Kia head vs. Evo head?

[jlfisher360]

Ive searched around for some tips, but I cant seem to find an answer to this question. Which DOHC swap would give better HP, a Kia head swap or an Evo head swap?

[GOOSEY2099]

Kia has a 56cc combustion chamber, and evo has a 43cc. So with kia you'll need custom pistons to get the right compression that you desire.

[platano]

^so basicaly, what you're saying is that the Evo head is simpler to do the swap in the sense that you are not forced to have to buy '"custom pistons" if you dont desire to do so. correct?

and the evo head being 43cc is already the ideal option?

[lonestar22]

well you dont HAVE to buy custom pistons, but it doesnt hurt if u plan on making gobs of power

[platano]

true, but you can still make "gobs of power" with the stock OEM evo pistons. And money can be better spent on actual power adders like cams, fuel injectors, TB, etc.

[GOOSEY2099]

You are gonna need custom pistons wither way. You can't use stock evo one because they are smaller, but you won't need to make custom custom ones either.

[GOOSEY2099]

evo is 85.5 bore, galant is 86.5mm bore. And you'd need to go .020" over to cleanup the cyl walls anyway. so you need new pistons to be 87mm. Now when you order pistons for the evo head you can actually pick out an evo part number and tell them you need them in 87mm diameter. But with HY/KIA heads you will need to figure out the dish size, valve pockets, stroke, compression and hope thats exactly what you'll get. Basicly to get the evo one it will be at least $125 cheaper.

[blue8g]

if you run the kia/hyundai head you'll be at 8/9:1 compression evo head will be like 11:1, if i remember right....

[platano]

Goosey, i realized where you were going with your initial post. so i deleted my post prior to reading your latest one. but yeah, continue on w/ the thread..

[blue8g]

i think you can run stock pistons, they'll just have messed compression, right???

[ZigenScarface]

i dont think with just a head swap your going to have GOBS OF POWER either way.. try boosting ur car insted

[platano]

i dont think with just a head swap your going to have GOBS OF POWER either way.. try boosting ur car insted

uh.....dude......that kinda' goes without saying. we are just talking about the actual Head swaps here. not the entire engine build.

[blue8g]

what parts besides the head are necessary for the swap??

NEVERMIND FIGURED IT OUT

[jlfisher360]

Im trying to search some salvage yards around my house here in NC. What year would the evo have to be in order to fit?

[blue8g]

i think it just has to be any evo VIII right???

[jlfisher360]

Thats what im thinking cause just about everyone on here and club 3g says evo 8, but once in a while someone says evo 6s and 7s. And I looked on ebay and found a kia head for about 399, but cant seem to find any evo heads cept through google, and theyre about 1299. Im still gonna go with the Evo head though because it seems to me like you get more for your money outta the evo head than the kia head.

[blue8g]

i plan on using the kia head....

[Stewi]

Any EVO 8 head will work. The JDM EVO 4-7 heads will fit too, but you would need all their other BS too, intake mani (I think its different) thermostat housing, water pipe, etc I know those are different.

[GOOSEY2099]

basicly this info has been discussed way tooo many times. Please search club3g if you want to know EEverything

[Boosted]

Thats what im thinking cause just about everyone on here and club 3g says evo 8, but once in a while someone says evo 6s and 7s. And I looked on ebay and found a kia head for about 399, but cant seem to find any evo heads cept through google, and theyre about 1299. Im still gonna go with the Evo head though because it seems to me like you get more for your money outta the evo head than the kia head.

The Optima/Sonata head can run as low as $200 through www.car-part.com (http://www.car-part.com). Evo heads are good, but the Sonata can build as much power IMO. Just look at the Sonata-powered Evo 9 on www.toplevelperformance.net (http://www.toplevelperformance.net).

[ZigenScarface]

shut up planto

[blue8g]

dude what's wrong with you lately???

[Stewi]

The Optima/Sonata head can run as low as $200 through www.car-part.com (http://www.car-part.com). Evo heads are good, but the Sonata can build as much power IMO. Just look at the Sonata-powered Evo 9 on www.toplevelperformance.net (http://www.toplevelperformance.net).

I know the owner of that car pretty well, your also talking about that motor having $5-6,000 worth of work into it. Its not a matter of building power, its a matter of investing the money in the right parts to be able to do it RIGHT.

[jlfisher360]

Read this on another forum:


desertsoldier22
May 11 2005, 07:29 AM Post #2
Group: Members
Posts: 11
Joined: 11-May 05
Member No.: 9,762
Status:
Location: Camp Humphreys, Korea
Drives: 2002 Eclipse GT



Heres the problem, the 4g63 was specifically designed to be a turbo motor the 4g64 was not. The 4g63 has Forged Pistons, billet aluminum rods and a better machined crank with better main bearings and rod bearings, almost every accessory on the engine has been beefed up, a 4g64 does not. A 4g64 also has higher compression ratio than the "63"
so an uprade of the fuel system is a must and you'll have to use premium fuel. However the heads do fit and you can get a custom head gasket made, but the 4g63 turbo manifolds will fit on the 4g64 cylinder head so replacing the head is not needed.

So do you get the same gain if you just swap the manifold rather than swapping the whole head?

[Boosted]

I know the owner of that car pretty well, your also talking about that motor having $5-6,000 worth of work into it. Its not a matter of building power, its a matter of investing the money in the right parts to be able to do it RIGHT.

You would have to do the same with an Evo head to build that power too. Power isn't built on cheap ass Ebay company produced parts like Tsudo, Kamikaze, OBX, etc.

[Stewi]

You would have to do the same with an Evo head to build that power too. Power isn't built on cheap ass Ebay company produced parts like Tsudo, Kamikaze, OBX, etc.

I made 370whp on a stock EVO head with stock cams, purely stock top end. There are a ton of guys on EVOM running 400+whp on stock motors and just a set of cams and a turbo upgrade. ZEESHAN from club3g made 400whp on a junkyard stock 4G64 SOHC motor and the motor lived for over a year with him beating the snot out of it.

Everyone needs to really consider what their going to do with the car before buying parts. Knowing what I know now, if I only wanted to make 350whp or so, I would have left the stock SOHC motor in the car, swapped to a MLS headgasket and headstuds, a good turbo setup, injectors/pump and a good engine management system.

So with that being said, there is no right or wrong answer until the person in question thoroughly considers their goals and intentions for the car.

And regarding ebay parts...I know that. I just spent $4k on a new tranny setup and $1500 on a new turbo manifold and downpipe. When your trying to do everything perfect, you will dump alot of money into it. Again knowing what I know now, I would have started off with an 8g that was dented up and a blown motor, that would have been a much better starting point for me.

[Stewi]

Read this on another forum:


desertsoldier22
May 11 2005, 07:29 AM Post #2
Group: Members
Posts: 11
Joined: 11-May 05
Member No.: 9,762
Status:
Location: Camp Humphreys, Korea
Drives: 2002 Eclipse GT



Heres the problem, the 4g63 was specifically designed to be a turbo motor the 4g64 was not. The 4g63 has Forged Pistons, billet aluminum rods and a better machined crank with better main bearings and rod bearings, almost every accessory on the engine has been beefed up, a 4g64 does not. A 4g64 also has higher compression ratio than the "63"
so an uprade of the fuel system is a must and you'll have to use premium fuel. However the heads do fit and you can get a custom head gasket made, but the 4g63 turbo manifolds will fit on the 4g64 cylinder head so replacing the head is not needed.

So do you get the same gain if you just swap the manifold rather than swapping the whole head?

this guy is an ass-hat. The reason to do the DOHC headswap is for greater power potential as the motor is more efficient. It also opens the doors for more readily available performance parts like cams, which are designed for an EVO.

The 4G63 does not have aluminum rods from the factory, in face the EVO rods are the same part# as the 4G64 rods, same exact rod. The EVO crank isnt even nitride coated, neither is the 4G64 crank, so nobody can say one is weaker or better machined, tolerances are tolerances, they machine it to within spec and thats it. When I built my EVO motor I actually used a 2g DSM 7 bolt crank because it comes from the factory nitride hardened and the EVO's dont.

Just be careful who's advice you take regarding performance mods. There are many people here and on club3g that know whats up. I gave up on taking advice from the V6 eclipse guys because they always "talk down" to me because I dont have a V6, so pretty much they hate.

[jlfisher360]

+1, Well said.

[blue8g]

nice post!

[Scout4g64t]

im making over 300whp turbo on ALL STOCK MOTOR How long will it last.. who knows ive been boosted for over a year and I boosted my car with 120k on it. I have a some namebrand parts and then some no name brand stuff. I think its all about the install THE TUNING!!!! and being realistic.. people will tell you a million different things about no do this do that and at the end of the day they have not done anything major to their cars. I say set a plan and execute.. your driving your car not anybody else. if it sucks hey at least u did it, experienced it and drove it.. i see guys with boosted g's pushing crazy psi and still dont make the power my shitty stock G makes..

[4g64turbo]

for what i can see 90% is in THE TUNING!!!!

[GOOSEY2099]

I been boosted for a long time now. Tunned at 11.3afr with 18psi. I drive the car hard all the time and i get 20mpg while still beating the shit out of it. In the end it all comes down to finding boost leaks and tunning. Of cource you should never neglect your engine management platform. SAFC 1/2, f-conn, emanage are all very useless parts as they'll never be able to control the engine the way a normal ecu would. A good tunner is a must. Not the one that would put you right on a dyno, charge $400, spend 1 hour and call it tits (Like Sean Ivey). Honostly with everything i've tried to do to my Original engine, i wouldn't recommend anyone doing the headswap unless you are really sure you want to turbo it and try to make 350+whp.