Stan---If the ultimate goal is a TR street engine, with minimum fussing,
that makes around 160 HP, I think that some sort of forced induction is
the way to go. All that is necessary is a decent engine and drive train
to start with. If you suspect that your frame may have been compromised
from rust or abuse, well then there's that.
Kits that return around 5-6 lb. are fairly safe, if the stock
compression ratio hasn't been raised, or at least not exceeding 8:1.
More later on this.
To make "Lots of Boost", like approaching 8 lbs. or more, requires that
steps be taken to stay out of detonation. A slow burning flame front can
be achieved thru high octane fuel, or some method of cooling off the
charge of the incoming compressed air/fuel mix. Spark advance control is
another good way, like ignition boxes that sense boost, and retard the
spark to whatever is (adjustably) pre-programmed into it.
If you want to add a reasonable performance cam when the engine is down
for refreshing, then know it can change the low end fuel needs and
character of the idle. Not at all bad, and the exhaust burble is kind of
nice! As in most cases, more power is available from mid to high rpm, at
some expense at the bottom.
Many good books are written about the subject, giving infinitely more
detail than the thumbnail sketch above.
If you want a TR engine that makes lots more power and don't want the
fussing, "go with the force!" It is said that this sort of an engine
will last longer, because it is less stressed during most of its run
time.
...But if you want performance that is more old school and like to be
tinkering a lot, go with the more traditional method. The dollar costs
are about the same. They both can be enjoyable! Either can provoke a
WOW!
Dick
From:
stan.foster@hp.com(Foster, Stan)
In the past we have discussed the pros and cons of engine tuning for
fast street use via new cam, 9.5:1 compression etc vs just bolting on a
supercharger. It seems that the cost for both is about the same when you
factor in the cost of parts and machining of the traditionally tweaked
engine vs the cost of the Supercharger (ie in the $3500 to $4000 range)
for an equivalent increase in HP.
My question is whether this is really an either/or question or is there
a hybrid solution where the engine is upgraded with cam/head and then
the supercharger is added for additional power. My reasoning is that
even if the end goal is to supercharge, the base engine has to be in
good condition so if you are going to all the trouble of pulling it out,
refurbing it with new bearings and possibly more (pistons, rings etc)
then why not upgrade it at the same time as long as you don't exceed any
limits that the supercharger may impose (eg the compression ratio). Cost
can be mitigated by a phased implementation, mild tune to start with,
add supercharger later when cash flow allows.
Thoughts ?
Stan
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