Hennarot S50B32 M3 consumes my spare time

[Eric]

sliding or correcting?

[Eric]

Of course when you fix one thing, something else breaks...

While at the track mentioned in the post above, I noticed a weird vibration on braking in the 50ish mph range during my second session in the morning. The vibration got worse as the session went on, and after about 5 laps, I pulled in to the pits to investigate (side note, my HF infrared temp gun measured 570°F brake rotors!). After a bit of poking around, I noticed one of the bolts that hold the strut to the control arm/tie rod "dogbone" was loose! These bolts were torqued to spec (28-30ft/lbs) with red loctite, and even a bit of nail polish applied to the bolt heads for quick checks to see if they loosened.

Out came the toolbox, and the 13mm wrench & sockets. I found all four bolts to be some degree of loose, but the bolt most inboard and to the rear sheared off when I applied about 20ft/lb (elbow torque wrench) of force...hmmm, that's not good

In a decision of acceptable risk, I decided that since the 2002 and E28 and the much heavier than my E30 M3, E34/E32/E31 came with a 3 bolt setup from the factory, I could tighten the 3 good bolts and drive a bit less than flat out until I felt the vibration again, which would result in me pitting for the session. Not the most advisable, especially to internet lawyers, but it worked. I'd last an average of 5 laps before the vibration returned and I'd have to pit to remove the wheel and re-tighten the 3 bolts.

Obviously this was not a long term solution! I decided to fix it by being as german as possible... over engineer the shit out of the fix.

So, the fix action would be:
- New 10.9 grade bolts
- bolt threads cleaned with a die
- Tapped hole threads cleaned of old loctite
- Red Loctite
- Torqued to 30ft/lbs
- Safety wired (lock wire)

But of course I don't have any safety wire laying around, and I haven't safety wired a nut since being in A&P school 13 years ago! This can only mean one thing, a trip to harbor freight...

DSC_0192 by ericandshovin, on Flickr


If you'd like to make your own drilled head bolts, I'd recommend buying one of these:


or these:




But if you want to do it the hard way, all you need are these few items
- Drill press vice ($12 HF)
- 1/16th" cobalt drill bit, buy more than one
- Oil to lubricate the drill
- Drill press (handheld would be incredibly difficult)
- good dikes
- good needle nose pliers
- flat head screwdriver
- SAFETY GLASSES



Drilling the hole (pretty self explanatory)
DSC_0198 by ericandshovin, on Flickr



End result. The dogbones take 4 bolts that are 3 different sizes.
DSC_0209 by ericandshovin, on Flickr


Here I did a quick practice run. The keen reader might notice this bolt is different that the ones above. On my last bolt, I broke the 1/16th bit off inside the bolt head. The tip of the bit was literally about to poke through, you could see it bulging! So I had to make a trip to ACE (their nut/bolt selection kills Lowe Depot's) to grab new drill bits (buy Cobalt ones) and I ended picking up all new hardware as I liked it better.
DSC_0201 by ericandshovin, on Flickr



If your interested, I made a little video pretty much explaining everything I just said above, and showing how I safety wired the bolts on the car. My apologies in advance for blocking some of the key moments with my hands accidentally in front of the camera! I'd recommend watching in 720p for the clearest picture.

http://youtu.be/HG9zjAaaUnQ

And here is the final result.
Untitled by ericandshovin, on Flickr

We have our last autocross of the season tomorrow, so hopefully it all holds together!

[Eric]

I've been experiencing fuel starvation on track about 5 seconds after a highly loaded right hand corner (ex: lift, turn-in, on the gas 20ft before the apex). This can happen with as much as 3/4 full rank of gas!

A few weeks ago, I took the fuel pump out of the tank and noticed the rubber reducer/expander was cracked on the large end, see the photo below. This reducer cannot be purchased separately from the dealer, is it a common part in another vehicle I could scavenge? Any ideas on a way to replace it with items sourced locally?


Untitled by ericandshovin, on Flickr



Since I couldn't find a early E30 locally to snatch that rubber piece, I had to improvise a bit...


1st step was to use a special type of teflon tape used on fuel systems & wrap the split part of the reducer to the tube. This took a few tries as there isn't much room around the other pipes, and teflon likes to fold over on itself:





2nd step was to heat shrink the reducer/teflon combo onto the fuel pump:


shrunk






3rd step was raiding the spare parts bin for some small hose clamps and clamping the heat shrink on either end for good measure. Sorry, I forgot to take a photo of this step.


And the result? Two friday's ago I went to a local open lapping day and used an entire tank of fuel with zero starvation! In fact, it wasn't until the light went on that I even had a second thought about it. This is on 235/40/17 Nitto NT01's too, so no shortage of grip to slosh the fuel away from the pickup point.

My guess is that the split in the reducer either allowed air to enter the system when fuel was sloshed to the left side of the tank, or that fuel was pushed out of the split, either way, creating a bit of a gap between the in tank lift pump and the external main pump.

[Eric]

sliding or correcting?

mostly luck!

[2mAn]

sliding or correcting?

[Eric]

Oh my, this won't be good!

Screen Shot 2014-09-12 at 5.24.13 AM by ericandshovin, on Flickr




oh wait, we're all good here.

Screen Shot 2014-09-12 at 5.24.47 AM by ericandshovin, on Flickr

[Eric]

Sent from my iPhone using Tapatalk

[Eric]

A bit of auto-x action from a week or so ago. The car was co-driven this time and the oil temp was creeping up to 260f, with the water temp just under 220f! I think the next major mod will be an electric water pump setup with a PWB to modulate the pump.

[Eric]

Two vids from our local Time Trial back in May. This car is awesome.

[YZ86]

I wish one day my garage will looks like yours. So much win

[Farbin Kaiber]

That pretty part, tell me more!

[Eric]

Untitled by ericandshovin, on Flickr

[Eric]

A bit of auto-x action from yesterday.

[Eric]

Yes, they are BBS made wheels for the Sport EVO. You can still buy them new from the factory, and the nargo center ones are actually cheaper than the normal 16" M3 wheels!

I'm actually packing the car up for an autocross tomorrow! This month has been super busy, this will be the first time I've driven it since the end of June.

[Gus]

Love it! Sorry if mentioned before, but what wheels are they? Sport Evo weaves? Eyeing up 5 stud wheels...