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Re: 1962 Panel Van Engine Rebuild
Posted by: MattNall ()
Date: April 16, 2018 11:03AM

That's the least of concerns..if cam measured good.





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
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Re: 1962 Panel Van Engine Rebuild
Posted by: JimBrandberg ()
Date: April 17, 2018 04:52AM

<<>>

When concerned in the past I've used a pair of solid lifters as a test before assembling which doesn't help your situation.
There was a thread recently about filling lifters before using. I haven't been doing that but may start the practice.

Yesterday I was doing the opposite, bleeding lifters down with a 5/16 bolt in the vise. They were new old lifters where 8 out of 10 would not compress pushing on them by hand. They must have been filled at the factory. Slow to compress, about 1/16 turn on the vise every few minutes. I don't know how I ended up with 10 lifters, I have a few 4s left over from buying 16.
I think I'll practice filling them as long as I'm at it.

Hopefully someone else with more lifter knowledge will add something.

Jim Brandberg
Isanti, MN
CorvairRepair.com

Re: 1962 Panel Van Engine Rebuild
Posted by: Nick_Soapdish ()
Date: April 18, 2018 09:35AM

JimBrandberg Wrote:
-------------------------------------------------------
> The biggest
> factor in your pushrod geometry will be your
> camshaft base circle, maybe compare the Isky to
> the stock cam before installing to help form a
> hypothesis.

The Isky is indeed smaller, by about .090 (not exact). With .010 shaved off of the heads and stock gaskets, that would results in the pushrods sitting effectively .035 or 1/32" shorter than stock.


JimBrandberg Wrote:
-------------------------------------------------------
> Sometimes I think I ramble on too much

You'll get no complaints from me. I seriously appreciate all of the input and information.

Re: 1962 Panel Van Engine Rebuild
Posted by: JimBrandberg ()
Date: April 19, 2018 05:03AM

I'm okay with your math .090 divided by 2 minus .010. I hope it works out in real life when spending for 12 pushrods, there is an adjustable one for measuring but probably not cost efficient for one time use.

Jim Brandberg
Isanti, MN
CorvairRepair.com

Re: 1962 Panel Van Engine Rebuild
Posted by: Nick_Soapdish ()
Date: May 15, 2018 09:06PM

Another dumb question: the piston deck clearance with standard (.010) cylinder base gasket is 0". The measurement is uncompressed, so includes the ~.007 "bump" in the gasket. What thickness of base gasket would be recommended to get proper deck clearance.

Dylan
'62 95 Panel
Seattle, WA

Wagons and vans, just clap your hands.

Re: 1962 Panel Van Engine Rebuild
Posted by: JimBrandberg ()
Date: May 16, 2018 05:14AM

With bored cylinders that have no ridge on top, I don't know if there's a proper deck height, it's more a value to plug in to the compression ratio calculation. Of course that's within reason, you probably don't want pistons protruding or recessed 1/16".
I usually get about .010 deck height. I hold the cylinders down with 2 tubes cut to length and head nuts. I have a tool with a straight edge and dial indicator but would probably use a straight edge and feeler gauge if I didn't. The dial indicator is nifty because you can make sure you're reading the minimum value.
I don't factor in the little ridge on stock base gaskets when figuring.

The piston to squish area in the head clearance can be critical. With stock parts, it's not usually a danger but it's something to think about with your 64 cylinder and 63 head scenario. I hate to just talk off the top my head but .090 minimum comes to mind and that's probably more for a race engine trying to get maximum C/R.

A nice squish is a good thing for preventing detonation.

Have you figured your compression ratio using zero as a deck height? There was a fellow on the other thread running the numbers.

I may not be thinking clearly about an engine not in my presence and would like to read what others have to say about your question of proper deck clearance.
The scenario of using 63 low compression heads on a 64 engine and having it come out with a suitable compression ratio seems too good to be true, why isn't everyone doing it with heads getting scarce? But on your other thread, the numbers seemed to be working out. It just make me a little nervous.

Jim Brandberg
Isanti, MN
CorvairRepair.com

Re: 1962 Panel Van Engine Rebuild
Posted by: Nick_Soapdish ()
Date: May 16, 2018 08:13AM

JimBrandberg Wrote:
-------------------------------------------------------
> I don't factor in the little ridge on stock base
> gaskets when figuring.
>
> The piston to squish area in the head clearance
> can be critical. ... .090 minimum
> comes to mind
>
> Have you figured your compression ratio using
> zero as a deck height?
>

The heads have about .070 step. With .032 head gasket that should result in decent squish clearance, but I would be more comfortable with .010+ deck clearance added.

C/R with 0 deck would be around 8.94:1, vs. 8.73:1 with .010. Could stand to lose a bit off of the latter figure.

The other question: can standard steel base gaskets be "stacked?" If so that's looking like the easiest (and cheapest) solution at this point.

Dylan
'62 95 Panel
Seattle, WA

Wagons and vans, just clap your hands.

Re: 1962 Panel Van Engine Rebuild
Posted by: JimBrandberg ()
Date: May 16, 2018 08:28AM

I would be inclined to use copper base gaskets rather than stacking the stock ones if a thicker base is what you want.
8.94/1 with a good squish may be less prone to ping than 8.73/1 and not a good squish.
I wish someone else would weigh in here, especially with an opinion on what piston to head dimension is considered a good squish.
I like using stock steel head gaskets instead of copper when possible so I like the idea that you're adjusting the base if something is necessary.

Jim Brandberg
Isanti, MN
CorvairRepair.com

Re: 1962 Panel Van Engine Rebuild
Posted by: MattNall ()
Date: May 16, 2018 08:30AM

Jim, written here many tomes... 0.040" is optimum .

Racers seem to want a little more due to the high rpm they run.





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

Re: 1962 Panel Van Engine Rebuild
Posted by: Brizo ()
Date: May 16, 2018 09:28PM

Nick, I prefer to stack only the steel head or base gaskets simply because I feel they're harder and more stable than the softer copper. I recently built a .060 over 140 with a .250 stroked crank using stock rods. Due to several factors, I stacked 5 base gaskets, 2 head gaskets, and cut back 15 CC's of aluminum from the step to yield a 10:25 CR and .047 squish area. I've stacked steel gaskets several times over the years for different reasons. Make sure to stack the base gaskets "ridge up" and I coat them with High-Tack.

Dan Brizendine,
'64 8door Greenbrier 140 PG. "In beautiful Wanamaker Indiana...with one stop light and 5 pizza shops"

Re: 1962 Panel Van Engine Rebuild
Posted by: JimBrandberg ()
Date: May 20, 2018 06:01AM

I would defer to Brizo about stacking steel base gaskets, if it works for him that's good enough for me.

Is "Gasgacinch" considered High-Tack?

Jim Brandberg
Isanti, MN
CorvairRepair.com

Re: 1962 Panel Van Engine Rebuild
Posted by: Nick_Soapdish ()
Date: June 06, 2018 04:13PM

Got a new stupid question! The head gaskets I'm using have a short section of ridges cut into the cylinder-side surface. Does it matter which direction they are oriented?


Re: 1962 Panel Van Engine Rebuild
Posted by: Nick_Soapdish ()
Date: June 06, 2018 05:05PM

*head side

Re: 1962 Panel Van Engine Rebuild
Posted by: MattNall ()
Date: June 06, 2018 05:52PM

Correct!





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

Re: 1962 Panel Van Engine Rebuild
Posted by: Nick_Soapdish ()
Date: June 06, 2018 06:05PM

MattNall Wrote:
-------------------------------------------------------
> Correct!


Thanks!
The question I have is whether the notched section has a correct location (o'clock position if you will) along the perimeter of the combustion chamber. I.E. should it be pointing up, down, front, back, in the engine?

Re: 1962 Panel Van Engine Rebuild
Posted by: MattNall ()
Date: June 06, 2018 06:17PM

Just the crimp is UP... nothing else matters as long as it not too small [ 60-64 barrels / heads





MODERATOR
Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!
..............................110-PG.................................................Webered-Turbo

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