The Quarky Engineer

I measured the bores on the Perrin EZ30R motor, as well as the pistons. This is a sleeved block with Darton sleeves.

There are some flaws with my technique…. I do not have a torque plate, so the bores will certainly distort after the head is installed. The factory bore size if 3.512″, and the size of the pistons new from Supertech is ~3.5085″, which would be a clearance of 3.5 thousandths.

These bores are all slightly bigger, averaging around 3.5138″. While there certainly was some wear, it would appear it was originally setup with larger PWCs. I’m not that concerned about the 5.5 thousandths PWC, as it is a race motor. I’m not looking for quiet.

I will probably get the pistons coated, which depending on the coating can add 1 thousandth.

Comments?

Does anyone happen to know the dimensions of the FA20 head studs/bolts? They are an 11mmx1.25 thread, but I am curious to know the length as compared to EJ head studs.

I am rebuilding the original Perrin EZ30 Gen 2 motor, and when it was build the block was tapped to accept 11mmx1.25 head studs. (Factory is 10.5mm). Since Jeff didn’t have time to get custom studs made, he used ARP EJ head studs with a spacer. I’d like to find another ARP 11mm stud that is shorter.

ARP does now make 10.5mm EZ30 Gen 2 head studs (sold by Outfront), but this block has already been modified for the 11mm size.

In the picture attached, you can see the factory EJ, ARP EJ, the Perrin modified ARPs, the factory EZ Gen 2, and an ARP EZ Gen 1 (which must have been custom since they are not in the catalog).

If you look at the catalog picture of the FA20 ARP studs, they don’t have the extended tip, and look to be a tad shorter.

(Jr Junior Barrios, Clark Turner, Jeff Perrin,Mike McGinnis, Timothy Bailey?)

I was nominated by my friend Tom Floyd to post one picture of my car- only one photo! In addition, I need some people that I think are great car friends to join the challenge to keep this running. Let’s flood Facebook with car pictures.

My SGI Indy came today. Christopher Neil Bradley and Clay Cowgill will recognize the source. I went looking for a SCSI CDROM drive to install an image from and found an old box. Inside the box were some old goodies of both older and newer vintage than the Indy.

Anyone have an Exabyte drive laying around? I would love to restore that backup tape from 1992. (College)

Yes, that is a 3DFX card. Old school awesome.

I have inspected the Supertech 89.2mm pistons that came out of the Perrin EZ30R motor, and they are in great condition. Measurements are right on, and skirt wear is minimal. They had pretty significant carbon deposits, so I cleaned them in an ultrasonic cleaner. I now have the bare pistons, and would like to get them coated. When they came from Supertech, they had a phosphate dry lubricant coating, but that coating is mostly gone now after the cleaning.

Any recommendations for a place near by (Portland) that can do replacement coatings? Any issue coating a used piston? Does it have to be media blasted?

Anyone else have any other Intel April Fools Day press releases? Christopher Neil Bradley? This one is from 1998.

Yukon did well in the snow. Cooper Discoverer Studded, no chains needed. (but I do have them with me).

Now this is awesome! 13-14 inches everywhere!

I picked up a couple more Mitutoyo tools. The small micrometer, and a regular caliper to replace my cheap one. I have typically used the micrometer ones because they are good to +/- 5/100,000ths of an inch [1.3 microns]. The regular caliper is only spec’d to .0010 (1/1,000ths of an inch), although the calibration sheet shows an error of only 0.0005″.

The spec sheet for the caliper shows at 2 inches an error of +0.0005, and the spec sheet for the 2 inch gauge block shows an error of 0, and when I measure the block with the caliper it reads 2.0005. I love it when stuff adds up!

Now I’m just walking around measuring stuff.

Nice start to 2017!