New Exhaust Header and Wrap for R53 MINI

Toward the end of my last track session for 2018 I noticed a significant change in exhaust tone. I thought the larger second position OEM cat had finally failed, but it turns out it was the first smaller cat ahead of it. If you see a break like this, you should also check your motor mounts. Chances are one or more of your mounts is broken or weak, causing excessive movement of the engine. This additional rocking of the engine finds the weakest point in the exhaust and causes either the flex joint or this joint to fail.

This turns out to also be the most common cause of emissions test failures for this car. The joint fails causing a leak and then the second O2 sensor throws a code. If you’re looking at a used car to buy, check out the area circled in red below:

It can be repaired, but if you’re going to go to the trouble to pull off the manifold to weld it, you might want to consider buying a new one so you don’t have to repair it again in a couple of years when something else breaks. The stock part number is 18407566102 and it costs about $1100 to replace with OEM parts. Alternatively, you could go with an aftermarket OE style manifold which costs about half.

A third possibility is to go with a performance header and supply your own cat if you want to keep it road legal. That’s the route we’re trying. We got a Megan Racing Header along with a MagnaFlow 49-state catalytic converter and had it fabricated to match the cat-delete pipe.


MINI placed the electric power steering pump and steering rack very close to the header. If the pump ever over-heats it turns itself off. If this happens on the track (which it has to me) it can be very unsettling as the steering instantly becomes VERY heavy. So before installing the header, I decided to wrap it with DEI header wrap. This video shows how to do it.

MINI R53 Lower Engine Mount Replacement DIY

Your MINI motor mounts will fail. It’s a matter of “when” not “if.” The stock rubber bushings age and harden over time especially if you track your car. The stock bushings were designed to reduce vibration not for performance.

We already replaced the top motor mount on this car, but ended up sticking with the stock mount since we were still daily driving the car at the time and the racing mount was just too harsh for the daily commute. Now that this is a dedicated track car, we’re going to replace the bushings with racing mounts as they wear out.  The first one to go is the lower mount.

When it comes to replacing the stock mount you have a couple of options. You could just go with OEM which runs about $140 for the mount. Go aftermarket for $40-$60. And then just add a polyurethane insert for about $33. We decided to try the semi-solid mount from Torque Solution. Made of billet aluminum and 70 Durometer polyurethane. It should significantly reduce engine movement without transmitting too much engine vibration to the chassis. Installation is very simple and should take less than 30 minutes.

Safely jack the front of your car high enough that you can get a wrench on the mounting bolts. You don’t necessarily have to jack the engine, but we wanted to make sure there wasn’t any pressure on the mount when we unbolted the bracket from the engine.

First remove the center bolt of the large bushing with a 16mm socket, and then remove the other 16 mm bolt that runs through the bracket on the small end. Remove the four 13 mm bolts that hold the bracket to the oil pan.

Installation is the reverse of removal. Tighten the four 13 mm bolts to the oil pan and torque to 28 lb-ft. Hand tighten the two 16 mm bolts and lower the engine if you jacked it for removal before torquing to 78 lb-ft. 

(not so) paintless dent repair

A few years ago, a strong wind blew the telephone line off of our house and into the MINI. Parked six inches to the right it would have missed.  Six inches to the left and it would have broken the rear window. I suppose I should have been happy it just dented the fender. The dent was in a place that made it a poor candidate for pointless dent repair, but that didn’t stop me from trying. Ultimately I fell back on the wiz – scratch wizard that is. Here’s the journey:

The dent wasn’t huge, but I noticed it each time I opened the hatch. The hook didn’t crack the paint, but it did crack the clear-coat, which will become an issue shortly.

I started by buying a cheap set of PDR tools on Amazon.  First tool to try is the external dent puller. This tool pulls the dent from the surface using small glue tips that pull and release.  

After several pulls, you can start to see the dent getting smaller. That is, until it just pulls off the clear-coat that was damaged by the falling hook. I was getting the dent to move, but crossed the line  into “not-so-paintless” dent repair. I chipped away additional failing clear-coat and pulled a few more times.

I was making progress, but since I was now pulling on the base coat, I thought it best to shift to the inside and try pushing with other PDR tools in the bag.

I made pretty good progress pushing from the inside and hammering from the outside. I probably would have kept up with this approach if the clear-coat wasn’t missing.  Another hour and it would be almost undetectable, but since I was going to have to use some filler to try to level the clear, I just switched over to the Scratch Wizard body filler. 

After a little bit of filler…

and a little bit of primer…

It was ready for paint.

And clear-coat.  All together, there were 5 coats of primer; 4 coats of paint; and 3 coats  of clear-coat that I tried to feather into the rear quarter panel.  I need to level the paint after it hardens a bit and then seal. Total repair cost: $125. I’m pretty happy with it. Now on to the hatch lid where the clear-coat is failing in large chunks.

I’ve been thinking about covering the hatch lid in vinyl then removing it. If it works like the test area above, it will come off in sheets.

GeorgeCo Garage Tests: Bead Maker

Automotive protective coatings have come a long way since your father’s can of Simoniz. (Which for the record is actually a different word than “Simonize” which is a recognized synonym  for the transitive verb “to polish.” Who knew….)

There is an amazing variety of coating and sealants available today with prices ranging from tens to thousands of dollars. A professionally applied ceramic coating is a thing of wonder. But what about the DIYer? I’m going to stay away from the DIY ceramic coating for the moment (too many horror stories about water spots), and take a look at a couple of popular polymer coatings which promise 3-6 months of protection, starting with P&S Bead Maker.

MINI revisits the Dyno

It’s been over seven years since I had John Behe tune the MINI, so I took it back to the Dyno at RPR Performance to see how it’s doing. This car has just bolt-on mods: 15% SC reduction pulley, JCW injectors, cold air intake, and exhaust. We’re currently running MSD wires and coil pack, with Brisk Racing Plugs that are one-step cooler than stock. The intercooler diverter has been modified to try to improve charge cooling. And that’s it.

I’ve had the car dyno’d a few times. When I purchased it in 2011 when it was still stock with 48k miles. After the tune I got when the SC reduction pulley was installed a few months later at about 55k miles, and then in October 2018 just to see how it was holding up now that I’m approaching 100k miles.

The data is interesting for a couple of reasons. There is a drop in HP above 6000 RPM and it starts to run rich until about 6600 RPM then seems to come back to the expected values.  Don’t know if there was something funky with this pull, or if perhaps there’s an air leak on high boost.

I plotted the data against previous runs. I had to extrapolate some values since I only had data on 250 RPM intervals, but it’s generally good.  The comparison is stock; MTH tune (on my prior MINI); the original tune on this car; and then today. Overall it’s holding up pretty well.

I like to use the MTH comparison for people who are thinking about a canned tune.  MTH isn’t around any more, but this was an inexpensive tune you could get over the internet.  You just told the tuner the mods you had and they sent you back a tune.  Pretty good bank for the buck, but you see the real gains in a custom tune when you look at low end torque.

It’s a little hard to read in the chart, but the orange lines are the most recent dyno results (solid line is HP; dashed line is torque). Yellow is the custom tune. Green is stock and blue is MTH.

During the off-season I’ll go over the engine and look for the leak. (I can hear it at high RPM.) It’s not throwing any codes so it’s either ahead of the MAP sensor, or after the Cat (or both). It’s about time to replace vacuum hoses anyway.