Topic: version 3.0: The MR2 gets a gas turbine engine (Project Outline)
Alright, so with the autobahn race over and the radial engine having been reasonably successful ("butt terrible" according to Jay) it's time for a project evolution. Yes i agree that the radial engine could have been done better and i hope someone else picks up the idea and runs with it, for now I've got to say that the 45miles or so I've driven that thing is enough to have rattled loose the brain cells that thought it was a good idea in the first place.
I'm going to take the radial engine out and I've found someone to trade it for a gas turbine turbo shaft engine. Actually, he found me about 6 months ago wanting to buy my radial
Project Goals: (from highest to lowest importance)
1)Stay married and raise my child properly (this means this project will take more time than last time)
2)Safety: ensure that nobody on the team or any spectator gets injured
3)Reliability: I want it to be possible to drive this thing on the street without worrying about when it will break down
4)Cost: the previous project was relatively cheap, this one should be also (keep in mind, machining time is free for me)
5)Entertainment: I would like this thing to draw crowds just like the radial did. (ok, maybe a few women would be great too)
6)Performance: I have a street car MR2 putting 290hp to the ground and a 13sec 1/4 mile, it feels fantastic and i'd like something similar with this project.
My schedule is going to stay open ended, but this is likely a Lemons 2014 car.
here are a few requirements to this project that simply aren't negotiable:
1)the motor must be mounted in the rear of the car with a short exhaust before it exits the car. no significant bends allowed
2)noise limits. I need to figure out a way to get into the 92dB limit. even if there's any room there, the two nearby tracks (Autobahn and Gingerman) have strict 105dB limits that i definitely cannot exceed.
3)the motor must be mounted longitudinally for exhaust and blade containment reasons. same for any other high speed spiny thingies (flywheels and such)
4)must be able to drive at 10mph pit speed
5)my hearing DEMANDS a vibration isolated drivetrain
now, onto the current discussion point:
The reliability point above does mean that i'll have to concede on the "must be a manual transmission" point of the previous build. this project should get an automatic transmission or a CVT. electronics do not scare me so a CVT seems even more useful than an old school automatic.
i did find the following list of CVTs: http://www.cvt.co.nz/which_cvt_for_what_car.htm the "Audi MultiTronic" seems rather tempting. i found the full information on it here: http://frankensteinmotorworks.com/turbi … tronic.pdf seems that it wants a 4100RPM max input speed, the package includes everything from the input clutch to the differential. overall ratio ranges from 2.12 to 12.72 this means the clutches would have to slip till about 12mph and the turbine would be at full speed at 21mph. from there full power could be applied all the way to 126mph. the trans seems available in for about $1500-2000.
this still leaves the dreaded exactly inverse problem as before: shaft RPMs need to be reduced 3:1 unsure about rotation reversal requirement since i haven't seen the turbine yet.
does anyone have thoughts on transmissions for this beast?