Technical Chevy 235 Pistons overbore

The hop up of my inliner stopped.
Found a 15" crack in one engine and the other is worn out so that Pistons with 0.08 over wont be enough. I read that it is possible to bore thi engine to 0.10 over without Problems. Is this right?
But where to get Pistons and Rings? Does anyone knows where to get them?
In Germany i could get custom made ones, but for that money i can rebuild a Rolls Royce.
Sleaves is the last option but the job is in germany also expensiv.

 

Egge Machine Company shows them. 332 dollars a set. They show over size to .125 ! Not sure if thats a good idea,but the .100 should be fine if it can go that far over.

 

@irishsteve
Egge only has pistons, but no rings

 

Northern Auto Parts lists their kits, but pistons only go to .o60. The kits are pretty complete.

 

Have you sonic checked the wall thickness to see if 0.100 overbore will be ok?

 

A ford 272 is about .060 larger than a 235 and I think the ring widths are the same by ordering the right oversize they should file fit.

 

When i sonic the wall thickness. How much do I need?
I mean, how thick must the wall be after boring?

 

The Ford Y-block uses a floating pin with wire retainers, but that is not really the problem. The 235 uses a clamped pin with a connecting rod which is slit on the small end. The wrist pin on a 235 is much smaller in diameter (.866") than the 272's .912" diameter and would require boring out the small end of the connecting rod nearly .060". Enlarging the small end bore of the rod that much may leave it a little thin. It's not a really strong rod to begin with. Using a 261 rod maybe a better choice. All the dimensions are the same as the 235 except the pin size (.927"), and it is a much stronger rod over-all. It would require enlarging the pin bore in the piston .015" and using the 261 pin. Without doing a bunch of research, it don't know if the pin would have to be shorted to 272 length or not.

 

I was talking rings only, he said EGGE had pistons to .125 over but no rings.

 

Sleeve it!!!!!

Egge will either have rings for thier pistons or know where to get them. They probably build their pistons to accept a common modern ring. That is why one must sometimes pick up a telephone. What a concept.

No offense intended. Just sometimes we forget two things one is that yes international calling can be pricey (maybe one of us would be kind enough to make the call and relay the information) and calling on the phone and talking to a real person has supported our industry for well over 70 years. One may even call it traditional.

Anyway like I said phone call is in order and maybe one of us would be willing to make the call.

Or just sleeve it.

 

A good standard minimum .100 on the thrust side

 

When you say “worn out” has that engine been taken apart and the bores mic’ed?
I only ask this because I foolishly gave away an engine that I was told needed a rebuild. It was in a pickup I bought and when I pulled the heads the pistons were stamped .030.

I wasn’t hip to having it bored larger. The guy who I gave it to tore it apart and found several pistons that had stuck rings and near no taper in the bores.
He brush honed it and a fresh set of rings and ran it.

Most times “okay” is good enough.

 

You are correct sunbeam, I misunderstood the question.

 

Thanks for your arnsweres.
Yes i mailed egge and he would help me to find pistonrings that will fit. But in the meantime i got a better block that can be rebuild with 030 overbore, so i don´t need to sonic it and may have enough "meat".
But now ther is another problem. I got in germany pistons from silv o lite . But they have no oil bores for the wristpin( piston pin) . Are they not necessary? Or is it a good idiea to drill them?

 

Thanks you are right, but it is not only expensiv to call to the USA it is for me even difficult to undrestand the spoken word. The written comends are sometimes difficult enough.

 

Sivolite shows the same piston for a 235 from 1952 - 62 a 1413 Listed as press fit because the pin does not float in the rod. I would not be concerned about the oil holes

 

Here is the next Question for 235 specialists.
The stock pistons has an subordinate ( hope you understand) from 0,4mm. The new pistons have a shorter compression hight. So there will be at top dead center 1mm to the top of the block.
would you mill the whole 1mm?
I plan to mill the head also 1,5 mm.
The new headguescet messures 1,7mm uncompressed.

 

What you are talking about is zero decking so the piston is right at top of the cylinder. That's usually good for quench. It will probably help you with surfacing the head to reduce chamber volume a little, with corresponding increased compression.

 

I guess back in the day they really milled those heads to the maximum. Ive seen pictures from years back where the area around the valves was very small.

 

Hello Motoriac, we do have a set in stock for # L2037-6. in +..030" (complete w/rings) if you are still in need. More tech info here: https://egge.com/product/egge-piston-set-with-pins-145/ for you.

 

I have milled the deck of a 261 block .060 ,1.5 mm ,with no problem...But most most gaskets are close to .060 thick so the quench/squish is still not close to enough to be effective...You might find some .040 gaskets or Cometic gasket to make one for a price.

 

Egge machine2 ,

Good to see a representative on here now .
Many guys on here recommend your products ,,,,,including myself .
Some people only want the most expensive that can be purchased,,,,,,,my feelings are why waste money .
Egge has a quality American made product ,,,,,,more than good enough for 99 % of the hot rods running around .
Most machines now will not see a few hundred miles a year,,or maybe a thousand miles ,,,or even super high rpm .
They should last forever ,,,or at least our lifetimes,,,LoL.
Thank you for speaking up .

Tommy

 

@Desoto291Hemi , glad to be of service and part of this great community!