---- "Robert M. Lang" <lang@isis.mit.edu> wrote:
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On Wed, 30 Nov 2005, Gene Holtzclaw wrote:
> I would like to know from those who know much more than I ever will, what
> connecting rod is best if you are attempting to build the ultimate street
> driven TR6 engine?
The best rods are Carillo. Period. All the top racers run them. They are,
however, just this side of insanely expensive at $333 _each_ when I last
checked.
The stock rods are pretty good unless you build a lot of boost and/or
compression (like more than 12:1 c/r or more than 9 or 10 pounds of
boost)
--------------------------
I'm going to toss my opinion in here, since I've been thrashing turbocharged
cars around for a while now. First a 951 Porsche, now Fords. If it was me, I'd
be spending my money on balancing the stock components, staying with a mild cam
with little overlap (the stock cam will be fine, believe it or not), and run
staged boost control that'll limit you early in the revs. Let the natural
torque of the engine get you into the 3-4000 rpm range ,with say a 2-3 psi
limit then bring on the power-adder up to a 5500 rpm redline. You'll love the
feel of the car, and it'll last a long, long time for not too much cash. You
won't be so apt to break other stuff in the drivetrain, either.
I have in excess of 230 hp now from my little 4-banger ( I really need to do a
quarter mile to see just what it is) and find myself happily short shifting
before I even get to 5 grand.
I have given this considerable thought since I have all the stuff here to do a
turbo TR6. Since my latest 1976 car has A/C the issue is where to put it. I'm
thinking of running sans distributer, fabbing some throttle body injection
using Megasquirt and locating the turbo on the driver side. Dollar for dollar
forced induction (turbo or supercharging) is the cheapest way to reliable
streetable 200 HP IMHO. The downside is a weight penalty and added complexity
of course.
If you want a boosted motor to live, controlling detonation is your primary
concern. Adequate fuel and having a good handle on your spark timing is
crucial. Before I went with high buck rods I'd be getting top quality forged
pistons in there. The more initail compression ratio you have the harder it is
to control detonation at mid throttle/high load when the boost comes on.
Programmable ignition or at least a boost referenced spark retard should be
considered on a motor sporting over 8 to 1 initial CR.
I'm presently driving a turbo Merkur with a homebuilt MegasquirtnTFI
controlling fuel and spark, and am building a Thunderbird turbocoupe with a
twin turbo 5.0 (As soon as I get this 74 TR6 finished and sold!)
I won't have $8,000 in both cars for high quality street cars once they're done
since I'm using turbocharging on a stock engine rather than buying a bunch of
hi-po parts and machine work. As a lot of you know, that adds up in a hurry!
(Both the 2.3 and the 5.0 come stock with forged rods and pistons out of the
box).
OK, that's my spiel, take it for what it's worth. Best of luck on your project,
it sounds like a neat car!
Jim Franks my website has some megasquirt stuff on it:
http://users.adelphia.net/~jimmble/index/index.html
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