02-01-2018, 02:40 PM
(02-01-2018, 12:23 PM)Malcolm Parker Wrote: Years ago I ran an Austin 7 special with a belt driven Shorrock C75 supercharger. As tested on Stuart Rolts Dyno, which was accurate, it produced 32.5 bhp at 5000rpm. The car had fabulous torque and most of the time was in top gear, probably aided by the use of 15" wheels. Cooling was a constant problem, even with a water pump fitted. At times there would be ice on the inlet manifold and the exhaust manifold was almost red hot. If it idled too long it would brew up like a volcano.
I removed the blower and still have the engine.
Now I am running an Ulster rep which has a Barlow crank, light pistons, a Pigsty trials cam, standard valves, a Ricardo head (excellent product!) and a 1 1/8" down draft SU. It is running on 19" wheels and is every bit as powerful as the blown car, but much more practical. It has ample torque and romps up serious hills.
If I was new to Austin 7's and I wanted a sporty model I would go for a very simple Ulster replica with an unblown engine similar to that described above. Keep the weight down and fit a gearbox with suitable ratios. Mine is 3 speed with a high second (the Andes box).
An Ulster can be used for almost any type of competition and can be developed into a very potent car as and when time, experience and finances allow.
May we have a cost run down please on rebuilding an engine without using a supercharger, to effectively give more power and torque.
This could be very useful for not just me but other newcomers.
My engine is totally unknown and I certainly don't want to start it up (I haven't even got a complete carb for it yet) and cause damage, so I prefer to strip it down entirely, which will happen in due course.
Could us newcomers be given some expert guidance, re what ought to be replaced as a matter of course, and the overall cost of doing so. The idea being not just a rebuilt engine, but one with additional power. It would appear therefore from your above reply Malcolm that 30 plus BHP can be obtained without a blower being fitted.
Some guidance and costings will be much appreciated. You mention a "Barlow" crank, I don't know of this, I know of Phoenix of course, plus what pistons have you used.
Maybe this kind of guidance could be offered as a standard "document" for newcomers. Maybe, I should make this a new thread....I will.
regards
Arthur