Saturday, July 12, 2014

Dual Exhaust Completed


Since I didn't post one with the last post, here's a photo of the car with the front bumper re-fitted using metal brackets as the factory intended.


A few weeks ago, I relocated the fuel pump to the fuel cell bracket via a 90 degree full flow -8AN feed and a hose clamp. The feed fitting holds it in place and the hose clamp will stop it from vibrating the fittings loose. It's now much louder, however that also means I can hear if it struggles (I couldn't easily before as it was isolated from the cabin by its mount and the rubber hose I'd wrapped it in).

This is also a much better gravity feed than the 5/16" ID hose I was using previously.


My xForce 2" straight through mufflers turned up in the post.


Not stainless, since that would mean I'd need more wire for the welder! (not to mention cost more!)


I borrowed a ute from work and picked up some 2" exhaust tube from the local ABS outlet.


I cut up the original 2.5" exhaust we made temporarily back in this previous post: http://www.e21build.com/2013/04/its-alive.html and welded the flange to the flex joint.


Then, with the help of some spare axle stands, positioned the 2.5" hotdog resonator kindly donated to the project by Tim Knowles (cheers mate!)


I cut the original exhaust up each side of every bend, this way I could test each bend in numerous orientations to make it fit as well as possible.


Here, the flex pipe is connected to the hot-dog. Unfortunately the hot dog burned through quite a few times, I assume due to the carbon build up as it was a used item and hard to clean inside because of it's construction.


I had the assistance once again of Shaun Harman; always willing to lend a hand on any metal-related projects. Note the pipe bender I intended to use to form the 2" pipe for the tail section.


Another two bends joined together, this one a pair of slight offset kinks (one larger than the other) to get the pipe up and past the differential housing without fouling a halfshaft or the tailshaft.


Shaun fabbed a mount and welded it to the pipe. The mount bolts to the standard front position saddle fuel tank mounting locations (since the saddle tanks are no longer fitted to this vehicle)


Flange cut at the correct angle and welded as close to the floor of the vehicle as possible.


Center section completed.


Started splitter from 2.5 to 2x2" by cutting two sections of 2" pipe at 45 degrees, joining as a 90 degree then cutting the corner off.


Weld penetration on the inside.


Closer


2.5" adaptor peice made - perfectly round on one side, finished on the belt sander and cleaned of burrs


And a matching oval on the inside.


Welding the two together.


Close up of the weld. Not perfect, but functional. I'm noticing how much easier it is to work with clean metal (well duh!)


Shot showing the inside of the splitter.


Here you can see I tried to press bend a piece of pipe rather unsuccessfully. I decided to pie cut the pipes at a small angle. Here I've already cut the splitter pipe at the same angle to get the curves started.


Lots of short, random length peices cut at the same small angle, finished with file and belt sander and cleaned with acetone.


All layed out.


Here's a rough idea of what I'm going for.


Tacked the splitter to the flange, then tacked a number of pieces to the splitter.


This one is pretty much ready for the muffler!


Here you can see the pipe which goes back down past the diff toward the other side of the car. I removed and fully welded occasionally so I didn't end up with the whole thing facing the wrong direction.


Here's the completed setup. The pipes currently mount by use of a hose clamp around the pipe just prior to the muffler on each side, which is placed through the tie down loops. The top of the mufflers sit against a rubber that's factory above the normal exhaust mounts. I haven't welded mounts onto the pipes as yet.


Stainless 2"-2.5" angle cut 8" exhaust tips from ebay look the goods.


From behind - click this image for a higher resolution version - you can see the bottom of the pie cut section showing under the vehicle.

Whoops - here's a video:


Tuesday, July 8, 2014

Bumper brackets

I've noticed when taking passengers in the vehicle, the front left wheel (passenger side here in Australia) is scrubbing.

A closer inspection shows it to be scrubbing on the front bumper, which seems to come within 5mm at static height (compared to 10+mm on the RHS) of the tyre when turned ever so slightly to one side.

I believed that this was caused by the front bumper, which is not mounted with the standard mounts that normally go from the chassis rail to the bumper; and whose standard location would put them through the end tanks of the radiator. 



As a result, the only thing that was holding the bumper on were the side bolts through the guards; I figured this was causing a bit of warpage and getting the guard too close to the wheel.


So, I took the mounts, grabbed a spare piece of thick walled scrap steel RHS and tack welded the mount to it to maintain it's overall length and shape, then marked out the position each side of the radiator.




And cut.


Welded on enough extra to clear the radiator,


A bit more.


Test fitted, trimmed.


Another shot showing the location of the radiator. If it wasn't for the BBS front bumper, I'd need custom aero to conceal the radiator. Perhaps that's not such a bad idea....



The front bumper appears to have a pretty big bulge/dent on it. I don't remember putting it there - perhaps the car was in a minor fender bender in the past? Might explain the guard clearance issue? Thanks to Nas80 on the forums over at bmwe21.net I now have a list of dimensions to check against the suspension/chassis rail points to verify if the vehicle is straight.


Nothing a pile of hammers won't fix.



Completed brackets.

Bolted the front bumper back on, also trimmed the BBS bar where it had been rubbing for good measure.



End result, car looks the same and guard looks still too close to the tyre.

I need to measure the radiator support bracket I made; from memory it was a tight fit to install - so it's possible it's pushing on the top of the guard causing the bottom to flex inwards slightly. Nothing a grinder can't fix (or a washer or two/some shims, if it's actually too narrow!)