ls/vtec b18b rods with ctr pistons

We may earn a small commission from affiliate links and paid advertisements. Terms

1

1badteg

Junior Member
i have a 96 ls integra and have been told the ctr (pct) pistons would fit in the block but the rods on my ls would have to be shortened. my compression would be at 14:1 roughly and thats way to high. so my real question is how can i get this to work? i want to stay under 12:1 compression. any input will be good. thanks in advance.
 
actualy your compression is only gonna be about 12.3:1 if thats still too high, run a thick headgasket to bring it down. a .040" gasket would bring you down to about 11.8:1

no rod shortening necessary. i dont know if thats even possible even if it was necessary.
 
i forgot one piece of information, this is for ls/vtec. so the head would be from a gsr. i need to know quick b/c im real close on getting some ctr pistons.
 
Last edited:
Don't get the ctr get p30 less compression and anything in the 12 's compression range is a lot for daily driving. Not saying you can't do it but I would be real careful with that high compression, or get a real good tune. You don't need that high compression to make power, power is in the head don't forget that.
 
Your compression will still be in the 12's more like 12:3 or 12:5 something like that. I have a question will this be a daily driven car or a track car? You will still be at 12:3 or 12:5 like csrcrxsi stated.
 
12+ compression is fine on 100 octane unleaded. If you are just tracking it, go for it, you'll make great power off of the compression. If you want to drive it on the street at all, go with a little lower compression. Mike (Calesta) was running 12+ CR in his b20 vtec, and blew it up twice. Maybe not due entirely to high compression, but I'm willing to bet it was a factor. I'm running 11.5:1 on 91 octane crapifornia Shell V-power, and I get a slight pinging/vibration at some spots in the WOT. Still not sure if it is pinging or just some weird vibration.

GSRCRXsi said:
no rod shortening necessary. i dont know if thats even possible even if it was necessary.
Click to expand...
I think you're referring to the need for shaving the small bore of the rods to fit vtec pistons on nonvtec rods. I'm not sure if the b18b uses the same rods as the b18a, but if they do, you will need to shave the small ends to fit the pistons on them.
 
Last edited:
If it's a track car get a gsr head then more compression, but before you go after all that compression what cams are you going to run is the question? To me I say use the gsr head for more compression thats why against the b16. But if it is a track car why are you using stock rods just asking not saying they won't work? I was just curious.
 
the stock rods will hold up to 200-250 hp roughly with arp rod bolts from what ive heard and seen. i dont want much more than that. until i decide to break 12's i won't upgrade the rods.
 
i've tried stuffing my ls block with pr3 pistons on ls rods, with my head package, my compression was around 13:1:1 which was a little high since i drive my car somtimes 2-3 days in a row. i went back to the stock ls pistons and can revv that badboy to almost 9000rpm reliably without pinging. but for track use only, with 100+ octane you should be ok. if you want a mix ratio, 2 to 1 is good. 2 gallons of the highest pump gas available, and one gallon of race gas mixed. what you are doing is using the race gas as a booster to the pump gas...it works for me
 
i was going to build my 96 integra into an ls/Vtec but changed my mind cause it was WAY to much work for me..so i have all the parts im tryin to sell..i even have a gsr supercharger to make it a supercharged ls/vtec
 
I have the pistons you are looking for brand new never used with rings & pins.......CHEAP.... Send me a PM if you are interested. And the LS rods will need to go to a machine shop to make the pistons work. Good Luck with your build mang.
 
you can run b18a/b block with ctr pistons, b16 head and make around 12.5:1 compression (tested in my old setup) and run fine on 93 octane pump gas. no pinging, ran it off of a chipped p28 ecu with fields program. the reason they blow up so much is because of the long rod stroke from the ls crank. shorter rod stroke with higher revving = boom. you can safely spin this setup to 8k. anything higher you are putting your rod bearings at risk. i spun mine to 9k for 2 1/2 months before it blew with all ARP bolts/studs. if u can trust yourself not to spin it high than build it, its torquey as hell =) btw, if you use an aggressive cam (i reccomend jdm itr/ctr), set vtec @ 6800 rpm. 6800 = peak torque. when vtec hits you make big power. ill look for my dyno sheets tomorrow. good luck.
 
well thanks all for the input. i just picked up some pr3 pistons and im running them on the ls rods. im just going to get the rods shotpeened and they should hold well. i plan on revving into the neighborhood of 8500rpm on track days and 8250ish any other time. 9k on a ls bottom end needs a hefty setup. i need to upgrade my heads internals first but when i do im going after those itr/ctr cams for some power. thanks again.
 
TAGURIT said:
i've tried stuffing my ls block with pr3 pistons on ls rods, with my head package, my compression was around 13:1:1 which was a little high since i drive my car somtimes 2-3 days in a row. i went back to the stock ls pistons and can revv that badboy to almost 9000rpm reliably without pinging. but for track use only, with 100+ octane you should be ok. if you want a mix ratio, 2 to 1 is good. 2 gallons of the highest pump gas available, and one gallon of race gas mixed. what you are doing is using the race gas as a booster to the pump gas...it works for me
Click to expand...

13:1???? how much was the head milled how much was the block decked?????
 
im building a ls vtec and was wondering if it was safe to use ctr pistons with my stage 3 cams?would the compression be to high?do i have to shortened the ls rods?
 
You must log in or register to reply here.
Back
Top