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MGB performance (was Fast and Furious)

To: MG List <mgs@autox.team.net>
Subject: MGB performance (was Fast and Furious)
From: Larry Colen <lrcar@red4est.com>
Date: Mon, 2 Jun 2003 09:32:34 -0700
According to my friend Charlie Rockwell who used to run a dyno tuning
shop, a typical chrome bumper MGB would put about 65 hp to the ground,
a Rubber Bumber MGB puts about 50 to the ground. 

The previous incarnation of my motor: 8.8:1 compression, balanced,
Elgin, "show room stock cheater cam", K&N air filters put about 75 hp
to the ground. I suspect that with what I've learned over the past few
months, I could wrangle a few more horsepower from an identical motor,
but just a few (<5).

I've not yet gotten the blower on my current motor dialed in. It's
been a learning process. I lowered the compression to 8.0:1, and other
than that it's the same as the previous motor. Unfortunately the cam
does not work well with the blower. I need to redo the bottom end, 5
weekends at the track (probably close to 1100-1200) miles, combined
with predetonation problems and my oil pressure is way too low, I also
noticed a rear mainseal leak. I hope to get the motor out and
disassembled ASAP.

Anyways, I've seen 100-109 peak horsepower to the ground with this
motor. The dyno doesn't display torque, and I haven't figured it out
yet. This is almost as much horsepower as a Datsun 510 in Improved
Touring trim puts out. I can now nearly keep up with first generation
Rx7s and Miatas on the straights.

I do tend to keep up with most traffic through the turns, but I'm
afraid that probably has more to do with my having a 12+ years
advantage in tracktime on most of the other drivers in the rungroup that
I play with.

My trip to Sears Point ^H^H^H^H^H^H^H^H^H Infineon a week ago was not
as succesful as I had hoped in terms of Jasmine beating up on all the
other cars. First of all she suffered from the disadvantage that I
hadn't driven the track in a couple years, coupled with the fact that
I had never driven the NASCAR configuration (the chute rather than the
carousel).  I was also having trouble with the oil pressure dropping
after running her hard for a while. 40-50PSI was low but doable, but
when I was seeing 25 on the straights, I got nervous. Which is too
bad, because I was having a lot of fun playing with someone in an X
1/9 one session.

The good news is that I was experiencing severe axle tramp coming out
of turn 11. Why is this good news? Because that means that I've got
the suspension sorted out well enough that she's actually getting the
power to the ground coming out of turns. In case anyone is interested
in low-bucks suspension tuning techniques, I stiffend the front end by
taking a sway bar that I had lying around (I think it was from an Rx7,
I think it was about 3/4") cut the ends off, and using 1" aluminum
tubing as spacers, clamped it to my existing swaybar. Not calibrated,
hard to do repeatably, but I was able to confirm that more front end
stiffness improved handling by only spending about $20 on aluminum and
hose clamps.

My last couple of sessions, rather than taking Jasmine out, I did lead
and follow sessions with my students, driving a friend around in her
'89 Honda Civic Wagon. At the moment the suspension on the car is
stock, and the tires not particularly impressive. Even so, it still
handled a lot better than the '84 and '85 civic wagons I used to take
out on the track, and truth be told, with equivalent tires, would
probably out handle Jasmine, even with the work I've done on her. It
wasn't quite as "comfortable" to drive hard through the twisties as
my MGBGT, but I'd wager it could turn the same numbers. 

Jane also got tired of barely going fast enough for the open road
races that she likes to drive in, so she swapped out the motor for a
150hp motor (10-20 more than my supercharged MGB) out of a Honda Del
Sol. 

The moral of a story is that with far less effort, one can make a
Honda Civic Stationwagon, out accelerate and out handle an MGB. In
doing so it will get better gas mileage and be able to carry 4 adults
in comfort, 5 not too uncomfortably, and still have room in the back
for enough groceries for a sumptious meal for everyone inside.

On the other hand, on two of the five weekends I've taken my car to
the track this year, I've had people come up to tell me that I had the
coolest car there. I also think that on five of the five, I've had
people come up to me and comment that MGBs just don't accelerate the
way mine does.

   Larry

On Fri, May 30, 2003 at 09:19:42AM -0700, Max Heim wrote:
> Larry C. has reported on several dyno sessions sorting out his supercharged
> GT. Stay tuned for his next installment.
> 
> on 5/29/03 10:48 PM, MGBracer80@aol.com at MGBracer80@aol.com wrote:
> 
> > I have had many chances to rice out a civic or a toyota, But why waste my 
>$$$
> > when I have a MGB that might not be faster. But it sure makes a civic look
> > like a log in the
> > shitter.  Nothing makes my smile bigger then smoking a ricer in my bloody
> > British car .      I have been wondering if any one has ever put threre "B" 
>on
> > a 
> > dyno?
> >  If so, How did it turn out.
> 
> 
> --
> 
> Max Heim
> '66 MGB GHN3L76149
> If you're near Mountain View, CA,
> it's the primer red one with chrome wires

-- 
I've found something worse than oldies station that play the music I used to
listen to. Oldies stations that play the "new" music I used to complain about.
lrc@red4est.com                                    http://www.red4est.com/lrc

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