thinking pistons 2.4dohc

**XXL4G64** · 07-02-2010, 10:28 AM

Was going on y'all today i was stopping around for pistons for the dohc 2.4 setup and i found something i didn't really think of this but evo9's piston's but i have Eagle H-Beam 's rod's. What would make u feel better about your bottom end if u was looking for piston's.

**skrap** · 07-02-2010, 04:34 PM

Dude please take your time and use grammar!!!

**XXL4G64** · 07-02-2010, 05:12 PM

Ok! Do u think that evo9 pistons are cheaper and will work just as good as other aftermarket one's.

**Galanttuner10** · 07-02-2010, 05:38 PM

aftermarket rods need aftermarket pistons. please remember the pistons from the evo are NOT the same size, they are smaller. save up and get manley or wiseco pistons.

**XXL4G64** · 07-02-2010, 08:39 PM

yea i know but what im saying is do they work if they 15% lighter than oem 2g's i think if i read right on here : http://www.thedsmgraveyard.com/product_p/n1110b076.htm

**troubled4g64t** · 07-02-2010, 08:55 PM

Look what they are saying is that the 4g64 has 86.5mm pistons the evo or 4g63 has 85mm therefor do not fit in our block what you would need to do is decide which head you are going to use since the evo head increases c/r and the kia head decreases the c/r then find the best piston to put your motor in the range you want.

**skrap** · 07-04-2010, 02:04 PM

If you are using the 64 block you will not be able to use Evo pistons.. just like how you cant used eclipse pistons. The pistons for the 63 motor are wayy too small to fit into our block.. What you can to if you want to increase your strength is get some aftermarket 64 pistons and you can use Evo rods.. They are lighter and ALOT stronger! I hope that answered your questions. I have a tough time answering questions for you because you run everything together are it doesn't make any sense. It gets frustrating so please from now on just take your time and type out your questions properly and make proper sentences please.
Thanks

**XXL4G64** · 07-05-2010, 04:17 PM

Yeap. plus im going for a 87mm pistons and the bad part is trying to find a better turbo.

**Gtorque** · 07-05-2010, 06:29 PM

go for some 86.5 CP pistons (standard).thats what im running on mine.once the blocks homed out and cleaned for these pistons you will have your 87mm.(lol just learned this).i have these pistons on eagle rods and car ran great

**Stewi** · 07-05-2010, 07:45 PM

Originally Posted by Gtorque

go for some 86.5 CP pistons (standard).thats what im running on mine.once the blocks homed out and cleaned for these pistons you will have your 87mm.(lol just learned this).i have these pistons on eagle rods and car ran great

What I was trying to tell you in the PM is you CANT DO THAT. If your final bore is 87mm, your piston must be the same size, you dont order the piston a half millimeter smaller than the bore. Thats also why I said to bring your pistons to the machine shop so they can match the bores right. Tolerances in engine building are checked down to .0001 Thats one ten thousandth of an inch. So lets say you have 3 pistons that are dead nuts 87mm which is 3.4252" and then one piston is 3.4261. Your not going to bore all 4 cylinders the same bore if one piston is .0009 larger than the other 3. Look for pics of engines in process of being assembled, you will see the shop numbers each piston and rod, thats because each one is fit to its own cylinder, its own wrist pin and its own crank journal, it needs to be done like this because its the RIGHT way. If not it will fail.

**XXL4G64** · 07-06-2010, 11:05 AM

If i run 8:5:1 with a (Turbonetics) T04B do u think that i will have little more tq than a stock evo 8. Im sorry to ask.

**evil-G-nius** · 07-06-2010, 12:00 PM

how much boost are you going to run. you could have that setup and be nowhere near the stock power and torque of an Evo. Not to be mean, but looking at your questions and what you are trying to do....it doesnt sound like you understand enough about the project. It might be safer to do more research before you try to boost the car....you'll have your engine longer...idk, just my opinion after reading this whole thing

**skrap** · 07-06-2010, 01:33 PM

^ agree 100% !!!!

**XXL4G64** · 07-07-2010, 03:57 PM

LOL yeah ok. but I'm be running about 15psi daily driver and track 31 psi. A lot of people told me that 31 psi is pushing it. With out the right type of tuning i have blueprint my project more than 10 times over the last to years and read a lot of your post here only thing that hold me back is money.

**skrap** · 07-07-2010, 04:10 PM

If the only thnig that was holding you back is money then you wouldnt be asking questions like this.... If you knew soo much about your motor then you would know that the bores are completely different....

**allrice4g64** · 07-07-2010, 06:52 PM

ya just run 31 psi on the stock suspension and stock wheel do what i do your better off entering a burnout contest, unless your interested in lsd diff built tranny built motor built everything. im running 12 psi daily on a flawless tune and have a 273 daily driver stock bottom end stock sohc head 14b with 450s. u dont need to spend money to make power u need spend time.

**Galant306m** · 07-08-2010, 02:03 AM

Originally Posted by Stewi

What I was trying to tell you in the PM is you CANT DO THAT. If your final bore is 87mm, your piston must be the same size, you dont order the piston a half millimeter smaller than the bore. Thats also why I said to bring your pistons to the machine shop so they can match the bores right. Tolerances in engine building are checked down to .0001 Thats one ten thousandth of an inch. So lets say you have 3 pistons that are dead nuts 87mm which is 3.4252" and then one piston is 3.4261. Your not going to bore all 4 cylinders the same bore if one piston is .0009 larger than the other 3. Look for pics of engines in process of being assembled, you will see the shop numbers each piston and rod, thats because each one is fit to its own cylinder, its own wrist pin and its own crank journal, it needs to be done like this because its the RIGHT way. If not it will fail.

Im not trying to start a argument but i feel this is kinda on the false side, the diameter of the piston could be off more then .001" and the engine would be fine im pretty sure even if they where like .010 of you would still be fine. Im just saying this because you gap your rings to fit the bore and all the ring gaps are like .015-.030 and the rings are there to keep everything moving smoothly, the piston dia is critical but to a point. Yes 4g63 pistons will not work in a 64 block and no you are not going to end up hoaning out 1mm of material, at most when hoaning you will take out a few thousandth's and that's about it, if you bore the cylinder out then yes you can take out as much as you please and match them to the rings that you gaped for the piston that is going in.

Brian if i read what you where saying wrong im sorry i know you know your shit.

**Galant306m** · 07-08-2010, 02:15 AM