Riddleyo's Autocross 318ti

[riddleyo]

Riddleyo's Autocross 318ti

The Car:
1997 BMW 318ti BLACK

The Goals:
Ultra Grip!
Autocross!

The Background:
I race with a club in Xenia, Ohio called the Miami Valley Sports Car Club. I will be racing this BMW starting in the 2016 season. If you are interested in coming to see the car, go to our website and show up to an event or two. This BMW is my 4th autocross project and have had countless Toyota projects in the past. This is my first foray into BMW - but I have no fear because I remembered to bring my wallet. I will document the work I do to the car and I welcome my competitors here, no secrets to hide!

The Story:

Picked this car up in early 2016 to replace my previous autocross car. Here it is the day I towed it home. I needed a change from the underpowered Toyotas of my past and I'm ready for some German muscle:


The Good:
The car came with plenty of goodies including a Downing Atlanta Supercharger and polyurethane bushings throughout. M-sport aerodynamic exterior bits and good looking paint.

The Bad:
Disconnected sunroof drains had to be fixed. It also needs a suspension refresh as the rear suspension bushings are toast. Perfect starting platform for an autocross car!

The Build:
The first thing that needs to be done is to fix the suspension. Without further ado, it begins:


Subframe has been dropped. No pics, I was too busy cursing and wrestling with the weight of the assembly. Top it off with bent and corroded subframe bolts which made removal very difficult.



Some shots of the undercarriage post subframe-ectomy:



Bare rusty salty subframe:

[riddleyo]

The previous owner installed Ireland Engineering eccentric camber/toe bolts. They were rusted to hell and combined with shot rear trailing arm bushings, the whole crap setup had to go. Had to use a cut off wheel to fight through the corrosion and this is what is left:


After some wire wheeling, the subframe starts to clean up:


I am pretty anal about the little details and dirty nuts and bolts drive me crazy. This is how they look at first:


I've had fantastic results with EvapoRust. It is commonly found at Autozone, NAPA, wherever. It is a non-toxic chelating agent that eats through rust like no other. It is NOT an acid or an etcher, so it works well to remove rust but does not fully prepare for paint.


The result is striking. Clean metal, almost looks like new hardware and I put NO effort into this. I simply dumped these into a plastic container with EvapoRust and pulled them out the next morning. NO WIRE WHEEL NEEDED!!! (I'm don't sell EvapoRust, I just love the results)


Another product I use to combat rust is phosphoric acid. The brand is Klean-Strip and I found this product at Home Depot. This acid etches the metal and dissolves rust in a very caustic manner.


The reason I use etcher is to prepare the metal for paint. Here is some hardware before:


Afterwards the rust is dissolved and a white flaky acid powder residue remains:


After prep, I start painting with POR-15. A great paint that is brushed on and prevents rust from returning. Very durable and low odor.



Here is some of the hardware drying.

[riddleyo]

Now I turn attention to the trailing arms.


After burning out the old worn bushings, I flap wheel the inside surface with a dremel.


Wire wheel the surface of the trailing arm to prep for paint:


And then acid etch with phosphoric acid:


I also etched parts of the undercarriage:



After some POR-15 on the trailing arms, they turn out fantastic. The surface is very durable. I can strike with a hammer and it bounces off the POR with no damage.


Subframe looks great as well:


Now it is time to work on the Subframe's trailing arm boxes. I ordered Ireland Engineering's "Positive Lock" Camber and Toe adjusters. Honestly I am not too impressed with Ireland Engineering's customer service. These were on backorder for a long time. However, these are well made pieces but are very costly. Here is what your receive:


Now I level the subframe:


And I start the mockup process:


Now I use cardboard engineering and make templates that will reinforce the camber and toe plates:



Transfer the templates to good old American Steel!


I use white out and lay out where I need to grind in preparation for welding:

[riddleyo]

It was a sunny day today and I got a lot done. First, used a grinder to prepare the subframe for welding:


Bare metal is good:


All the cardboard templates have been transferred to steel and cut out and labeled:


Now to mock up the toe and camber plates again, being sure to keep everything level and square:


After a little bending and grinding, the steel reinforcements are complete. These will be essential to keeping the toe and camber plates from shifting under the high loads the car will experience during cornering with race slicks.



Welding will take place another day. To finish up today, I painted some more of the undercarriage with POR-15 after etching with phosphoric acid. This car will have no rust by the time I am done with it - and will stay rust free for years to come.

[BlackBMWs]

Thanks for posting this. I am looking forward to following this thread. Cheers!

[stevenwrichards]

Must follow. Finishing up my Ti in Ann Arbor, plenty of extras if you need anything.


Sent from my iPad using Tapatalk

[anassa]

Originally Posted by riddleyo

I needed a change from the underpowered Toyotas of my past and I'm ready for some German muscle:

Wants German muscle --> buys a 318ti.

Oh the irony! If this wasn't 318ti.org people would of had fun with that part!

That being said, it looks like a good project, you also seem to be well prepared!

Good luck.

[BlackBMWs]

I'm interested in more detail about the reinforcement tabs you made for the subframe if that is possible. I have a spare subframe I can prepare as well.


Sent from my iPhone using Tapatalk

[riddleyo]

Originally Posted by anassa

Wants German muscle --> buys a 318ti.

Oh the irony! If this wasn't 318ti.org people would of had fun with that part!

But.. but... it's supercharged! Maybe when I get tired of battling the miatas, I'll put in the straight 6.

Originally Posted by stevenwrichards

Must follow. Finishing up my Ti in Ann Arbor, plenty of extras if you need anything.

I'll keep ya in mind, thank you.

Originally Posted by BlackBMWs

I'm interested in more detail about the reinforcement tabs you made for the subframe if that is possible. I have a spare subframe I can prepare as well.

I just made them up as I went. I put two tabs on the side of each toe plates and camber plates. For the camber plates, I put a plate in the middle to reinforce it further. Welded them up just like pictured in the previous post. Welds aren't the prettiest, but they are strong as hell. The plates were oriented to reinforce the tabs against lateral loads which will be encountered in autocross. Here is how it looked shortly after welding the tabs in:


Here is a closeup of the passenger side toe adjustment plates (pictured right), and camber adjustment plates (pictured left):


Now here are the driver sides:


Another view, this time on the other side of the driver side adjustments:


The two camber adjustments, driver side on right, passenger side on left:


And the whole subframe, welding is complete:


Next, I prepped and painted the subframe with POR-15. I avoided the serrated surface so that the thickness of the paint does not physically interfere with the serated interfaces:






Now, this weekend, I hope to make some progress on installation. In the meantime, the paint is curing.

[anassa]

Originally Posted by riddleyo

But.. but... it's supercharged! Maybe when I get tired of battling the miatas, I'll put in the straight 6.

The DASC will definitely give it some umph! Also it can also be made to have decent power while keeping the front relatively light. Something else you might want to consider and will make a noticeable difference is a z3 steering rack! Those tight corners will be a lot easier to navigate.

Keep it up!

[riddleyo]

Delrin trailing arm bushings from Ireland engineering getting greased:


Using a 6" C-clamp to press in the bushing pin into the trailing arm:


First trailing arm installed:


Both installed. On the right you can see my brand new race rubber: BF Goodrich RE-1s


Using a brake line bender to bend new brake lines to match the OEM shape. I believe they ended up being 30" total for both the rear lines. By the way, I had to undo this bend after I took the picture because I forgot.. you MUST have the fitting located at the end of the line before you put the first bend in!


Plenty of anti-seize on the subframe bolts to prevent future corrosion. This is over top of a POR-15 coating which will prevent ANY future corrosion from occurring.


My dad came over on Father's Day to help me install the subframe. We devised a ramp using wood planks and two jacks. Worked like a charm but wow, was it heavy. Wrestling the differential in was a trip as well. Great way to spend Father's day though.


Going up


Raising into place


AND IT'S IN!


Ireland Engineering's rear coil adjusters. They aren't as high quality as ground control sleeves and they use a basic "grub screw" which eats up the threads as you tighten it. However, it does the trick and allows me to fine tune the rear ride height. It also utilizes tiny 2.25"x5" coil springs which can be had at almost any spring rate imaginable... and cheap! I got some Eibach 0500.225.0500 springs which gives me a spring rate of 500 lbs/in. Pretty stiff for autocross, should work well for some on demand power on oversteer. There is nothing like steering with the throttle and you just have to experience it to know what I'm talking about!


All up


Took some time to polish my exhaust with some steel wool and metal polish:


Polished Strömung Stainless Steel exhaust tip:


So at this point, the car is complete, just in time for this weekend's race, and loaded up on my trailer. The Ireland rear camber adjusters were a breeze to set up a guesstimate alignment. The rear coil adjusters made it so simple to adjust the rear ride height and I don't even have to take off a wheel to adjust the ride height!!! So simple.




These RE-1s are road racing compound but were cheap enough to use as break in tires for the season. The car's first race is this Sunday and I barely got it all together in time. We will be racing at Wilmington OH at the airport on June 26th, 2016, if any locals want to come out and watch. Till then!

[riddleyo]

After a great season, I think it is time for me to move on to the next autocross project for next year. I need to move up a class and this beautiful BMW is now for sale. Pretty much all the problems are fixed with the car, it will make a good looking daily driver for someone.

http://www.318ti.org/forum/showthread.php?t=42803

[BlackBMWs]

Posted up on FB for a few friends who may be interested... GLWTS Nice job overall.

[BMW_Hatchback]

Loved reading through your subframe refresh. Thank you for sharing and GLWS

[b0m]

Internet people don't understand the love: http://jalopnik.com/for-6-499-could-...and-1787874730

GLWS!