1g block with 2g head

[sleeperawd92]

I have a head that I pulled off of a galant that I have built, only t find out it is a 2g head. I know its pretty dumb that it took me this long to find out. I know this will seem dumb, but has anyone ever mated a 2g head with a 1g block?? I know the head studs are different sizes. Is it possible to make the holes larger to fit the 1g studs??

 

[bryanwheat]

If you use the stock head bolts than it will go on just fine without enlarging the holes. If you use studs than you will likely have to enlarge them. Some people say that it is necessary to increase the size of the bolt hole that supply's the head with oil a bit, but after a little testing i've found that you will get plenty of oil without doing so. You are also going to have the issue with the intake manifold. The 1g manifold will work just fine on the 2g head, but you are going from a large port to a smaller port with no contour.

 

[sleeperawd92]

I ported out the intake in the head quite a bit and tried to make it so that the transition from the 1g manifold to the 2g head would be as smooth as I can make it. Do you know what size drill I would need, or any other special tools?

 

[blazindominic@n]

I currently have a 2g head on a 1g block. All that was needed was to widen the head stud holes. DO NOT PORT THE 2G head you defeat the purpose of having the 2g head. Most people use the 2g head because of how efficiently it flows in comparison to a 1g head. If you port the 2g head you might change the way if flows.

Smaller ports were used to increase velocity in the air that flows. Every evo after the evo3 has had smaller intake ports for that reason.

 

[91stocker]

I ported out the intake in the head quite a bit and tried to make it so that the transition from the 1g manifold to the 2g head would be as smooth as I can make it. Do you know what size drill I would need, or any other special tools?

Im pretty sure you just destroyed that head.


The 1g intake mani is garbage anyway, why would you want to match that pos?

 

[sleeperawd92]

Ok thanks. I wasn't sure if it had been done before. I only ported the outside area of the intake on the head so that it makes a smooth transition but still flows to a smaller diameter. I was hoping this would give the air flow a venturi effect causing the air that flows into the larger manifold to speed up as it transitioned into the head.

 

[91stocker]

Why not use a 2g mani? Not tryin to be an ass, but the port size, shape, and design make it what it is. You go hogging out the ports it will surely worsen flow.

 

[sleeperawd92]

because i have a 1g manifold and i figured if i made the head mate with that manifold it would still work. since i have the larger 1g runner meeting with the more narrow 2g intake port you would think that you could still get an increased air flow since the air is moving from the larger are into a smaller one.

 

[brian9397gsx]

Wow , you should of searched before porting that. I run a 2g head on both my 1gs, my 93 is a 6bolt with a 99 head and evo/rvr intake manifold. My 91 is a 95 head with a Hyundai intake which looks like a 1g but has the smaller ports.

In both cases I used a 1/2 drill bit and enlarged the holes and performed the oil port mod 1 and 2 to the heads.

 

[sleeperawd92]

what is the oil port mod?

 

[brian9397gsx]

I wont tell you to search but I also wont spoon feed you either, look in the tech archives and do some reading.

The member who posted them is bogussvo, a very knowledgeable member of this site who happens to be a machinist by trade.

 

[sleeperawd92]

ok thanks.

 

[Turbotsiawd]

sorry we have to play hard ball just
trying to give you the tools you will need
on your next problom

 

[blazindominic@n]

A 1g manifold wont seal correctly on a 2g head. I tried to put my 1g manifold on my 2g head when i did the swap and it wouldn't seal so i decided to just use the stock 2g manifold. I thought the same way you did...big port manifold and port match job on the head then i did some research and i realized the risks that would be involved on a naturally aspirated motor this might be a nice modification but with a turbo motor flow is a crucial and its design shouldn't be altered to much or it wouldn't work the way it should.

 

[sleeperawd92]

its all cool guys.. im just trying to make everything work. by the way i did find the tech article on the oil port mod. hopefully ill have the head on the car by monday.

 

[bryanwheat]

A 1g manifold wont seal correctly on a 2g head. I tried to put my 1g manifold on my 2g head when i did the swap and it wouldn't seal so i decided to just use the stock 2g manifold. I thought the same way you did...big port manifold and port match job on the head then i did some research and i realized the risks that would be involved on a naturally aspirated motor this might be a nice modification but with a turbo motor flow is a crucial and its design shouldn't be altered to much or it wouldn't work the way it should.

A 1g manifold will seal to a 2g head perfectly fine if you use the 1g gasket. a 2g intake on a 1g head is a little different matter though.

 

[sleeperawd92]

i have the 1g magnus heat barrier intake gasket for the head. i guess the only thing left would be to see how the 1g intake on a 2g head combo works out. im not trying to say that it will work, but i might as well run it and see if it works since its already done.

 

[bryanwheat]

I've ran a 1g manifold on a 2g head years back. I was only running a 14b at around 16 psi, but i really didn't notice any lack of power or anything from the step in the port.

 

[sleeperawd92]

that gives me some confidence. thanks. almost every other post on here has be saying that i shouldnt run a 1g intake on 2g head. its just an idea i had, whether it actually works or not is completely different.. i hope to break 300 on the dyno, if not then that could be one of my problems. well just have to wait and see.

 

[bryanwheat]

It is not ideal, but it will work.

 

[sleeperawd92]

looks like i will have the holes drilled out on monday. my friends dad has a vertical mill, he says he can drill them out for me.

 

[JusMX141]

I know this will seem dumb, but has anyone ever mated a 2g head with a 1g block??

Nope, you're the first.


Wait a minute....no you're not.

http://www.dsmtuners.com/forums/newbie-forum/420725-dreaded-crank-2g-head-1g-block.html

http://www.dsmtuners.com/forums/newbie-forum/416893-can-7-bolt-head-go-6-bolt-block.html

http://www.dsmtuners.com/forums/cylinder-head-short-block/224571-2g-head-1g-block.html

http://www.dsmtuners.com/forums/newbie-forum/409816-accidently-bought-2g-head-have-1g-block.html

http://www.dsmtuners.com/forums/cylinder-head-short-block/382223-2g-head-6-bolt-block-98-gsx.html

http://www.dsmtuners.com/forums/newbie-forum/356695-6bolt-block-96-2g-head.html

http://www.dsmtuners.com/forums/newbie-forum/355144-6-bolt-block-7-bolt-head.html

http://www.dsmtuners.com/forums/newbie-forum/321400-head-studs-6-bolt-block-2g-head.html

http://www.dsmtuners.com/forums/newbie-forum/317367-studs-6bolt-block-2g-head.html

http://www.dsmtuners.com/forums/new...t-head-6-bolt-block-plus-other-questions.html

http://www.dsmtuners.com/forums/newbie-forum/253937-2g-head-1g-block.html

 

[turbofc4g63]

looks like i will have the holes drilled out on monday. my friends dad has a vertical mill, he says he can drill them out for me.

hey woh thats me and my father

 

[dsmlover07]

Thats a lot of threads on one topic.

 

[2slow4utsi]

I have a head that I pulled off of a galant that I have built, only t find out it is a 2g head. I know its pretty dumb that it took me this long to find out. I know this will seem dumb, but has anyone ever mated a 2g head with a 1g block?? I know the head studs are different sizes. Is it possible to make the holes larger to fit the 1g studs??

Is this a serious question?