New custom exhaust system fabrication

[silver]

thanks for the clarification

[silver]

[quote="Lane"]
[quote="silver"]
1:  the header primaries don't actually line up with the exhaust ports, therefore even though they are roughly the same size, the air coming out of the exhaust manifold is actually blowing into the header flange rather then completely in the primary tube.
[/quote]

Mine looked OK in this regard - at least when comparing the header ports to the gasket.



[quote="silver"]
2:  the header bend radius are all too tight and therefore do not pass heat through efficiently
[/quote]

Good to know.  Is this theory, or has someone done some temperature measurements between the stock header and something other?

[quote="silver"]
3:  The o2 sensor is too close to the the exhasust ports and it's  getting too hot and doesn't accurately send information to the ECU.  This causes the car to run rich and wastes fuel.
[/quote]

Wouldn't the original ECU tune compensate (assuming they tuned a/f with the sensor in that position)?  Or is it suspected that the sensor reading goes totally screwy?

[quote="bolus"]
I think the idea of using a repackable exhaust should always be considered.  since the muffler on pretty much any solution is eventually going to get destroyed on our cars, a cheep fix would be a good one.[/quote]

Borla does have the million-mile warranty on their stuff.  Might just be high enough quality to last... we'll see.  Positron's still being together with 20 track days is good news.

[quote="silver"]
Or get a muffler with no packing and only 18 gauge metal baffles inside....that way there's nothing to wear out! [/quote]

It'd be nice to hear a muffler of that design on our cars, as I wonder if it would effectively suppress the hi-freq rasp.
[/quote]

Lane I  never saw your responses until tonight.

Here's some answers

I'm not sure what's up with the primaries matching the exhaust ports.....maybe I misunderstood Ray

Ray did do a LOT of temperature testing on the exhaust to see where the heat was getting stuck.......I wasn't there..........but why would he lie ya know.

It's suspected that the sensor reading goes screwy which leads to additional fuel being pumped into the system.....which is why I get way better gas mileage now....and that's fact on the mpg and opinion on the screwiness

My exhaust has no raspiness now, it sounds like an engine with a cam though lump lump lump lump  I love it.

Lastly..........I love borla too..great stuff.

[Lane]

Work has continued on the system since the initial install.


Took it back to the shop and a Cherry Bomb Vortex muffler was installed in place of the Borla (with the ability to be swapped very quickly as well).  This one has some baffling in it, and I wanted to try it to see if it reduced sound levels further.  Pic is after the entire system was Jet Hot coated.  But, because this new muffler looks a bit boxy compared to the rest of the lines on the car, I wasn't satisfied with how it looked.  I had all winter to figure out how to improve its looks and it would be the perfect opportunity do something here myself rather than letting the shop have all the fun.



I purchased some heavy-gauge perforated steel mesh.  Cut it up, bent a curve over the muffler, welded ends on it, and painted it with hi-temp header paint.  Put some threaded inserts into the muffler and attached it with screws.



Aaah, much better look in my opinion - even if most people may think it adds some Mad Max feel to it.  Adds some shape over the flat boxy muffler.  Plus, I can now accidently lean up against the muffler or put a hand on it without it being burn-level hot which is a bonus.  Now I just have to figure out how to integrate a brushed aluminum Ariel logo into it or something like that...

While this was being worked on, two additional o2 bungs were welded in and the sensor was relocated further away from the header collector to reduce the temps its subjected to.  I had to use an o2 extender cable and covered it with fiberglass heat wrap instead of the original foil.  Purchased and installed a Dynatech conical insert in the intermediate pipe to knock off a few more db.  When all was done, it ended up sounding very good.  Quieter during highway cruising, but a nice deep powerful tone under acceleration without covering up the blower whine.  Nice burble under decel also.  The only disadvantage is that this muffler is built like a brick sh*thouse and I would have preferred it to be a few pounds lighter.

There are quite a few more picture in high-resolution in my website's gallery here (page 2).  No sound clip yet, but I'll snag one shortly.

[NormLarson]

Lane, ... you have given inspiration to someone resigned to the Fortress look!  Any more pictures, please.

[silver]

VERY NICE Lane, I had a similar Idea making a cover out of sheet metal, then having it painted color matched to my body panels.........to cover up the BOX we have for a muffler

[Heywood-Yablowme]

Someone call me?   Lane,that looks fantastic,and is functional. Well done

[NormLarson]

[quote="Norm"]
Lane, ... you have given inspiration to someone resigned to the Fortress look!  Any more pictures, please.
[/quote]

OK, read that you already had pictures ...  Looks great!  Nice work.

[bolus]

Looks cool   :tu:  Not very mad max though,  you should add some barbed wire if you want more of a mad max look 

Oh, were did you get the material?  It looks just like the grille material I used but grilleguy.com has flaked on a lot of people here so I'd like to have another source to recommend. 

[maverick1]

Nice work Lane...I like the mesh look.
The only thing I don't like about your exhaust is that darn flex pipe.
Ever since mine blew up at California Speedway, causing lots of heat damage to wiring and the masterlube....
I just don't trust flex pipes any more.
In my opinion slip joints are the safer way to go.
So many Atom owners have had big problems with the flex pipes.
Good luck, I hope yours holds up.
cheers

[silver]

on a custom system you really don't need the slippy pipe OR flex pipe, the only reason they used it was to make up for minor differences between cars.

[Lane]

Thanks everyone for all the kind words.

[quote="bolus"]
Not very mad max though,  you should add some barbed wire if you want more of a mad max look 
[/quote]

Oh, now you've got me thinking.

[quote="bolus"]
Oh, were did you get the material?  It looks just like the grille material I used but grilleguy.com has flaked on a lot of people here so I'd like to have another source to recommend.  [/quote]

Everyone selling grille material to use on the front end of a car seemed to have only fine mesh aluminum, and often woven wire and not perforated.  I found it IMPOSSIBLE to find a small quantity of medium gauge perforated steel (more easily weldable with MIG than alum) with holes that aren't tiny. I ended up buying speaker grilles off of eBay from this guy.  Bought extra to put some of the material in front of the radiator, or horizontally under the nosecone to create an autocross cone deflector.

[Driver]

I thought immediately that the material looked like you robbed a Mac Pro of its grilles.

[Terry Kennedy]

[quote="Lane"]
I found it IMPOSSIBLE to find a small quantity of medium gauge perforated steel (more easily weldable with MIG than alum) with holes that aren't tiny.[/quote]

If you have a Lowes nearby, take a look at the Steelworks stuff. This is a set of bins 6-8 feet wide that hides somewhere in the hardware aisles. There's a large assortment of bar and angle stock as well as flat sheets and expanded sheets.

Home Depot also has a Steelworks section, but (at least around here) they carry a much smaller selection than Lowes.

Menard's also has something similar - I don't recall if it is Steelworks brand or not (and I don't have any Menard's near me).

[Wmcmanus]

Interesting that you would use speaker grill to cover the Atom's uhhh... loud speaker!  It looks great.  You did an excellent job at concealing the seams.

[1965Cobra427]

[quote="Lane"]

[/quote]



Nice!