Corky's engine choice

On Tue, 29 Jul 2003 23:48:14 -0700, Barry S.
wrote:


On additional subjects in this thread, right now there is no one of
whom I am aware that is manufacturing PSRUs for the Ford. Johnny
at Northwest Aero discontinued his, though he still makes them for
other engines, because of low demand. Johnny also used to build the

This was essentially my original point. The Ford, for all its weight
and cost advantages, just didn't generate enough interest/dollars to
sustain the production of a single off the shelf PSRU.

Why?

I can only speculate Barry, but I'd guess that because Chevy had so
many high performance parts, and virtually no on supported the Ford
V-6 in that manner, it just kinda started out slow and then petered
out.

You can buy just about anything in performance from Chevy or a vast
number of racing specialists for the Vortec V-6. It will cost you a
lot more than the Ford in the end, but you can buy things like
Edelbrock intake manifolds, in several varieties, aluminum heads and
even aluminum blocks. It's just that you're paying dearly for each of
those items whereas on the Ford, the intake manifold, timing chain
cover and heads came from the factory as stock aluminum items. That's
why Blanton turned to the Ford in the first place, he was obsessed
with developing a really inexpensive alternative engine that
approached the weight of the typical Lycoming.

There are some problems with using the Chevy parts: The aluminum heads
are really strictly for high performance or racing and are developed
for high airflow and big valves. This works fine if you are always
running around 8,000 rpm, but doesn't work well for idling or
intermediate power. Early aluminum heads used smaller valves and were
better for conversion but they are getting scarce now. Who knows, by
now someone may have developed a head that works for our purposes
again.

Corky Scott

On Wed, 30 Jul 2003 11:44:30 GMT,
(Corky Scott) wrote:

On Tue, 29 Jul 2003 23:48:14 -0700, Barry S.
wrote:


On additional subjects in this thread, right now there is no one of
whom I am aware that is manufacturing PSRUs for the Ford. Johnny
at Northwest Aero discontinued his, though he still makes them for
other engines, because of low demand. Johnny also used to build the

This was essentially my original point. The Ford, for all its weight
and cost advantages, just didn't generate enough interest/dollars to
sustain the production of a single off the shelf PSRU.

Why?

I can only speculate Barry, but I'd guess that because Chevy had so
many high performance parts, and virtually no on supported the Ford
V-6 in that manner, it just kinda started out slow and then petered
out.

I suspect you're probably not far off. The cars the 3.8 went in
generally weren't the "sportiest"..

With the half price redrive and inexpensive supply of engines, what do
you think your installed cost will be?

__________________
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N38.6 W121.4

On Wed, 30 Jul 2003 21:47:09 -0700, Barry S.
wrote:

I suspect you're probably not far off. The cars the 3.8 went in
generally weren't the "sportiest"..

With the half price redrive and inexpensive supply of engines, what do
you think your installed cost will be?

__________________
Note: To reply, replace the word 'spam' embedded in return address with 'mail'.
N38.6 W121.4

I've kept all the receipts for the parts so far and will post an exact
cost summery when the engine is assembled.

As Bruce mentioned, I'm doing things a bit differently (the story of
my project in general I think). I'm using roller rockers, which you
don't have to use and I'm using studs for the cylinderheads and main
bearing caps.

In addition, I bought Northwest Aero's lightweight alternator and
their two pickup distributor, as well as their lightweight and
undersized drive pulley's to keep the alternator rotational speeds
within reason.

You don't have get these things to have a viable engine, most haven't.
I'm trying to keep the weight of the engine down.

I should mention that the roller rockers are the 1.8 ratio rather than
the stock 1.7 ratio. This gives better breathing and, according to
Morana Racing, an additional 20 horsepower. I wasn't sure about using
them as I did not want to be experimenting, but they are a literal
bolt on substitute and don't otherwise affect the engine or
clearances. So I got them because more power, within the rpm
limitations, is a good thing.

Corky Scott

I should mention that the roller rockers are the 1.8 ratio rather than
the stock 1.7 ratio. This gives better breathing and, according to
Morana Racing, an additional 20 horsepower.

Corky Scott
+++++++++++++++++++++++++++++++++++++++++

Uhhhh...
I played rocker ratio games four decades ago. Unless things
have changed dramatically, don't bet the ranch on getting
20 more horses in your app per Morana Racing propaganda.


Barnyard BOb - drag racers wuz us

On Mon, 04 Aug 2003 07:29:18 -0500, Barnyard BOb --
wrote:


I should mention that the roller rockers are the 1.8 ratio rather than
the stock 1.7 ratio. This gives better breathing and, according to
Morana Racing, an additional 20 horsepower.

Corky Scott
+++++++++++++++++++++++++++++++++++++++++

Uhhhh...
I played rocker ratio games four decades ago. Unless things
have changed dramatically, don't bet the ranch on getting
20 more horses in your app per Morana Racing propaganda.


Barnyard BOb - drag racers wuz us

It's going to be pretty much impossible to tell. I won't be running
the engine on the dyno with the original rocker arms, and then
switching to the new ones to verify performance differences.

I'll only be getting the power output as is, and that will be with the
1.8 ratio rocker arms.

I'm not even sure I will be able to have the engine connected to the
dyno. The engine needs some sort of bell housing or plate machined to
take the starter and without it, there is no starter.

If I install the PSRU, which is machined to take the starter, I doubt
the engine will bolt to the dyno. I've never run an engine on a dyno
so I don't know if the dyno itself can motor the engine to get it
started or if the engine must have it's own starter.

One of those details I'll have to find out about when the time comes.

Corky Scott

That is for sure. Corky's rocker arms change will be interesting and I
cannot see anything detrimental to the engine by making this change, but
I too long ago learned to take auto parts mfg. claims of bolt on HP as
sales pitch. Roller rockers have benefits but a 20 horse bump is
significant.

Bruce A. Frank

Barnyard BOb -- wrote:

I should mention that the roller rockers are the 1.8 ratio rather than
the stock 1.7 ratio. This gives better breathing and, according to
Morana Racing, an additional 20 horsepower.

Corky Scott
+++++++++++++++++++++++++++++++++++++++++

Uhhhh...
I played rocker ratio games four decades ago. Unless things
have changed dramatically, don't bet the ranch on getting
20 more horses in your app per Morana Racing propaganda.

Barnyard BOb - drag racers wuz us

BOb

I agere with you. Been down that rabbait trail many years ago also.

Big John


On Mon, 04 Aug 2003 07:29:18 -0500, Barnyard BOb --
wrote:


I should mention that the roller rockers are the 1.8 ratio rather than
the stock 1.7 ratio. This gives better breathing and, according to
Morana Racing, an additional 20 horsepower.

Corky Scott
+++++++++++++++++++++++++++++++++++++++++

Uhhhh...
I played rocker ratio games four decades ago. Unless things
have changed dramatically, don't bet the ranch on getting
20 more horses in your app per Morana Racing propaganda.


Barnyard BOb - drag racers wuz us

On Mon, 04 Aug 2003 16:38:19 GMT, "Bruce A. Frank"
wrote:

That is for sure. Corky's rocker arms change will be interesting and I
cannot see anything detrimental to the engine by making this change, but
I too long ago learned to take auto parts mfg. claims of bolt on HP as
sales pitch. Roller rockers have benefits but a 20 horse bump is
significant.

Bruce A. Frank

There is one consideration. That is valve mass acceleration and
deceleration. If you lift the valve a greater distance in the same
amount of time, good valve springs and good seats become critical. The
higher ratio rocker is a better solution than a taller lump on the cam
since the lifter, push rod and rocker acceleration are not increased.

There was a fascinating talk at AirVenture (at least some of it was
fascinating :-) by a guy from NASA. His point was that if you're willing
to give up some efficiency, you can save a whole lot of cost. For
example, if you're willing to put up with some extra engine weight, or
some extra fuel burn, or whatever, you can get in the air lots cheaper.
The real costs come in getting the last bit of efficiency was his point.

Let's take some hypotheticals:
* An "aircraft style" two seater, 1600 pounds gross, 1100 empty, 160
knots, 9 GPH, 60 thousand bucks
* An "unoptimized" two seater, 2000 pounds gross, 1400 empty, 140 knots,
11 GPH, 30 thousand bucks

I know which we'd all like to have, but which we'd all like to pay for.
I think that one factor is that most of the auto engine planes look much
less than cool, with gunky cowls and radiators and such. If somebody did
a "cheapmobile" and it looked cool...

Ed Wischmeyer

Ed Wischmeyer wrote:
There was a fascinating talk at AirVenture (at least some of it was
fascinating :-) by a guy from NASA. His point was that if you're willing
to give up some efficiency, you can save a whole lot of cost. For
example, if you're willing to put up with some extra engine weight, or
some extra fuel burn, or whatever, you can get in the air lots cheaper.
The real costs come in getting the last bit of efficiency was his point.

Let's take some hypotheticals:
* An "aircraft style" two seater, 1600 pounds gross, 1100 empty, 160
knots, 9 GPH, 60 thousand bucks
* An "unoptimized" two seater, 2000 pounds gross, 1400 empty, 140 knots,
11 GPH, 30 thousand bucks

I know which we'd all like to have, but which we'd all like to pay for.
I think that one factor is that most of the auto engine planes look much
less than cool, with gunky cowls and radiators and such. If somebody did
a "cheapmobile" and it looked cool...

Ed Wischmeyer

What was that rumor about Toyota again?

--
----Because I can----
http://www.ernest.isa-geek.org/
------------------------