E92 M3 Time Trial build

[Greg S]

This project started off looking for an E92 M3, the only two requirements were that it had a carbon roof and DCT transmission. The intended build of this car was to be a NASA Time Trial 3(TT3) car and eventually after a year or two race it in NASA GTS2-4 or ST2-3, really wherever the best competition is. After a couple months of looking we picked up an Alpine White 2008 M3 with DCT, a carbon roof, and approximately 92k miles. When we purchased the car it has KW V3’s and a Meisterschaft muffler, but part of the deal was that we would remove those and return them to the owner as we had plans to replace those. We ordered most of the parts we would need for the build at once, but we planned to space them out over time.


Before we get into the build, let me fill you in on NASA TT3. TT3 is a weight/HP ratio class with a 9.0 lb/HP limit after correction factors. Cars receive positive and negative correction factors depending on what tires they run, how much they weigh, what transmission they have, if they have ‘aero’ and other factors. The short rules are available here. The goal of this car is to reset all the TT3 lap records in Texas held by a certain red Mustang and win TT3 at NASA East coast nationals at Watkins Glen in 2016. TT is done on a best lap per day basis, so a 2 day event can have a different winner per day, per class.

We got a baseline dyno of 310WHP and 240 TRQ, which is lower than low on these motors in my opinion. I was able to get my hands on a customer’s E92 M3 DCT about a week later which he let us dyno, his car made 336WHP and 250 TRQ on the same dyno. This dyno is comparing the two cars, both stock.


A compression and leakdown test was done on our car and revealed nothing out of the ordinary for a 92k mile motor, the worst leakdown was 6% and the compression range was within 10psi. We installed new spark plugs, pre-cat O2 sensors, a new air filter and dynoed again and it made 308WHP, within the range of dyno accuracy from day to day in my experience

After chasing the lost power we thought maybe the knock sensors were picking up noise from worn rod bearings, so the first round of real work done to the car was to replace the rod bearings and bolts which was something we were planning on doing anyways. We chose to go with the BimmerWorld WPC treated rod bearing and ARP rod bolts as we’ve been using their kits on S54’s for years and a few S65’s with good results.

As you can see, the number 4 rod bearing was in very bad shape, it’s also worth noting that the number 4 bearing is the rear most rod on the crankshaft. The number 6 rod bearing was showing a little copper as well. The crank surface was checked for scoring and deposits which there was none. First up a dry assembly with Plastigauge to make sure nothing is out of spec, all showed inbetween .0015” and .002”. Next up is final assembly with assembly lube with ARP rod bolts torqued to spec. New o-rings are used on the oil pump pickup tubes, a new oil pan gasket, and new BimmerWorld performance motor mounts which are similar to the Group N mounts, but far cheaper.

We dynoed again after the rod bearings and the car made 314WHP and 240TRQ, no significant change. Graph shows initial dyno vs post rod bearing replacement.


We gave it one last shot by replacing all the coils since the coils are used to monitor knocking, misfires, and poor combustion, and seeing how jagged the dyno graph was up top we thought they might’ve been the culprit. The car made 311WHP and 236TRQ after changing all the coils, within day to day dyno variance in my opinion. At this point we thought of possibly selling the car and picking up another (of course we would dyno before purchasing this time!), but we eventually decided to keep it and persevere. We had plans for power adders anyways, originally we were shooting for 410WHP, but those goals had been dashed.

Next up: Suspension and braking

[Greg S]

Parts had been accumulating on the shelf and I was going to be instructing at a BMW Club Racing School in a few weeks and I wanted to put some of the parts we had been accumulating to good use. We also removed the KW V3s and Meisterschaft exhaust and returned them to the previous owner.

Braking:
Performance Friction Z54 custom painted lime green
PFC 11 pads all around
BimmerWorld SS rear brake lines
BimmerWorld brass guides for rear calipers

Suspension:
Motion Control Suspension double adjustable remote reservoir dampers(true coilover rear)
Ground Control race camber plates
Hyperco springs
Torrington bearings
BimmerWorld front swaybar endlinks
BimmerWorld front race arm conversion
BimmerWorld rear toe arm
BimmerWorld rear upper camber arm
BimmerWorld rear guiding link
BimmerWorld rear trailing link bearings
BimmerWorld rear lower camber arm bearings
BimmerWorld aluminum subframe mounts
BimmerWorld aluminum differential mounts
BimmerWorld 90mm premium wheel studs




With everything apart now was a good time to put everything in the ultrasonic parts cleaner and replace the wheel bearings front and rear. BimmerWorld brass caliper guides, BimmerWorld SS brake lines, PFC 11 pads, and ultrasonic cleaning for the rear calipers. The ultrasonic cleaner has been one my favorite purchases recently.


The rear suspension coming together:


Front suspension and brakes coming together, note the massive pad volume of the PFC calipers:


We also had some 18”x10.5” ARC8’s sitting on the shelf waiting for this car, we temporarily mounted some old scrub Hankooks on them. Awaiting an alignment and corner balance:


275/35/18 Bridgestone RE-71R’s were ordered and installed and the car was corner balanced and aligned. At this point the car weighed 3750lbs with driver, low on fuel. I weigh about 205lbs. The car ran well at the BMW Club Race School at Texas World Speedway, all I did was add fuel and check tire pressures. Water and oil temps were high as I had suspected, I would have to back off of it for a lap occasionally to let it cool down, I don’t think that will come as a surprise to many people. My fastest lap was a 1:55.83, not bad for street tires in 90* weather.


Next up: real tires and power!

[Greg S]

The BMW Club Race School was really a shake down, the balance of the car was good and the diff did better than I expected as I hated them in the E46 M3. I wasn’t too worried about the heat issue as this is a time trial car for now generally running for a warm up lap, 2 hot laps, and a cool down lap.

295/30/18 Hoosier A7’s were ordered and installed which required some playing with the alignment, springs, and control arm lengths. The front tender springs were removed and we switched to a 5” front spring to get the front height collar higher, rear control arm length was altered for tire clearance in the rear, and we also went more aggressive with the alignment specs. A 5mm spacer was also needed in the front to get the tire off the front spring perch, no spacers were used in the rear.

With the wheels/tires, suspension, and brakes mostly figured out it was time to make some more power. I had the BimmerWorld Tri-Y headers and X-pipe sitting on the shelf among some other goodies ready for install. For the rear section I went custom with twin 2.5” burns mufflers to save weight and it will also play into future plans for the car.


Header install requires dropping the front subframe but not complete removal. Of course new header gaskets are used, surprisingly the left and right side have different part numbers, but they can really be used interchangeably.

Since the BimmerWorld headers are a thicker wall and longer they’re heavier than stock at 10.3lbs per side, versus 4.7lbs for stock.


The BimmerWorld X-pipe midsection weighs in at 22.7lbs versus 36.7 lbs for the stock midsection.


Since I’ll be going custom for the rear section I can’t give a direct comparison of what mine weighs relative to stock, but the stock coupe muffler weighs in at 53.3 lbs. My setup will be dual 2.5” Burns Stainless mufflers dumping the exhaust right behind the axle with turn downs, these mufflers are extremely light at 3.1lbs a piece.


For initial assembly I bolted it up to the stock exhaust. If you look closely you can see how it tapers from 3.0 down to 2.5”.


The custom rear section required cutting a little over a foot off of the BimmerWorld midsection in order to get the Burns mufflers tucked up in the larger cavity near the fuel tank. The heat shielding remains and an additional layer of heat reflective film was applied directly the fuel tank. Dual V band clamps were also added just upstream of the mufflers for easy removal, and finally turns downs were welded onto the end. The final weight of the entire midsection with the mufflers was 35.9lbs. The total weight saving was 42.9 lbs from the motor back(99.4lbs vs 56.5lbs).


A Macht Schnell stage 2 intake and their underdrive pullies were installed, no pictures of these because we’ve all seen them. The final power adder was a tune from EPIC motorsports. This dyno shows 3 runs from the most recent previous dyno, versus 3 runs after I/H/E, pullies and tune on the same dyno. This is a gain of 55 peak HP, and 60HP in some places on the graph, and 29 lb ft peak torque and 47 lb ft in some places. AFR’s were also greatly improved.


There were some concerns of the dyno accuracy of the dyno I had been using for all the previous runs so I put it on a different dyno where it made 10 more WHP and 7 more lb ft of torque, for 376 WHP and 272 TRQ. This higher dyno is what I’ll be using for my NASA dyno form.


Next up: NASA TT3 competition

[1MOREMOD]

Well positive is with that low of power you can go bonkers on weight reduction, aero, and tires and still be within tt3. Have same power in my e46 m3. Little harder to get yours sub 3000lbs though

[AriuSen]

damn nice suspension parts!!! all bimmerworld
and so shocked how bad the rod bearings are!!

[warp10]

this is great. what are you impressions of the bimmerworld pieces? they are next on my build list

[ThunderMoose]

Originally Posted by 1MOREMOD

Well positive is with that low of power you can go bonkers on weight reduction, aero, and tires and still be within tt3. Have same power in my e46 m3. Little harder to get yours sub 3000lbs though

You're making 376 whp? What power mods and tune?

[1MOREMOD]

Originally Posted by ThunderMoose

You're making 376 whp? What power mods and tune?

I wish, missed that saw the initial 300 dyno

[Adrian g.]

Nice build Greg.

[PrimeBMW]

Keep up the good work. It looks like you are doing everything right! Post up a video/sound clip. I would like to hear the sound of the car with the Burns mufflers. (I have a set for my build but have yet to hear them )

[Greg S]

Originally Posted by PrimeBMW

Keep up the good work. It looks like you are doing everything right! Post up a video/sound clip. I would like to hear the sound of the car with the Burns mufflers. (I have a set for my build but have yet to hear them )

I think they sound fantastic and have received many compliments, it sounds amazing downshifting with the DCT.

Click image for video:

[jakob66]

Greg
Nice work and really smart job with the exhaust! Cutting 42.9 lbs from behind the rear axle is the way to go. That thing will turn! What battery do you have?

I'm in progress installing the front BW arm conversion myself but have some issues with the larger drop of my KW CS (vs. your MCS) and ergo with the lower control arm rode end on the wheel side. As of now I can only install once I compress the shocks.

Keep up the good work!

[Jonathan@BimmerWorld]

Nicely detailed write up, and looking forward to updates on this. Car is going to be very quick!

[SYT_Shadow]

A reason for the really low initial dyno is the old software. If you update to oem software you get 20hp more.
Apparently you should update to the latest software before getting a tune.

[///Mobbin]

Awesome build, thanks for sharing!

I'm curious if you ever go out with Driver's Edge? I'll be at TWS in less than two weeks with them.

[AriuSen]

do you mind sharing your thoughts on bimmerworld suspension parts?

[lutfy]

Originally Posted by Greg S

I think they sound fantastic and have received many compliments, it sounds amazing downshifting with the DCT.

Click image for video:

Good work Greg! Car sounds awesome! Sold the E46 JP? Saw Thomas/Garrity LTW in your pic is he tracking that car now?

Build related question: why did you go all out on power initially rather than stripping the car down and baselining. For instance headers would be the last thing to install no?

Subscribed and very excited about this build.

Lutfy

[M3 Number 86]

that brake kit though......

[SYT_Shadow]

Originally Posted by M3 Number 86

that brake kit though......

I have the same one. It is incredible, it has the most massive pads you can imagine

Definitely the way to go for a serious track car

[M3 Number 86]

Originally Posted by SYT_Shadow

I have the same one. It is incredible, it has the most massive pads you can imagine

Definitely the way to go for a serious track car

yeah looks serious!

[SYT_Shadow]

Originally Posted by M3 Number 86

yeah looks serious!

Check those pads out vs OEM

The chamfer and center 'hole' are there because these are the bbk street pads. The track compounds are just massively square

[nicksm3]

This is such a great write up! I actually responded to you on FB about the 10.5 square setup. I would love to hear the exhaust setup. Are are the BW suspension components..I may opt for them