327 heads & SS valves,Robert

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327 heads & SS valves,Robert

Postby h-bot » Wed Mar 06, 2002 9:08 pm

From: pfjk36322_REMOVE_720029_THIS_@yahoo.com


I've got a set of 327 Vette heads that I want to
use on my Monza.Is the nickel content of these heads
going to allow me to run Stainless valves w/o pounding
the seats or tulipping the valves.The motor is not
for all out strip use or a daily driver,and I'll use
hi-octane for cruising.
My former bro-in-law used SS
valves in his 289/302 hi-po which he street drove for 8
yrs(hi-sch & tech sch & work),and has had no prob's dragging
the car for the last 4 yrs(measured installed
height/visual).I was wondering if this is just a blessing from
Ford(hi-nickel) or if this will work for any non-rad built
motor.
I really don't want to spend the $'s for hardened
seats(not to mention I don't trust any of these local
'bubba' machine shops to do the job right) if I really
don't need them for the future use of this
motor.
Also.thanks for the info on the fan.You understand that the
fan may also be pulling the rad toward it.Try a
strobe lite(timing light) and see if this is
ocurring.
Thanks,Frank


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327 heads & SS valves,Robert

Postby h-bot » Wed Mar 06, 2002 10:38 pm

From: voodoo_competition_REMOVE_274310_THIS_@yahoo.com


Frank,
I have heard the horror stories for
years of how unleaded fuel pounds out the seats, wears
out guides and everything else. In reality, I am yet
to see the accelerated wear that people claim.


Keep in mind I spent 2 years in a machine shop
doing nothing but rods and heads.

In almost
every instance of accelerated wear, I can trace the
problem to incorrect seat widths, r valve guide clearance
and/or valve stem seals that were 'too effective' at oil
control.

The amount of lubrication offered by the
miniscule lead content in fuel was negligible at best and
people give it more credit than was due.

Ask a
polymer chemist what role tetraethyl lead played in the
formulation of gasoline and he will tell you everything but
lubrication.

In 1990, I took a tour of the Union 76 Refinery
in Wilmington, California. I asked one of the
chemists there, in charge of quality control, why lead was
added to fuel. He told me this:

"Lead is a
combustion retarder. It raises the octane rating. Nothing
more. People claim it is for lubrication. That is
false. You should see the wear exhibited on some of our
pumps that are submerged in gasoline. I see the same
amount of wear now, with unleaded fuels, that we had
with leaded fuels."

My 429 Ford ran very high
spring pressures and had OEM seats, ground right into
the head. I cut exhaust seats to .080" in width and
intake seats to .060" both centered on the
valve.

I drove that car for 80,000 miles and made
countless dragstrip passes. When I sold it in 1998, I
disassembled the 429 SCJ and replaced it with a 460. I sold
the parts individually on E-Bay because I didn't want
anyone to end up with the complete motor.

That
11.25:1 429 made 430 horsepower at the rear wheels and
killed the C6 Automatics with regularity. The 4400 pound
car ran 13.80 @ 106 all night long and would do it at
100° or 75° temperature. It made no difference
whatsoever.

The heads looked so good when I removed them you
would not believe it. The seats were still very narrow
and the guides were still tight.

I think
your heads will be just fine. One thing to keep in
mind is valve stem seals. On a Chevrolet, all I ever
use is the stock 'O' Ring seal. I have never had an
oil control problem if the guides are sound.


The only other seal I would use would be the very
small 302 Ford Umbrella, but I don't like them as well
as the 'O'Ring.

People can use what they
want, but for longevity, I think Teflon Seals are too
good and deprive the stems of necessary
lubrication.

Make sure your seat widths are narrow and well
centered on the valve. You will enjoy many thousands of
miles from them with no troubles.

Also, with
respect to 'pounding' of the valve seats. I have only
seen this a few times and in each of these cases, I
noted weak valve springs and high rpms that caused the
valves to 'bounce' off their seats.

Be sure you
have the correct springs for your camshaft and always
less than 300 lbs. open pressure on a flat-tappet
street engine.

I hope this information is
helpful...Robert


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327 heads & SS valves,Robert

Postby h-bot » Wed Mar 06, 2002 10:46 pm

From: voodoo_competition_REMOVE_683915_THIS_@yahoo.com


Another thing to keep in mind when comparing the
Ford to the Chevrolet is the placement of the exhaust
valves.

GM put the two center exhaust valves together on
the small block. This is a bad design from any
engineering standpoint. Adding a heat crossover in this area
just makes it worse.

Ford (Except 272/292/312)
staggered the valves so the exhausts were never immediately
adjacent to each other. This makes more sense and I have
always had better longevity on a Ford head for this
reason.

This is not to say the Chevrolet heads fall
apart, it is just the observation of the different
engineering style.

Most of the bad seats & valves I
see on a small block Chevrolet are the two exhaust
valves in the middle of the head. I run these guides a
little on the loose side for this reason.

I
still think your 327 heads will last you just fine. All
the ones I have been doing are holding up very, very
well. A few weeks ago I shipped a pair of 461's to
Australia. This fellow is a repeat customer and he has about
45,000 kM on a set of my heads.

Be sure to force
a good quality oil into the guides during assembly.
I squirt some in the guide, cap one end with my
finger and force the valve in until oil spurts out
around the valve.

Often I will mix up a mild
molybdenum paste with the oil and force this into the guides
also.

Details make a difference...Robert


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327 heads & SS valves,Robert

Postby h-bot » Thu Mar 07, 2002 6:04 am

From: erik_norway_REMOVE_422538_THIS_@yahoo.com


Hey Robert.

I can only agree with you I
put together a 1969 model Volvo B20 motor a few years
ago and put this in a Volvo 142.

The engine
was slightly tuned putting out 130-140hp (Stock
85hp.

Everyne told me I would pound the heads and valvess
running unleaded.

But now 60.000km+ later it still
runs greate and thats afther a lot of abuse.

I
have sevral friends who have done the same and hade no
trouble.

So you heads will be just fine.

Btw I used a
Mirra on the head and valves.

Erik
Oslo in
Norway


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327 heads & SS valves,Robert

Postby h-bot » Thu Mar 07, 2002 7:05 pm

From: pfjk36322_REMOVE_913665_THIS_@yahoo.com


Thanx,Robert.Heard some of the same things.Second opinions' apply outside of the medical field,too.
Frank
Just hope this hasn't opened up yet another can of worms.LOL


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