Seth, thanks for the insight. I'm surprised that adding the supercharger is
having such a dramatic affect on the chassis. I know these are traditionally
weak areas anyway but I was expecting that adding the SC would bring the unit
up to the same level that the early PI TR6 was (150hp) and no major mods would
be needed to an otherwise intact frame. I may have to reconsider that as I plan
to take the diff out for a refurb this winter..
Stan
-----Original Message-----
From: Seth Glassman [mailto:superchargedtr6@gmail.com]
Sent: Saturday, October 21, 2006 12:11 PM
To: Foster, Stan; 6pack
Subject: Re: Engine upgrade vs supercharging
Stan,
You're not far off in your rationale. I did my S/C project 3 years ago and
am very satisfied although there was a sorting out process especially with
the SU carb and running way too rich. It still does but much better with
the installation of the Petronix Second Strike unit.
I would definitely NOT do anything to can the original compression ration.
On later model 6's 7.75 :1 is fine. I don't recall any problems at the
higher ratios on the earlier 6's though. I installed a little hotter cam
then stock from Integral Cams. They also have a grind specifically for the
TR6 S/C install.
An engine rebuild is definitely a good thing beforehand and a piston bore of
.20 over is OK too. I would definitely "bulletproof" the bottom end with
upgraded everything. I did with upgraded con=rod bolts and bearings. I wish
I had had the funds for upgraded pistons, rods and rings. Mine were all new
but stock.
There are other issues which I didn't realize at the time but have learned
since. There is alot more torque forces applied on the right side now since
adding the S/C. I've had to reinforce diff mount brackets with are
gusseted. I also found that with the tube shock conversion installed, my
the welds of the diff crossmember to frame rails have broken on the right
side and the crossmember itself on the right side has a 4-6 inch crack up
its arm toward the top flat cross area where the diff attaches.
Fortunately, my friend who started RATCO, making new TR6 frames, has come up
with a new crossmember kit and coil over shock kit for me to install. This
should reinforce those areas and take care of the "unnatural" forces on the
frame from the tube shock conversion (as reported here a few weeks ago).
Well, that my experience. Hope it helps in your decision
Regards,
Seth Glassman
'76 (Supercharged) TR6
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