I'm in the process of building a max power for the street 1500 in my
Midget (same as the Spit).
I have done lots of reading and worked closely with people at Triumph Tune in
UK who have done lots with these engines. One disapointing thing is that
you will never be able to get as much power from this motor as you will the
A series engine. The peole as Ocelli and TT have tried but the 1500
gets very hot at local points insdie and self destructs. Oil coolers, syn
oil, or big radiators don't help in this case. But you can produce a fast,
powerful road engine without these problems as long as don't over do it.
The rules are: work the head for best flow and make the lower half
bullet proof. You don't want a fast engine which is not reliable or which
does not have a useful life. Next thing, it will take $$. Although I've
looked very hard, I can't find a cheap way round it.
I have: a stage 3 head, polished and ported with std size valves. 3 angle
valve job, stainles steel stellite tipped flowed valves. A CR of 9.5:1.
I will use an SK carb, roller rockers, and a bunch of lightened components
such as cam followers, push rods, spring retainers etc. TT suggested their
Sprint 90 cam for use with the roller rockers, this type of head, carb, and
CR. I stressed that I wanted a street drivable motor. If it is set up
well, ie blueprint, balance etc the lower half it should not be too
tempramental low down in the rev band.
The Sprint 90 cam has a very long duration, so I'm alittle worried about
low power low down in the rev band but they assured me that it would be OK.
I also have a vernier adjustable duplex timmimg set-up. I will use the std
TR6 forged pistons (when I get the $$).
I can't yet decide about the distributor.
You can always get a ready made motor from Paeco for about $2000 which actually
works out at a decent price. They list the hp for this type of motor and
its about 90 or abit more, maybe 98.
etc etc etc.
I also have a 1296 I'm fooling around with.
Cheers Dennis
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