the type 4 in Northampton was junk too and not at all as described - I think the picture was taken about 10yr ago
I looked around at more type 4's, started playing out options and things. I just couldn't get my head around the look of a standard type-4, and the cost seemed to be 3-4x higher for everything. When you start adding the CSP upright fan conversion, etc., (which having seen it in person, looks great by the way! ) it gets pretty expensive..
I'm not 100% sure I will need it at the BHP levels I'm shooting for either, and so I kind of decided to go the more tried-and-tested route of a Type 1 engine for the build.. ..should amie want some screaming twin-plugged 2.7 911 engine further down the line she can fund it
In all seriousness though, I started thinking about BHP / Ton figures, and comparing to cars we own/have owned, and I think 125-ish BHP & LBFT will be a great starting point for this car. If I manage to squeeze another 10-15bhp from it then great
I ended up buying a solid t1 case from a forum member (actually via ebay, but small world) and will base the engine around that
I'm looking at a low-ish effort build (ie machined-in barrels but no massive stroker cranks requiring ridiculous CNC clearance work). I keep looking at options and started at 1904cc (90.5mm barrels x 74mm stroke) for a solid build - thick barrel walls, etc. however I've discovered thick-wall 92's and think that is the way to go, as you retain the decent wall thickness of the 90.5mm barrels but gain a little capacity..
I know you can get away with 74mm stroke without any case-clearancing work, which gets me to 1968cc with a 92mm thick wall
I think I can also go to a 76mm crank with I or H beam rods and no clearancing, which yields 2020cc
I guess the question is, is it worth doing some light clearancing (and the rods) to get to 2073cc (92 thick wall barrels x 78mm stroke)
..bearing in mind I will be doing the work (clearancing, not case machining) myself I'm not sure it matters either way, so around 2.0 - 2.1 litre capacity is the target. Right now I'm thinking 2020cc for an easy life and a bolt-together (ish) build
Re: fueling - I dug into the spares box for my spare MS2, and surprised to find there are two in there
one now up for saleThe other looks fairly well suited as is for this engine, however will get a little re-configuring at some point.. I will run EDIS-4 I think rather than coil-on-plug as originally planned - it has "limp-home" built in and the marginal benefit from COP on an engine like this doesn't really outweigh that peace of mind factor
Currently eyeing up VFR800 throttle bodies, which look like they will pretty much drop-onto DRLA manifolds, requiring only some work to make new brackets, vac lines, fuel lines etc which is all simple
Based on my sums:
The size of the barrels are good for about 240bhp on two airboxes (assuming no restrictions) so plenty of head-room
The injectors are good for about 175bhp @ 3bar and 85% duty cycle - plenty for this engine which is great!
At idle they should be spot on too.. Think this will be a nice solution, and they're pretty flat too so should fit (height wise) no issues.. The only sad thing is they have a BRILLIANT method of cold start/choke which I can't really use - there's a small wax capsule which sits inside a T-shape which has coolant flowing across the bottom of it (across the top of the T) and out the bottom of the T there is a cable.. This pulls open one small throttle bypass when cold, and lets it close under spring tension when warm! very neat and economical (as always with motorbikes) but no real way of using it as-is on an air cooled engine
Maybe I will look into some kind of air-version of it
