Hello, I recently bought ctr pistons for my b18b and was wondering if i would need a tune afterwards and if so could i just use my stock ecu to get it tuned or would i have to get it chipped and socketed. I probably sound like a idiot asking this.

 

you need a tune...save up for a vtec head..it'll yeild u alot more power than just throwing in CTR pistons. I personally wouldnt even bother putting those pistons in until i got a b16 or GSR head for my car and made it LSVTEC..you might as well do it all at once while you already have the motor out. save up, do it right, or hate urself in the end for wishing you were more patient.

 

I have another engine sitting up on the stand that i plan on going lsvtec on and completely build up. But i have to replace my pistons in my car anyways so i figured i mine as well just put the ctr ones in. So i still have the question of do i need to mod my ecu to get it tuned or can i just use it while being stock

 

do ctr's even work with ls rods?

I know you cant use some of the b-series pistons with ls rods but I forgot which?
I would definatly search info on that matter before I open up the package or especially the motor!

 

i believe you have to have a shop modify the piston (cut out some of the skirt) or something along those lines to get them to work with the LS rod.....someone correct if i am wrong..but i know there its one piston/rod combo where you have to do this..and i think CTR/LS is that combo

 

and your raising the compression on ur car by alot so yes you need a tune

 

just a suggestion, I use weisco LS pistons because they offer a lil more compression, are lighter than ctr's, and are also a direct fit.
and yes either way you need to chip your ecu and have it tuned. stock cams wont really like that much compression too. I would recomend at least crower 403's.
high comp. + 403's + good tune = very sweet running LS !!! :D

oh and I totally agree with the guy that said to go ahead and go LS Vtec, but if your set on non vtec then the way I stated above is the best rout to go.
I just sold a set of crane cams that were pretty close to crower's 403's to a guy that's doing the same thing. I had the crane's in my LS swapped CRX with itr pistons and a tune. It went 7.80's 1/8 mile with a 50 shot too.

 

ctr pistons(P30) are a direct fit to B18B1 LS rods and is a common swap for pistons in the LS engine.
https://honda-tech.com/forums/showth...6#post40572696
http://en.wikipedia.org/wiki/Honda_B_engine#B18B1

Raising the CP to around 11:1 with the CTR pistons will require you to get the thing tuned, and you will have to run premium pump gas (91+ octane rated) to prevent premature combustion

 

i thought that b16a pistons were p30's and ctr pistons were pct's?

 

Yeah the ctr pistons go right on. But thanks for the questions i had about the ecu, I just got a p28 ecu chipped and tuned on crome.

 

I'm almost positive thats the itr/ls combo im about 99% sure.

 

I was mistaken the PCT's are the CTR pistons and of which i am unsure fit directly onto the LS rods. I get B16a/b's mixed up.

Here is a little chart i found for standard B18b engine CR w/different sized pistons:

Least Compression ------> Most
LS, GSR, ITR, P30, PCT

 

High Compression motors need very precise timing and ignition if not then you will have detonation is a knocking type sound NOT GOOD sounds like its coming from the head and exhaust manifold, i would know i have a LS Vtec with CTR pistons and ran a regular ls vtec map good thing i found somebody i know with a basemap for the exact motor setup and yes tuning will be needed but it will be a fast rocket because i smoke lots of cars like rsx type s and g35 and more bring them on. and yes they fit LS rods you need the nippon or oem is the way to gooo.

 

yes you are right i had to take my pistons to my dads machine shop and we had to take .020 of an inch off overall so .010 off each wall and make sure they all weight the same if not then get it balanced.

 

well i usually ignore these post, i just love reading the people that chim in like they do it all day but i will offer some advice you wont take.

they will fit ls rods but you have to mill 1mm off each side of the rod small end for proper clearance. if you mill the pistons there trash and will crack in a few runs, also ctr pistons are not as good as b16 pistons (that fit on the ls rods with no mods) because its been proven by quality builders like lasky and endyn that the high dome of the ctr piston disrupts the full burn.

well its flame me time. happy ghetto engine building

 

also for the original poster please dont listen a word that ls vtec da is preaching. when someone says they smoke cars all day. theres cars cant smoke a bicycle. you wouldnt balance the pistons and call it a day. the entire totating assy needs to be balanced or it will die no matter how good your tune is. and chips just make your car rich as ****. it needs to be dyno tuned it will take 4 hrs. and if its done right will cost more then his car is worth

 

4thgen i wouldnt recommend to anyone to mill their rods on a high rpm spinning motor..nor would i say to shave th pistons either, i just wouldnt use this particular setup at all. and your right the high dome piston does disrupprt the even and full ignition of the fuel...alot of people dont realize the goal is to have the smaller combustion chamber but will the flatest piston possible to obitain full combustion of fuel easily..this is why i always like to use the GSR head because of the smaller combustion chamber design BUT
he didnt say a chip, he said a basemap from his friend with the same setup, which IMO is usually fine if u dont have the cash for tune at that time, and he was referring to crank balanced i believe he said nothing about "getting your pistons balanced"

 

Using CTR pistons on a ls motor is a complete waste of time and money. IMO Using CTR pistons on a ls or any motor for that matter requires a tune and between ecu and tune your going to be spending at least $500. And there's not going to be much of a performance increase with the money your going to spend. If your building another motor anyway why waste the money on the LS? Put in stock LS pistons and use the $500+ on the other motor your building.

 

ctr pistons just weigh a little more and the aftermarket forged pistons are stronger than oem pistons and i have no problems and i have milled each piston and there is no problems as long as the pistons are all the same weight that is pretty much you balance and i smoked my brothers ls vtec turbo hatch on 6 pounds of boost and it is not a waste of time i have a stock exhaust and cat i get rid of it and get stage 2 cams and valvetrain and straight 2.5 inch pipe which i have i put that on and get a tune i will be probably running in the 13's quarter mile its perfect for NA

 

ok nobody cares what you have, because hes not doing lsv

 

i am just trying to say that a ctr lsv is not that bad like you all you guy say it is, so i am using a example i know you probably don't care so what i am just trying to help him by giving info ok.