Diamond Piston bore availability

[ALLTRBO]

Would it be possible to get Diamond Pistons for the 3400 made .100" over? If so, how much extra $$$?

[pocket-rocket]

We used to have a chart that showed safe specs for engine bores, and I believe that .060 was the most you want to go and still be in the safe bore wall thickness range in the 60v6 family.

[2.8-350TBI]

Under .060 or bust
Literally.
Unless you send your block off for hardening, but thats a different story.

[pocket-rocket]

Under .060 or bust

That made me lol.

[ALLTRBO]

The engine would only be about .020 over, I just want .100 over 3400 pistons.
<<< Not a newb engine builder.

[sprucegagt]

The engine would only be about .020 over, I just want .100 over 3400 pistons.
<<< Not a newb engine builder.

Last I knew, 35.. I mean .100 over 3400 Diamond pistons were not available.

[2.8-350TBI]

3500 block???

[ALLTRBO]

Yep, 3500 block, but 3100/3400 compression height so not 3500 pistons, just 3400 pistons .100 over.
I know it's a longshot, but if I don't ask then I'll never know.

[pocket-rocket]

That's what I was thinking. Might not even be a GM engine for all we know.

EDIT: Ninja'd FTL!

This going in your lawn mower in your sig? J/k That pic has always cracked me up, lol.

[ALLTRBO]

I do ride a Kawasaki Ninja, afterall.

Yes it's for the mower, I decided that the 8hp engine just wasn't cutting it.

[SappySE107]

I know its possible and I don't think that bore size will increase costs but I will find out for sure.

[blackbombshell95]

Before you bore out your cylinders you want to pay for a sonic check to see how far safely you can bore out the cylinders. Every block is different, some 3400's might take .030 more and some might take .050 more. But I see you have a 3500 block and I have no idea how thick the cylinders walls are.

I had my 3400 block sonic checked and I safely able to bore it .030 over. Some areas were super thick and other areas weren't.

U can see on Cylinder #1 I have a real thin spot and If I bored it .100 over it would be dangerously thin. Good luck with whatever you decide to do.

[ALLTRBO]

I know its possible and I don't think that bore size will increase costs but I will find out for sure.

Great, thanks!


Blackbombshell95, that's a good idea, though I'm pretty sure .020" over (.02126" actually) won't be a problem on a 3500 block. The bore is already 2mm larger than a 3400 (94mm vs. 92mm)
Thanks for the information on your block, cool to know!

[SappySE107]

They are available and there is no price difference for that bore size.

[ALLTRBO]

That completely kicks arse, thanks for finding out. I should be ordering some within the year, a lot sooner if the current used shortblock ends up with problems once it's fired.

Anyone want to buy a twin-turbo 350 6-speed '90 IROC-Z? It only needs a 'little' (read: a lot) of work! When I'm done with my 60V6 Fiero, my TT V8 won't know what hit it.