Greg:
The big problem with the TR6 motor towards the end was the
anemic compression ratio. If you want a nice pop in torque, shave the
head to get the compression up to between 9.5:1 and 10:1. Make sure your
anti-run on valve is working because the engine will probably start to
run on when you raise the compression.
For torque, you want lots of lift but short duration on the
camshaft. The higher lift rockers are a good idea. You can retard the
timing on the camshaft by up to 4 degrees to improve torque as well,
although this comes with a price on the top end.
A cold air kit of some sort will help, as will K&N filters. The
improvements are small, but they are easily added as they are in the
"bolt on" category.
I would replace the muffler with a cyclone sonic turbo or a
Dynomax Super Turbo. While this does not increase your torque directly,
it will give you more power without costing you any torque, so it is a
good tweak to consider if you don't want to go the camshaft route for
more power.
You are never wasting your money in the performance category.
But a strong motor is expensive, so you need to ask yourself, how fast
do I want to go?
Vance
-----Original Message-----
From: owner-6pack@autox.team.net [mailto:owner-6pack@autox.team.net] On
Behalf Of Greg Perry
Sent: Saturday, July 01, 2006 4:09 PM
To: 6pack@autox.team.net
Subject: Camshafts for low end torque
Hello List,
First, Happy Independence Day weekend USA!
Since I have a stock 72 TR6 with carbs, A type overdrive and dual
exhaust, the highway rpm range is from 2100 to 3000 depending on traffic
and road conditions. I am interested in maximizing the lower torque
range from 1200 to 3000 rpm. I am not interested in HP ratings. Torque
gets you down the road. The web site Triumph 2000 Tuning website
http://www.kvaleberg.com/t_tune.html
has an extensive list of camshaft profiles for PI models. It seems
that the stock camshafts are better suited to my needs. The pre 72 USA
TR250/TR6 camshaft (10/50 50/10) has a power band 1500- 4800 and the
currently installed 72 onwards USA camshaft (18/58 58/18) has a power
band 2000-5000.
1. If the pre 72 camshaft is put into a stock 72 motor, what are the
opinions from the list about a possible torque increase and performance
if any?
2. Would I get a similar result by increasing the valve lift with
1.55:1 roller rockers on the currently installed camshaft 72 onwards?
3. Any other suggestions for increasing the low end torque?
4. Or am I just wasting my time and future money for a small
performance increase?
I am only considering options available in the future if/when I
need/decide to rebuild the engine. I could collect the parts when they
are on sale in the future. I will probably do a little autocrossing at
the local scca events after getting the suspension up to the task.
Thanks,
Greg Perry
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