I've been reading a lot about the pros and cons of CTR pistons in a GSR, but was wondering if you guys are running any in your Rs? My R is pretty much stock and I'm planning to replace my rings and thought that I might as well swap out the pistons while I'm at it.

I only use 93 octane anyways and seldomnly drive the car. CTR pistons seem to be fairly cheap and easy to come by, but I don't want to spend money on the dyno and have to buy a vafc, hondata, etc.

What I really want to know is how many of you guys are running CTR pistons in your ITR with stock cams and how long you've had it? Any long time problems or should I just get JDM ITR pistons?

Good thread -> https://honda-tech.com/zerothread?id=535569

 

I have CTR's in my R. On stock ECU and pump gas it would ping. I wouldn't get them with out a stand alone ECU.

 

You can't run them without at least properly (read: machine shop) honing the block, but really, you should go up to the stock oversize.

You also need to having a tunable ECU. Not a cheap or easy thing to do. Doable? Very. Cheap? No.

Warren

 

I have std. ctr pistons in my itr. 91 octane tuned on Hondata with skunk stage 1 cams, it runs well. Its not too expensive to do, just takes some time, with dis/reassembly.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rhetoric &raquo;</TD></TR><TR><TD CLASS="quote">I have std. ctr pistons in my itr. 91 octane tuned on Hondata with skunk stage 1 cams, it runs well. Its not too expensive to do, just takes some time, with dis/reassembly.</TD></TR></TABLE>

how do you pass emissions in California with CTR pistons?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Type-Rare#1248 &raquo;</TD></TR><TR><TD CLASS="quote">

how do you pass emissions in California with CTR pistons?</TD></TR></TABLE>

My friend passed in Bakersfield with ctr pistons in his b18c w/ stock cams. I've heard it was possible from some on this board, but then again I'll have to wait and see.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rdriver &raquo;</TD></TR><TR><TD CLASS="quote">I have CTR's in my R. On stock ECU and pump gas it would ping. I wouldn't get them with out a stand alone ECU.</TD></TR></TABLE>

Maybe you should get them tuned instead of just throwing them on. You can run 13:1 compression and still run pump gas.

 

Yeah, but most of us who would be tearing down our motor would have to have a machine shop hone the block anyway, and you'll need to buy some sort of oversize piston either stock or CTR at that point regardless. The cost difference is minimal, it just becomes a tuning issue from that point IMO.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Warren &raquo;</TD></TR><TR><TD CLASS="quote">You can't run them without at least properly (read: machine shop) honing the block, but really, you should go up to the stock oversize.

You also need to having a tunable ECU. Not a cheap or easy thing to do. Doable? Very. Cheap? No.

Warren</TD></TR></TABLE>

 

If you want 12.5:1 (approx) compression - sure. (since you said otherwise stock) You need to do the things that Warren listed for sure. A VAFC isn't going to be enough, either. The pistons may be cheap, but the overall cost to do the project well - not cheap.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by typer_801 &raquo;</TD></TR><TR><TD CLASS="quote">Yeah, but most of us who would be tearing down our motor would have to have a machine shop hone the block anyway, and you'll need to buy some sort of oversize piston either stock or CTR at that point regardless. </TD></TR></TABLE> if you are just honing, you do NOT need oversize pistons.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by owen_the_soyboy &raquo;</TD></TR><TR><TD CLASS="quote"> if you are just honing, you do NOT need oversize pistons.</TD></TR></TABLE>

 

The datalogs I have on a .25OS PCT'd ITR engine using JUN 3 cams running a startup map, show quite a bit of ignition knock retard, even with only mild throttling. The base timing at the distributor was set to 13 deg BTDC too. I'm not sure how much of it I can tune out.

I recommend something milder, like P30's or P73-00's.

I have std bore P73-00's and it doesn't pull timing at all.

 

I ran std CTR pistons and cams on muegun p28 and passed emissions in texas with no problems...the little trick i know is when you go to get it inspected, put the stock cat and exhaust back on...

 

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

Maybe you should get them tuned instead of just throwing them on. You can run 13:1 compression and still run pump gas.</TD></TR></TABLE>

what? buahaha... good luck tracking down a tuner with ninja skiLLz yo!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nospeedlimit143 &raquo;</TD></TR><TR><TD CLASS="quote">

what? buahaha... good luck tracking down a tuner with ninja skiLLz yo!</TD></TR></TABLE>

what are you talkin about? ive heard of people going that high on pump gas...... well atleast around here anyways we have 93 octane

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by cjames235 &raquo;</TD></TR><TR><TD CLASS="quote">

what are you talkin about? ive heard of people going that high on pump gas...... well atleast around here anyways we have 93 octane</TD></TR></TABLE>

i didn't say it was impossible... but you need to find a real good tuner when you get up that high.

 

We are running stock bore CTR pistsons in SpeedRacer00-667's car. The motor is all stock except for the pistons. The car put down high 170's to the wheels on 93 octane. Yes the car does need quite a bit of fuel, but it has been running well for the past 2,000 miles and all of those miles are racing miles since he doesn't drive his car daily. Also the car went 13.5 off the gas recently at the track.
EVIL

 

I would just use jdm itr pistons .25OS. You will achieve a pinch over 11:1 and it will run good on pump gas. I'd never trade compression for timing any day. After all, compression doesnt make all the HP.

Even then, you could still run a Mugen headgasket to get that extra bit of compression.

-Brandon

 

So what about using the CTR pistons and a Mugen headgasket on a stock motor with Cam gears, would that need a tunable ECU or would the VAFC work?

I also will need rings soon Clouds of blue smoke pouring from car...

 

Would having bigger cams help decrease the chances of detonation??
What this that I keep hearing about dynamic and static compression and how bigger cams decrease dynamic compression

 

i am confused i live in so cal so ya 91 octane im going to be running skunk stage 2 cams with itbs and i am having trouble picking pistons i will be tunning with hondata but i might not have it right away ... would you got ctr with this set up or jdm itr.. i have a gsr.