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cylinders, pistons, rings, and rods
Posted by: bought1 ()
Date: January 08, 2019 12:12PM

So I have this 140 hp engine sitting in the corner of my garage and it is the wrong time of the year to wrap up the body work on my project car. So, I am toying with rebuilding the engine to keep the project moving forward. Previously, I had bought a 280 cam and new lifters, and now I am thinking about cylinders, pistons, rings, and rods. Since Clark's is "local" to me, I am thinking about buying one of their "kits" and have them install rods on them. I think I will be going to full finned cylinder since they are not that much more.

Questions I have are:

Since I am upgrading the cam to a 280, should I go bigger with the pistons...0.40 or .60 over? Also, what do folks think about Clarks' premium cast pistons or would forged be better?

What type of rings would you recommend: cast chrome, something else.

Do the valve springs need to be upgraded?

Keep in mind the car will be driven in a spirited way, but not raced.

Thanks!

Dave

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Re: cylinders, pistons, rings, and rods
Posted by: davemotohead ()
Date: January 08, 2019 01:07PM

I would go .060 Forged pistons with Molly rings (Not Chrome) and Clarks full fin cylinders, Isky springs on the heads for less coil bind from the 280 cam, BUT if you are going to have Clark's install ARP rod bolts insist on the original ARP 12 sided nut, for some reason Clarks ARP rod bolts have another NON ARP Nut, this what just a big topic on the COG page and others chimed in saying the nut on their rod bolts is not correct? I tend to agree.





Email me at: Dave Motohead

1960 4dr sedan caveman car
1961 Rampside (Chetside)
1962 Rampside (Barnside)
1962 Short Rampside (Shortside)
1962 Monza 700 Wagon
1963 Monza 900 coup (General Nader)

-----------------------------------
Rust Free Lancaster Ca

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Re: cylinders, pistons, rings, and rods
Posted by: bought1 ()
Date: January 08, 2019 01:52PM

These Isky Springs?? [mikescorvairparts.com]

Dave

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Re: cylinders, pistons, rings, and rods
Posted by: Vairismo ()
Date: January 08, 2019 02:24PM

I am of the opinion that using the least valve spring that will get it to operate properly is the best course. YMMV

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Re: cylinders, pistons, rings, and rods
Posted by: hardcase ()
Date: January 08, 2019 03:30PM

I got a set of rods with the non-ARP nuts, like Dave described. Also, when Clark's rebuilt the rods, they had only tightened down the nuts to 25 lb-ft, which is low. It probably had no effect on the big end diameter (several plasti-gages gave the same .0015" clearance), but they also recommend that torque for the final assembly.

That will not put enough preload (this may not be the right word) on the ARP bolts. So, I replaced the nuts that Clark's provided with the correct 12-sided ARP nuts and tightened them to the correct 32 lb-ft using ARP's lubricant.

I do recommend having Clark's install the pistons. I used their cast piston with a 0.030" bore full finned cylinder and chrome rings, just to be on the safe side, in terms of wall thickness. Those cylinders are supposed to be thicker than stock, so a 0.060" over would probably end up giving a cylinder wall thickness close to stock.

I went with an Otto 020 cam. The valve springs are whatever Tom Knoblauch is installing in his big valve heads.

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Re: cylinders, pistons, rings, and rods
Posted by: texas yenko dude ()
Date: January 09, 2019 05:01AM

yes




bought1 Wrote:
-------------------------------------------------------
> These Isky Springs??
> [mikescorvairparts.com]
> e-spring-isky-hi-performance-set-12-new/

Texas YENKO Dude
YS-070
YS-199
YS-320
Southeast of Disorder


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