5STAR3

I would like some input.

here is the deal. I can get the PR3 pistons w/rings for $325. or i can get the JDM ITR pistons w/rings for $300.

my problem is i dont know which to go with. The ITR's come with the coating, however the rods(PR4) need to be modified to accommodate the pistons. On the other hand the PR3 pistons fit onto the PR4 rods just as they are.

so i guess my main question is, is the coating worth the trouble of having the rods shaved, or should i just go with the PR3's. they both will yield the same compression.

gfunkmos37

i would like to know aswell

piles

Yes it is worth the trouble to get the itr's. What block is it going to be going into

5STAR3

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by piles &raquo;</TD></TR><TR><TD CLASS="quote">Yes it is worth the trouble to get the itr's. What block is it going to be going into</TD></TR></TABLE>

B18A/B

piles

are you going overbore or are you going to stay same bore. If same bore I would go pr3. Thats just me I have overbore itr in my ls/vtec but it is all in what you want pr3 is going to give you a higher compression. So it is all in what you want to do. Are going to go all moter, turbo, nitrous, and all that other good stuff

5STAR3

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by piles &raquo;</TD></TR><TR><TD CLASS="quote">are you going overbore or are you going to stay same bore. If same bore I would go pr3. Thats just me I have overbore itr in my ls/vtec but it is all in what you want pr3 is going to give you a higher compression. So it is all in what you want to do. Are going to go all moter, turbo, nitrous, and all that other good stuff</TD></TR></TABLE>

it says in my original post that they both yeild the same compression, which they do.

my question is; is the coating on the skirts of the JDM ITR pistons worth getting the rods shaved? or do i stick with the PR3's which need no machining to fit the onto the rods.

1quickhatch

I thought ITR pistons would yield a higher comp than PR3'S........... If not then P30 pistons would be even higher in the comp department. Anybody that can clarify this??

No-Gi

ITR just a bit higher I believe. There was a post on this not too long ago, see if you can find it.

There, I think thats it.

https://honda-tech.com/zerothread?id=717928

piles

I would go with the itr's

3.504

pr3's have a good chance of being higher c/r.

v1=cylinder volume
v2=deck clearance
v3=head gasket
v4=chamber volume minus dome volume

<U>v1+v2+v3+v4</U> = comression ratio.
V2+V3+V4

the pr3's are 10:1 w/ the tiny 3.047 crank, figure in the 3.504 crank and you come up w/ some crazy numbers.

i'd go ITR's, i feel the pr3's will yield too much compression... ie, run too hot in the LS block w/o squirters. i'm not sure, i'd like to see the math figured out, so if you do so and come back in here, let me know. just remember that you dont have the oil jets in so there wont be any cooling effect in the LS block (unless you threw some in)

NSTY Z33

PR3 wouldn't be higher comp in 1.8L??

5STAR3

ok, i didnt ask what piston yields what compression.

in my set up the pr3 will have a cr of: ~11.6

and with the JDM ITR's it will be: ~11.6

dont believe me? i dont really care, check out the 2 sites.

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

http://technet.ff-squad.com/cr-calculator.htm

my only question is.... is the coating on the skirts of the ITR pistons worth the trubble of havng the pr4 rods machined?

3.504

i dont think its worth it... i'd say screw the machining and go pr3's

riceball777

pr3's or p30's

1quickhatch

I second that thought. Also the PR3's can withstand more nitrous if you choose to go that route later on.

radeon

i have pr3's in my ls setup and i had to mod the ls rods to make them fit ...i am puting some p30 on a new set of ls rods and i still have to shave the rods ....

5STAR3

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by radeon &raquo;</TD></TR><TR><TD CLASS="quote">i have pr3's in my ls setup and i had to mod the ls rods to make them fit ...i am puting some p30 on a new set of ls rods and i still have to shave the rods ....</TD></TR></TABLE>

i have done a lot of research and i am 99.9% sure that pr3's fit onto pr4 rods with no machining/shaving needed.

here is one post where it gets brought up.

https://honda-tech.com/zerothread?id=634857

radeon

i know they don't .. i have tryed and Mike at RS Machines is the ones that did my rods to fit the pr3's

OLM-02R

go get the p30 higher than the itr or the pr3 pistons...

NSTY Z33

p30 is geting kind of hard and troublesome to get though. pr3, head milled, or thinner head gasket. Another choice is just trade the GSR crank for the LS. Added stroke and compression.

irev210

wow, okay a lot of questions in here...

PR3 and JDM ITR bascily have the same dome. However, the piston to deck heigh on the ITR is supposedly less, rasing the compression.

If you compare ITR to P30 or PR3 the ITR is much beefier over all.

After spending quite some time comparing the two, there are a lot of differences.

P30/Pr3 is great if you just want to attach a b16 piston onto a stock LS rod.

I would go with the ITR if you are more serious about doing lots of racing because it is a much more stout piston.

Regardless, 300+ seems like a lot for pistons/rings

pistons= 165 bucks shipped to you, rings =100 dollars shipped to you

all brand new oem honda... I wouldnt recommend spending 300+ dollars when you can just spend 265 out the door

5STAR3

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by irev210 &raquo;</TD></TR><TR><TD CLASS="quote">

Regardless, 300+ seems like a lot for pistons/rings

pistons= 165 bucks shipped to you, rings =100 dollars shipped to you

all brand new oem honda... I wouldnt recommend spending 300+ dollars when you can just spend 265 out the door </TD></TR></TABLE>

i havent been able to find PR3's for less than $325, and that is from honda with my dealer discount. i know it is more than i should be paying but i cant find them anywhere else..... so if you know a place with all means please let me know.

R-Toyz.com

Will pr3 pistons on Ls rods work on a GSR block and head with an LS crank? Any machining required and valve clearance issues with this setup?

5STAR3

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rtzcom &raquo;</TD></TR><TR><TD CLASS="quote">Will pr3 pistons on Ls rods work on a GSR block and head with an LS crank? Any machining required and valve clearance issues with this setup?</TD></TR></TABLE>

back from the dead.

yes, they will.

hybrid_vtec

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1quickhatch &raquo;</TD></TR><TR><TD CLASS="quote">I thought ITR pistons would yield a higher comp than PR3'S........... If not then P30 pistons would be even higher in the comp department. Anybody that can clarify this??</TD></TR></TABLE>

No, PR3 have a higher dome and yeild a lil bit higher compression than the JDM ITR's, but its not enough to matter really! P30 pistons are really giving you higher compression but still able to drive on the street with Premium gas! And finally CTR will yield you the highest compression of them all, but beware of clearances and running premium gas w/o tuning!

Go with the ITR's(if they are the JDM ITR, b/c USDM ITR's will only give you 10.5:1) b/c they have the coating on them and they yield nearly the same compression as PR3's! Dont worry about the machine shop, its no problem for them to make them fit, and you have to go to the machine shop anyway to have them put on!