N/A motor build help

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ejcivic

New Member
hi everyone! i have a b18c1 and well it is ready for a rebuild. I want to do a complete rebuild and do a mild all motor. This is my daily car. But anyways, I want to build a strong and reliable motor and plan on using only 91 or 93 pump gas. I have a somewhat of a tight budget about around $2000 for now. What do you guys recomend for the build?
 
I believe there is an OE piston that you can use that will bump up compression vs. the gsr pistons. I believe the P30's will do the trick, tho I am uncertain on the compression that will result. I'm pretty sure that ctr or itr pistons will yield too high of compression for 91 octane. Someone correct me if I'm wrong. For the valve train I'd personally go with a Skunk2 "stage 2" cam. Make sure to upgrade springs, retainers, and ITR lma's. Add a good header. Hytech replica comes to mind. Lastly, tune the thing via crome or hondata. I think its gonna be tough to do this on a $2k budget, but it would make a rock solid DD setup.
 
The highest octane we have in NM that I know of is 91. So i don't really want bump up the compression to high and then not have the gas for it. I like the ideas for the valve train. I thought the P30 where the ctr??... I was looking on the usdm itr pistons for my setup. and sorry to ask but where you talking about the cam gears or camshafts? How much whp would the setup above yield me?
 
PCT is CTR. If you're not wanting that high of compression, I'd go with ITR pistons.

He was talking about skunk2 camshafts.
 
CTR pistons in a B16A is different from a B18.

Pretty much just build a "Poor man ITR". You can probably go a little higher on compression; ITR pistons will bump up CR a little bit higher than P30s, and can still run fine for street. You'd essentially be spending money on pistons, cams, maybe intake manifold, and I guess rest on tuning and other bolt-ons.

My cousin was able to get 175whp on a LS/VTEC with just Wiseco 11.5:1 pistons(stock GSR head, i/h/e), tuned at RLZ.
 
P30 pistons will make more compression vs ITR which will put you at roughly 11:5:1 and still be good with 91 octane on a good tune. Use a factory head gasket and ARP head studs and rod bolts with new internals and call it a day ;)
98+up ITR camshafts would be a good street cam just add some inner Ex. valve springs since you already have the inners on the intake side and be good for 9k rev capability on a good tune. Good luck with your build up.
 
I should have specified. JDM ITR pistons have slightly higher compression than P30s, but P30s do indeed increase compression more than USDM ITR pistons.
 
And I can tell you that's not true. P30 has a larger dome, but the P73 has a taller compression height(about .2mm IIRC). USDM ITR pistons have a smaller dome than both.
 
The more dome the piston is the higher the compression P30 still makes more compression. GSR swap with P30 pistons will make roughly 11:5 vs Jdm p73 11:3:1
 
Not to be offensive, but do you know how compression height affects compression?

Using a compression calculator that takes that into account, GSR with JDM ITR pistons is 11.59:1

Assuming the P73 have the same CH as P30 pistons(which they don't), then yes, you'd get 11.3:1
 
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Toe-May-Toe........Toe-Mah-Toe either way....stay below 12:1 and you can run 91 octane. Ask any shop and they will confirm....its all good. I want to do a similar build (but with my B16 head and a B18C1 bottom end) and I know ITR pistons is what I would go with. With Type r cams, I'm thinking somewhere around 185-195whp which ain't too bad in a EGg
 
Either way compression calculators are just to give you an idea on what kind of compression you are looking at but never exact figures. I use arias in most cases anyways. P30,P73 usdm/jdm,Pr3 are all good for daily driven swaps on 91 octane.
 
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