340 Engine Rebuild
- Thread starter Sure Shot
- Start date
TA Performance has the high and low compression pistons for the 300/340.
Thanks.
I see the TA pistons, but they don't list the compression ratio for the 300/340.
In fact, they don't have much details listed
http://taperformance.com/products.asp?cat=196
Rockauto.com has some low compression pistons listed, with all dimensions, for 2bbl builds.
https://www.rockauto.com/en/moreinfo.php?pk=209216&cc=1493514
In fact, they don't have much details listed
if you've got a cell phone, it doesn't cost anything to call them and ask for specs.
480-922-6807
if you don't have a cell, emails are also typically free
TAPerf@aol.com
if you've got a cell phone, it doesn't cost anything to call them and ask for specs.
480-922-6807
if you don't have a cell, emails are also typically free
TAPerf@aol.com
In fact, they don't have much details listed
if you've got a cell phone, it doesn't cost anything to call them and ask for specs.
480-922-6807
if you don't have a cell, emails are also typically free
TAPerf@aol.com
the alternative is to talk directly to a piston manufacturer, a lot of times they'll have an old pattern on file and be able to make it. do you want stock type high comp replacement, hyper or forged?
the other alternative is that they might be able to point you at substitute piston that is similar to or just slightly larger than your stock bore which you can use in place of what you have. you might could wind up running a metric motorcycle piston with one of those ultra thin ring packs.
if you've got a cell phone, it doesn't cost anything to call them and ask for specs.
480-922-6807
if you don't have a cell, emails are also typically free
TAPerf@aol.com
the alternative is to talk directly to a piston manufacturer, a lot of times they'll have an old pattern on file and be able to make it. do you want stock type high comp replacement, hyper or forged?
the other alternative is that they might be able to point you at substitute piston that is similar to or just slightly larger than your stock bore which you can use in place of what you have. you might could wind up running a metric motorcycle piston with one of those ultra thin ring packs.
Right.
TA seems to be the best bet for what I want, which is to restore it as close to stock as I can.
There are valve marks on two of the pistons, and a nice wear ridge on the cylinder wall.
Machinist says we should get new pistons, so I was trying to put together a list of options to go over with him.
So far I have found only these options for a stock bore;
1) Sealed Power W279P
2) Silv-O-Lite 1724-STD
3) TA Performance TA_1601
I'll have to give TA a call for to ensure they have high compressions pistons beforehand, it seems. Thanks!
One other supplier which shows 340 pistons with both compression ratios is www.egge.com
Some suppliers may be able to reference the original Buick part nos. The high-compression 340 piston and pin set in standard size is 1395312. The low-compression in standard is 1395184. The parts book has oversize part numbers too if required.
Www.buickfarm.com shows to have the OEM Buick standard size part nos in stock. Don't know if they would have enough for a full set of 8 or an oversize set. A single piece could serve as a model for other vendors if nothing else works.
Modern composite head gaskets will probably be thicker than the original .020 steel gaskets. This will drop the compression ratio some from the original numbers. This will help in avoiding knock from lower-octane modern fuels. Also better for use with any block or head imperfections. Buick used a thicker .045 gasket (approx the modern thickness) occasionally. Dealers were also instructed to install them on cars with difficult engine-knock problems.
Some suppliers may be able to reference the original Buick part nos. The high-compression 340 piston and pin set in standard size is 1395312. The low-compression in standard is 1395184. The parts book has oversize part numbers too if required.
Www.buickfarm.com shows to have the OEM Buick standard size part nos in stock. Don't know if they would have enough for a full set of 8 or an oversize set. A single piece could serve as a model for other vendors if nothing else works.
Modern composite head gaskets will probably be thicker than the original .020 steel gaskets. This will drop the compression ratio some from the original numbers. This will help in avoiding knock from lower-octane modern fuels. Also better for use with any block or head imperfections. Buick used a thicker .045 gasket (approx the modern thickness) occasionally. Dealers were also instructed to install them on cars with difficult engine-knock problems.
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Good to know. After the rebuild, a thick head gasket will give me a little leeway in octane and a bit lower compression. Thanks
I'm gonna see what the machinist thinks about just replacing the two pistons with NOS, or buying 8 NOS.
That website had 22 in stock, amazing! Thank you.
Pulled the fenders off for some hardcore maintenance and prepping.
The machine shop will give me an overbore number today, likely .030 over.
I'll need a new camshaft, as well. I'll likely just let the machinist choose the camshaft,
but I was curious as to which camshaft you guys might choose, if it was up to you.
Any suggestions?
The machine shop will give me an overbore number today, likely .030 over.
I'll need a new camshaft, as well. I'll likely just let the machinist choose the camshaft,
but I was curious as to which camshaft you guys might choose, if it was up to you.
Any suggestions?
Attachments
Pistons showed up in the mail, and I handed them off to the machine shop.
Silv-O-Lite .030 over
Silv-O-Lite .030 over
