbeating course where I couldn't cut, hammer, or weld for shit consider me jealous of your abilities.

[Ben Wilson]

Have you got a linisher? They do a great job of smoothing the cut edges on aluminium.

[Babalouie]

'shore do...

[31GUN]

Have you tried that with no gloves on?

[fat910]

'shore have.

[Tils]

fingerprints= gone, computer keyboard use= painful?

[jzx83]

Aaaaaaaah, that's better.

Can't believe you went to that much effort. When I posted I didn't realise you can't even see the bloody thing normally.

Not that I wouldn't be quite likely to do the same in your shoes.

While we are tying up loose ends, How's the Hako Tacho? :p :D

[Babalouie]

A long time ago, I bought this: a 100-cell DesignTek cat from the UK.


It looked super nice, but unfortunately, when I tried to install it, it didn't fit...it was a half inch too short. Two of the joints on the exhaust are quite unusual. Instead of a conventional bolted flange, you have this olive, which goes between the 2 pipes (which have bellmouthed ends) and then that big bolted clamp goes over the joint.


So it sat on the shelf for many months, until I took it to my friends at Castle Hill Exhaust, where they cut the cat pipe, and expertly TIG'd in a half inch section.


The first step of installation, is to remove all the heat shields from the old cat.


Which isn't easy, because of these horrible things. Instead of using self-tapping screws and speednuts, the 911 has these stainless fastneners which are a little bit like a hybrid of a speednut and a regular nut. The nut has a square base, and the idea is that the stainless clip prevents the nut from turning as you loosen the bolt from the other side. The problem is, stainless threads have a habit of jamming with age, and so what happens is the nut jams, and then tears the crap out of the clip (which isn't strong enough to deal with it). So then you have to find some way of getting it off with pliers, etc. It's a real nuisance and a lousy design.


But eventually the old cat is out, and it's a lot bulkier than the new one. Also you'll spot that I'm taking the opportunity to put a new O2 sensor in....and if you're looking at this pic, thinking that the brackets for the heat shields don't seem to be the same, well, hold that thought


The old cat was in good shape, with no obvious signs of the substrate being damaged (they can go crumbly with age).


But the new one clearly has a more open "weave" to it, and should be more free-flowing.


So I fit up the new O2 sensor, and bolt up the stock heat shield, in readiness for installation...


...where it immediately fouls the (plastic) shrouding over the lower cam cover. I'm not sure if the stock one did this as well, or if this is just a sign that the DesignTek cat reallY *was* made on a plasticine jig :D


But when life gives you lemons....you get your fabrication on


The new shield needs to have several bends in it, and a find that a neat home made way to create nice folds is to sandwich the sheetmetal between two planks of wood, and then use a second plank of wood to carefully fold over the sheetmetal, using both hands and all your weight.


And the finished product...the front of the shield needed to curve inwards to avoid fouling the plastic shroud, so I made a piecut there and folded in two sections of the metal, and riveted in a short strap of metal behind it to hold the shape.


Back into the car it goes (and replacing as many of those horrible oem fasteners with nuts and bolts as possible)


And we now have a nice gap between the cat shield and the plastic shroud.


I do think it looks a little goofy, though, with the heat shield being so much bigger than the cat...I reckon it'll look better if I cut the heat shield mounts off the cat, and make new mounts which allow a more form-fitting shield to be made.


But for the time being, it has made it noticeably louder, with more of a hollow bark to the exhaust note which isn't objectionable Power-wise, maybe I have to drive it more, but on the cruise into work this morning, it did seem to be a little sprightlier.

[Rezz]

I wish I had a car that was worth spending that kind of time restoring... great work as always.

[clutch-monkey]

awesome work babs!
my aftermarket exhaust was annoying as hell to take on and off - scott cut the heater boxes off for me though, made it a lot easier. the manufacturers had forgotten to make plugs/holes through the heater boxes like the oem units, to let you get a socket onto the exhaust manifold studs.. *shakes head*
also had to lengthen the tips so they came out of the correct place on the rear valence, although i may have to undo that now with the different bumper.

[Babalouie]

Someone wanted to know what it sounded like:


Specs are 100-cell metal cat, primary muffler bypassed with straight pipe and stock secondary muffler.

[BigMuz]

When you make those little brackets on the linisher- first trace around a small washer so the radius is exactly right.

It makes the bracket look 100 times neater.

[Babalouie]

Good idea!