There’s no such thing as enough horsepower.
Only enough to thrill temporarily, but the hunger for more
always returns. There’s no sense in me trying to hide
from the modding bug, it was time to tear into my 350Z. Headers,
mild cams, and a new intake plenum should help me get my fix,
right? After all, it’s about shaving every possible
second off a lap time. My goal was to reach the 300 rear wheel
horsepower mark, and have a smooth, strong power band kick
in no later than 3000 RPMs and just keep going.
Now
before I get into the nitty gritty of the installs and product
reviews, I have to give a HUGE “thank you” to
Aaron Bunch and his group at ATS Racing (www.atsracing.net).
Being primarily an MR2 shop, they bravely took on the task
of the headers and cams – both of which I wouldn’t
dare pursue in my 2 car garage. Aaron provided a baseline
dyno and interval dynos after each modification was complete
to provide me with the most accurate results possible. He
called to keep me informed of the progress, and didn’t
mind my visits to see how my “baby” was doing.
ATS is on of the few shops I’ve dealt with that I completely
trusted and felt assured my car was receiving royal treatment.
So thanks again, Aaron, for all your work!
HEADERS:
For the
headers, I decided on the XERD long tubes. I liked the less
radical bends and the fact that they were the only long tubes
on the market (blame that on the V8 mentality I’ve had
for years). For added finesse, I had them coasted with an
aluminized ceramic coating, inside and out. Added protection
and better air flow certainly helps. The power was right in
line with XERD’s claims of 17 hp. After the dyno, I
had an extra 16 hp and 14 foot pounds of torque at the wheels.
Now that’s a good start!
As far
as the sound goes, well, this is one VERY loud 350Z! The mild
rasp I had before with the B&B exhaust now seems 10 times
louder, and above 3000 RPMs, the car screams like a banshee.
So much so that I’m now looking to replace the B&B
with a true dual system that includes at least two resonators.
I might even go with something custom to ensure I get exactly
what I want.
CAMSHAFTS:
This was
a tricky decision, because I wanted something fairly mild
and something that would work well with a supercharger later
on (just in case), but also wasn’t going to require
major retainer, lifter, shim, etc. changes. The only plausible
solution for me when I was shopping was the NISMO cams. I
ordered from Performance Nissan (Thanks for all your help,
Jenny!), and these cams advertise 13 more hp at the wheels.
From what Aaron told me and from what I saw, the install is
NOT for the weekend mechanic. Different torque specs for each
cam and major engine disassembly made it a very involved job.
When all
was said and done, the dyno results were a little disappointing.
A gain of 8.5 hp and less than 1 foot pound of torque were
added on the upper end of my now smoother power band. Initially,
the car had some idling issues; however, I did not get my
idle raised, as suggested by Nissan. For only 8 ponies, I
wanted to at least keep the sound of a cammed car. After a
month of driving, the ECU seems to have adjusted well, and
any idle problems are virtually gone, but when they do creep
back up, a quick turn on of the air conditioner bumps up the
idle perfectly.
CRAWFORD
PLENUM:
I ordered
the new Version 5 plenum from Doug Crawford, powder coated
in silver. Upon arrival and inspection, the exterior looked
amazing, but some of the interior welds and the warp in the
plenum itself worried me. I wanted to ensure the smoothest
possible airflow into the engine, so Brinks Race Craft re-welded
and flattened it perfectly for me. Now don’t get me
wrong, I’d still choose Doug’s plenum over the
current competition – something just doesn’t sit
right with me about a plastic piece flexing repeatedly over
time, especially since forced induction isn’t out of
my head. Install was straight forward, although a shop manual
is a good tool to have, since there is a sequence to removing
and replacing the many bolts.
The advertised
gains say 9 hp throughout and up to 17-20 more ponies at peak
power. My results will be updated as soon as I get back on
the dyno, but there are several independent dynos that back
up Crawford’s advertised numbers.
CRAWFORD
STRUT TOWER BRACE:
The stock
brace will not clear the new plenum, and for a month and one
autocross, I simply ran without one. The difference in handling
has not been noticeable; however, having the new bar can’t
hurt. I’ll be running my car with it, but with my other
suspension upgrades, it seems like it’s more a personal
preference.
CONCLUSIONS:
The pursuit
of a naturally aspirated 300 rear wheel hp car is not a short
one. After my cams and headers, I went from a spiky 241 rwhp
to a much smoother 263.8 and 246.0 foot pounds of torque.
Assuming the plenum provides the advertised power, I’m
sitting right around the 280 mark. Not quite my goal, but
still 40 more ponies than I started out with, and now my power
band is surprisingly smooth and keeps on climbing right on
through redline. If I had it to do over again, I would have
researched a bit longer and waited for a few more options
in cam choices to come out. It’s still a BLAST to drive,
and I keep thinking to myself, “It’s not supposed
to be this easy to break loose a set of 19x9.5 inch tires,
is it?”
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