ok im wondering what numbers and about how well this set up will work.
b18a or b block (have both)
b16 pistons and rods
b16 head
aem ems
blue print ls/vtech kit
im wonderin how good un-boosted and how much the compression is going to drop of coarse im gonna boost it later but need to know if it will run decent un-boosted cause i know the pr3 rods have a smaller stroke.

 

you cant run b16 rods with a b18 crank.

 

why is that

 

b16 rods are shorter than b18's. you need to install the b16 pistons on b18 rods, the b16 rods r too short and idk what would happen there aside the piston not coming up high enough to create decent cylinder pressure. go s300 instead of aem. less problems and more user friendly, as for compression ratio? you will be fine as long as its properly tuned, compression ratio has nothing to do with turbocharging a motor, its all in the tuning. s2k's have pretty high compression ratios and yet untouched have made 700whp once turbocharged and tuned

 

Not true. It's actually the other way. B18 rods are shorter than B16 rods. That's part of the reason B16's (especially B16B) can rev higher than B18's. The rod length to stroke ratio is larger (not simply because of a shorter stroke) & allows for higher revs since the piston experiences less side loading and longer TDC & BDC dwell time (among other reasons).

So yes, B16 rods will not work in a B18 block without major modification to the block.

Edit:
B18 & B20 rod length: 137mm
B16B rod length: 142.4mm
I double checked by setting an LS rod & B16 rod next to each other to prove it to myself.

 

You could do it but you'll have a very low compression, somewhere around 9.1:1.. the rods of a b16a(pr3) are shorther than the b18a/b. the b16b has the same deck height as a b18b but a smaller stroke so it have longer rods.. the b16a has the same stroke as a b16b but with a smaller deck height therefor shorter rods.. technically it could be done but you won't really benefit you running without boost.. your best bet is to put the b16a pistons on the b18b rods, which will put you around 11.5:1 compression.. then when you go boost just buy aftermarket internals for your block..

 

Well if I was wrong I apologize. There's nothing that bugs me more on forums than wrong info, so thanks for correcting me. I'll have to go double check my rods cuz I swear it was the other way, but my eyes may have been playing tricks on me.

 

short of the long: you cant run b16 rods in an ls.

 

your right on the b16b rod but if you would learn to read the op was asking about pr3 rods and if you did know anything about honda motors you would have realized that was a b16a you dumb ****

 

chill with the name calling, it's not necessary.

 

how much of a diffrence in commpresoin hight do the b16 pistons have compared to the b18 piston

 

are we in a noob forum, someone said the ctr deck height is the same as a b18b ...ummm nottttt...

ctr and itr blocks are the same thing, if u put a b18c5 crank rods and pistons in a b16b block, you would have a itr block that says b16b lol

and by the way the ls rod length is 137mm b16 length is 134

 

not sure on that one, never thought bout it. i just know the b18a/b pistons have a -3.20 piston dome displacement (cc's per cyl) and the b16a usdm have a 6.01 piston dome displacement.

if your going to leave it all motor or boost it later you will more than less need the proper turbo, manifold and supporting mods and of course proper tuning. as for ems scrap that aem system, they have a tendency to destroy the ignition module (been there and so have others). stick with the hondata s300 which is by far top notch to any other system out there. if you have a stock ls longblock just freshen it up if ur going budget and use a oem honda genuine ls headgasket and bolt the vtec head on. you may safely see upto 400whp and roughly near 290 tq. its been done plenty of times. if not budget u can just buy a set of rods and some cp pistons and go make over 550whp on stock sleeves with tuning.

but regardless if you keep the ls pistons in or b16a pistons in, u need to use the rods made for that block unless a stroker kit is involved. either way you will be able to boost on either pistons, correct tuning is key to any motor whether honda or not. compression also has nothing to do if you boost it or not til a certain point if the compression ratio is way too high like in the 13.2's n up

so its up to you really tho but i wouldnt do the aem since it has a tendency of requiring more parts to run this n that while hondata is just plug it in and tune it no-matter what hp your looking for