OK - so the 327 was fun! The cam (Comp Cams Xtreme XS274S-10) has
a nice lope, breathes well from 2200-6400 rpm. But cruising in 5th
at 65 mph is not very much fun. Bottom of the torque curve at cruise.
Sure, I could have backed off on the cam duration/overlap, but then I'd
have less power - and I have gotten used to the power as it is. The
acceleration at the top end just isn't in the "scary" region where I want
I did add a 700 cfm Holley Projection TBI setup to the engine, and now I can
cruise even down at 1500 rpm, and it pulls much better from a 2000 rpm cruise.
Oh, another problem developed. My ignorance, bad luck and some severely
leaking (into the manifold) Holley carbs (into the manifold) caused the
cylinders on the 327 to get fuel-washed. So now the 327 is an oil
burner. A quart of 10W40 every 500 miles. After 4000 miles,
it's a lost cause - worn rings and/or cylinder scuffing.
So what does a gear head do? Get another engine! And of course,
it has to be bigger and better than the last one! MORE POWER!!
I've come to realize that how fast an engine revs has more to do with the
torque it's putting out over the rpm band than the stroke of the engine.
Sure, the 327 has a shorter stroke, so you'd think it'd rev quicker than
a 400, but the 400 has a bunch more torque to accelerate the car.
Plus it breathes better (larger bore). If you're happy with a 6300rpm
redline (I am) then a 400 will do that - with a bunch more torque and power.
Dave Williams at "Maximum Overdrive Racing Engines" had a 2 bolt 400 "509"
casting (high nickel content) block that was standard bore. He took
that and built a balanced and blueprinted shortblock that'll work out to
10.5:1 with 65 cc heads...
Well, the old 461 casting "camel hump" heads just wouldn't do the 406 justice.
So a set of 215cc intake runner Canfield
heads were ordered... These are similar to the 220cc heads, but don't
require offset rocker arms.
Oh, that problem with washing down the cylinders with the Holley?
Fixed with a good 650 DP carb. But that's going by the wayside since
I bought a used 700 cfm Holley Pro-jection 4D throttle body injection kit.
The 4D computer will be replaced with a Megasquirt
computer in the future.
for the Z - 327 Chevy
I had seen and driven hopped up and Turbo'd L6 240 Z's. Mine was
stock engined (although it had 72 SU's and 2-1/2" exhaust.) My desire
for the low end torque I grew up with (70 Camaro with a warmed over 327),
and the drivability issues (having to be in the right gear - O.K., I'm
lazy) and cost of hopped up L6's made the decision for considerably more
displacement. For the street, I just like normally aspirated high
displacement engines. I have a 92 Eclipse GSX I've modded to run
at 15psi, and although it is fun to drive, I don't like having to be in
the right gear whenever I want to accelerate. I keep the revs low
unless I'm really concentrating on going fast and have the opportunity
to. High revs draw attention and I don't like that.
I know how to work on Chevy small block V8's, and had a good background
in hopping them up. Plus some nice Chevy heads, etc. on hand...
The Chevy small block may be heavier than say a Ford small block, and the
distributor placement may not be as good, but I'm not particularly well
versed in the Blue Oval, nor the Mopar stuff for that matter. Plus
the fact that the JTR manual is done for the Chevy - he's already done
a lot of the engineering.
The after market for the Chevy is larger, although the Ford small block
is getting quite a bit better in the past 5 years or so since I built my
Displacement? Sure the 350 is popular, as is the 383. I figured
that a 327 built slightly warmed over (good throttle response from 1500,
top usable rpm at 6000) would have enough torque. Plus I just like
the way the 327 winds up quickly. Better rod to stroke ratio (with
stock length rods) than the 350. With the 66 cc heads I have, and
a flat top piston (for good quench), it works out to a 9.7:1 compression
motor. Just right for pump gas.
BTW, a 327 bore 0.030" over (like mine) works out to 5435 cc's. So
now it will be a 540Z!
Copyright 2003, Peter J. Paraska. All Rights
reserved by Author. Please email me for free permission to copy. The purpose of this site is to document what I have
done to my car and why. Your mileage may vary. I am not responsible
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Use at your own risk.