250 WHP Supernatural 3.4 Build (Page 1/36)
La fiera OCT 07, 11:04 PM

This build is dedicated to those that don't give up on the unconventional builds like keeping the iron heads instead of
swapping for the aluminum heads, or discarding the 2.8/3.1/3.4 pushrod engines to install a SBC, 3800SC, 4.9 V8 or 3.4 DOHC
or whatever other engine but the original engine type.
I have no problem with the engines mentioned above, but for me personally; I want to prove to
myself that with some ingenuity, time and some resources I can build an engine that will perform in my Time Trial Duntov Fiero.
The goal is 250WHP out of a Naturally Aspirated 3.4 iron head engine with explosive mid range and killer top end.
This will be on a stock bottom end, head work, custom cam and Intake and a stand alone ECU.
Note: Some items information will not be disclosed.
The weight goal with the engine must be below 2200lbls
to have a competitive power to weight ratio.

So, here it goes:
Spadesluck OCT 07, 11:28 PM
Watching......
BillS OCT 08, 12:30 PM
This is kind of like watching a build of a Ford V8-60 flathead where one just asks "Why?"
La fiera OCT 08, 01:30 PM
After looking with what I had to work with it, it was obvious that my 250WHP @ 6000RPM+ goal was impossible with
factory items. Specially the stock intake and exhaust manifold, camshaft, TB, "Y" pipe and exhaust pipe diameter.
Some members have past the 200+WHP succesfully with stock components but those ponies where at low RPM, and the torque was
produced at very low RPM. Good combination for the street, but not for the road course where the engine
will spend most of its time between 3500 to 6800RPM. So, we had to come up with a system to put the power in that
RPM range but it was also important "how" that power was delivered withing that RPM window, it had to be EXPLOSIVE....!
With that idea the Supernatural concept was born!
Intake Manifold:
Size and shape of plenum and runners, injectors location, and TB size and style
was designed to the RPM window in mind.

Heads
Port work and valve size was designed to match the intake manifold, exhaust header and Y pipe flow capabilities.

Camshaft, Lifters & Springs
The most critical parts of the package. Without a camshaft to complement the intake and head combo there is
no sense in installing the head and intake with the cams and springs available over the counter.
A mechanical cam style was chosen over the hydraulic flat tapped and hydraulic roller to get the explosiveness and
top end power capabilities we were looking for. Also the mechanical cam's lash can be adjusted to make the cam
smaller or bigger and that is a plus to match the cam to the track.
The mechanical lifters are lighter than the hydraulics and the ones we used have a little pin whole to provide
the cam lobes with pressurized oil to lube and cool the lobes at the same time.
Aggressive cam profiles call for very aggressive spring rates and the available springs for the V6 iron heads couldn't be
used in our package without having serious consequences. So the heads were modified to take advantage of the plethora
of racing springs and narrow full aluminum roller rockers available for the SBC V8.


Supernatural Top End Package



Next we will compare with pictures some stock vs Supernatural items. STAY TUNNED!!

[This message has been edited by La fiera (edited 10-08-2017).]

Blacktree OCT 08, 01:30 PM

quote
Originally posted by BillS:

This is kind of like watching a build of a Ford V8-60 flathead where one just asks "Why?"


I'm sure the non-Fiero people look at us building up Fieros in much the same way.

[This message has been edited by Blacktree (edited 10-08-2017).]

Dennis LaGrua OCT 08, 09:47 PM
The goal of 250 RWHP from a 3.4L pr engine is a very aggressive one. I've built these engines and even with a turbo have not reached this goal. You can improve the performance but the engine breathes poorly. With loads of boost like 20 psi you might reach your goal but N/A I say no way.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

La fiera OCT 08, 10:05 PM
Stock VS Supernatural Intake Manifolds


Stock VS Supernatural Y Pipe

This Y pipe is being upgraded to a lighter and smoother version

Supernatural Heads



Next, lets start to put the engine together!
La fiera OCT 08, 10:48 PM

quote
Originally posted by Dennis LaGrua:
With loads of boost like 20 psi you might reach your goal but N/A I say no way.



Hello Dennis, the goal of my engine is NO TURBO, NO JUICE, 250WHP NATURALLY ASPIRATED @ 6000RPM. 3.4 PR IRON HEAD ENGINE.
I completely understand your concern in me not reaching that goal, but I'm absolutely sure I can.
So, just be patient and wait and don't ruin the expectation for the rest. Just relax Dennis!


Blacktree OCT 08, 11:42 PM

quote
Originally posted by Dennis LaGrua:

With loads of boost like 20 psi you might reach your goal but N/A I say no way.



The last dyno he posted was 240 RWHP. I'm sure he can find another 10 HP somewhere.

Just because you can't do it, doesn't mean he can't do it.
fieroguru OCT 09, 09:34 AM

quote
Originally posted by Dennis LaGrua:
The goal of 250 RWHP from a 3.4L pr engine is a very aggressive one. I've built these engines and even with a turbo have not reached this goal. You can improve the performance but the engine breathes poorly. With loads of boost like 20 psi you might reach your goal but N/A I say no way.



He is already at 240 whp on a mustang dyno, so there is clearly an opportunity to learn something from him. La fiera is shifting paradigms and that is great!