Sup guys, I'm planning to get my b18c1 rebuilted with either new b16a pistons or jdm itr pistons. From my understanding the b16a will have a slight higher compression than the jdm ITRs. Both should be around 11.36:1 am I correct? But will the ITR's heat coated pistons have any advantages over the b16a piston? Will the b16a piston take the same abuse as the ITR on high rpm? I believe the b16a are a lot cheaper than the ITRs? I'm going to get all bearings replaces, replace water pump and oil pump, know if the ITR is different from the gsrs? Also, anyone have a idea how much it would cost to balance and hone the motor? and when balancing, does everything need to be assembled or taken apart? Anything else I should look into? I was planning to swap over a ITR head afterwards, after I get the car reffed, Will I be fine with the 11.36:1 compression? thanks in advance

 

i thaught that the itr's would be higer cr..

 

no I dont believe so. Anyone else??

 

the C/R difference between the JDM ITR and USDM SI pistons is really close, almost no difference. but i think the B16A pistons have just a very slight bit more dome than the JDM ITR, therefore yielding just a hair more C/R.

$$ wise the B16A would be the way to go, since they are much cheaper normally.
but the coating on the ITR pistons helps against friction from boost or high rpm.
so they're good for boost, high C/R and rpm, and N2O applications. yes it's about 11.35:1 C/R from what i remember, a B18C1 with B16A pistons, 81mm bore size.

you need to remove the crank, rods, pistons etc when rebuilding a motor. when everything's apart you can have the crank balanced, the cylinders bored and honed and the bearings gauged. just make sure to get the correct bore size pistons. if the sleeves nead to be overbored from an out of round condition, then you'll need oversized pistons to keep the clearances to spec.

 

If I'm going to get a type r head along with jun type 3 cams reving close to around 9k, is it reccommended that I go with the JDM ITR's or I would be fine with the b16a pistons? Also about getting the motor balanced, do each individual part pistons,rods,and crank suppose to be balanced separately? Any other reccomendations on what I should do to the block before assembling it back together? knife-edging,micro-polished crank,etc??? thanks

 

For your b-series CR questions.

http://www.bojangs.com/calculator/

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B16B &raquo;</TD></TR><TR><TD CLASS="quote">For your b-series CR questions.

http://www.bojangs.com/calculator/ </TD></TR></TABLE>That's a cool little CR calculator, does anyone know if it's pretty accurate?

 

up

 

talk it over with your engine builder.

 

I'd go with the B16 pistons since they are cheaper and easier to get.

 

Anyone know if the b16a pistons will be reliable enough for my JUN type 3 cams, reving close to 9k???

 

they will be reliable as long as there is oil in the engine and you have used the correct valve springs, and tuned it correctly.

good idea would be to use the b16 slugs, buy all brand new piston rings, and have the bottomend high speed balanced.. that way , it should be a bit more stable when reving as high as you are indicating.

Dont forget to break in the motor... the pistons will leak if you dont do it right

keep this in your mind though... always a good rule of thumb

RPM's Ruin Peoples Motors


Modified by B16B at 9:29 PM 4/14/2003

 

thanks, but will it be worthed it by spending extra for the jdm itr pistons or I will be fine with the b16a pistons? What results could happen if I go with the b16a instead of the jdm itrs? pinging, detonation?

 

the b16a pistons will be lower compression then ctr pistons. therefore less chance of pinging and detonation.. The most important thing to do with high compression motors is to tune on the dyno.


Modified by B16B at 8:50 PM 4/15/2003

 

if you're going to rev the motor high, up to 9K i guess you said before, then you may want to spend the extra $$ and get the JDM ITR pistons. it will keep you around the same C/R as the B16A's but they have the coating on the sideskirts to reduce friction during high rpm use.

but if you're going to keep the rpm lower and closer to stock then save the $$ and use the B16A pistons.

 

As sweet said the JDM ITR's (P73-00) pistons are nice because they have the tetra methyl skirt coating which reduces friction.... This is not totally needed and you'll be fine with standard pistons.... I personally would go with the higher compression ones... I don't build too many motors with JDM ITR's... most people want atleast P30's or PCT slugs... Just my $0.02... Good Luck

 

cool thanks a lot

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HKSone &raquo;</TD></TR><TR><TD CLASS="quote">Anyone know if the b16a pistons will be reliable enough for my JUN type 3 cams, reving close to 9k???</TD></TR></TABLE>


Wow, I have almost the same setup. well, jun 3's are still sitting at home somewhere , but I am using B16a pistons too on a B16a head with ITR internals. Like everyone else, the extra is nice to have but for the $$$ its your choice.

 

cool, hey bert-o, where did you pick up a set of b16a pistons? anyone know where I can find a set for cheap with rings? itr with rings is around $300. Did you guys have the bottom end balanced??? what else did you guys do to the bottom end? would polish rod and crank make any difference? thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HKSone &raquo;</TD></TR><TR><TD CLASS="quote">cool, hey bert-o, where did you pick up a set of b16a pistons? anyone know where I can find a set for cheap with rings? itr with rings is around $300. Did you guys have the bottom end balanced??? what else did you guys do to the bottom end? would polish rod and crank make any difference? thanks</TD></TR></TABLE>

i can't remember if you mentioned what size piston you needed, such as oversized 81.25 or 81.50mm. i have a B16A block that i may tear down and piece out with standard size 81mm pistons in it. it's low mileage and all stock. i also have brand new OEM piston rings in standard bore that i was going to use on a rebuild but no longer need at the moment. if interested in both as a set LMK.
if not i'm sure you'll find a piston set somewhere else since the B16A's are pretty common.

 

I haven't taken the engine apart yet so I dont know which size I will need. The motor has around 130k, think it will need to be bored out? so pistons rarely wear out? I wanted to replace everything with new parts since I'm getting new bearings, water pump, oil pump etc except rods and crank. B16a pistons from the factory cost as much as the ITRs around $300 with rings, so when people say b16a pistons are cheap is because they are getting it used? I'm going to get the bottom end balanced, should I also polish the rods and crank? thanks

 

with 130K on the block the cylinders may be out-of-round and therefore need to be slightly overbored to get them back into spec. but if the bore is not oblong in shape and doesn't have much wear, then a quick cross-hatch honing will do just fine so it can accept new piston rings.

as for the lower cost of B16A pistons, i assume most people pick up a set of used ones with low mileage so the side skirts have minimal wear. so then they cost much less than $300.

shotpeening the stock rods is a good idea if you have some extra $ but not enough for aftermarket rods, or if you don't need aftermarket rods to begin with.

 

sorry but on the b18c1 small end of their rod ..the width is narrower than the piston slot on a b16a.

remember that the b16a guys have to mill their rod small ends to a narrower width to accept ITR/CTR pistons? well the reverse is true when you use b16a pistons on a b18c1 rod.

so I hate to break the news to you: of the 2 choices listed, you really only have 1 choice. I'm surprised no-one informed you of this on this thread before me.

 

so machining the rods will be necessary for b16a pistons to fit? anyone know for sure?

 

the B18C1 rod is too narrow for the B16A piston slot. You don't machine the rod small end further to make it even narrower.

On an LSVTEC or B17a, the people wanting B18C5 or JDM ITR B18C or B16B pistons ("R"-family: ITR, CTR, GSR 3rd gen), must machine their B18B/B17a rod because it is too fat for the narrower "R" family piston's slot.

The B16a piston would wobble too much on your B18C1 rod.

Do you see what I am getting at?

I cover this in one of our website's Articles:

http://www.team-integra.net/se...ID=20