<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Joaco:
<B>I already have a 911 fan and shroud, that came with the used type 4 2.0 l engine I bought.
</B><HR></BLOCKQUOTE>
Hey I'm in the market for a 911 style shroud, email me if you wan to sell it
best type4 into type1 shroud ?
-
micah
best type4 into type1 shroud ?
In the research I've done,the DTM seems best.First,it looks outrageous!,but also finely engineered.Cali's set up seems less than ideal because you have to (I think) use a cheesey Taiwanese 36hp dog house shroud,and I hate that crap!!And then the Porsche style set up would kill a poor slob like me.OPP offers the the best compromise.Also,I'm only building a 2165cc(94x78mm) with a moderate cam ,modified dual Kadron-Solexes,mild head work and electronic ignition.Perfect for me.
-
Joseph
- Posts: 593
- Joined: Sat Jul 01, 2000 12:01 am
best type4 into type1 shroud ?
Doug,
I would'nt worry about the Alternator
charge. Even if you reduced the Alternator to
half speed (which you would not do) it would
still charge as good as a generator.
What fan and what ratio is very difficult
to prejudge. It would require your testing
the temp and noting the difference as you
make the changes. Your engine will be unique
and I have not seen any reliable temp
figures so play it safe and do your own
Checking.
Just monitor that engine as you go along
and you will know as much as anyone else
what the effects of each changes will do.
So far, a well placed 1440CFM (Type 1)fan
will cool a 2270 within the mid 300F range
and hold the oil temp at 200F (with a remote
oil cooler and a cooler in the engine's fan airstream.) To determine the fan's 1:1 ratio output, Multiply the inverse of the factory ratio times the given CFM output at the factory ratio. Knowing that starting point will allow you to "design" the crank size and know where you're going CFM wise
as you change pulley sizes.
Joe
Oregon Performance Products http://www.spiretech.com/~opshroud
I would'nt worry about the Alternator
charge. Even if you reduced the Alternator to
half speed (which you would not do) it would
still charge as good as a generator.
What fan and what ratio is very difficult
to prejudge. It would require your testing
the temp and noting the difference as you
make the changes. Your engine will be unique
and I have not seen any reliable temp
figures so play it safe and do your own
Checking.
Just monitor that engine as you go along
and you will know as much as anyone else
what the effects of each changes will do.
So far, a well placed 1440CFM (Type 1)fan
will cool a 2270 within the mid 300F range
and hold the oil temp at 200F (with a remote
oil cooler and a cooler in the engine's fan airstream.) To determine the fan's 1:1 ratio output, Multiply the inverse of the factory ratio times the given CFM output at the factory ratio. Knowing that starting point will allow you to "design" the crank size and know where you're going CFM wise
as you change pulley sizes.
Joe
Oregon Performance Products http://www.spiretech.com/~opshroud
-
steve stromberg
- Posts: 142
- Joined: Fri Oct 13, 2000 12:01 am
best type4 into type1 shroud ?
I picked up a 914 for parts I got 2 extra engines one has a fiberglass shroud sort of a horseshoe shape with Type1 alternator in the center the guy said he got it from Euro-race.? anyone know how these work?
-
Joseph
- Posts: 593
- Joined: Sat Jul 01, 2000 12:01 am
best type4 into type1 shroud ?
Steve,
The center mounted fiberglass shroud was a
product of German Auto. Eurorace had what is
essentially a Cali design except the cylinder
covers were fiberglass and the shroud was an
aftermarket 36HP with a doghouse. They called
it a "Carrera" Hmmmmm. That kit is no longer
marketed and was sold to MSHP. Can't tell
you where or who's planning on selling it again.
I don't hear much about the German Auto shroud except that a copy of it is/was being sold in the UK. Fat originally marketed a T-1
center mount shroud for a Type 4. I don't
hear much of that product. Center mount
shrouds for Type 1 engines are still sold.
Mounting a radial fan in the center of a
shroud to give the appearance of a "911" or
because it will distribute the air "more
evenly" throws a few physical laws down the
toilet.
Air leaving a radial fan moves outward AND
in the direction of the fan's rotation thus
scribing an arc. Since the fan is turning
clockwise, the arc is curved to the right.
At the top of the fan the air is going
outward and to the right. On the right side
of the fan the air is going outward and down.
on the bottom it arcs to the left and on the
left side it arcs upward.
That makes the right side of a flat engine
a great target for the fan's air. The left
side suffers because the air is going the
other way (up)so air guides are installed to
turn the air around. Its a well known fact that air does'nt like quick turns so the
greatest distance is made in the shroud to
permit the air to turn as easy as possible.
Thats done by moving the fan to the right
of center on the shroud.
The result is a lot like taking the kink out of an exhaust pipe. In the VW design, they
picked up a perfect spot for a single carb
and the best possible air flow to #3 and #4
cylinders. Thats not the case with the centermount, a CHT tells all.
Joe (of the West)
The center mounted fiberglass shroud was a
product of German Auto. Eurorace had what is
essentially a Cali design except the cylinder
covers were fiberglass and the shroud was an
aftermarket 36HP with a doghouse. They called
it a "Carrera" Hmmmmm. That kit is no longer
marketed and was sold to MSHP. Can't tell
you where or who's planning on selling it again.
I don't hear much about the German Auto shroud except that a copy of it is/was being sold in the UK. Fat originally marketed a T-1
center mount shroud for a Type 4. I don't
hear much of that product. Center mount
shrouds for Type 1 engines are still sold.
Mounting a radial fan in the center of a
shroud to give the appearance of a "911" or
because it will distribute the air "more
evenly" throws a few physical laws down the
toilet.
Air leaving a radial fan moves outward AND
in the direction of the fan's rotation thus
scribing an arc. Since the fan is turning
clockwise, the arc is curved to the right.
At the top of the fan the air is going
outward and to the right. On the right side
of the fan the air is going outward and down.
on the bottom it arcs to the left and on the
left side it arcs upward.
That makes the right side of a flat engine
a great target for the fan's air. The left
side suffers because the air is going the
other way (up)so air guides are installed to
turn the air around. Its a well known fact that air does'nt like quick turns so the
greatest distance is made in the shroud to
permit the air to turn as easy as possible.
Thats done by moving the fan to the right
of center on the shroud.
The result is a lot like taking the kink out of an exhaust pipe. In the VW design, they
picked up a perfect spot for a single carb
and the best possible air flow to #3 and #4
cylinders. Thats not the case with the centermount, a CHT tells all.
Joe (of the West)