Basically what I'm looking for is what kind of changes need to be made for these pistons (ie valves, valvetrain) Do the cylenders need to be honed? Which rings to purchase. I'm looking for clearence issues or other parts needed to do the job. I'm looking for STD piston size not larger pistons so no boring of the block. And for all those who ask it will be street driven with some track time. Any advice is welcome. Thanks in advance.

 

hate to be a dick, but:

Your search for CTR Pistons returned 78 results.

 

you can swap over the pistons without having to modify your head. i would bet you would need to hone your walls. i just did an LS bottom with some pr3 std bore pistons and new honda std bore rings. honed it very little. just enough to get the cylinder looking pretty nice. didnt take much metal off the walls but it will make a difference on how the rings act. the rings still ended uip gapping within spec, but it was towards the max limits. i would suggest getting the O/S, but if you have your mind set on it:
-buy pct or pr3 pistons
- take the block to a machine shop and have them
-----hot tank the block (and head while its offf)
-----mill the head flat
-----Deck the block
-----show them what you want to put in the block and have then run a few strokes in the hone.
-----R&R the pistons on your rods
- Say thank you to your shop
- Put it all together
- put it back in
- have fun

 

I've got a pretty reputable shop in mind. They seem to do good work. I definitely want to keep stock bore if all checks out ok. The car now has 57k so I think it would be best to hone it. Anyone know what kind of compression will result with this setup?

 

well with 57k i would say you are going to have a lip. for the price of boring a block, i would do it. if you have some downtime to play with, have them look at the block when you bring it in THEN order pistons based off what they say. most reputable shops will be honest whether or not in their opinions if the block NEEDS to be honed, of if its a good idea.

11.75ish as per cspeed - http://www.c-speedracing.com/h...c.php

 

Thanks man. I did some searches and found out more on it. Maybe I should just go with the JDM ITR pistons.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sucka306 &raquo;</TD></TR><TR><TD CLASS="quote">

11.75ish as per cspeed - http://www.c-speedracing.com/h...c.php</TD></TR></TABLE>

Actually that's quite wrong.
CTR pistons are 12.5:1-ish and .25 OS are 12.8:1 in an ITR block/head.
Search some of Omniman's posts from a while back for 'correct' compression calculations.

 

will do. thanks for the heads up. i dont know much about the ctr pistons in the ITR block. i am an LS guy and never had any firsthand dealings with pct pistons. i'll check out his info

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sucka306 &raquo;</TD></TR><TR><TD CLASS="quote">will do. thanks for the heads up. i dont know much about the ctr pistons in the ITR block. i am an LS guy and never had any firsthand dealings with pct pistons. i'll check out his info</TD></TR></TABLE>

Don't quote me, but i think the reason the c-speed calc is off in this case is the volume of combustion chamber in the head? Something along those lines. If I find the thread where omniman posts the correct compression numbers, I'll post a link.

 

Just like Chris said most online compression calculators are inacurate because of the inaccurate info on the compression height of each piston.

Here are calculations including compression height provided by Omniman and OEM headgasket.

PR3 head/B18C Block

STD = 12.58636786521145
.25 OS = 12.649248792586258

* Info taken from archived post, credit goes to Altered and Omniman.

Here is the link: https://honda-tech.com/zerothread?id=717928

 

Thanks Tommy I was trying to find that same thread... lol, I'll save it in my notepad for future reference.