The first muffler in mock-up. It'll sit a bit higher and more forward but this gives you the basic idea.

Tomorrow morning's video drop covers getting this version to what you see here. I'll post the link in this thread.

Looks great, such a nice shape. Is that stainless, would look fine polished. Good thing I saved this picture

Click to view attachment

Here's the latest iteration of the the latest update. No, it won't ever end.

https://www.youtube.com/watch?v=kpIo6-XdMIw

Pics of progress for those who simply can't wait until the next video is released.

@Dave_Darling Dave - I hope this level of visibility meets with your approval.

Other side fitting underway. @Andyrew Andrew - Sorry, upright is always better!

Heat shielding for trans?

Now THAT is downright sexy...

This is the best one yet!

Videos are getting better and better!

Love this project!

@bkrantz - A few folks have asked about this. Here's a shot of the clearance. I may add a shield.

I figured you had something in mind.

--DD

Fantastic...

The car is leveled and the passenger side muffler is set to the same position as the driver side. As you can see by the gap in that last 90 degree tube, I'm nearly there. One final trimming and it'll be good to go.

Couldn't resist a pic of things at this stage of completion. I should have it all wrapped up, including the exits, in the next post.

Ready for final welding and some exhaust tips. Nearly there.

That is really cool looking. It looks like it will work well, more so it will sound just as good. My brain wants to know about the temps you expect in the trunk. And are we in for some awesome fresh air intake design. Spooky cool dude

I sent you a PM.

Best Bob B

sorry doubble post

@Shivers - Yes, you are. But no promises. I'm entering uncharted waters, at least for me. But I'll do my best to keep you entertained as I learn what is and what is not possible!

Martin was At The Red Barn today and we focused on getting the exhaust tips fitted and final welded.
They haven't been trimmed to length but I'm super happy with this new exhaust. It met the targeted goals:
- symmetry that pleases my eye? Check
- mufflers all but invisible? Check
- transmission totally visible? Check

I did want the center exit exhaust but this one has it's own sort of style points. Less elegant, more brutish, which certainly fits the build. It's not as "Porsche" as a center exit but it does a lot to add to the "that is a wide 914!" look.

On to the next thing I decide to do!

And the latest video to get you current on the exhaust fab.

https://www.youtube.com/watch?v=88CoEduwtGM

I love the look and can't wait to see the finish length of the tips as well as hear it run.

You could add exhaust cut outs before the X and have the cut out exits in the center...

You've got plenty of room.

It would be LOUD!

Your mounts are very well designed. They look like they should work fine. Very tidy.

I'd add some type of expansion connection to both sides before the X section.

Might be as simple as slip tubes and springs or true flex sections on v-bands.

I think the temperature swings that the system will go through will over stress that x section and it will fail without some type of stress relief.

Sure looks pretty like it sits...

Edit: Love the new intake. On the LARGE size!
You need a built motor to go along with that!
13:1 with nearly 300 degrees of duration.
600+HP will be attainable through that intake.
You just don't have a car that can apply that power to the ground.
Car will need to weight 4K plus to make that work well.

You're designing a tire destroying apparatus...

https://www.youtube.com/watch?v=z4nDae578cQ

@SirAndy @markhoward - Hey, guys, you know I'm all about METAL!
Speaking of which, @buddyV Robert stopped by yesterday and poo-poo'd my initial rear mount. Constructive critisism is great because if forces me back to the design board and (IMO) I invariably come up with something I like more. In this case, it's a folded sheet metal bracket that has WAY more style points. Me likee! Plus, I'll maybe back it up with some mesh, like on the rear panel.
Thanks Robert!

That's a bunch stronger as well!

Rear mount fully welded, including a set of underside gussets.
Martin was by today and we noodled out a design for the exhaust tip hangers. He's back to his shop (lathe and mill, which I don't have) to whip up the needed parts.

This one is a bit different. You've heard me mention Martin and all the help he's been on my builds. Here's a bit of an intro and a peek into his background. Talk about a man with passion and skills!
And if you're at all into slot cars, this is a must see! Plus, you'll get a teaser about an episode on his experience designing/building ProStock drag bikes. Enjoy!

https://www.youtube.com/watch?v=p1imXSqo7dw

That just transported me back to the late 60's when we would go to the Slot Car Track in San Leandro on East 14th Street everyday and race our cars.

Back to the exhaust and it's all done but the outside hangers.

https://www.youtube.com/watch?v=gGtX3jBaRro

Sweet. I can't wait to see the final tip length and hear it run.

Embarking on another "I wonder if this will work" project. These are Nash Metropolitan doors, one of which I cut up. Will it work out? Place your bets now!

For whatever reason, as I was moving the doors, I noticed the shape and thought, "I wonder if I could use that as the center section of a rear valance?"
It'll take some work, but I think I can. Sort of diffuser-like and a pretty neat shape.
I'd love to be able to say I used part of a '59 Metro on my build.
We'll see how this goes.

Back to necessary things. Here's the outboard muffler support in place. Not too noticable from the engine compartment side and totally invisible from the rear.
Yes, it's single-shear but the other end is mounted in pretty pliable rubber so I'm not worried.

I like it

I like where that is headed.

The second I saw the metal from the Metro doors I knew what it was. I had a buddy that had a metro way back. Great idea for the rear valance. Dual out flared valance it's going to be nice. You know the thing is, you do your best to design an exhaust and until it cycles through high heat and cools a number of times you are not 100% sure what it is going to do.

@technicalninja Rick had men mentioned
“I'd add some type of expansion connection to both sides before the X section.

Might be as simple as slip tubes and springs or true flex sections on v-bands.

I think the temperature swings that the system will go through will over stress that x section and it will fail without some type of stress relief.”


--- I had thought it may need some kind of Bellows because I remember what my 74 turbo 2.0 did after running it around very hard and the exhaust was glowing red and would bend a bit.I did have bellows on its SS custom system. ---

I guess if it has a problem in road testing it you will just rework it.

Anyway, your ideas as a designer and fabricator are fantastic and your work is as good as anything I have ever seen.

Best Bob B

A quick errand this morning with everything done, including tips trimmed to length. I'd swear it's quieter, too.

Can we see a full-on side shot please? To my eye (and it could be the angle) they look a tiny bit long.

@Cairo94507 Michael - These are the same length as the dual asymmetric I just replaced. I'm going to live with them a while. Easy enough to shorten them if I decide that's what needs to happen.

Hi Chris- Now that I see them from the side they are fine. Sorry, they looked longer in the other angles.
Cheers,
Michael

Back on the intake. I fabbed a test piece to verify the plenum base plate spacing measurements. Lots of stuff to work out but it's a start.
Remember, whatever gets build, the goal is a clear top plate so you can see the stacks. Fingers crossed this actually works!

I decided to make a heat shield for the new exhaust. I was going to try and make it from aluminum but figured it'd take quite a while, I'd screw up a bunch of material, etc. So I opted to do one in carbon fiber.
First I need a mold and figured why not use it as an opportunity to learn a new skill.
So I did a bit of research and ended up with this:
- place a suitable sheet of ABS in a 225 degree oven until it "goes soft"
- drape it over the shape you want to copy
- press, weight, form and hold it in place until it cools enough to hold the shape

I was a little hesitant with the heat, what with it being my first time, and the first go didn't work out - the ABS wasn't soft enough to form a couple of the tighter areas.
The cool (!) thing is I just popped it back in the oven (don't tell my wife), bumped the heat and let it bake until I could easily fold up a corner.

Then it was: pull it out, drape it on the exhaust and quickly form it as best I could. I used a bodywork sand bag to weigh it down while I worked downward force everywhere, as best I could. Once it was clear it was no longer formable, I removed the sand bag. Here's what it looked like at that point:

Lift it off and BAM! One exhaust heat shield mold.

Pay no attention to the shape around the edges, the final part will be trimmed to look nice, be symmetrical, etc. Next, it's on to some carbon fiber layup.

It was a fun afternoon. I love adding to my skills tool box.