I have a "Special Tuning Guide" for the MGA 1500 and 1600. Since my car hasn't
been on the road in 12 to 14 years, I'm certainly going to do a full rebuild on
the engine.
With all this money invested, I want to get a little more HP for the buck, so
its
my plan to bring my car to stage 3A (I think that's correct, I didn't bring the
book with me to work). Anyway, what that involves is:
1 Porting and polishing the head
2 a Cam which is other than stock and optionally a different ignition
timing curve
3 Flat topped pistons, which give a 9:1 compression ratio, and rich carb
needles.
RE: 1 Porting and polishing.
I have a 1622 head on my car, so the porting and polishing will be on a head
with
bigger vavles, so I should get good flow. This is not a problem. They give
enough information in the guide, and I've read some books on the subject of
porting and polishing.
RE: 2 Cam and advance curve
A friend of mine recently installed a cam in his MGA 1600 and noticed a good
increase in power with no decrease in drivability. I'll compare the specs of
his
cam to those in the special tuning guide. I assume that they'll be pretty
close.
With the installation of thise cam, however, the guide says that you can keep
the
curve you already have, OR for a little more power, you can install a
distributor
from a Reiley (sp?) 1.5 which will have the correct curve for this Cam. The
problem with this is that the part number given for the distributor is an old
MG
part number. Is there any way to referece the specs of this part number?
RE: 3 Flat topped pistons and CC carb needles.
I know where I can get my hands on the 1500 flat topped 9:1 pistons. They're
still in the original bow, with wrings and wrist pins. They're forged, not
cast.
The guide says that if you install these, you must use connecting rods #
xxxxxxx.
Again, its an MG part number, and it doesn't say what the difference is between
those rods and the stock rods used with the 8:1 pistons.
I would ASSUME that the difference has something to do with strength/resistance
to cracking. I don't know if a good machine shop could recondition the rods
then
shot peen (is that the term, I forget) them to harden them. What I'd REALLY
like
to do is get the specs or at least a description of the rods referenced.
The carb needles are, obviously, a no brainer.
The extra 10 HP (from 70 to 80) would be nice, but I'd hate to install all of
this stuff on an engine, only to have the rods let go 10K miles after its on
the
road. 10 HP might not seem like much, but its about a 14% gain.
Thanks for any info you can give...
-Al
|