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4g63 to 4g64 swap

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Well... My pistons arrived and to my surprise they will not work properly. These pistons are made for 2000-2005 4g64 blocks ONLY apparently. I called CP and they said to call Race Engineering that the pistons were a custom design for them as a reseller. I called Race Engineering and the guy informed me in 2000 the block was shorter than in 1999 and prior years. :(

I told him Hollander said the 99-03 blocks were the same and well I guess that's not totally true.

I was told I could use the pistons but the compression ratio would be really low. I held the pistons up side by side with my OEM pistons that I pulled from the block and the CP pistons are quite a bit shorter, AND they don't have valve reliefs... which is what had me questioning this to the begin with. WTF!

So I guess I have no choice but to sell them and get my money back and buy a set of Wiseco 87mm.

Such a total bummer :(
 
I'm not sure I follow... were the pistons designed for a longer rod?
How much shorter are they? Are they by chance... say... 6mm shorter? :)
I don't know why you'd expect valve reliefs, the stock pistons don't have them and they're 9:1 CR.
Also, I'm sure you know, but stock bore is 86.5mm and to use an 87mm piston you'd have to overbore the cylinders 0.020".

We need some measurements, specifically the compression height, or at least the height from the bottom or top of the wrist pin bore to the piston crown on both OEM and the new CP pistons. And the dish/dome cc's if you can.
 
You haven't been reading my thread have you? Yes, I know they are .020 over and I've mentioned several times that the block is going to the shop to be cut to match the pistons.

The CP pistons I bought are for a 2000+ 4g64 block in a "3G spyder eclipse" according to Race Engineering, where the pistons came from. He told me that the block height up to 1999 is TALLER than the block height from 2000-current.

The guy at RE told me that I can use the pistons but I'd have a compression ratio of about 7.5-7.8 which is way too low... I just took some pictures comparing the 2000 4g64 CP pistons to the 99 4g64 OEM pistons, I'll post them in a few minutes after I transfer them from my phone.

Quote from RE: "1/4" height difference in pistons from 99 to 2000.... 2000+ blocks are 9" +/- .020-.030""
 
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Yes, I have read the thread. I was sure you knew, but thought you may have momentarily forgotten and deduced the pistons were incorrect by them not fitting in the bore. I was not trying to imply anything else.

I'm sorry if I've misled you, I was genuinely not aware until now that there was a difference in the deck height. I'm sure now that you've noted it here, there will be several people who say "I told you so" even though they made no reference to deck height before. However, you might still be able to use the pistons.

The engine will need to be decked anyway, you could always take a little extra material and you can always use a thinner headgasket as well. What thickness HG was RE assuming when they designed those pistons? With an 87mm bore, for every 0.2 of a milimeter the HG thickness decreases, the CR will increase a tenth or two. Another option is once again to use longer rods, if RE designed them to be used with a thin (<1mm compressed) HG, you could increase rod length a couple or three millimeters and then use a thicker HG than they used in designing the piston CR to offset the rod length increase.

Looking at the pictures, I see what you mean about the valve reliefs. The flat-top design also concerns me. It looks to me as though those were meant to only be used with the 3G's head. Not sure what you asked for when you ordered them, but if they knew that you were going to use a different head, it seems to me that you'd have enough reason for them to be forced to take them back and give you another set.
 
the only real specs I know for a fact of the CP pistons is this:

1.200" Compression Height
.0035 Piston/wall clearance

I'm going to get rid of these pistons. I listed them, with the rods, and my polished 100mm crank on ebay.

I'm going to buy a set of Wisecos... Atleast I know for a fact using the wiseco pistons I won't have to mess with any of the other shit.
 
do you guys know the difference between the 1994 DOHC 4G64 and the 1994-1998 SOHC and DOHC motors besides the heads, the 4G64 i'm looking at looks just like my 6-bolt motor. wondering if theres a differance between bottom ends?
 
From my research the 4g64 blocks are the same from 93-98 Galant, and 95-99 Eclipse. The DOHC 4g64 only came out for 1 year in the 94 Galant GS, but like I said, the blocks should all be the same in those all of those years.
 
From my research the blocks are the same from 93-99 on the 4g64. The only difference on the Galant DOHC was just the head.

thanks! i'm going to try to pick one up for a build to compliment my Holset, we should compile a list of known pistons/cranks/rods to use for a hybrid build
 
To my understanding... ALL 7 bolt 4g64 cranks are the same from 93-99, and they share the same rods with the 4g63 7 bolt series.

According to SBR, the 4g64 pistons are compatible from 93-99. They are the same as 4g63 pistons, just 86.5mm vs the 85mm that the 4g63 uses standard.

My problem was that Hollander Interchange said that the 99-2003 4g64 blocks from the Galant were the same, so I thought pistons for a "2000 4g64" would work... apparently not! :(
 
Update:

Well I have the pistons up for sale with a set of rods, and a 4g64 polished crank I have. I've had a couple email me about the setup, only one of them building an engine in a 2000+ Galant.

I'm going to order a set of Wisecos, water pump, oil pump, gasket set on "Black Friday" to help take advantage of some savings. Hopefully I'll turn a little profit with the rotating assembly I'm parting out.

I'll post more when I have more to post I guess.
 
Update:

Well I have the pistons up for sale with a set of rods, and a 4g64 polished crank I have. I've had a couple email me about the setup, only one of them building an engine in a 2000+ Galant.

I'm going to order a set of Wisecos, water pump, oil pump, gasket set on "Black Friday" to help take advantage of some savings. Hopefully I'll turn a little profit with the rotating assembly I'm parting out.

I'll post more when I have more to post I guess.

keep us updated, I'm going to the junkyard to pick my 4G64 up tomorrow, i was going to go with the G4CS out of the 1989-1992 Hyundai Sonata BC it's a 6-bolt, but after calling every junkyard in the surrounding 200 miles to no avail, im just going to settle for the 4G64 7-bolt setup and just build that, i don't see any proof of 7-bolt 4g64's walking more than 6- bolt 4G64's. maybe i can pick one up cheap.

so from what i understand everything from a 4g63 bolts up to the 4g64, i just need intake and exhaust cam gears from a 1994 DOHC 2.4 GS Galant and a timing belt kit for a DOHC 4g64, and a OEM headgasket for a DOHC 4g64.

some questions...

1) what pistons work, i realize that they need to be 86.5mm but what compression should be used

2) what Rods, i realize that Rod size ratio is 1.7 on a 4G63 and 1.5 on a 4G64, so which ones should be used?

I'm hoping for a final compression ratio between 8.0:1 and 8.8:1
 
You can use 4g63 cam gears, just need to degree them properly. More info can be found here: 2G Turbo Head Swap on a 4G64

Also, I'm still trying to figure it out but I was told by (I believe Joe) at SBR that the Cometic 4g64 gasket will work with the DOHC 4g63 head. The rods on a 4g64 are the same as the 4g63, so you can use the eagle h-beams form the 4g63. I'd recommend buying a 98-99 4g64 block because it uses the split thrust bearing. I paid $175 delivered for my block from Ohio.

I am buying the Wiseco pistons listed here Slowboy Racing, Inc. :: DSM :: Engine :: Pistons :: Wiseco Pistons :: 4G64 (w/ 4G63 Head) :: Wiseco 7 Bolt 4G64 Block w/ 4G63 Head for my engine. They are 9.1:1 but with the cometic or mls head gasket and stock surface height I understand final compression ratio would be 8.8:1 - 8.9:1, but someone please chime in on this.

I also just sold my CP pistons tonight so I'm pretty happy with the turn around here. ;)
 
You can use 4g63 cam gears, just need to degree them properly. More info can be found here: 2G Turbo Head Swap on a 4G64

Also, I'm still trying to figure it out but I was told by (I believe Joe) at SBR that the Cometic 4g64 gasket will work with the DOHC 4g63 head. The rods on a 4g64 are the same as the 4g63, so you can use the eagle h-beams form the 4g63. I'd recommend buying a 98-99 4g64 block because it uses the split thrust bearing. I paid $175 delivered for my block from Ohio.

I am buying the Wiseco pistons listed here Slowboy Racing, Inc. :: DSM :: Engine :: Pistons :: Wiseco Pistons :: 4G64 (w/ 4G63 Head) :: Wiseco 7 Bolt 4G64 Block w/ 4G63 Head for my engine. They are 9.1:1 but with the cometic or mls head gasket and stock surface height I understand final compression ratio would be 8.8:1 - 8.9:1, but someone please chime in on this.

I also just sold my CP pistons tonight so I'm pretty happy with the turn around here. ;)

this is the headgasket im going with scroll down and you will have the option for 4g64Cometic Multi-Layer Steel Head Gasket (DSM) - Modern Automotive Performance
 
oh and do you have a picture of what the timing marks should look like at 1/2 tooth advance?

another question, under the link you posted it shows to use 4g64 spark plugs, arent they the same as the 4g63?
 
Ok im going to the junk yard this weekend and want to know for sure what year to get my 4g64 block out of that I can use a 2g head on in my 1g with the least amount of B.S for me to do please!
 
1, I'm not sure how difficult it would be to use a 98-99 block in your 1G. I don't know anything about the 1G cars.

2, I am planning to use that same gasket need2boostpsi

3, No I don' have a picture of the degreeing for use with the 4g63 cams. I was told by a guy on another forum that you can use two OEM 4g64 cam gears from any 2g 4g64, or adjustable 4g64 cam gears from Ebay with no problem, but I've never looked it up as I'm going to stick with 4g63 adjustable gears.

4, According to Parts Lookup at AutoZone, and O'Reilly Auto Parts... NGK 7084 works for both engines but that's probably just a standard OE Replacement guess. I'll look more into that when I get home from work, around 6:00am CST.


Edit: This might explain more for you about the degreeing: http://www.dsmtuners.com/forums/stroker-tech/238269-how-install-t-belt-4g64-ajustable-cam-gears.html
 
so i picked up my 4G64 yesterday from a junkyard in Springfield, MO about 90 miles away. it had been sitting in the weather for about a month so i thought rust was going to be a problem. tore the motor down all the way last night, found the cause of death, BS belt broke and got tangled into the Timing belt causing the the motor to bend valves . things look great on the inside, hardly any bearing wear at all, the motor has a knock sensor which i thought NA's didnt have, also this is a 1994 DOHC 4G64. I'll post some pics up if you guys want.
 
I just ordered my Wisecos from Oliver at Slowboy. It went very well, and he is a pretty awesome guy, with no mis-communication, or trouble at all.

I was trying to get it done on Saturday but it was just a bad day. I ordered a set of 87mm, which is .020 over for the 4g64.

I have my Holset H2E ready to be shipped off to be looked at, cleaned up, and rebuilt if need be... just need someone to send it to who has worked with them before! LOL.
 
I just ordered my Wisecos from Oliver at Slowboy. It went very well, and he is a pretty awesome guy, with no mis-communication, or trouble at all.

I was trying to get it done on Saturday but it was just a bad day. I ordered a set of 87mm, which is .020 over for the 4g64.

I have my Holset H2E ready to be shipped off to be looked at, cleaned up, and rebuilt if need be... just need someone to send it to who has worked with them before! LOL.

so what will your overall compression ratio be? I plan on calling slowboy and talking to them about the pistons and rods for a 4g64/4g63 combo
 
My estimated compression ratio will be about 8.8:1 - 9.0:1, hopefully.
 
Interex, which pistons did you get???
Are they compayible with 162mm rods, on 94 mm crank??
What is your set up in general: crank/stroke, rods, pistons??? LMK. Thanks,Andy.


Andy,

The original pistons I bought were CP... 2000+ 4g64 Pistons. They were 8.5:1, 100mm stroke, 87mm bore.

I sold them the other day and bought a set of 2G Wiseco 87mm, 9.1:1 for my 4g64 with 100mm stroke.

And no, I'm sure they're not compatible with 162mm rods, that's a whole lot of rod there for OEM pin distance.
 
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