cp or wiseco stock compression pistons?

[duh2150]

Well, i fail to find some stock compression pistons for the 4g64, only thing i can accually find is 4g64 with the 4g63 head, with like compression of 8.5:1 im pretty sure they are talking about the evo 4g63 head, im putting on the kia head but that would drop me to like 7.5:1 compression, my question is do they even make reg stock 4g64 pistons?, and there custom order thing is confusing as hell! lol, can anyone give me any info?

[peanotation]

if you really want stock compression, JE will build any custom piston you want for a roughly flat fee of ~$650. but here's my question...why do you want stock compression? either you want something a little low for big boost...or something higher than stock for some n/a tuneage action. what are your plans for this?

when you swap on the kia head...pics or ban! :)

[duh2150]

lol because i need stock on stock pistons and kia head it drops the compression to 8.5:1 and its perfect for turbo, thats why im looknig for stock compression if i get 8.5 for the engine the head would make it 7.5:1 or so lol so ill look up JE and see what and how they find out, but i really dont know the specs of the pistons of the stock ones wiseco and cp wanted all kidna of crap, and i only like know the cc on the head is 57 lol

maby i can ask them for the 4g64 with 4g63 head but wit ha 57cc head and i need 8.5:1 C/R, maby it would be easyer for them to understand that?

what i got so far:

JAM Valve Locks
JAM Bronze Intake and Exhaust Guides
JAM Valve Seals
Brian Crower Nitride Coated 1mm+ Valves
Brian Crower Titanium Retainers
Brian Crower Valve Springs

other crap i need for the head is Brian Crower 272 cams and Fidanza Cam gears i got a long way to go, ill have pics of the head when i get it machined

[peanotation]

maby i can ask them for the 4g64 with 4g63 head but wit ha 57cc head and i need 8.5:1 C/R, maby it would be easyer for them to understand that?

that's a listing name that wiseco uses, JE may or may not know what you're talking about. when it came to this point during my motor build i let the engine shop guy do all the figuring because at this stage of the game you better know precisely what you're doing otherwise bad things will come.... it sounds like this is your first time doing this, i would recommend you spend the couple extra hundred bucks and have a trusted machine shop guy step in.

[duh2150]

yup my first time doing this lol, yeah i might get the rods and tell the machine dude just to finish it lol, and i could swap the head on myself, it would be easy if i was keeping the head stock, but this is like a hybrid between like 4 differnt cars, eclipse, kia, evo, and galant lol, it gets very complicated sigh ..

[duh2150]

only pistons wiseco hasare are similar would be

bore of 86.5mm
for a 47cc head
9.7 C/R (would drop me down to like 8.7) i think
and 22mm pin

maby they would work?

also a 87mm bore
but with 9.0 - 9.3 C/R

[duh2150]

no one else has any opinions? or comments?

[DOHCstunr]

Wiseco's are going to be the most daily driven, short trip friendly piston you can buy other than oem.

Their alloy is designed not to expand much once at operating temperature. this allows for tighter clearances, and no piston slap at cold startup.

[duh2150]

thanks, lol thats some good info, do you got any info on the pistons they sell?, becasue of the dohc swap im gonig to be doing..?

[duh2150]

humm wow usually peoples know alot about this on here

[WarmAndSCSI]

Never have had piston slap with CP 2618 alloy pistons... cylinder wall-to-piston clearance is 0.0035"

You'd be fine with most any properly-designed 2618 piston.

[duh2150]

but my most problem right now is finding the right pistons to drop in..

[WarmAndSCSI]

Aaron, you're clearly not listening to the advice that has been given to you. To get the exact compression ratio you desire, you're probably going to need to call up a retailer for Wiseco, CP Pistons, or whoever and ask them to have a piston custom-engineered for you. That, or you can calculate the effective compression ratio if you were to use any readily-available piston given the combustion chamber volume, deck to piston top clearance, piston dish volume, and head gasket thickness. This isn't stuff you're going to have spoonfed to you. You need to do these calculations yourself.

[duh2150]

yeah i figured that, i didnt know if anyone acculy found a stock compression piston thats what i was asking lol, i should jsut cal lthem up and make me a stock one for my galant with same compression, they should know..?

[xd_01]

i had the same problem sourcing some 2.4/evo hybrid pistons from wiseco too. the ones they do have listed are for 2nd gen 4g63 motor which can be used but the piston has to be installed backwards becuase the wrist pin offset is on the wrong side and the valve reliefs have to be machined bigger in most cases. wiseco also sells most there pistons in stock compression for the evo,1st,2nd gen motors but you can customize them if you want.

i got lucky and found somebody selling their custom pistons and snatched them up. i believe CP and Ross sell pistons spefically for the 2.4/evo swap but i prefer Wiseco for a street car.

if you call Road Race, AMS, Magnus or any of those guys they will custom spec pistons for you, that would the smartest thing you can do, bad thing thing is turn around time is like 3-4 months

[Stewi]

lol because i need stock on stock pistons and kia head it drops the compression to 8.5:1 and its perfect for turbo, thats why im looknig for stock compression if i get 8.5 for the engine the head would make it 7.5:1 or so lol so ill look up JE and see what and how they find out, but i really dont know the specs of the pistons of the stock ones wiseco and cp wanted all kidna of crap, and i only like know the cc on the head is 57 lol

maby i can ask them for the 4g64 with 4g63 head but wit ha 57cc head and i need 8.5:1 C/R, maby it would be easyer for them to understand that?

what i got so far:

JAM Valve Locks
JAM Bronze Intake and Exhaust Guides
JAM Valve Seals
Brian Crower Nitride Coated 1mm+ Valves
Brian Crower Titanium Retainers
Brian Crower Valve Springs

other crap i need for the head is Brian Crower 272 cams and Fidanza Cam gears i got a long way to go, ill have pics of the head when i get it machined

just a piece of advice on the parts you bought. I dont want to scare you, but for the future, stuff like valves and guides and what not, you really dont want to buy until a machinist looks at the head that your having built. The reason being is that not all heads are the same, there are tolerances that vary slightly. Perfect example and you can ask XD01 he will confirm it, he wanted to go +1mm valves on the intake and exhaust side and he COULDNT because there wasnt enough clearance on the exhaust side, so he had to go .5mm on the exhaust side. Its just like doing a block, let the machinist look at the part and tell you what you need and spec it out, so you dont waste money buying the wrong shit.

[duh2150]

yeah stewi, i know underated has 1mm over on both sides, so it should be possible

xd_01 did you do the evo swap or the kia swap, technically i need 2.4/kia pistons, or just reg 2.4l galant ones, the ones for the evo are less compression because there head cc's are smaller, if i were to put them in my engine with the head (kia) it would be like 7.5:1, ill call AMS and them guys having the kia head throws all the compressions you see like -1

accualy i think the compression would be like 5:1 lol because the evo head boosts compression and if they lower it down to 8.5 on a 4g64, wit hthe kia head it would be like 4.5:1 or somthing strange like that, maby im a bit mistaken, or thinking to hard

[WarmAndSCSI]

Didn't I waste my time calculating this for you one time and I found it was going to be like 7.6:1 compression!? Good God, you're hopeless.

[Stewi]

yeah stewi, i know underated has 1mm over on both sides, so it should be possible

You dont understand what im saying. What im saying is that there are differences in tolerances of EACH INDIVIDUAL CYLINDER HEAD.

XD01 has an EVO8 head, I also have an EVO8 head, I have +1mm intake and exhaust, it fit, he has +1 intake +.5 exhaust, because +1mm on the exhaust side didnt fit. The same person built our motors, a very very reputable local engine shop that does 75% mitsu.

[duh2150]

oh i get you stewi

yeah warm 7.5:1 is like if i destroked it, its 8.5:1 with stock pistons with kia head, 11.5:1 with stock pistons and evo head
with kia pistons everything is like 1 C/R higher

wiseco makes 2 different C/R models but its for the evo 8 head not a kia, so it throws all the things off, what i been trying ot find out is if any of these companys made a 9.5:1 C/R pistons for a sohc 4g64, (or like 11:1? 4g64 with 4g63 head pistons? becasue the differnt in drop would be like 2 C/R becuase ill be putting them on a kai with a 56cc head not a 47cc like the evo 8 head)

does anyone get what im trying to say?