VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1912-1928 Aluminum piston in 1928 engine. (Need help)

I am going to install new piston (EGGE,with saw slot on the side)in a -28 engines.
In CHEVROLET Repair Manual Series AA-AB page 35, they says : Invar Strut pistons shuld be instaled in motor with the saw slot TOWARD the cam shaft.

In a Danish copy of the same manual they says: Invar Strut shuld be instaled in the motor with the saw slot TOWARD the carburator side. If you see the engines from the front and back. The cam shaft are on the left side, and the carburettor are on the right side.

I have some old pistons ( picture) and theey have a arrow on the top(forward) and the slot will be on the carburator side.

My englich are not the best,so my be I misunderstanding ?



If someone can tell me what is the correct installation ,or what I don't understand, it will be great.

Regards Arvid

http://www.chevroletnorge.com

Too bad I did not advise you on purchasing the EGGE pistons. Not recommended.

However, if you have already purchased them, they are to be installed as stamped on top of the piston. They should be marked (front) or an arrow or some other means. Key solution is all pistons facing the same way.

I would have recommended a 261 set of pistons.

Ray, Would that be a 1954 to 196? Chevrolet 261 truck engine piston for the 1928 AB engine? Would you be able to use standard pistons for most applications or maybe the oversize as needed? I have a nice set of 261 rings I picked up on eBay.

if so you could buy two sets and have enough for three 28 engines, that sounds good!

Hello RAY / MrMack
If the EGGE pistons was markeed with a arrow or some other mark on the top,it will not be a problem . But they have not any marks on the pistons top. The only marks are +.040 on the top, opposite side of the slot.

I have used several sett of pistons from EGGE some years ago, with no problem.(Chevrolet 1926 to1928(3set) 1929 (2 set) 1932 (one set) Willys Jeep 1944 (one set) and Harley Davidson 1919(one set)
and I believe they was arrow mark, but I don't remember

A Chevroletfriend of my says the slot must be the opposite side of the pressure side. But I don't understand what side the pressure side is.

Regards Arvid

http://www.chevroletnorge.com

The most side (thrust)pressure on a piston is on the outside of the rotational circle; which would be the intake side of the block on the power stroke.

Here is the EGGE contact web site, maybe they can help you. Good Luck.


http://www.egge.com/contact.shtml

Thank you 35 pickup man and Louis C. My be I understand it, and my be not.

When the power stroke begin,the pressure are only on the piston top? When the piston have moved down in the cylinder,the pressure will be on the cam side cylinder wall? I can't understand why the pressure will be on the intake side?

Louis. I have send a mail to EGGE.



Regards Arvid

http://www.chevroletnorge.com

I have 4 NOS 261 aluminum pistons 3 3/4" dia. If anybody needs them for a rebiuld.

The intake side of the cylinder takes the side trust from the combustion pressure that forces the piston down and to the outside of the circle of crankshaft rotation. The cam side force side thrust is from compression pressure and exhaust pressure both on the upstroke which are much less then the combustion pressure. All the work produced by the engine is on that combustion stroke. The crank stroke is trying to straighten the rod and piston outboard (the opposite of your sketch) to the driver (intake) side of the engine.

So the solid side of the piston skirt should go on the intake side??? Or is the purpose of the slit to relieve some of that pressure?

ray does the 261 pistons have the same pin size as the 28

The reason for the slot was to controll expansion.The slot actually weakens the piston skirt and thats why it is not placed on the "thrust" side of the piston.

The only modification to use the 261 piston is to enlarge the hole in the rod to accept the larger piston pin. For more excitement in the machine shop, bushings could be made for the piston and use the original pins.

OK. Her are the answer from EGGE:

Ask Bob @ Egge.com skrev:

> Standing in front of the car looking towards the engine the splits would go towards the right side. Sitting in the car the splits would go towards the left side of the car.
> Let us know if you need any other information.
> Thank you
> Egge Machine Co
>
> ----- Original Message ----- From: "Arvid Bjørnerud" <ar-b@bluezone.no>
> To: <askbob@egge.com>
> Sent: Sunday, March 19, 2006 1:30 PM
> Subject: Pistons for Chevrolet 1928

Regards Arvid :confused:

http://www.chevroletnorge.com

:confused: :confused: ??

Yep, that's Egge Machine! Their answers are almost as lousy as their pistons. :( :( :( :(

I'd just put the slot toward the cam and let the good times roll. Seems to me the pistons would provide the best service if you put the stronger side of the piston skirt on the side that will be forced to endure the strongest forces (the intake side according to 35 Pickup Man)...If that's a bad idea I'm sure one of these more knowledgeable fellows will let us know.

Tyler

I worked and retired from GM Powertrain as a Durability Engineer at GM Proving Grounds and all our Split skirt pistons were installed with the split on the compression side not the thrust side.

Maybe it is because I am a Texican, but it seems pretty darn clear to me toward the right if you are out front a'lookin' into the engine ,over the radiator the splits go toward the right, or iffin youall are a'sittin' in the seat of the car a'lookin' over the dash the splits go to the left.

JYD, I get the impression that you are a sorehead regardin' anything to do with EGGE!
Chill out and have a cool one! Thangs will look different when you are mellowed out!...Well maybe not....

well , by doggies Youall done got that leddle problem figured out. Now lets' jest sit back and watch and listen to Arvid to start a'bustin' some knuckles... I never heard anybody cuss in Norwaygian before!

Let'r Rip Arvid!

Hey Macky Wacky! Obviously you have not done much business with Egge or used their pistons and main bearings, or viewed some of the engines that they have "professionally" rebuilt in the past. Even in their local area they don't have a very good reputation. You must lead a sheltered life down there in good old Texas!

Yeah, that is true JYD, I was kinda sceered off of them by Yours Truly!

I may be Wacky but I ain't stupid!!!!!


Yakedy Yackey Yack!!!!

Cool! Glad to hear that the "Wacky One" has his act together from time to time.

I also got my longhorns in a row, I don't have any ducks, they all got drownded last weekend!
yours may have got drownd but mine were drownDED......

Did you ever get one of your old cars running good enough to get over the hump to Grand Junction, Doggie Doodle?