'87 Sports Libre BMW 2cv & 94 MX5 Hillclimbers - MEGA UPDATE

Which brings us to the last event of the season.. and strangely, a non competitive one.. which has always been a no for me, but this one offered half a dozen runs up Shelsley for minimal cash and a weekend hanging out with many friends.

RETRO RIDES!

Me: I'm not trailering to retro rides.
Me: I shall bring all the Liqui Moly promotional stuff and marquee.
Also Me: You're an idiot.

IMG_8737 by Alex de Vries, on Flickr

Camping was fun, met up with the South West Retro Rides (SWRR) gang at Bristol Services and trailed up the motorway with them. Met the Stapley family for bbqing (did you see their guest star DATSUN shared by the daughters?), hillclimbing mad family. Then surprise I saw Jim with his hotrod also as a guest! He made up the beautiful dash in green car and a few other bits and pieces, top craftsman and generally all round interesting chap.

IMG_8794 by Alex de Vries, on Flickr

I have STOLEN all of these pictures from other people so thanks to Joseph Steele, Retro Cars daily, reallyloud.co.uk and the forum moderator for these (who probably don't know I've stolen them...)

Took Bens wife (Stapley family of Datsun fame) up the hill for one run..

IMG_8846 by Alex de Vries, on Flickr

Asked the boss if he wanted a run... too busy running the paddock..

IMG_8848 by Alex de Vries, on Flickr

I never tyre warm/clean at competitive events as it puts too much strain on the first gear lay shaft (chipping teeth), but I couldn't resist for a few occasions.

DSC_7804-1200 by Alex de Vries, on Flickr

IMG_8806 by Alex de Vries, on Flickr

And that was the end of our season, also my 32 birthday and generally fun round up to my summer. Maximum fun.

Joy of Machine.

But... have you noticed the thread title has changed....?

Well now... the Elk and I roadtripped the pacific northwest after I finished my last stint of work in Brazil. We hired a truck and drove from Seattle down to San Fran, covering 2000 miles of no highways. Mountain roads, snow, beaches, sand, rainforest, cities, bar crawls, good food, amazing scenery...... and my ulterior motive...... we stopped at San Jose BMW to build up a set of R1100 racing heads. There has been major work to both the exhaust and inlet ports, we have Del West Titanium valves (2mm larger on the inlet), Titanium retainers, beryllium valve seat, trick cams, lightened valve buckets, stock springs (BMW build bomber gear) and some other fancy bits..

That was going to be it for my motor upgrades for the 2018 season, I was just going to concentrate on some body work restoration, further lightening and handling upgrades. But then I accidentally bought a Rotrex supercharger and its associated oil cooling system. Honest. Massive accident. Was even sober.

The current thinking is:

- Belgium arm upgrade for the front swing arms - bracing the top of the hub to stop the wear on the kingpins by the larger tyres
- Rear arm strengthening - basically a truss to stop the rear arms flexing under the extra sticky tyres
- custom intercooler is already made and fits infront of the motor - this means the oil cooling has to move
- Emerald ECU
- Delphi MAP sensor for the above - otherwise using the stock BMW/Bosch crank & air temp sensors etc
- custom cam sprockets
- Tial Q 50mm blow off valve with supercharger spring
- Aluminium intake plenum custom made from extrusions from Ross Machine Racing
- Stack widebad lambda gauge and sensor
- Spa Designs combined EGT sensor, thermocouples and boost gauge
- sparrow automotive stainless exhaust
- zircotec white ceramic coating for the above - must keep the heat down in the engine bay
- 195/55r15 toyo R88Rs
- uprated clutch
- Setrab Oil coolers x 2, these will be moving to the wings behind the ducts
- carbon kevlar arch protection for oil coolers
- kevlar front and rear arches
- carbon front air dam

The only problem after this is the gearbox. The engine is capable of taking 175/180bhp before the two bearing crank starts to flex. But that gearbox, bearing in mind it was originally designed for 29hp, will probably let go completely at 140/150bhp. It is already eating teeth every now and again when it likes. So whatever happens we'll have to keep power around that sort of level.

The solution to this of course is a sequential box... but that'll cost the same amount that this development is. So that can wait till upgrades after the season... can you imagine flat shifting in green car though? I'm excited already.

With those heads and that supercharger I'd expect to be able to eventually wind it up to just over 150bhp.

Turbo would be the way to 170bhp to 180bhp, a Garret GT2056 specifically with all the upgrades that Turbo Dynamics could do to it. I've already done the calculations and it'd need to be a 56mm, 55 trim, 0.53 A/R. The GT2056 is oil cooled as well so suits my application. For 170hp it would need to push 255cfm, which is 17.870lb/min. With a GT2056 thats a 1.8PR which would be 0.82 bar or 14.psi in normal money. I could run 11psi on the standard pistons which have a compression ratio of 9:1 (FYI 11psi will net 160hp as it would provide 240cfm), a compression ratio of 8:1 would enable 15psi. So not that low as to affect initial acceleration too much, which is my worry hillclimbing.

Pretty much everything should be in place for such an upgrade in the future with just a few changes but I'll give supercharging a go for now, it's always been an interest I've had.

The only problem I foresee from turbo charging is the heat build up, which is already incredible in an oil cooled/air cooled boxer.

That is alot of green awesomeness right there. Love it.

Ok... so I've bought pretty much everything and am just waiting to be home sometime next week to unpack all of the stuff at SSSB. I have had a few thoughts after speaking with Dave Walker at Emerald (what a helpful chap too).

MAPS
Dave mentioned that perhaps I may want some separate maps, they have a nice plug in twirly knob for the ECU that gives you the potential of 3 maps on demand from the cockpit or two maps plus a press button... so my current thoughts are;
- rain/town driving map
- race map
- some sort of start line rev limiter on the mad max button. Ie. hold the button down, floor it and it limits me to, say, 3000rpm on the line, light goes green, dump clutch and finger off button?

BOOST CONTROL??
Who has run some sort of boost controlling with a supercharger?

So I have the TiAL Sport Q 50mm BOV to vent pressure building up against the throttle bodies when they are closed (-2psi spring for supercharged application) so I don't get it thrown back through the Rotrex charger, but what about when I am giving it the beans? I have been thinking about installing a TiAL Sport MVS-A / AR Wastegate just before the inlet plenum, if I had one with the lowest spring pressure possible then I could control it with an VAG boost solenoid and my rain/town driving map could get it to open at certain boost levels to limit my power... right? Worthwhile?

Anything else worth thinking about? Appreciate all sensible input here.

I am very impressed with the green 2CV. In my Acadiane (campervan) I only have a 650cc Visa engine with slightly more torque and power than the original 2cv engine so I'm green with envy seeing the 1100cc monster. That the 2CV gearbox does not really cope with much more is not a supprise. A gearbox of a Citroën Visa 2-cyl is much stronger similar to a GS gerbox but shorter, it is prepared for 2CV o GS brake calipers as well, bu you need to make driveshaft adapters or use rare AMI super driveshafts.

Regarding heat, turbo and CR. If you map the engine for E85 (85% ethanol, 15% gasoline), that may be a solution. E85 is about 104 RON so you can run with much higher CR + boost without detonation. Although E85 has a lower caloric value (per volume) compaired to gasoline but you need ca 35-40% more fuel for the same amount of air so you end upp with more energy/power. The larger amount of fuel to evaporate combined with the greater latent heat of evaporation of ethanol/E85 compared to gasoline results in more than 300% more cooling by the fuel which I think must be an additional benefit once the engine has warmed up?

You can get it, but cheap it isn't..well, not from Tweeks www.demon-tweeks.co.uk/motorsport/race-fuel/sunoco-e85-racing-fuel but maybe speak with FrankenHealey? They had a stand at the Autosport show as well but given the dolly bird and long-shoes-and-crisp-suits staff, gave it a miss as I suspect there weren't many persons of a Technical nature there.

Some BP and Morrisons used to stock a mainstream version apparently but there was a low uptake, tax breaks disappeared, so hence it got dropped.

Will you get this fitted for this season?

Man you have some cool toys. The UMMs and this awesome beastie! What a great machine! Loving reading about the development of it, and all the race reports. Great work!