The new "spiroloc" wrist pin retainers as driving me insane!

I got the KB pistons from EMW and they come with the new fancy spirolocs for wrist pin retainers.

I just want some feedback about who thinks these are better than the plain old circlip retainer clips that come as stock.

IMO the older rings are MUCH easier to install and remove than the spirolocs.

I have spent an hour and many searches on the internet & youtube watching the spiroloc install but I still do not see how it can be done with the piston/cylinder up in the engine assembly.

AND I am planning ahead. Once I assemble everything & measure my deck height, I am expecting to have to take all of the pistons off.
Removing those spiroloc retainers looks like I will have caught turret's syndrome and ordered explosive devices online before removing just four of them.

What am I missing?!?

Stu

If you are assembling to measure, why put them in?

They are only there to keep the piston pin from galling the cylinder wall in operation.

Ok, so we used teflon buttons instead in our race motors.

They are not hard once you get used to them.

Pull them a bit to stretch them out. Lube them up with engine oil. Get an end started and twist them in by hand until you cant any more. Then twist them more with a pair of pliers. To get the last bit in, use a small flat head screwdriver and push the last tab in.

Getting them out can be fiddly. I use a jewlers flathead screwdriver to pry out the first bit, and then grab with pliers and work them the rest of the way out. Once you have the first third out, they get easier.

I'm not sure why these are used instead of the more usual circlips, but there must be a reason.

They stay in better. You wouldn't believe the damage one of the wire retainers does if it comes loose. I've use the teflon buttons on the street, no problem, for about 30K miles. Not recommended, but it worked fine for me.

IIRC I did the two spiral locks that are next to each other .... while they are off the motor. These leaves you with only 4 of the spiral locks to imstall once the pistons are on the motor.

Thanks for the hints.



I was only testing to make sure I knew how to remove them when the time came.
I can measure deck height without installing the last 4 clips.

Maybe I am too shy about stretching it out like a slinky.
I have pulled the spring until it is about 1" long, but it is still hard to get started into the hole.
Do you stretch them longer than that?

Stu

They pretty much covered it. I've found that the locks on the KBs go in easier if you align the first end away from the piston top/crown. That way the tall 'wall' will help guide the spiraloc into place.

BTW, DO NOT allow that engine to ping/detonate.

Care to elaborate?
I plan on running 9.5:1 at ~5600 ft. altitude (colorado) with 110 race gas.
Dual 40 Webers and JR race cam.

I know at least one team that has run the AA pistons at 13:1 for years.
Are the KB pistons that much more delicate?

Stu

I stretch them about 3 inches. It makes the diameter smaller which aids the first half of installation. Then use a small screw driver to push the rest in. I use a small straight jewelers screwdriver like said before to lift up the notched end, then grab it with a small needle nose. They will pull out with a screwing motion easily.

First comment, there are a LOT of KB engines out there that run great and have no problems. Keep that in mind.

Okay, now that the perspective is set up - KBs don't handle pinging. I know of two KB equipped engines that blew up. I've heard from other Type IV gurus who have had the same experience. I heard the same thing from a local V8 builder whom I respect immensely. Make sure you have a wideband O2 sensor on it, and you'll be aware immediately if it's running lean.

Why?
100 unleaded would work fine, and make more power.