Official Headswap thread(Advanced Tech, no n00b questions)

[seth98esT]

Just thought about making one thread to gather all information...

I think that's splitting hairs. They may have different engine codes, but they are virtually the same. The 4gcs is a mitsubishi block, licensed to hyundai, and is actually a better choice for a 2.4L hybrid. This is because the deck is identical to the 4g63 head and requires no holes to be filled, and the 4gcs even has superior main bearing reinforcements.

Just browsin DSMTalk and found the 2.4L tuning thread and found that interesting.

Helpful Links:
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Link

Have questions, ideas, or anything that relates to the head swap, throw em out...

[JiP]

And he is right about the block the 4gcs is better to use, however..for lazy folk with little money i'll stick with my current block. The 5 holes I had a damn picture from a site of what the 1g head looks like on the 7g block, and you can clearly see why the holes need to be blocked off, the head pinches off only half the hole..the rest is open.

Now these holes are just drain holes, the only reason to block them is simply to prevent dirt and whatever little things from falling down the hole into your oil and getting it into parts down below. Theres a guy who did the headswap and simply put a square of sheet metal under the headgasket over those holes with a lil jbweld at the edges, the weight of the cyl head keeps things down good. And then theres the professoinal way of tapping the hole, inserting a plug.

BTW You also have to use a 1994 4g64 DOHC Galant GS head gasket, NOT the 1g or 2g 4g63 gaskets, our bores are larger, thats howe we get the extra .4l from the 2.0 model

OR for you junkyard savy folks...just go and find a 94 galant gs and pull the engine...its already DOHC 4g64.

[Dark Anghell]

Actually the bore is just about the same if not exactly the same, the stroke is what's different. On the 4g63 bore vs stroke ration is almost 1:1 which in theory is a perfect combination, especially for high-end power because the block is very stable. While on 4g64's that ratio might be 1:1.5 or something like that. Our engines are not very stable at high rpm becase of the huge amount of stroke we have.

So galants get that 2.4 motor by having larger stroke, and increased deck height over the 4g63 motor.

>One question that pops into my mind is this: Are the part numbers for pisons on 4g64 SOHC the same as part numbers for a DOHC for a 4g64 and 4g63 motors. If they are different, (which i think they are) the pistons would be another good thing to change when swaping for a DOHC.
>Why do i think that the part #'s are different? Because the CR on 4g64 DOHC is i think 10:1 vs 9.6:1 on a SOHC, so chances are...the dome of the piston is different. Now that i think about it for 4g63t they will be different for sure, because of 8.5:1 CR.
>Why is CR important? Because by raiseing CR on the car you can make more HP, that's how Galant GS came with 170 HP instead of 140 like all the other models. GS also had the DOHC engine.
>These are some of the questions i think about besides things like why is the sky so grey here in seattle, or why does it have to rain after I wash my car...

[JiP]

4g63 bore 3.34 inch
4g64 bore 3.41 inch

Not that bad but still better to use the 4g64 gasket, its something like 2mm difference, you still dont want the 2mm overhang from the 4g63 gasket.

As for the part numbers, according to CAPS they are different between the two models. They are even different for the 94 dohc depending what months the engine was made. However according to Chiltons chart which is the only reference in front of me right now other then CAPS, both models have 9.5:1 CR. But keep in mind that is with the original 4g64 dohc head. I dont know what the ratio would be using the 1g or 2g 4g63 head. I will ask the guys who did the swap if they know. But do you really think that with either head the compression is going to be much less then 9.5? I plan on going turbo anyway and from what i've read having too high compression wouldnt be the best thing for my situation.

[jiul]

Hey Pavel at what RPM level does the 2.4 become less stable and how much less stable?

[g96nt]

4g63 = 85mm bore... 88mm Stroke VERY close to being square.. and VERY stable @ high RPM.. limiting factor here is the head, which limits you to approx 8200RPM

4g64 = 86.5mm bore, and 100mm Stroke
very.. NOT square... as you can See, the stroke increases @ a Rate of 9:1
the 4g64 with factory rods/pistons are capable of a maximum repeatable RPM of Approximately 7950.... big/custom rods will help this "problem"


if you can.. get yourself a galant GS headgasket, if you're staying NA.
the DOHC does not change compression, it's the gs-specific pistons that do.

if you're looking to lower CR you may choose to pick up one of the thicker-than-stock cometic headgaskets. They're a little more $$, but still WAY less expensive Than replacing pistons/rings/rods

you could safely lower your CR to about 9:1 , or 9.125:1
which.. is safe for mild-boost applications.


and, yes Jip is correct, you will need to plug these holes.. they're simple-enough.. and hardly-noticable when done...

[g96nt]

are you saying I'm a n00b?

::angryface::

[seth98esT]

hah definitely not i just dont want anybody coming in here and asking stupid obvious n00b type like questions...plus i thought it would be cool cause DSMtalk has separate forums like advance talk haha im a poser

[JiP]

Ok Craig, what about people like Curt who turbod the 4g64, I dont think I remember reading on his site that he swapped pistons or anything on the bottom end. So he is still running 9.5:1 ratio of the stock 64 block. Doesnt he run 8-10psi?

Does that mean its ok to run moderate boost with the sohc head, but not with the dohc head with an engine that has the same CR? Only ask because you said it would be better to lower the CR to 9.

[Dark Anghell]

I think Curt has 9.5:1 CR on his spyder. It is better to lower your CR, this way you are to run higher boost levels. Correct me if i'm wrong, but if you have high CR and you are boosting, the head-gasket will not be able to handle so much boost, and eventually it will blow, and a lot of times when it blows it aslo bends the head.
That's why you hadly ever see Integra Type R's with turbos. They have very high CR, and that's how they make more HP.

From what I've heard/read 9.5:1 ratio is fine for turbo cars, as long as the pistons, rods, crank and the head itself can handle the boost. On 4g64's the crank is very strong, and does not need to be replaced. Aftermarket rods can be used from 4g63 because they are identical to ones used on '64. Pistons can be custom built and then have them ceramic coated, so that they can withstand more heat. For the head, a better headgasket will do the job, and maybe stronger bolts to hold it down.

Magnus motorsport offers 4g64 Hybrids in 9.0:1 and in 9.5:1 ratios.

[JiP]

Magnus has some pretty impressive stuff.

I was planning on using arp studs. There must be a difference between 1g and 2g head studs because they are different prices. So uh whats the difference and is the difference related to the block side or head side? Doing a 1g swap I would *assume* I need 1g headstuds(?)

[JiP]

For those who want to see a 2g get a 1g head installed...many of the things they do here we will have to do, and its chock full of pics of the engine block, belt area, heads, etc...

http://www.turbo4wd.com/HeadSwap1.htm

[Mazarin]

This summer scares me. It's either this of a GST 5-speed. I've been looking @ the head swap for quite a while now, and I still have yet to see 2 people do it the same...

...one of the reasons I'm leaning towards the GST 5-speed...

[JiP]

<div class='quotetop'>QUOTE(Mazarin)</div><div class='quotemain'>This summer scares me. It's either this of a GST 5-speed. I've been looking @ the head swap for Â*quite a while now, and I still have yet to see 2 people do it the same...

...one of the reasons I'm leaning towards the GST 5-speed...</div>

If I was able to pay the insurance id drop this galant in a heartbeat. But I cant buy a car and hold this galant while I wait to sell it and pay insurance on 2 cars, and I cant aford to not have a car so I cant sell it first and buy it. Plus I dont even have any money to buy ice cream. lol

I would just get the gst.

[seth98esT]

agreed...i think i wanna do the head swap first, then go 5spd, then go turbo haha im going to be sooooo poor...wait i already am poor

[g96nt]

maybe I was *too vague*

in ANY Case lower CR is better; Not that the SOHC can handle higher CR.. sorry


I'm fairly certain Curt has a Stock height headgasket, not a thicker one.

and no, 9.5:1 isn't So bad.. but there's not a lot of room for boost.
good news is... absolutely no turbo lag.

bad news is... well... you can't boost as much

[jiul]

I went the site that JIP posted for the 2 G swap, and I have two questions

1) Why was there a need to manufacture a "distributor block " for the MAP?
2) Why was there a need to drill & tap the intake camshaft?

(I hope that these questions are no too dumb for this thread.)

[JiP]

I went the site that JIP posted for the 2 G swap, and I have two questions

1) Why was there a need to manufacture a "distributor block " for the MAP?
2) Why was there a need to drill & tap the intake camshaft?

(I hope that these questions are no too dumb for this thread.)

Our intake manifold, and the 1g/2g/cyclone intake manifolds dont have a map sensor moutning hole on the intake. 97 galants dont have a map sensor, I forgot if its 97+ galants dont have them. But if you swap ecu's I think you may have to add the map sensor, which I THINK is connected to one of the intake hoses? I dont really know, so you need to fab something, or drill and tap your intake manifold to accept the sensor.

As for the camshaft I have no idea, I have in front of me both 1g and 2g cam sensors, though if you go to an autostore the 1g doesnt have a cam sensor they say..its like the crank sensor or something it actualy kinda does both signals. Anyway..They have the the piece at the end that slip into the intake cam shaft, there is nothing that has to be screwed into the shaft otherwise mitsu would have that hole already tapped in the shaft. He was probably fabbing his own sensor setup which I might do so I can keep my distributer cap, still wont have to tap the shaft though so dont worry about that.

[jiul]

Ok I get the part about having no hole for the map, but why the block? Is there a clearence issue?

Second about cam sensors, and this may really sound silly, but on a SOHC we have , obviously only one cam sensor.
On a DOHC are there two? ( I haven't bought the DOHC heads yet so I don't know)

[JiP]

<div class='quotetop'>QUOTE(jiul)</div><div class='quotemain'>Second Â*about cam sensors, and this may really sound silly, but on a SOHC we have , obviously only one cam sensor. Â*
On a DOHC are there two? </div>

Hey Seth does that fall under noob questions?!

1 Cam sensor on intake cam.