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Old 09-18-2018, 06:25 AM   #91
equ
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Incredible... I've always loved the body shell, the handling and feel of the RX-8..
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Old 09-23-2018, 06:54 PM   #92
John V
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I got my engine brackets made. It took me pretty much all day Saturday to get them cut and tacked in place. It was a lot more difficult than I thought it would be. I think the first issue was that I made them out of much thicker steel than I probably should have. I bought 3/16" steel which is pretty hard to work with, especially since I don't have a professional tubing notcher. I could have made them out of square tubing but round is stronger for this application and well... it looks better.

Anyway, I started with a piece of 1.5" OD steel tubing and made a riser off of the engine mount on the subframe. I welded a bottom piece to it that I cut out of a flat plate of 3/16" steel. I drilled a hole in the bottom for the engine mount stud.

Then I notched another piece of tube to mate up with that vertical tube. This was tricky since the bracket on the engine is about three inches forward of the engine mount, and about an inch and a half up. I ended up having to tweak the notches I put in the tube quite a bit to get the angle right. Then I had to cut the other end of that tube so that it would line up with the engine plate. I cut an oblong hole in each plate for the tube to slide into so it could be welded from both sides.

Anyway... lots of words. Here is what I ended up with on the driver's side (passenger's side was too hard to get a picture of).



Ugly tack welds but my machine really struggles with 3/16" steel. On the other side I pre-heated the brackets with a torch which helped a lot and gave me stronger, smaller tacks.

I took the brackets to my buddy Larry who is an expert TIG welder and he finish welded everything. I was pleased that the gaps were all tight enough for him to TIG, and that the tacks I made had good penetration.





This week I'll clean these up and paint them so they don't rust, but I'm really happy to get this step done. The engine has been supported by a above-engine support bar and it's in the way of getting a lot of stuff done. Tack welding these with that bar in place was a bear. I ended up doing what I could from the bottom with the car on the lift, but access wasn't great under there either and I'm such a novice welder I'm nervous doing anything not on a bench.

Next up... transmission mounts and ... a turbo!
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Old 09-23-2018, 08:23 PM   #93
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Those suckers are long!
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Old 09-23-2018, 08:38 PM   #94
John V
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Yeah, about 5 inches long each.

I couldn't resist going out to the shop and making sure they fit correctly. Driver's side:



Passenger's side:

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Old 09-23-2018, 09:28 PM   #95
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I'm surprised by the black thing that it attaches to - in the first picture. Is it braced from underneath and I just can't see it? It looks so long that the torque would rip it off the frame.
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Old 09-24-2018, 05:35 AM   #96
John V
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Quote:
Originally Posted by rumatt View Post
I'm surprised by the black thing that it attaches to - in the first picture. Is it braced from underneath and I just can't see it? It looks so long that the torque would rip it off the frame.
The black thing is a factory Miata engine mount, and yes it's braced from below but will be getting another cross brace. The aftermarket subframe I'm using is not known for being super strong.
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Old 09-24-2018, 06:05 AM   #97
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Speaking of, are you going to gusset the engine mount arms?
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Old 09-24-2018, 06:47 AM   #98
John V
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Yes, but I need the turbo, manifold and downpipe first so I can be completely sure where things will end up. I should have all of that this week and I can start mocking all of that up.
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Old 10-06-2018, 06:37 AM   #99
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I made good progress this week. I removed all the emissions crap from the wiring harness. I made some brackets to fit the NC radiator and fan in the RX-8. Not planning to use the stock radiator, but it's convenient to be able to make off the shelf parts fit wherever possible. I got the input shaft of the gearbox cut down, which is required to work with my bellhousing (which is designed for an FC TII transmission with a shorter input shaft). I got the driveline angles correct by shimming the front diff mount, and I got the slip yoke and pinion flange for the 8.8, which means I can start building the driveshaft.

Today I spent most of the day wrestling with the intake manifold, which wants to share space with the ABS pump and the belt tensioner that replaces the belt-driven steering pump that I'm not using. Eventually I'll use an electric water pump setup as well but for now I'm just using the factory water pump. I do need to machine a spacer or find one from a Mazda 3 tensioner because the pulley is about 5mm inboard of where it needs to be to line up properly with the alternator and engine pulley.

The tensioner that came with my 2.5 actually worked once I milled off about 30mm of material from the mounting bosses to move it closer to the engine. The stock NC intake manifold is pretty restrictive and also doesn't fit with the engine straight up in an RX-8, so I got a used Moto-East intake and cut down the runners to move it closer to the head so it would clear the ABS and the fuse box. I relocated the ABS pump to under the master cylinder and re-routed all of the lines. I modified the Mazda 3 alternator, which sits low on the driver's side to make room for the turbo and exhaust plumbing, so it would clear the steering coupler. I spliced in the wiring for the alternator, and finished the battery routing. My hands were filthy all day so I didn't take any pictures of that stuff, but I did take a picture of the "finished" product.

I really want to get this thing fired before thanksgiving to stay on schedule but I need to pick a clutch and flywheel first...

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Old 10-06-2018, 09:08 AM   #100
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Awesome. There seems to be a ton of room up front, not so much on top.
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