magnumP5's RX-7 Build Thread

Talked to an exhaust shop. They can't do super-thick walled tube (up to 14 GA max) but they can do stainless. I was quoted approximately $300 if I used 409 SS and $600 if I went with 304 and I have to provide my own mufflers, flanges, etc. Leaning toward 304 SS due to the higher corrosion resistance.
Turns out this shop can't/doesn't do mandrel bends. My exhaust won't have many bends in it but I'm still not fond of using crush-bent tube. I'm having a very hard time finding a shop with the ability to do full SS/mandrel exhaust.
 
I'm sure you can buy mandrel bent ss exhaust tubing pieces off the interwebs and have them all welded-up with the flanges and what not. It won't be cheap or easy but it will be the way you want it.
 
I'm sure you can buy mandrel bent ss exhaust tubing pieces off the interwebs and have them all welded-up with the flanges and what not. It won't be cheap or easy but it will be the way you want it.

Yeah, that's basically what they told me. It's possible but factor in about 50% more cost and it wouldn't look as good with all the welds. I was kind of hoping to limit the welds to just the flanges and the mufflers. There's a few other local places I've yet to call so there's still hope yet.
 
Turns out this shop can't/doesn't do mandrel bends. My exhaust won't have many bends in it but I'm still not fond of using crush-bent tube. I'm having a very hard time finding a shop with the ability to do full SS/mandrel exhaust.


Mandrel Machines are very pricey and complicated. Doubt a local shop will have the ability. IMO, best option is buy pieces like Hat1018 said.
 
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is it just me or is it a little weird that the guy that owns the car has no idea his car is being featured in/on something? Nothing against you Jon. It's just weird.

that's how the interwebz works these days.
 
Mandrel Machines are very pricey and complicated. Doubt a local shop will have the ability. IMO, best option is buy pieces like Hat1018 said.
Looks like I'm going to be entertaining the crush bent option. The shop I'm dealing with is claiming very little diameter change and are even willing to bend some pipe for me to see. I'm hoping to avoid any bends over 15 degrees so hopefully any diameter reduction will be minimal. I figure in the end if I don't like it I'll go back and weld in mandrel bends. Now I need to order some flanges and gaskets. I also need to reinstall the rear swaybar and swap in the aluminum driveshaft so everything is in place like it will be when I'm done to avoid "surprises."

that's how the interwebz works these days.
LOL, at least they weren't claiming ownership (not that anyone would). If they'd have linked something from Facebook I'd have known but since I don't have many pictures of the RX-7 uploaded I guess someone just stumbled across this thread. So far no negative comments though!

Added another layer of wax (up to 6 now) to the shroud mold and started grinding off the remainder of the brackets on the oil cooler support. It looks cleaner already! I also ordered some PVA for the mold because I'm paranoid the fiberglass will stick.
 
Jon, you are going to make teflon jealous.
lulz... I waxed it again last night (7 coats). The PVA also came in so now I need to find a way to apply that. The recommended way is with a spray gun powered by an air compressor but I don't have one of those. It looks like I could brush it on but I'm going to try to put it in a spray bottle set to the finest mist possible.

So I've been thinking about this for my next mod: http://www.roninspeedworks.net/index.php?route=product/product&path=60&product_id=60. What do you guys think? Seriously though, I've been considering pulling the stock spoiler when I get the body work done.
 
The fact that the wing will "get the back of your car to go down when your girl won't", has me sold on it. 1169 bucks made me cring though.
 
15 degree bends? That's nothing. You might even be able to get away with packing it full of sand. Iv seen it done on DOM, but that's a procwss
 
Sure wish i could see pictures on my phone. I miss this thread :(
You're not missing too much right now. How's the truck going?

The fact that the wing will "get the back of your car to go down when your girl won't", has me sold on it. 1169 bucks made me cring though.
LOL, they're an interesting bunch. His FC is absolutely ridiculous even if it is a V8-swap. I may serious consider the wing later in life if I start competing in TT or something. It'd be pretty silly on the street. In preparation for that though I may just have the body shop remove the stock wing and fill in the holes. All my Mazdas have had spoilers of some kind so this will be new to me, haha!

15 degree bends? That's nothing. You might even be able to get away with packing it full of sand. Iv seen it done on DOM, but that's a procwss
This is an interesting idea. I'll talk to the shop and see what they think. It's weird because I've browsed through a bunch of pictures of their work and sometimes the diameter reduction seems huge and other times not noticeable at all. Once my flanges come in I have to figure out a way to get the car to the shop and the exhaust work will begin.

Hopefully tomorrow I'll be laying fiberglass. The plan is for at least two layers of mat with another layer in the corners and flanges for support. I'm nervious as hell I'm going to screw up. So much seems to depend on speed so I think I'm going to half the amount of hardener I use versus what I used on the fleece. Hopefully, if I DO screw up, I'll be able to pull off the fiberglass, re-wax the mold and apply PVA and start again.

The radiator/oil cooler inlet is as free of obstructions as I can possibly make it with the stock setup:

20130815_205817.jpg


And in order to deal with the no hood latch thing my Aerocatch hood pins came in a whole 5 days ahead of schedule:

20130815_211532.jpg


Depending how the fiberglassing goes and when I get the exhaust flanges I may start with the ducting. I think I have it all figured out now so I'm eager to get started. This has easily been one of the more frustrating aspects to plan.
 
The truck is good. Havent been able to update my thread or view your thread to its full potential because i can only browse the net from my phone.
 
The truck is good. Havent been able to update my thread or view your thread to its full potential because i can only browse the net from my phone.
Can't view the pictures through your phone? I have no problem using my S3.
I got the fiberglass laid over the weekend:

20130818_194255.jpg


It was harder to remove than I expected but the wax and PVA definitely did their job. As it's my first attempt it's nowhere near perfect but it should hopefully still work. I ended up using only two layers because I bought heavier mat. It just has to be able to hold the fan anyway. It was hard getting bubbles out because after laying about 1/2 the first layer my roller fouled up with resin and was pushing the mat around. If I did it all again I'd cut larger pieces of mat and do whole sections at once. Tonight I'll start trimming and sanding. If it turns out crap I'll just try again.
 
Not much progress. I've spent the last few weekends traveling and taking care of other things around the house. I have spent a little time sanding the fan shroud though. It looks like a custom exhaust will be in the works within a couple weeks; full 304 SS except the exhaust manifold, which is 321 SS. I spent some time Saturday getting the car ready by reinstalling a heatshield, the rear swaybar, and swapping in the aluminum driveshaft, which is larger in diameter than the stock one. Now I need to reserve a tow dolly to get the car to the exhaust shop.
 
It's official. The RX-7 will be leaving the garage for the first time since April 2011 next Wednesday!
 
Has it been that long? Dang! You've got a ton more patience than me and I respect that, buddy. As always, we're always eager for updates and pics. Keep it up!
 
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