im doing a ls vtec setup and using the itr pistons. many shops that i go do would recommend me on boreding my pistons to .25mm and other shops said 1mm. which and how many mm will work good on a lsvtec setup. any opnions will be very helpful.

 

Boreding? WTF is that?

Are you talking about using oversized pistons and BORING your cylinders to fit the larger pistons?

 

dude, if know anything about ls vtec you should know, or heard of this, when putting any type of pistons in the block you have to bored your pistons a certain mm. enable for your car to run well. because these piston are not made for the ls block. somthing like that. so if you dont know stf up

 

You only need to bore you cylinders if you buy oversized pistons. If your going to use stock ITR pistons.... why would you bore..the pistons wouldnt fit your new block! And you dont bore the pistons..... you bore the cylinders. So only bore the block if you plan on buying oversized pistons.


[Modified by CRX_VTEC, 6:17 PM 8/13/2001]

 

if you are using new pistons it is a good idea to bore the block .025 over (twenty five thousandths) and order the same pistons. that is the standard amount anything more should only be done if there is a reason (like imperfections scratches that are deeper then .025.

 

TY, you're an idiot. I seriously hope you get some help soon. And I know more about LS/VTEC than you could ever possibly hope to.

What's your address, I'll send you a quarter so you can go buy a clue.

 

you seem to be a smart *** chump.

 

Ty- that was a smartass comment that you made. The other guys are right. And all the results I've seen from overbore vs. standard bore indicate= NO BIG DIFFERENCE. Don't waste the money.

 

tysir I think you are refering to boring the block to fit an over sized piston, either that or you are talking about milling 1mm off the inside of the piston so the ls rod will fit. I had my lsvtec built with a 20 over piston and they had to mill the rod I believe 1mm on each side to fit the piston.

 

yeah thats what im talking about EVOCELICA. now y would you want to do that? milling the pistons from the inside. my back people sorry bout that.

 

Ok first of all the terms are boreing and honing, boring is when you take material off the inside of the cylinder wall(usually around .10-.20 over) to accomidate larger diameter pistons, now honing is when you use a triple stone honing machine it is an attachment that goes on a drill or machining rack that takes out very very minimal(less than .0001in) material. Honing is done when you take out pistons and put them back in, either because you are using a different type of piston or just putting new rings on your old pistons.

Now with that said the ITR piston will fit in the LS block because they are both 81MM pistons what you need to do is HONE the cylinders not BORE the cylinders(unless you went with oversized pistons then BOREING is required), now what EVOCELIA is talking about is where the rod is connected to the wrist pin, the LS rod is wider than the space on the underside of the piston where the rod fits in on the wrist pin so you have to make the top of the rod narrower for it to fit in the piston.

And just for the record B18C-EJ1 knows his $hit...he has been by my side putting his blood and sweat into many engine rebuilds and build ups including over a dozen LS/VTEC and CR-VTEC builds!!

This is a cylinder before honing:



and a cylinder after honing:




[Modified by KawiGreenHYBRID, 3:58 AM 8/15/2001]


[Modified by KawiGreenHYBRID, 3:55 PM 8/15/2001]

 

Smart *** you got right, chump I am not. You better check yoself.

Go read some books before coming here and trying to lay the smackdown. Because you just look stupid trying.

 

aaaaaaaaahhhhhhhhh freshly honed block, that is one beautifull picture. You know your a Honda nut when you love looking at pictures of newly built blocks......

 

Ok first of all the terms are boreing and honing, boring is when you take material off the inside of the cylinder wall(usually around .10-.20 over) to accomidate larger diameter pistons, now honing is when you use a triple stone honing machine it is an attachment that goes on a drill or machining rack that takes out very very minimal(less than .0001mm) material. Honing is done when you take out pistons and put them back in, either because you are using a different type of piston or just putting new rings on your old pistons.

Since we are on the topic of smart asses... you are close but not correct either. When you bore (or hone), I hope that you are not removing 0.10-0.20" or MM off the cylinders.... if you don't know your standard or metric scale.. 0.10"-0.20" is around 1/8" of an inch. Generally you bore 0.020"-0.025" THOUSANDS of an inch depending on the piston design and manufacturer. Standard Honda overbore is 0.025".

Honing 0.0001mm is hardly removing anything at all.. why bother honing??? 0.0001" (read: inches) would be more practical.

Also, when you narrow the small end of the LS/B20 rod to fit a VTEC piston, you must remove MORE than 1mm on each side. You need at least 0.30" or 1/16" clearance/play on each side of the rod. If you only remove 1mm, you will have MAYBE 0.010" play on each side.. that is pushing it.

HTH.

 

oops.. correction on the small end of the rod modification: you need to have at least 0.030" or 1/16" clearance.

 

True true...

One other thing, Boring is to remove large imperfections in the cylinder walls or to use oversized pistons, Honing (spelling? it's really late) is only to resurface the cylinder walls for the new rings to seat upon.

I use a bottle brush style hone, I like it much better than the triple stone version.

Usually when someone talks about 10 or 20 over pistons, they are referring to Inches, and it looks like this .020 That's 20 thousandths of an inch.

G3 is correct, and I agree.

 

I concure I left out the 0.0 on the specs my bust I was in a hurry to get off the computer. My bad thax for the correction...had too many things going on last night.

**disclaimer** I really am not stupid, I just look like it now




[Modified by KawiGreenHYBRID, 3:55 PM 8/15/2001]

 

what if i used the usdm itr pistons with the rods will i have to hone the cyclinder or mill the pistons.

 

If you use USDM ITR pistons and put them on LS rods you will have to modify the rod to fit the piston yes, and yes you will need to hone the cylinder walls...this needs to be done ANYTIME a piston is put back into a cylinder.

And just for fun here is two pictures of my ITR pistons:





Oh those are USDM ITR's by the way


[Modified by KawiGreenHYBRID, 6:55 PM 8/15/2001]

 

http://tiiite.b16a.com/pistons.htm Here is everything you ever wanted to know about Honda Pistons...

Hope this helps resolve your questions........

 

can i still use my ls rods or can i use just the type r rods. is there a difference?? what would be better or differences in compression ration when talking about jdm or usdm? will jdm perform better than usdm or basically the same??

 

You have to use your LS rods, the ITR's are a different length.

 

Agreed.. the big end of the rods are different as well. they have different widths. You must match the rods to the crank you are planning to use.

 

man you guys have been so helpful i dont know how to thank you guys. people up the LBC be shisty with them infor. no body wants to help out each other. thanks for everyone for their commets and advise. im sorry for being a dick too, for all the racer that i kind of pissed of my back. now i know i can rely on my fellow racers up in honda-tech. again im sorry my racers.

 

JDM ITR pistons yeild about .5 a point of compression ratio more than USDM pistons...read the link that was given it tells you anything you want to know about B series pistons.