I've been asking various questions to the list regarding building my
new motor. These are my plans right now. I had sent a note to someone
asking about advice and parts, and I realized that it's a pretty good
summary of what I seem to have learned. If you are in the middle of
building a 150-180 hp MGB motor, a lot of what I have here may be of
interest to you (though you've likely read these various bits
separately).
If you have any critique of my plans (why am I wasting money doing
that?) or other useful advise, please let me know. I'm tired of
rebuilding my motor every 6-months to 2-years.
About a year ago I supercharged my MGB-GT. It was great fun, I boosted
the power from 75hp to the ground up to as high as 110 (though I only
consistently saw about 100-103). The story of that venture is at:
http://www.red4est.com/jasaside/blowart/blowart.html
It was what I euphemistically refer to as a "learning experience". I
made a few mistakes and the long and short of it is that detonation
busted a piston ring, as well as doing various other bits of damage to
the motor.
http://red4est.red4est.com/lrc/pix/predetpistons/
I've had the crank reworked by Armando at CCR, I have a brand new set
of venolia 8.0:1 pistons, I have a cam grind specified by Hans
Pederson for the blower, and ground by Dema Elgin. I'm trying to go
through and make sure that I don't skimp on anything that is
important, yet I don't want to waste money on gold plated unobtanium
parts, where they aren't needed.
The car will be a daily driver that sees regular tracktime as I
instruct with various clubs:
http://www.red4est.com/jasmine
My goal is a reliable 105 hp to the ground. I intend to normally shift
around 6000 RPM, occasionally going as high as 7000 if it will save me
a couple of shifts at the end of a straight. I'd like the parts to be
designed to handle the stress of 120 hp to the ground, and 8000 RPM.
I have a more expndable car for racing:
http://www.red4est.com/miata
I've already installed a ford type-9 five speed tranny.
I've also already installed a significantly uprated radiator.
I have a Moss UK baffled oil pan
I'm currently considering, or shopping for these various items:
Fidanza flywheel $310
Pauter (or equivalent rods) ~$700
Light (or multiplate) clutch assembly $???
Ported Aluminum head. I briefly had a ported iron head on it, which
made a lot more power than the stock head, unfortunately due to the
combination of a water leak and a busted temperature guage, that head
cracked and I'm back to the stock one. Things I've read in Burgess'
book lead me to believe that an aluminum head may be more resistant to
detonation and pre-ignition than a cast iron head. It may also be
cheaper to get ported as it takes a little less time to grind away
aluminum than iron.
I am looking at moving the oil cooler from in front of the radiator to
immediately below the stock location, and possibly uprating it as
well.
I have read in several places that it is not worthwhile, or advisable
to do the uprated oil pump modifications.
The question that brought me to your site was that of valve train. I
had been planning on deferring uprating pushrods and rocker arms until
after I had done some testing on the motor, but as I need to buy new
tappets anyways, I should at least deal with those, and come up with a
plan for the rest. I was pointed to some very sexy lifters at:
http://www.schubeckracing.com/flatultralight.html
But I feel that the $400 they would cost may serve me better in other
areas.
For suspension, I was going to upgrade to the coil-over kit, which is
currently on sale at Moss (I've got a friend who may even be able to
improve on that for me) and install tubshocks in the rear.
I'm looking for a 1" adjustable front swaybar. When I installed the
decambering bushings I needed more bar than the 7/8" Hopkinson one I
had on the vehicle and have stiffened it by the expedient of clamping
a second bar on so that it doesn't bind.
http://red4est.red4est.com/jasmine/jaspix030607/swaybar/
This allowed me to keep my rear wheels on the ground, leading to
excessive tramp exiting turn 11 at Sears Point. I'll probably go for
a lotus link arrangement to locate the rear end and prevent tramp.
I read a very interesting article by Marc Sayer, where he described
how the positioning of the rear spring mounts lead to designed in
roll-understeer. I've contemplated de-arching the springs and lowering
the rear spring mounts to correct this issue.
I would love to also install a narrowed ford 8" rear end with limited
slip and disc brakes, but I fear that is beyond my current budget,
though it may be added later as either my debt load or sanity
decrease.
I've cut away the front valence:
http://red4est.red4est.com/lrc/jasmine/jaspix/jrb/ssscbds/pict0071N.jpg
which gets plenty of air to the brakes, using the porterfields, I've
not had any problems with brake fade on the track. By the way, the
grill badge in the picture is for the SSSCBDS, the club my dad was in
when he raced MGs in the 1950's back east.
Larry Colen
--
"Nothing says Badass like tearoffs" - Becky Swafford
Larry Colen lrc@red4est.com http://www.red4est.com/lrc
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