I checked it out on the c-speed compression calculator and an other CR calculator and both had different result:

The pistons are usdm 2000 si .25 over bore and my head was ported and received a 15 thousand mill, which is abour the CR I would get with a 2 layer head gasket(id be still using oem 3 layer gasket. What will be my compression....

c-speed calculator says 11.7 and the other says 11.3

which one do you think is more accurate.

Will I notice a difference with the si pistons??
thanks

 

why with si pistons.

go for CTR pistons instead. if your gonna tear the engine down to put in new pistons for a .3 or .4 increase in CR then dont bother.

 

I'll go with the CTR pistons over the Si.

 

si pistons wont work with b18xx rods

you need ctr pistons if you want the CR ratio of Si pistons

 

besides the CTR pistons are much better then SI

 

Stock bore USDM B16A pistons should yield ~11.3:1 CR with a stock headgasket. 11.7:1 is probably closer to what you would get with the engine you describe.

I may be wrong about this, but I am reasonably sure that you can use B16A pistons in a B18C even though the wristpin end of the B18C rod is more narrow. I guess I'll find out for sure this summer since I intend to use JDM B16A pistons in my new bottom end.

CTR pistons yield around 12.3:1 with everything else stock, which is more than I'm comfortable with, especially since I'll be using stock cams.

 

yeah buddy there is no point of putting si pistons in a type r your just hurting your self just get ctr pistons if your going to do that

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by non-VTEC &raquo;</TD></TR><TR><TD CLASS="quote">why with si pistons.

go for CTR pistons instead. if your gonna tear the engine down to put in new pistons for a .3 or .4 increase in CR then dont bother.</TD></TR></TABLE>

It should be a 0.7-1.1 increase in compression if it'll be between 11.3-11.7 w/ the Si pistons. Sounds like a good daily driver compression to me, especially if it's close to 11.7.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bob-DC2 &raquo;</TD></TR><TR><TD CLASS="quote">si pistons wont work with b18xx rods
</TD></TR></TABLE>
Where do you get your information? Totally incorrect.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Bob-DC2 &raquo;</TD></TR><TR><TD CLASS="quote">
you need ctr pistons if you want the CR ratio of Si pistons</TD></TR></TABLE>

wtf.....

 

thanks for the info, but 12.3 is way to high CR for me.... We get 94 octane gas but in reality its like 92, so I wont go over 11.7 or so, or else I will ahev to retard timing

I dont want to upgrade my ecu to hondata so the only fuel mods will be tuning with fpr and v-afc. If i put CTR pistons and the car pings, I wont have any other option then using hondata, swap for od1, harness etc...


So are the SI pistons bolt ons, are they worth it???

 

last opinion b4 going to the garage

 

Well, with good tuning you can run 12.3:1 on pump gas. Plenty of people do.

But I understand not being comfortable with it. I'm actually planning on doing the same thing for the same reason. Good luck.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 514_type R &raquo;</TD></TR><TR><TD CLASS="quote">thanks for the info, but 12.3 is way to high CR for me.... We get 94 octane gas but in reality its like 92, so I wont go over 11.7 or so, or else I will ahev to retard timing

I dont want to upgrade my ecu to hondata so the only fuel mods will be tuning with fpr and v-afc. If i put CTR pistons and the car pings, I wont have any other option then using hondata, swap for od1, harness etc...


So are the SI pistons bolt ons, are they worth it???</TD></TR></TABLE>

Why not use the CTR pistons (which fit the ITR rods for definate because I saw them on my rods yesterday ), and run a thicker gasket to lower the compression, TODA make some I'm sure there's some out there for turbo applications that may lower the CR enough for what you want (use a compression calculator to find the thickness you need).

Anyone see a problem with going this route?

 

well, I know for a fact that the si pistons fit with the type r rod, so there wont be a problem. I might have them coated for more reliability. And I dont really need more then 11.7 cr since im not planning on runnig high lift cams(max skunk stage 1)

 

I run CTR's on ITR rods and use 93 octane. Good tuning w/ the hondata and I have yet to have 1 instance of detonation. I just don't jump on the throttle at low rpms and it's fine. Go CTR's, you'll be happy later, IMO.

 

whats the link to the CR calculator again?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Type R Bob &raquo;</TD></TR><TR><TD CLASS="quote">I run CTR's on ITR rods and use 93 octane. Good tuning w/ the hondata and I have yet to have 1 instance of detonation. I just don't jump on the throttle at low rpms and it's fine. Go CTR's, you'll be happy later, IMO.</TD></TR></TABLE>

I agree with you but I dont want to buy hondata, and switch to obd1. Have anyone experienced the si piston in b18c5?

 

the only way id put hondata a¸nd CTR piston is if I eventually put jun 3 cams in the car.

Will 11.7 cr support jun cams?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by OBDI JEDI &raquo;</TD></TR><TR><TD CLASS="quote">whats the link to the CR calculator again?</TD></TR></TABLE>

http://www.c-speedracing.com/h...c.php

 

thank you sir

 

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

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sgT &raquo;</TD></TR><TR><TD CLASS="quote">
Where do you get your information? Totally incorrect.

wtf.....</TD></TR></TABLE>

i think he got his info from this thread..

https://honda-tech.com/zero...age=1

 

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

i think he got his info from this thread..

https://honda-tech.com/zero...age=1
</TD></TR></TABLE>

Well let me clue you guys in, Michael Delaney(Tuan) doesnt know much about
engines and anything he says should be taken with a grain of salt. He's probably
good if you want specs or numbers, but for real world expertise, he has NONE.

 

ouch

 

so anyone experienced the si pistons.....is there a really good improvement in acceleration of the car?