Need pistons for buildup

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T

Teambypass

Senior Member
REFFER TO MY SIGNATURE. since I already have everything that I need except valves, and I will take the head off and pay for a valve job I think I might as well upgrade my pistons, any recommandation for pistons and what I expect to pay for installation of pistons??? keep in mind, I dont dont know how to clay and do the pistons to wall or valve clearance(I think it just a matter of using a micrometter to do some measurements but I would rather leave that to the professional). any after market pistons that can be drop in without problem of pistons hitting the valves??? I want high compression, as high as it could get without pistons hitting valves. thanks
 
what stage skunk2's?

and honestly, i wouldn't bother with valves... too much work. thats a serious level of tuning, and the rest of your setup really won't warrnt its need.

claying is simple. you physically take motor clay, and place it on the pistons. bolt it all down, and hand turn the crank a couple rotations. take the head off, and see if your valves are hitting the pistons. lather, repeat if ddeisred.
 
With the skunk2 stage 2's if you are over 12.0 on your compression you will be ok. You don't have to worry about your valves hitting your pistons as long as everything is adjusted right. A good site for the how-to is c-speedracing.com, they give a demo of how to clay a motor. Its not the best but if you have some automotive background it does the job. You may also want to get a new fuel pump, and with that setup your stock ecu is not going to do the job. You will atleast need a vafc, but I recommend hondata, it owns.
 
well what are your goals? is this a street car? i think you need to do a little research ... "i want the highest compression possible w/o bending valves" are you sure?

i agree with the thought of not bothering with valves. unless you have a lavish goal, can pay a lot for tuning. but from the looks of it, your setup is pretty practical.

if you want to stay oem, p30 pistons are your best bet. in a gsr block with gsr head, the compression is 11.6 (according to c-speed). that should be ok for those cams, but from what i remember, they like somewhere around 12 (i don't know though). if that is true, maybe mill the head a little or get a thinner head gasket. personally, i wouldn't do either of these, as bending the valves becomes a little easier. if you're going to bump compression, do it with pistons. but that's just me, many have done it and are fine. it's your motor.

you could also consider pct pistons. c-speed says it will be ~12.1; however, there was some talk on ht about it actually being close 13:1. here's the link: http://www.honda-tech.com/zerothread?id=717928&page=1

P72 head/B18C Block: STD = 12.924594026551906 :eek:
i'd say that's a little high for a street driven car. unless you don't, paying $$$$$ for lots of tuning, and can live with a very tempermental motor.

some use them with out issue, some have the motors blow up after a few hundred miles. Omniman, someone who's experience and credibility i value highly, maintains that ctr pistons belong in ctr motors.

i'd go with the p30s, or maybe some aftermarket ones. do your homework first, this is nothing to take lightly.
 
To be honest. I dont have a good background about engine. As far as swapping honda motors, its easy for me now after my first swap. As far as taking motor apart, I can only take the head off and install the camshafts. These are what I know so far(of course, including timming belts, water pump and some basics), but last Friday, in my Engine service class, I just learned how to adjust valves and this new lesson could be a valuable in my buildup. TO ANSWER SOME OF YOUR QUESTIONS......My plan is to hit 13 flat to mild 13s. The car is a street car and will occasionally race on the track every now and then. The reason I want to buy skunk2 valves is because I think I might had bend some of the valves which lead to the low compression that I currently have. I just changed my oil about two weeks ago and now my oil dip registered half full so i think the valve seals might be bad too. Since I do not know how to replace valves, I will have the shop do it for me.Yes, these up grade are all skunk2 stuffs. WHHT IS A P30 PISTONS?? If i remember correctly, that's is a ctr piston right? As far as how much do I want to spend, I have two grands and all I have left is the valves since I already have the Skunk2 camshafts, springs, retainers, and a valve job is about $250. As far as how much do i want to spend for the pistons, since I am building up, I want to do it right and safe the first time, thats why I ask you guys which pistons have the highest compression without hitting the valves. If i can recall correctly from reading some of the posts in here, I remember they mention something about JEpistons that have high compression and the valve clearance is OEM specification. I know, TODA also have a set which is 11. something but they recommend to used with their stuffs. As far as replacing the pistions, how difficult is it? I have a haynes repair manual and a garage with some tools and an impact gun which made my job of taking hard bolts out easier. I am always confused about high compression, some people said ctr have higher compression but my intinct told me that itr have higher compression since it has higher rev. I know, city-speed sold a brand new set of JDM itr pistons for $100 something on ebay and they claim the compression is 11.1 they also have a ctr piston set for $200 something and they claim the compression to be like 12. something. As for the cost of these pistons, I am all for it even if it cost $500 but I nkow most after market pistons only cost $400 something. Only if the pistons are safe to used with my set up and do not hit the valves. another question, since I have after market springs, retainers, and camshafts, should I adjust the valve to OEM specification? For the safe side, I really like the ctr pistons since type r and GSR are almost the same, i think it should be safe to drop them in without worry about pistons hitting valves. please commas on these issues and give me your opinion on which pistons sets will be the best and safest to drop in without worry about piston hitting valves(beside the stock GSR pistons) I will check on some the sites that you guys provided. thanks for the helps and sorry for checking in so late since I went home over the weekend and have no access to the Net. thanks guys
 
jwn7, after reading that 3 pages thread iam more confused. I think 12.9xxxx and 13.xxx compression are too high for me. Maybe 12.1 would be nice. So, with all those variation of calcalating the compression, no fact and no actually number results. Ok, I think I can do the claying thing. So, do I lightly torgue every bolts or torgue them to OEM specification when I turn the crankshaft to rota the pistons? Do I do this to every pistons or just one? thanks
 
1. drop the wrench
2. burn haynes manual
3. get a helms manual www.helminc.com :worthy:
4. pick up wrench

p30 pistons came in the jdm b16. pr3 came in the usdm b16. pct is ctr, leave them alone if you don't want bent valves. i'd recommend p30 pistons. 11.6 is a good cr, you can make good power at that level. also if you're shooting for 13's, you should be able to at that cr.

i wouldn't bother with the skunk valves, but it's your head. make sure you clay the motor, and have a very good tuner there. also make sure you're familiar with proper break in techniques.
 
Thanks man. how is a Helms manual differ from Haynes mannual? is the Helms manual better in instructions and diagrams? What brand or company sell P30 pistons(I'll check on c-speed if they have a set)? how much is a good price? What is the proper technique after rebuild these parts to my car? how many miles is the proper break in period? Im just curriouse, why is that averyone oppose using skunk2 valves, is it because its bad? I won't need them, but since I think my valves are bended and bad, I need to replace them(i got them as a set). how is OEM valves differ from skunk2?
 
If anyone could tell me what is the part # for the p30 pistons that would be great! thanks
 
P30 is Honda's part number. It's an OEM piston. Order them from your local dealer's parts department, or try to find a set on eBay.

The Helms manual is better than the Haynes because it's the official Honda service manual. Honda uses Helms manuals in their dealerships, and Honda provided all the correct technical information to Helms when they printed the manuals.
 
p30 pistons are jdm, so i doubt you can just go to the dealer and get them. if you can, this is excellent news for me, but i was under the assumption that you can't get jdm exclusive parts at usdm dealers. am i wrong?

helms manual >>>>> haynes manual. it's the bible for your car. get it now, it will be the best $70 you can spend. haynes manuals suck in general, and they have wrong torque specs (i know all about that ... :angry: ).

oversized valves are harder to tune. there's nothing wrong with them, you may get some more power, but tuning is a bitch. not to mention your valve to valve clearnaces will be less, thus you may end up bending them easier. but you'll probably be fine. get them if you want, but make sure you read up first.

there's many ways to break in. this is a good one, taken from rocket.

Originally posted by Rocket
Have

1) proper oil level
2) PepBoys 10w30 or ND30
3) proper coolant level. Honda Coolant or similar silicate free shit. (use distilled water. Avoid using tap water).
4) proper tranny oil level
5) proper valve lash 0.007/0.009 in/ex are magical numbers for BVTEC cams

"Pre" Break In

1) pull spark plugs and take jnjectors clips off injectors (engine cranks faster without spark plugs)
2) crank until oil pressure light goes off
3) then crank 30 secs more to get all bubbles and stuff out of the oiling system
4) re-install plugs and injector clips
5) start motor and check ignitinon timing (16 deg. is good)
6) warm up by idling car at 1800-2000 rpms for 3-5 mins
7) let idle and verifty ignition timing.
8) shut off engine and change oil and filter

Break in

1) warm up again by driving around
2) get on the son of a bitch listening for knocking or smoke etc.

Note: Use your senses and just be cautious.
Click to expand...


this is another good read: http://www.mototuneusa.com/break_in_secrets.htm
and another: http://www.importbuilders.com/breakin.html

NO SYNTHETIC DURING BREAK IN!!!!!!!!!!!!!! a friend thought he'd be cool and try it, and his motor ran like ass, and blew up in 300 miles. it's also very much advisable to have a wideband o2 hooked up, so you don't run lean. if you can, start the motor up on a dyno.
 
Originally posted by jwn7@Mar 9 2004, 07:15 PM
p30 pistons are jdm, so i doubt you can just go to the dealer and get them. if you can, this is excellent news for me, but i was under the assumption that you can't get jdm exclusive parts at usdm dealers. am i wrong?
Click to expand...

Some dealers DO allow you to order JDM only parts from them... :D :D :D

I don't know who might in your area, but just ask around- some of them do order JDM parts.
 
Thanks for the break-in info.
I found some ctr on ebay. The guy said he could get oversized like, .020 and .040. should I go for standard size or oversize? I didnt honed my cylinder.
 
Get your cylinders honed, and new oem piston rings. They will help keep all that new found compression you are looking for out of the crankcase, and keep oil out of the combustion chamber. It will save you head ache in the short and long run. Check out wiseco pistons too. They make lots of different compression ratio pistons to choose from. Go with oversized pistons if you want a little more displacement, higher cr will also result from oversizing the pistons, since you will be sucking in more air, and squeezing back into the OEM combustion chamber. Calesta is the man to talk to when talking about oversizing and CR. Anyone with a mechanical engineering degree, and also blows up expensive motors at the drop of a hat is okay in my book!!!

PS. I don't know if I would pull off the spark plugsa and just start cranking to break in the motor. You could end up sucking stuff into the cylinders and boogering up the valve seats. Just my .02 LSVtec on this site addressed the break-in procedures he used somewhere on the site. Talk to him about it.
 
Originally posted by Teambypass@Mar 10 2004, 11:42 AM
I found some ctr on ebay. The guy said he could get oversized like, .020 and .040. should I go for standard size or oversize? I didnt honed my cylinder.
Click to expand...

first off, ebay sucks. buyer beware. :ph34r:

you should hone your cylinders for sure - it be really really stupid not to.

in my opinion, ctr pistons in a non ctr motor are very questionable, and can be dangerious. make sure you want to do that before you buy, which means being fully aware of what happens, and how to prevent it. p30 pistons are much much safer, and you can still make great power at 11.6. that 0.4 won't make much of a difference, and i don't think it's worth the risk at all. anything above 11.0 is respectable; 11.6 is a real nice, safe, easy to tune, and full of potential.

it seems like you're really rushing into this. slow down .. before you make a different mistake. engine building is just as complicated as chassis prep. here's a good link to show you what you're getting into: http://www.theoldone.com/articles/badtothebone/ :eek:

take your time and do your research before you buy. ;)
 
Thanks once again guys. I really appreciate your knowlegeable skills and advices. My car is running really bad due to low compression such as I stated above, 120 and 130. I still have my old motor which only has 74K and that will be going back to the body and the B18C GSR will be out for those new parts this spring break March 14-20. All that is left are the pistons and I will keep looking for it. I will also check Weisco to see what they got. Another unclear guestion is that, if i check my cylinder wall clearing and if its up to OEM specification, do I still need to hone and get oversized pistons and rings? If so, what oversize(i guess, this depend to how much the cylinder is honed). Another guestion is that, after install all these, I would have to adjust the valves for clearance, do I stay to OEM specification or adjusted to meet the need of those new parts? thanks
 
I forgot to ask something. In my Engine service class, they mention that you only honed the cylinder wall due to "ring ridge" which the cylinder wall is crapped up and not round(egg, oval shap) then honing the cylinder wall is necessary. It would be nice to hone the cylinder wall and get oversize pistons since this will such more air and raise compression, but I doing these sound too complicated, I just want to drop the new pistons in without honing<<<<<would this be ok? could someone explain more in deep into what is the pro of honning the cylider wall? thanks
 
Honing helps provide a good ring seal for your new rings and pistons. Get it done, its no big deal. You only need to go oversized if you have some damage to your cylinder walls.
 
if you don't feel comforable honing it yourself, bring your pistsons, rings, and your block to an auto machine shop. Either way, do it. old rings will wear the walls even a little bit, and will not be the name as new rings.

as for p30- remember there are two types.

the usdm pistons will yield about .4 LESS compression then the jdm counterparts.
bill bought his set for $100, and bought oem honda rings from the dealer

however, i wouldn't recommend the p30's. they won't fit the stock gsr rods. ls/b16 share a rod shape, gsr/ctr/itr share a rod shape. putting A piston on B rod, and vice versa, will result in undesirable results.

ctr's or itrs if you want a little less, will be your best bet if you want to stick with oem. but, you're not going to get ctrs or itrs for $100 bucks either.
At this point, i'd say, just go ahead and go aftermarket.

Not only will you be able to exactly select the compression you want, they will come with new rings and wrist pins.

i'd recommend the PR07 IB spec probes:
http://store.ibspec.com/pistons-ib-spec-probe-b-series.html

http://store.ibspec.com/pr07.html
 
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