99 E36 M3 LSx Build

[Schitzo]

Awesome work on the headers, Chuck. How many hours do you have in just the #7!! Did you consider using a donut?

[ckpitt55]

Good progress!! Can't wait for more updates man!!

True definition of one-off headers right there. That is how my first set came out 10 years ago and is why I could never make a case to reproduce them...way too difficult to reproduce the complex fitment!
Your #7 solution is beautiful and will save you much grief down the road from melted plug wires. I absolutely love your workmanship and attention to detail!

T

Awesome work on the headers, Chuck. How many hours do you have in just the #7!! Did you consider using a donut?

Thanks gents

Robert, #7 wasn't as painful as it looks - it fell together fairly quickly. I considered using a donut but wasn't a huge fan of the cost....I couldn't find anything in stainless under $120 so figured I'd give the pie cuts a try.

[Nightridere3695]

Want to build a second set for me? I think I'm going to need the 1 7/8 over the 1 3/4 that I wave now for my 403 build

[ckpitt55]

Want to build a second set for me? I think I'm going to need the 1 7/8 over the 1 3/4 that I wave now for my 403 build

I'm not prepared to make copies at the moment but I'm also not opposed to the idea. Shoot me a pm to discuss.

[ckpitt55]

Decent bit of progress over the past few weeks.

My previous #7 routing looked goofy to me so I reworked it a bit and tweaked a few areas for improved clearances.



Motor mount clearance - I will be wrapping the isolator with adhesive backed reflective tape.



With my engine positioning and thicker valve cover gaskets required for the rockers to clear the covers, the stock brake booster wasn't going to work. After a bit of research I bought a dual diaphram booster out of an E34 540i on ebay. There are a couple problems with this booster - 1) the pedal clevis is too narrow to fit the e36 brake pedal and 2) the mounting studs are too short to make it all the way through the firewall and e36 pedal assembly with enough thread engagement and 3) the increased height puts the booster in extremely close proximity to the plug wire connection on the #7 coil pack. There's room on the coil bracket to shift the #7 coil forward slightly, so that's what I did. Not really difficult problems to solve but things to overcome nonetheless.

E36 booster (left ~ 11" dia) vs. e34 540i booster (right ~ 9.5" dia)



Clevis difference - (e36 top vs. e34 bottom). I couldn't figure out a way to disassemble the boosters and just swap the pushrods cleanly so I just cut of the e36 clevis and welded it onto the e34 booster.



Resulting clearance to #7 primary (good thing I moved it)



Clearance to valve cover with the thicker yella terra gaskets



The booster needed to be clocked 180 degrees from the typical e36 position so the check valve didn't interfere with the valve cover. The M3 master seemed to bolt up fine. For vacuum line routing, I picked up a 90 degree check valve out of an E36 318 along with a length of bmw 12mm vacuum hose. This also matches the port size on the back of the FAST 102 intake, so no need for an adapter.



Still have to relocate the pedal travel sensor but that can wait. Figured I'd share these details because there wasn't a whole lot of info out there when I bought this stuff. While it's not direct bolt in, it's not really that hard to make work either....hope this helps someone.

With booster clearance sorted out I put some additional tacks on the header and pulled it out of the car.



Primaries pulled apart and cleaned



44 welds in total.....time consuming would be an understatement.



Some of the welds......they're 20 footers. Consistency needs a lot of work but there's only one way to get better.



Put back in the car for final test fit and tacking the flange on





Inside of flange welded - I tried to keep heat input to a minimum, skipping around alot to spread out the heat and hopefully reduce distortion.



Sanded and ported



Numerous articles / forum posts I came across recommended tig brazing the exterior fillet weld with silicon bronze, so I figured I'd try it. It's a lot more forgiving than stainless (in terms of elongation properties) and is supposed to help prevent stress cracking as a result of thermal expansion. This stuff was tricky to work with - doesn't flow nearly as nice as stainless with the added challenge of trying not to melt any of the base metal into the braze joint. Washing too much steel into it embrittles it and makes it crack. I bolted the flange up to a big piece of aluminum to act as a chill block to try and keep flange distortion down - I left it bolted up until everything was cool and it still warped a bit since space constraints (and my inexperience) forced me to go pretty slow. It pulls flat pretty easily when bolted down though so I'm not too concerned about it, not that I could really do anything about it now anyway.





Back in the car.....still fits!





Driver side finally done!

Now time for the passenger side:

My fbody starter was a dud, so since I needed a replacement anyway I figured I'd get a mini starter to help with clearances and potential heat soak problems. I opted for a powermaster 9509 starter. It's ~1.5" shorter than the fbody fwiw....not really any smaller in diameter. I'll be wrapping this in a thermal blanket to help protect it.



Plenty of room on this side (forgive the surface rust....body work is next)



Second collector taking shape











Positioned under the car



Spent months on the drivers side. Progress after 2 days on the passenger side lol. A little more work to do before it's ready to weld but it's close...some things may need to move because I forgot to bring the dipstick up to check clearances, but probably another week or two and this will be done.



More to come soon. Thanks for looking.

[Schitzo]

Man, that header turned out great! I'm planning on doing the same with my flange. How much heat did you end up using? I imagine it was tough trying not to melt the tube all the while melting silicone rod.

[ckpitt55]

Man, that header turned out great! I'm planning on doing the same with my flange. How much heat did you end up using? I imagine it was tough trying not to melt the tube or the while melting silicone rod.

Thanks Robert. I'd say I was using about 60 amps on average - hard to say because I had the machine set higher and was regulating with the pedal. I was using 1/16" filler rod - you could probably get by with less amperage if you used .045" filler (which I may try for the passenger side).

A couple tips if I may offer them:

-make sure the metals to be brazed are sanded clean to bright shiny metal. the chromium oxide layer on the stainless can cause problems - my flange wasn't perfectly clean in a few places and it was kind of hard to get the braze metal flowing. Welding on AC might help with this but the cleaning action balls the electrode and causes the arc to wander all over the place. For that reason I just welded on DC.
-use a sharp electrode, initiate the arc and camp out for a few seconds with low amperage to "preheat" the area before you try adding braze. Trying to add rod immediately results in the end of it balling up and making a mess.
-once you get a puddle going increase your arc distance a little while keeping it centered on the filler rod. Arc length isn't as critical to keep super tight since you're not trying to penetrate the base metal - just seemed to help reduce the amount of steel that got melted on the edge of the puddle.
-the stuff flows almost like solder when in a molten state and is affected by gravity much more than welding steel - it was kind of challenging to braze uphill / downhill and end up with a consistent bead profile.

In hindsight I wish I would have been a little more patient and done some practice flange joints but I didn't have any material so just went for it.

Edit: managing flange distortion - the flange was flat before doing the exterior brazing. Afterwards the ends had pulled back a little - the 1.5" thick aluminum block wasn't enough to keep it from pulling. If I were to do it again, I'd either use a spare cylinder head as a heat sink or experiment with shimming the center two ports of the flange up before bolting it down, or both.

[Schitzo]

Thanks for the tips. I'll definitely do some practice runs before welding the header itself. Currently, I set my machine at 40 amps (no pulse) when welding the tubing so I might go with the 0.045" filler rod.
I just finished mocking my driver side header; time to start cutting metal.

[ckpitt55]

Thanks for the tips. I'll definitely do some practice runs before welding the header itself. Currently, I set my machine at 40 amps (no pulse) when welding the tubing so I might go with the 0.045" filler rod. I just finished mocking my driver side header; time to start cutting metal.

Best of luck. I did the rest of the primary welds with ~50 amps with .045" filler. Gonna try some .035" filler and see if I can reduce the amperage some while maintaining penetration.

Looking forward to updates on your build.

[ckpitt55]

Got the passenger side just about done, only thing left to do is weld the flange on inside and out, finish welding the collector spring retainers and install 02 bungs. I'm going to do the flange exterior fillet weld with 347 stainless instead of silicon bronze this time....I'm having a hard time keeping the braze metal from cracking even with low amperage.

The only thing that sucks about the fitment on this side is that in order to maximize ground clearance, the header will need to be dropped to change out a starter motor in the event that it fails. I was able to maintain a good amount of space around it and it will have a heat blanket as well, so hopefully I will never need to do this.

Anyways, here's a few pics.

Fitup complete....really can't cheat at this step. Takes an inexperienced guy like me forever to do it - countless trips up and down out of the car sanding things to fit just right. It's an exercise in patience but it helps prevent excessive warpage during welding that would otherwise hose your final fitment once you try to assemble everything (ask me how I know)





Pulled apart and cleaned up with the scotchbrite belt



purge / welding setup





I welded this side with .035" 308 filler and ~42 amps vs. .045" and 50 amps on the driver's side. Amazing what a difference those small changes made to the overall heat input. Consistency still needs a lot of work but I'm much happier with how this side turned out. Much less overall heat input, better color, more consistent bead profile and penetration.



I bought a spare flange and practiced some welding with .045" 347 filler, around 80 amps here focused on the flange then washed up onto the tubing. 347 seems to be a lot more colorful than 308 - pretty rewarding to weld with



How she sits currently



In other news, I cut out my front and rear windshields to prep the chassis for going up onto the rotisserie to finish seam welding and reapplying undercoating to the undercarriage. Rear glass came out fine but I cracked the front just as I was cutting the last corner.....turns out the knife I was using wasn't long enough to get all the way through the urethane and I got a little too impatient....oh well. It wasn't OEM glass anyway.





More soon gents, thanks for looking.

[ckpitt55]

Haven't updated in a while....busy with work, school, and trying to prepare my shop for winter. Installed a ceiling, added insulation, sheathed / tyvek's the exterior walls, installed a new man door, and the list goes on.

I've been slowly chipping away at the rest of the exhaust system. I was inspired by Allmotor's build and his link to David Vizard's article on zero loss exhaust systems, and decided to try designing the rest of my system based on those concepts. Allmotor term box design was really well thought out, so I did my own variation of it borrowing a lot of the construction methods. This one came out to be ~ 12.0L - it's 24" long and approximately 9" wide. Fit up inside the tunnel pretty nicely.























It's hard to tell in the pictures because I suck at photography but the term box is flush with the floor pan, ~ 1.5-2" between it and the driveshaft.

As for the rest of the system, I'll be going from the headers into 3" flex pipes, high flow cats, then into the term box. Then out back I'll be stepping down to dual 2.5"s, using two borla s-type mufflers and a pair of dual exhaust tips I got from Redtail Performance. They fit the cutout in the bumper perfectly - I just have to mirror it on the other side. No idea how loud this is going to be - these mufflers are the same ones used on corvette s-type systems and they sound great to me, so I'm going for it. If I need to change it up I will.



Hoping to get the exhaust system finished then I will be switching gears to body work. More soon.

[bimerok]

These Borlas look the same as on my cousin's C5. They do sound amazing!

[ckpitt55]

Haven't had a whole lot of free time but since the last post I've started doing a bit of body work. Decided to order my wheelset and get cookin on the fender flares, among other things.

I like the oem-ish look of welded on flares so picked up some e46 front fenders off of rock auto - these were from a 2002 330i sedan.



I went with 18x9.5 et 35 apex arc 8's with 275/35/18 rubber. Could have went with a larger wheelset, but I wanted to stay square and knew I'd be limited by what I could run up front while still maintaining a reasonable amount of clearance / bump travel, especially with such a tall tire. The handling improvements of a square setup, being able to rotate wheels, and striking a balance between wheel package weight and tire cost / selection were all considerations.



Fast forwarding a bit to the flares cut out and mocked up on the car. Here is the stock flare:



e46 flare



Additional clearance up front prior to rolling is ~1"







Ready to cut



After lots of patient sanding / fitting



Welding in progress. Skipping around, tacking, then grinding, and hammer / dollying in between rounds of welding to keep warpage to a minimum. Then keep going until there's aren't any gaps between the welds.



Fitment with front bumper. Wasn't sure initially if I was going to splice into the existing fender or just continue the e46 fender all the way down to the bottom. Opted for the latter so added that piece back in.



Shot from the rear



Same process for the other side..



You'll notice I cut into the body lines....for some reason these flares are not as defined as others I have seen and for that reason require a larger transition area to blend smoothly into the fender - perhaps that is the difference between pre and post-facelift e46 fenders? I tried to replicate what I cut out by bead rolling a profile into the flare with a set of shoulder dies. After a couple test samples I found one that seemed to fit nice



I'm sure there are much more refined ways to do this, but I'm not a metalshaper...just pretending to be lol



ANYWAY....here's some test fitment pics. Don't mind the red stuff - it's dychem layout fluid that I'm using to sight the panel. A quick scuff with 80 grit will reveal all your high and low spots that you can go in and (try to) correct with a hammer and dolly. Trying to get it as straight as possible in metal so I don't have use a sh*t ton of filler.

MEAT....it's what's for dinner.



This is with a 17.5mm spacer and a small amount of camber. The spacer is necessary for the tire to clear the coilover spring perch. I'm using TRM coilovers, and their camber plate assembly is insanely thick - approximately 68mm from the top mounting surface to upper spring perch. Vorshlag is putting together a much more compact camber plate assembly for me and I'll be switching from the 7" TRM spring to a 6" Hyperco spring. Hopefully this combination will allow me to raise the perch to be above the tire and buy more clearance inboard. I have full clearance lock-to-lock at ride height up to about 1" of travel but with more compression the clearance kind of sucks. I'm going to be on 600# springs though so I have no idea how much travel I actually need. Probably not a whole lot but I'm shooting for as much as possible for now.



Checking clearances. The fender ahead of the tire where it comes back to meet the bumper is a pretty nasty interference point at about 1.5" of suspension compression. I'm going to see what I can buy here with a fender roller, hopefully I'll be able to push that out some. If that doesn't work I will section it as necessary and pull it out off the tire. As mentioned, I'm not sure what I'm actually going to need because I'm never going to see much travel with 600# springs up front.

Bimerok, Maynor, Inflame, Fair, and anyone else I may be forgetting who has messed with flares and wide tires that sees this - could you comment on how much clearance you were able to achieve with your setup up front? Kind of worried about clearances under compression while turning.



Waiting for parts to show up before continuing with that.

Anyway, here's a couple pics of flare fitment at the rear of the car. Will probably be running a 20mm spacer back here.





Clearance increases over the stock flare seem to be much more significant than they were in the front - I measured ~2" at the furthest point before rolling.



The flare ahead of the tire is going to need some work to get it to fit tightly against the body though - need to think about how to approach that. It requires too much force to make it flush, if I tried to weld it like that it would just warp like crazy.



That's all for now, more to come soon.

[bimerok]

Hey nice work man!

It was fairly long time ago that we did these flares on my cousin's track car and he also sold the car since then... From what I remember he ran some kind of wide offset with 9" or 9.5" wide rim and a spacer, using 255 NT01's. Like you have discovered with the fronts, the area where fender meets the front bumper was a little on the tight side, but nothing dramatic. I can't remember that there was too much rubbing in that area, but if there was, not a lot. Oh, now that I think about it, he might have bent the little trip piece that goes right above the bumper slightly out to gain more clearance, but not a lot.

The bigger issue was in the rear, on the top of the rear bumper area. That section was rubbing a bit more. I think it eventually "adjusted" itself to where it almost did not rub under compression

[Inflame]

At the front, I rub at the exact same point as you do. I rubbed at the very front edge of fender flare and I rubbed on a mounting pointing within the wheel well just ahead of the tire when the wheels were pointing IN on their respective sides. I let the tires rub away at the plastic flares and I hammered away at the inside, cutting out material, bending, etc so the tires would stop rubbing. I still rub against the body at full lock when tires are point OUT. We have the same wheel setup except I'm 17". I have a 15mm spacer.

At the rear, I rubbed at the back edge of the flare under compression and at the very inside top edge of the tire.

275/40/17 NT01's.

Epic progress Keep up the great work!

[ckpitt55]

Hey nice work man!

It was fairly long time ago that we did these flares on my cousin's track car and he also sold the car since then... From what I remember he ran some kind of wide offset with 9" or 9.5" wide rim and a spacer, using 255 NT01's. Like you have discovered with the fronts, the area where fender meets the front bumper was a little on the tight side, but nothing dramatic. I can't remember that there was too much rubbing in that area, but if there was, not a lot. Oh, now that I think about it, he might have bent the little trip piece that goes right above the bumper slightly out to gain more clearance, but not a lot.

The bigger issue was in the rear, on the top of the rear bumper area. That section was rubbing a bit more. I think it eventually "adjusted" itself to where it almost did not rub under compression

At the front, I rub at the exact same point as you do. I rubbed at the very front edge of fender flare and I rubbed on a mounting pointing within the wheel well just ahead of the tire when the wheels were pointing IN on their respective sides. I let the tires rub away at the plastic flares and I hammered away at the inside, cutting out material, bending, etc so the tires would stop rubbing. I still rub against the body at full lock when tires are point OUT. We have the same wheel setup except I'm 17". I have a 15mm spacer.

At the rear, I rubbed at the back edge of the flare under compression and at the very inside top edge of the tire.

275/40/17 NT01's.

Epic progress Keep up the great work!

Thanks for the input gents, I appreciate it. The 275/40/17 appears to be the same rolling diameter as the 275/35/18 I'm running, so I'll probably just see what I can buy with a healthy fender roll and move on.

[Nightridere3695]

That's the rear tire I'm going to try to run 275/40-17 Mickey Thompson drag radial....

[ckpitt55]

That's the rear tire I'm going to try to run 275/40-17 Mickey Thompson drag radial....

Assuming you're going to add flares you should have absolutely no problems running that size....plenty of room for more tire out back.

Body work is progressing slowly, but it is progressing. Since last time I've continued work on getting the front flares finished and started moving onto the back.

I had started mig welding the front flares on but ran into some problems when trying to metal finish / hammer and dolly the weld out. Mig makes the metal extremely hard and pretty unresponsive to shaping pressure. So I cut the flare out and tig welded another one on.



Tight fitup required to prevent burn throughs. Not much room for error since I was only using .023" filler wire.



Flare welded on. Did this with ~25 amps and moving as quickly as possible. I started welding at the center and worked my way outwards in both directions, doing about 1" at a time. Doing it this way prevents metal from being "trapped" in between weld beads and reduces the chances for distortion.



Working on metal finishing the panel - not much filler will be needed. If I was any good at this, no filler would be required at all.



After that was finished I reinstalled the fender and tried to maximize clearance in front of the tire where it joins the nosepanel. I rolled the fender heavily here, cut the end of the nosepanel and bent it outwards, and also slotted the holes in the bumper mount so I could push it out further and get everything to line up.



Same thing done on the opposite side







To maximize clearance on the inside of the wheel, I modified my TRM coilovers with some vorshlag camber plates and 6" hypercoil springs (stock length was 7"). This combination allowed me to move the spring perch up a considerable amount. You can see the difference in camber plate stackup height here



With the fronts in pretty good shape, I moved onto the back. As I mentioned previoiusly, the car had been hit at some point in its past and the passenger side rear quarter was replaced. The body shop did a pretty lousy job and rust was forming in between the seams. I removed the quarter to clean it up and will be reinstalling a new one.



Some of the seam rust below. Details are important folks. Use your chassis wax, weld through primers, epoxy primers..whatever you need to do to keep this from happening.





Thankfully it was all surface rust and cleaned up pretty well





Sprayed with weld thru primer for now until I can get around to epoxy priming it.



With that more or less resolved I moved on to starting to mockup the flare itself.

Clearancing for rear bump travel - this is the minimum necessary to rear full bump travel but I'm going to wait until I get the new quarter to segment this further and bring it out to match the flare seam.





Cleco pinned the quarter back on temporarily for test fitment. The 18x9.5et35 wheels I'm using required about 30mm worth of spacer to fill out the flare. Lots of room for a wider tire but I want to keep a square wheel setup to start out with so I can rotate tires and promote better turn-in characteristics. Time will tell whether or not I need more tire back there but I'm not going to worry about it now. By my math, this is the same wheel position achieved on the vorshlag alpha car which had 17x11 et 23 wheels with 315/35 tires, so I will definitely have the room should I need it.





Trying to capture a couple different perspectives of it because its kind of hard to judge the fitment from one angle.



Kind of difficult to photograph but here's roughly how the car will sit



My hope is that these in progress pics help other people thinking about doing this job themselves. This mod definitely isn't new and there's plenty of before / after pics but not a whole lot in between, especially with the rears.

In other news, I've been working on making copies of my motor / trans mounts. If anyone is interested let me know. I have more information on a blog page here: http://getoffmylon.blogspot.com/p/blog-page_4.html

[ckpitt55]

Started getting serious about the rear flare on the drivers side this week.

I ran the edge of the flare on a shrinker a bit more to get it to match the contour of the body as well as I could. Much better than it was.



The biggest problem area with the flare is where it meets the bumper - it tucks in pretty significantly and causes some pretty big interference problems with the tire.



Cleco pinned on and starting to pull out the rear



I tacked the rear edge and ran a fender roller on it as much as I could. Couldn't really put that much pressure on it until I tie the inner layers back in to support it, but it made a big difference in terms of clearance. Also pictured is the little bracket in progress that will push the rear bumper out to match the flare.



I want it to look like the car came this way when I'm finished, so I started working on provisions to allow the side molding to continue through the flare like it did stock. Shouldn't be too difficult to do.



With a good start on the flare I turned to figuring out what to do with the inner layers. Due to the shape of my flare, it's tying in the body line pretty far up. I stared at the inner layers for quite a long time trying to figure out the best way to seal everything up and pretty much what I settled on was cutting and hammering them out to meet the cutout for the flare and welding the layers back together there.





I looked at it a bit more and realized trying to seal up / protect all those individual cuts from rust would be more difficult than just having one continuous piece of metal in there with one continuous seam, so I cut them all out and will be adding in a new piece of steel to seal that up. This also gave me better access to further shape the inner-most layer of metal and beat it out to meet with the quarter. It's pretty heavy gauge (16 ga, I think) so it requires quite a bit of persuasion. BFH is the tool of choice here.



Lots of hammering



The inner layer pretty much hammered out to match and ready to weld. Just need to do some trimming and get some weld-thru primer to try and protect everything that I don't have access to once it's all sealed up. Will probably also be getting some 3M Rust Fighter to spray into the internal cavity once complete.



In other news, the slr mini kit came in and I installed that. Very nice components / machine work. I was drawn to this primarily for the geometry correction benefits, along with the increased steering feedback and 40% ratio quickening that results from shifting the tie rod pickup point closer to the center of rotation. This also produces increased steering angle, but I doubt I will be able to utilize much if any of that due to the tire sizes I'm running. I'm setting this car up moreso for autox / road racing anyway so I don't care about having 8 million degrees worth of steering angle.



That's all for now. Continuing to gear up for the upcoming body work marathon. I think I'm beginning to see the apex of the project - I think I'm pretty much done cutting and removing stuff. Looking forward to sealing everything up and starting assembly.

[Inflame]

Awesome progress man, very high quality. I hope to have a work shop similar to yours once I find a house!

[kc jr 54]

Awesome work throughout this thread.

[ckpitt55]

Still alive and kicking here gents. It's been a little while but I've been busy. Work on the fender flares continues, along with some other general shop updates that will pave the way for more progress in the upcoming weeks.

I spent a little more time tweaking my front end setup a bit. My initial steering clearance was pretty poor after installing the SLR kit with the standard e36 arms and wheel spacers to set the wheel position in the flare. I would have needed ~ 30mm worth of rack limiter per side to prevent the tires from hitting the frame rail when turning. After some research / playing around in solidworks to project potential differences in the geometry, I test fit some e46 control arms (~25 mm wider per side than e36 arms) and removed my wheel spacers. Without getting too technical, this component tradeoff bought me a lot of additional clearance and dropped my necessary rack limiter to ~8 mm per side. To offset the increase in camber from the longer control arms, I simply swapped my camber plates left to right to give me more positive range adjustment to bring the wheel back within a more streetable range.







Removing the wheel spacers brought the wheel in much closer to the spring perch, but since I reconfigured the coilover for use with a shorter 6" spring it looks like I will still have clearance.





With the front end more or less wrapped up, I turned attention to some shop related updates necessary to allow me to proceed forward with body work. I intend to try and paint this myself....well as much as I can anyway (I don't have the pockets to afford paying someone else to spend the time / attention on it that I would want them to), one of the first things I did was build a water trap for my compressor to help give the air a chance to cool down enough for the water to drop out as condensate. The hope being that it would help my filters be more effective at pulling out water and reduce the moisture content of the air. Not really that critical for regular air tools but really important for painting.

Bought a bunch of 1" copper tubing and started soldering. The velocity of the air through larger tubing is slower, therefore more time for heat to be dissipated and water to condense.





Pressure testing the completed assembly....doesn't leak!



Mounted on the wall behind the compressor



Seems to work pretty good. A heat exchanger between the compressor and tank would have been better but we'll get there eventually.

From there I moved on to start prepping parts and gathering supplies for getting parts under some epoxy primer. I ended up going with SPI epoxy which seems to get great reviews everywhere on the internet, sands easily, and is also a hell of a lot cheaper than PPG dp40 series primers ($180 for sprayable 2 gallons vs. ~$140 for sprayable quart). Should be a great foundation for corrosion protection as well as the rest of the paint job.



My buddy's neighbor heard about what I was doing and offered to let me borrow a spray booth he had put together for when he painted his car, so I jumped at the opportunity. He put together this wicked blower motor setup that houses some standard furnace filters to capture overspray from going outside. The motor drives the blower via pulley so that there aren't any spark sources in the path of the flammable vapors that are passing through....nice to know I won't catch myself or my project on fire! Big thanks to him and my friend Jon for helping me haul all this stuff to my shop.



The frame is made out of some 1" electrical conduit tubing...just slides together like legos. The walls are made of the 4 mil poly sheeting that I cut / taped to the frame as necessary.



Here's the more or less completed exterior, with filters placed for the intake to make sure I'm minimizing the amount of dust being drawn into the booth.



I rigged up some ducting for the blower outlet to allow me to vent the paint fumes while keeping the garage door most of the way closed to lock heat in the shop (it still gets down to 40s and 50s at night here in PA).



On the inside, I used some conduit clamps to put up 2x4s for mounting my filter / regulator, and also keep the hose off the floor. I don't have a picture but I also hung up a couple spare 4' light fixtures on the opposite wall to get some additional light in the booth as the ceiling lights are pretty diffused by the plastic.



With the booth ready to go I got some panels ready to shoot. I started by removing the unknown finish (not OE bmw since this panel was replaced on the car) on the quarter I pulled off using aircraft paint stripper.



After a few hours of scraping / sanding / welding holes shut / grinding / cleaning, it looked like this:



With that ready to go, I switched back over to the rear flare I had started. I'll preface this section of the post by saying that lots of guys talk about how much work goes into doing this, but it's hard to appreciate it unless you do it yourself. I spent a lot of time thinking about how best to seal everything up - and ultimately chose to cut out a lot of the factory metal and make a patch panel out of a single piece. Less welds = less chance for water infiltration and corrosion.

Anyway, innermost layer of the wheel-well hammered and welded to the quarter.



Fast forward a couple steps, and I have a patch panel formed and trimmed up to fill the hole that I had cut in the wheel well. (Cleco pins are awesome)



Fast forward a couple more steps, and I got everything prepped for spraying in the booth with epoxy primer.



Quarter in epoxy



Wheel well patch in epoxy



- - - Updated - - -

Had to break the post up into 2 parts

After the epoxy cured, I got the patch panel back in the car:



Here's the little piece I added to seal everything up near the molding support



Next I bonded the inside seam of the panel in with some 3m panel adhesive, and sealed the holes left behind from the cleco pins with some stainless rivets, which also served as clamps to hold the panel securely as the adhesive cured.



Next, I started the process of welding the outer edge of the panel to the quarter.





With the patch panel in place, I could finally start the final trimming / fitting of the flare. As mentioned I wanted to integrate the factory molding to go into the flare like stock, so a lot of effort / time was spent getting that to look decent (or try to anyway).



Another closer shot



Here's the flare at last being tacked up with the body



I chose to mig weld this one, it was pretty difficult to get a fitup that was good enough for tig. I started at 12 o'clock on the arch, spacing out tacks until I get the whole way around the panel. Then grind the heads of the tacks down so that the next tacks have good penetration, and proceed with another round of welding.



After a couple iterations of welding / grinding, eventually the weld spots overlap each other and you end up with a continuous-ish seam that will then be sealed up with some short strand filler to make it waterproof.

Still a bit of work to do to finish it up but you get the idea.







General look at one finished side with how the car will sit at approximate ride height. Might drop the rear a bit more once I'm able to roll the flare a bit for some additional clearance, but clearance isn't bad as is. I don't run into problems until I'm about 1" away from my bumpstops, but I don't envision ever getting there with 900 lb springs in the rear of the car.



Plenty of room to stuff more tire inboard should I ever want it



As always, thanks for looking. Hoping to get more progress rolling along here in short order.

[Bsaint]

Nice work man!

Those headers are a work of art!

[squashman702]

Lots of work into that flare but it came out great!

[bimerok]

Nice update. Excellent worksmanship!