Hi Rob,
The first question is, were the AAS needles fitted as the result of a
rolling
road tuning session or are they a guess. Secondly which cam have you fitted,
some of the fast road profiles for this engine are meant to work in the range
you've described.
My own 1500 Midget has a free-flow exhaust system (including manifold)
fitted,
carb throttle disks without the emission valves ( the older plain type ), a
fast
road cam (Triumph Tune Fast Road 83), a K+N air filter with AAT needles and a
home brew cylinder head with 1300 size valves (bigger inlets). Untill the valve
sizes were changed the engine had more power throughout the rev range and would
run well upto a 6000 rpm limit, but power was best from 2500-5000. The car has
never been set up properly (it will be someday), but a quick check on a rolling
road suggested power as 80 bhp at the wheels.
The larger inlet valves have helped the power above 3000 rpm but power
at low
revs is slightly down, although the car is still fun to drive anywhere. Indeed
it felt (very subjective I'm afraid) almost as quick as my V8.
As to whether it should run to the 6000 rpm limit, I would say don't do
it
very often! The engine has a long stroke length and while people have raced
these engines with 7000 rpm or higher limits they have decided to afford
regular rebuilds. The conrods appear to be a bit weak, especially their bolts
which should always be replaced if you have the bottom of the engine apart.
If you want more speed or lower revs at motorway speeds fit a Spitfire
overdrive gearbox to the car, it fairly straightforward and will save a lot of
wear on the engine. Also if you haven't already got one fit a thermostatically
controlled oil cooler now!
Hope this is of some help,
Dave B
72 BGT V8
76 Midget
Date: 08-Aug-1995 11:03am
From: Dave Brooke
BROOKED
Tel No: 01923 664574
Subject: Re: Engine Characteristics (1500 Midget)
|