Hey folks,
Had the week off last week, so I decided to install the exhaust header and Monza
system that I've had stashed in the basement. I ordered the parts from VB a
year ago, but never had the time until now to do the install.
First off, you should know that the air pump and other emissions stuff was long
gone on my car before I bought it. Also, I found that the quoted ignition
timing setting of 4 deg. ATDC made the poor thing positively anemic. I changed
this to the UK spec of 10 BTDC and found a lot more horsepower and no more
overheating. This was done two years ago right after I bought the car.
However, I still found the performance less than stellar, hence the new exhaust
system.
First off, after I tore off the old exhaust, I found that the new header would
not go in unless the air conditioning compressor was removed. Since this had
long since died, I removed it and left it off (anybody want it?).
When I went to mate up the header to the head, I found that it would not fit
due to pipe no. 3 hitting the steering wheel shaft. Hmmm. Now what? Took the
header up to a local muffler shop and talked the owner into heating up the
offending pipe with a torch and bending it out of the way. Cost: $10.00. Took
the header back and tried to install a second time. Now finding pipe no. 2 just
touching the inside frame rail. Pulled the *&%$@ thing back off and took back
to the muffler shop to have some more bending done. Cost: $0.00. Finally got
the header installed.
Now the exhaust. Once I realized that there was no way that I was going to
fabricate a pipe to replace the cat. converter section, I bought a piece of flex
pipe and clamped one end to the header and the other to the expansion chamber
section. This held long enough for me to get the car to (my now favorite)
muffler shop, where it promptly fell off. There the owner bent and fabricated a
pipe section to replace my bodge job, and replaced all my clamps with welds. He
also found that a bracket was not positioned properly from the factory, which
caused the exhaust system to hit the body. He cut and repositioned that. Also
found that the r.r. coil spring had shifted off its mount, so he compressed the
spring and moved it back in place (so that's where the noise was coming from!)
Also fitted rubber exhaust hangers from a VW Rabbit as they kept the muffer from
hitting the underside of the car on bumps. Cost for all this fiddling: $30.00.
Impressions: First thought was that I would have gotten the same sound by
drilling a hole in my muffler. Where my TR4 sounds rich and mellow, this sounds
buzzy. However, there has been a definite increase in power. I was worried,
since I had heard stories of horsepower decreases after fitting a header. Not
the case with this system. The car revs quicker, and the higher rev. range is
more usable. Also, the throttle response feels much better. Also, after a
week's driving, either I'm used to the noise or the system is breaking in, cuz
the buzzing is turning into a richer hollow sound.
Verdict: Worth the effort if you are looking for cheap, (almost) bolt on
horsepower. Not a straightforward install, but something that a TR7 really
needs!
David Rupert
75701.242@compuserve.com
1967 TR4A (rigid axle)
1980 TR7 Convertible
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