bored block

camdiddy · 11-17-2009, 03:56 AM

Hola!

The block I am looking at buying from someone for my rebuild has been bored 40 over and I was wondering if I am able to use stock gte pistons or if I will need to buy different spec pistons. If so, do u guys have any recommendations for pistons that wouldnt destroy my wallet?

Thanks

MA70-3.0GT · 11-17-2009, 05:10 PM

Err, if I remember correctly .40" is over 1mm oversize so no, I'd very much doubt standard pistons would last more than a couple of days before rattling themselves to death. Generally I use Wiseco pistons for my rebuild work. Not 100% they do them for this engine but it's likely as they do most applications & if it's not listed then you can usually give them the spec. you require & they have something suitable in stock.

No doubt someone with more experience of these motors has a different recommendation for you if you give it a while, but personally I've never had any issues with Wiseco in quality or pricing...

two-step-n · 11-17-2009, 05:35 PM

the block is bored .40 over there for you will need .40 over size pistons

cre · 11-17-2009, 07:34 PM

I think Toyota sells pistons in larger sizes for bored engines... .040" may be the largest they carry though. If anyone feels like it you could research the part numbers on this page: http://www.cygnusx1.net/Supra/Librar...rts/13101.aspx

Regardless, I'd still go aftermarket. If you're going to have it all apart the wallet is the only reason to reconsider forged internals. At this point I'd go with some GOOD pistons (wiseco or probe, for example) and forged rods.

If money's tight, NPR makes a stock replacement which is available with a Teflon coating. They're affordable and will perform well enough for slightly modded cars. They are still cast though and you have them balanced and matched, but they're pretty good.

camdiddy · 11-18-2009, 12:43 AM

Cool. Thanks for the info. Looks like I am going to have to set aside a little more cash for this thing. and I assume I will need aftermarket rods to go with the pistons as well, correct?

cre · 11-18-2009, 12:50 AM

No point in sticking with stock rods if you're going with premium pistons.

Actually, the original rods are more likely to fail than the original pistons would have been. New OEM rods would be fine, but I'd have them balanced and cryo treated... depends on your goals with this engine.

11-17-2009, 03:56 AM	#1
camdiddy Stock Join Date: Jun 2009 Location: Avon, IN Posts: 6	bored block Hola! The block I am looking at buying from someone for my rebuild has been bored 40 over and I was wondering if I am able to use stock gte pistons or if I will need to buy different spec pistons. If so, do u guys have any recommendations for pistons that wouldnt destroy my wallet? Thanks

11-17-2009, 05:10 PM	#2
MA70-3.0GT 12psi boost Join Date: Oct 2009 Location: Crewe, England Posts: 356	Err, if I remember correctly .40" is over 1mm oversize so no, I'd very much doubt standard pistons would last more than a couple of days before rattling themselves to death. Generally I use Wiseco pistons for my rebuild work. Not 100% they do them for this engine but it's likely as they do most applications & if it's not listed then you can usually give them the spec. you require & they have something suitable in stock. No doubt someone with more experience of these motors has a different recommendation for you if you give it a while, but personally I've never had any issues with Wiseco in quality or pricing... __________________ '89 MA70 Supra GT aero 3.0turbo JDM, Rebuilt motor, K&N intake, 3" stainless turbo-back. New turbo and braided line kit... '89 Honda NC27 400, NC23 cams, open pipe, PC36a shock & possibly Showa USD forks... '83 Yamaha 29R XJ750E-II, number 69 off the line, only runner in the country? Original except Koni shocks '95 Honda PC26 CB500R, Winter hack, hateful, trying to sell it I'm not paranoid, they really ARE after me!!!

11-18-2009, 12:43 AM	#5
camdiddy Stock Join Date: Jun 2009 Location: Avon, IN Posts: 6	Cool. Thanks for the info. Looks like I am going to have to set aside a little more cash for this thing. and I assume I will need aftermarket rods to go with the pistons as well, correct? Last edited by camdiddy; 11-18-2009 at 12:47 AM.

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11-17-2009, 05:35 PM	#3
two-step-n 3" Exhaust Join Date: Oct 2009 Location: mesa az Posts: 51	the block is bored .40 over there for you will need .40 over size pistons

11-17-2009, 07:34 PM	#4
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	I think Toyota sells pistons in larger sizes for bored engines... .040" may be the largest they carry though. If anyone feels like it you could research the part numbers on this page: http://www.cygnusx1.net/Supra/Librar...rts/13101.aspx Regardless, I'd still go aftermarket. If you're going to have it all apart the wallet is the only reason to reconsider forged internals. At this point I'd go with some GOOD pistons (wiseco or probe, for example) and forged rods. If money's tight, NPR makes a stock replacement which is available with a Teflon coating. They're affordable and will perform well enough for slightly modded cars. They are still cast though and you have them balanced and matched, but they're pretty good.

11-18-2009, 12:50 AM	#6
cre Toyota Racing Development Join Date: Apr 2007 Posts: 5,038	No point in sticking with stock rods if you're going with premium pistons. Actually, the original rods are more likely to fail than the original pistons would have been. New OEM rods would be fine, but I'd have them balanced and cryo treated... depends on your goals with this engine.