Hi Guys, yes, I will be doing this myself - time permitting -
The blower is from a volkswagon specialist, I was ringing around trying to get a g-lader compressor when I found a guy with the Rotrex, he had it on a 20v vw unit giving about 275 @ flywheel. Unit is 3 weeks use only - he changed to a giant turbo lol..
For £500 I managed to get the blower - which is tiny.. , the oil cooler (although it can be lubricated from the power steering circuit) and a couple of pipe lengths.
heres the plan so far..
where to mount it..
on a 172 there is hardly any spare sace at the alternator end of the unit, I would also require my A/C to be retained. the mounting at the mo in the 172 for anilliaries is - bottom to top - a/c unit, power steering pump then alternator.
I am hoping to move the power steering pump - either by using an electric pump from the cup series (bulkhead mount) or by driving the pump from the rear of the alternator (as per some vauxhall).
the alternator can be moved down, and then the blower mounted where the alternator sits now - similar size too.
one belt will be used to drive a/c, alternator and blower.
the front ali housing for the ancilliaries may need replacing with a custom unit
.. that will be fun..
I am looking for about 7-9 psi boost, this should give about 250 at the flywheel.
a water to air heat exchanger (homemade) will cool the charge. Electric pump for the coolant to a front mounted rad - can be a lot smaller than an air to air intercooler too.
as for ecu mods etc.hmmmmmmmmmmm
well, the biggest problem with the 172 mk2 is that the fuel rail is a returnless system, the pump and regulator is in the tank. some of the bosch units (not sure what reno use yet) are electricaly adjustabe for pressure.. so thats a possibility, otherwise a seperate fuel pump and reg may have to be used..
alternatives are bigger injectors but will have to see how the ecu handles that.
as for map sensor etc, it may well be possible to apply pressurised air to the atmospheric port on the MAP sensor so it never sees boost, I am working on that now LOL...
no ignition mods planned at this stage as the boost will be relatively low.
money has not exhacnaged hands yet as I am awaiting confirmation of the exact model number - all flow maps are available on the rotrex site.
out of interest, I have also been offered a sprintex unit.. this is much bigger, but may actually mount more easily along the front of the engine
I am looking into this at the mo..
heres some shots of the sprintex unit.. the carbs and manifold are replaced with an elbow, the outlet is also changed to an elbow.
this unit, although larger, may well be able to use the existing power steering pump drive housing with the blower along the front of the engine, the electric fan would need moving though..
http://homepage.ntlworld.com/captainslarty/sprintex%201.jpg
http://homepage.ntlworld.com/captainslarty/sprintex%202.jpg
Joe.