Whats up again everyone I've got a question regarding intake
manifolds.. I've got a '79 Trans Am with an Oldsmobile 403. It's got a
few mods such as headers, cam and exhaust but its still sporting the
stock aluminum intake (at least i think it's stock the casting # is
22528212). I've heard the Performer manifolds don't offer much more
power than the stock Olds. Anyone have experience using both?
I don't remember what manifold I replaced the stock one with anymore,
but it was a huge improvement, as the stocker is about the worst thing
ever. When you take the carb off, you'll see why.
It was either an Edelbrock or a Weiand. Even the idle improved. Oh, BTW,
my stock intake was cast iron.
I had moderately ported heads, a mild Mondello cam, the new intake was
put on before almost anything else was done to it, headers and small
turbo mufflers. The stock qjet was worked on by a Olds carb expert, and
only requires slight rejetting to be dead on.
And a distributor recurve will be needed to have it even run halfways
decent when you do work on the heads.
I think (It's almost 20 years since I stupidly sold the car)when it's
all done, the timing was 8 or 10 deg BTDC vs the stock 16 or 18, and the
total timing was best at 36 degrees.
Thanks for the info.. after checking online Ive found out the intake on
my engine was made for the '85-'90 olds 307. Anyone know anything
about this manifold? I don't know why the previous owner of this TA
would use this intake on such a worked engine. I wonder how much of a
performance gain I'll see if I bolt on an Edelbrock or Weiand?
As I recall, all the 307's were dogs performance wise, I would guess
that anything using the same intake would get significant performance
increase. With the exhaust already modified to breath better you should
be able to get some good performance increases with a new intake if you
make the needed timing adjustments to take advantage of the increased
One thing you want to keep in mind is that any intake that is much
taller than the stock manifold will give your 'shaker' the squeeze when you
slam that hood down.
As far as your current manifold coming off of an Olds 307, thats not
unusual for Olds... cams are interchangeable in a huge selection of the of
V8's and valve covers.
Another interchangeable part is using heads off of a 350 Olds from the
early 70's. The 350 heads have a much smaller combustion chamber which will
boost the 403 compression ratio to approximately 9.1:1. The only machine
work required is boring the head bolt holes as the 403 has larger bolts.
One the manifold I used (a Weiand or Edelbrock, can't remember anymore),
it was about one and a half inches higher, we got some off by machining
down the carb mount pad, maybe a quarter or three-eighths of an inch,
and by playing around with the hood, we got it to shut without looking
totally ridiculous. I never got around to hacking some height off the
air cleaner, like one I saw did. They cut it down an inch, and then
brazed or welded the lip back on. Too much work. They used some oddball
paper element for an old foreign car, it fit perfectly.
If I would have been smart and kept it, I was going to do it when I had
the front quarters rehung, and the whole car painted.
OK, I have two questions on this topic; first, how do you "re curve"
the distributor and second, "There are companies out there now that
make full air cleaner assemblies to lower the stock so that a higher
intake such as a Performer RPM or Torker can be used." Who are they and
do they have a web address?
The company is called WFO Performance, website is
Talk to Larry, everyone I know thats used the kits have been incredibly
impressed, not real cheap but better than mounting your scoop to hood or
You change the springs and the weights inside. Contact Mondello and they
can give you the info you need. If the distributor is an HEI, the
weights are probably stuck and all rusted up from arcing through the
rotor and then through the weights.
I have no idea who sells the air cleaner..
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