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4g63 head on a 4g64

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Was that about 300 for both of them??

Yea but you need a laptop to run evoscan to. You can get away with an safc I to ( i am) but it annoys me because the rpm adjustment points are to far spaced and only allows for 8.

Anyways only get a neo if you can find one used for like $200 then it would be worth it because you can do 16 rpm points.

dsmlink is the way to go if you are going with the dohc swap though...
 
Yea but you need a laptop to run evoscan to. You can get away with an safc I to ( i am) but it annoys me because the rpm adjustment points are to far spaced and only allows for 8.

Anyways only get a neo if you can find one used for like $200 then it would be worth it because you can do 16 rpm points.

dsmlink is the way to go if you are going with the dohc swap though...


Well, I'm not looking to spend a LOT but not looking to go the cheapest route either.
Got a link for evoscan / safc I?
 
For clarification, you CAN'T use the stock 4G64 pistons with any 4G63 DOHC head as they are machined with different valve reliefs for the SOHC and your DOHC valves will hit pistons!!

Pictured here are the OEM SOHC 4G64 pistons & a set of DOHC Arias pistons.

This only applies to 8 valve 4g64 engines, my 4g64 valve have 2 reliefs on one side and it is from a sohc 4g64 16v.

So, you cannot say that you can't use stock pistons there were Dohc 4g64's.
 
I am setting up my g4cs sohc block with 4g63 head so we will see if the stock turbo cams cause the valves to hit the pistons without the correct 4 reliefs. The pistons I have are identical to those pictured earlier in this thread with sohc valve reliefs and basically flat tops. I already rotated by hand and they do not make contact, but running will determine for sure.
 
My 4g64 16v sohc pistons out of a 94 galant gs I believe.

To save all the trouble I'll be having the pistons cleaned up and you can buy them from me with the rods if you want PM me.

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This only applies to 8 valve 4g64 engines, my 4g64 valve have 2 reliefs on one side and it is from a sohc 4g64 16v.

So, you cannot say that you can't use stock pistons there were Dohc 4g64's.


Well anything is possible, I guess... But from the sounds of it, why would you run stock N/A pistons & rods with boost? :confused: What's the compression ratio of those NA 16v SOHC pistons anyways?

Your pics illustrate exactly what I was referring to originally: The OEM 4g64 (8 or 16 valve) SOHC pistons do not have the 4 valve reliefs that are required to run a 16 valve 4g63 DOHC head. -The rare 95'ish 2.4L NA DOHC Galants would be the only exception, but you would still be dealing with the high(er) compression ratio.

IMO, the compression ratio would be to high to have any sort of fun with, as previously mentioned.

If you are planning on going with a 4g63 DOHC head, don't forget the freeze plugs for the oil drain galleries.. I'd be sure double check it by seeing what drain holes are not covered when you slap a 4g63 head gasket over it (that is unless you plan on throwing the 16v SOHC head back on).
 
Well anything is possible, I guess... But from the sounds of it, why would you run stock N/A pistons & rods with boost? :confused: What's the compression ratio of those NA 16v SOHC pistons anyways?

Your pics illustrate exactly what I was referring to originally: The OEM 4g64 (8 or 16 valve) SOHC pistons do not have the 4 valve reliefs that are required to run a 16 valve 4g63 DOHC head. -The rare 95'ish 2.4L NA DOHC Galants would be the only exception, but you would still be dealing with the high(er) compression ratio.

IMO, the compression ratio would be to high to have any sort of fun with, as previously mentioned.

If you are planning on going with a 4g63 DOHC head, don't forget the freeze plugs for the oil drain galleries.. I'd be sure double check it by seeing what drain holes are not covered when you slap a 4g63 head gasket over it (that is unless you plan on throwing the 16v SOHC head back on).


Looks like you need to learn about this a bit more, the head CC will be different for this engine it was out of a 94 galant GS 9.6:1 compression, and the piston is more like a 4g63 piston then an 8 valve. I don't have the head but a 4 valve head would have the volume closer to a 4g63 head as opposed than an 8 valve 2 valves per cylinder head.

Any of the 4gXX series oem pistons will be done if they are detonated on anyway.

It's 2009 you should know by now compression is nothing but more efficient unless you have no tuning to begin with to make use of it the engine sucks with low compression.

So this issue is being fixed with 1400HD 4g64 pistons which are 9.7:1 .

I know what I'm doing as far as oil drains go but thanks for the advice.
 
The 4g63 turbo pistons can tolerate GOBS more detonation than the higher compression stock n/a pistons you have (and I have since I have that same block on my porch). They have the same ringland spacing as the n/a 4g63 pistons.

But I agree that if you want to build a motor for a decent HP goal (like 450 or more) AND run more efficient high compression, then you really need aftermarket forged pistons. I doubt of the OP is looking for this power though.
 
Looks like you need to learn about this a bit more, the head CC will be different for this engine it was out of a 94 galant GS 9.6:1 compression, and the piston is more like a 4g63 piston then an 8 valve. I don't have the head but a 4 valve head would have the volume closer to a 4g63 head as opposed than an 8 valve 2 valves per cylinder head.

OK, so the heads have the "same" CC rating thus not changing the final compression ratio too much... What about the static compression ratio of the pistons themselves? Surely not as significant as any differences in the head types but one would think that a flat faced piston with fewer valve reliefs would take from the total combustion chamber volume, right? -Now compare that to a dished face piston with two more valve reliefs cut into it. -More volume in the combustion chamber.


Any of the 4gXX series oem pistons will be done if they are detonated on anyway.

Absolutely. -That goes back to proper engine management though.


It's 2009 you should know by now compression is nothing but more efficient unless you have no tuning to begin with to make use of it the engine sucks with low compression.

Yep. However, you are narrowing the margin of error for tuning while running a higher compression. The majority of the users on this forum probably need this extra buffer, at least for a first build, and especially when adding boost to an NA car.


So this issue is being fixed with 1400HD 4g64 pistons which are 9.7:1 .

I don't care what pistons are used, with higher compression and the decreased margin of error, ANY piston will fail for even the slightest change in tune... The higher the compression ratio, the more sensitive the motor will be to these changes, not to mention higher octane fuel requirements... I doubt the OP was going to make this a trailer queen that only drinks the good stuff.


I know what I'm doing as far as oil drains go but thanks for the advice.

I'm so glad. I will sleep easier knowing that I don't have any extra freeze plugs installed in my 4g64 hybrid. If anything, this was included for the good of the thread.

...and here I thought you were some wanna-be vendor trying to pawn-off some old scrap pistons & rods you had taking up space in the shop on some unsuspecting first time builder (no offense Project 1g). Wow... tough times man?
 
Holy glad-you-posted-on-the internet-so-that-I-can-interupt-you-repeatedly-by-cutting-up-your-quote ;):D

I don't care what pistons are used, with higher compression and the decreased margin of error, ANY piston will fail for even the slightest change in tune... The higher the compression ratio, the more sensitive the motor will be to these changes, not to mention higher octane fuel requirements... I doubt the OP was going to make this a trailer queen that only drinks the good stuff.
Alcohol IS the good stuff. . . In so many ways.
 
Yep. However, you are narrowing the margin of error for tuning while running a higher compression. The majority of the users on this forum probably need this extra buffer, at least for a first build, and especially when adding boost to an NA car.

You need to re-evaluate the basic fundamentals a higher compression isn't an increase margin of error. You need less with more and more with less, ignition timing.

As for your comment on the newer pistons they are a dish still not flat top, simply put if you can't compensate for the new pistons don't use them?

I don't care what pistons are used, with higher compression and the decreased margin of error, ANY piston will fail for even the slightest change in tune... The higher the compression ratio, the more sensitive the motor will be to these changes, not to mention higher octane fuel requirements... I doubt the OP was going to make this a trailer queen that only drinks the good stuff.

Actually no, I can detonate on a forged piston far more than any cast piston, and I'm not talking about the OP I'm talking about myself. Regardless low compression isn't needed unless you like running pump fuels on higher boost levels with more ignition timing.



I'm so glad. I will sleep easier knowing that I don't have any extra freeze plugs installed in my 4g64 hybrid. If anything, this was included for the good of the thread.

And there are about 6 more other threads with the same info, what's your point?

...and here I thought you were some wanna-be vendor trying to pawn-off some old scrap pistons & rods you had taking up space in the shop on some unsuspecting first time builder (no offense Project 1g). Wow... tough times man?

Getting a bit personal?
 
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