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7 bolt engine with 1g head....

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John Miller

Proven Member
172
67
Jan 27, 2020
Watertown, Wisconsin
Hello my fellow dsm enthusiasts!!

I have ran into a bit of an issue, but not a huge one... First I am new to the dsm world and am currently working on my first 2g elipse gst. I build an engine and put it in the car, however I somehow managed to totally not notice I used a 1g head on a 7bolt short block... I know this swap has been done before, but I'm not sure what I'm gonna need to finish it or if that is even possible. So what all do I need to do to have a running 7 bolt with a 1g head? Please remember I'm a newbie so simple language :)
 
Not sure why anyone would want to do this. The 7-bolt has the weaker bottom end but better cylinder head for low-power setups. Just stick to pure 7-bolt for simplicity.
 
You can do that but it would require some extra parts and works. So the easiest way is you use a 2g 7 bolt head as @Canadian_CD9A mentioned above.
As @delta448 mentioned above, you would use a 1G intake manifold and relocate some accessories such as the coil pack and the PTU, and you can't mount the MDP sensor on 1g intake manifold so you would need to deal with it, too. cancel or use an adapter etc. Also you need to deal with the thermostat housing/water pipe and rerouting the radiator hoses.
 
I feel like a few terms need to clarified here. 7 bolt can refer to both 1g and 2g engines. Doesn't really matter for this discussion but should be noted. 1g head can also be 6 bolt and 7 bolt. You didn't specify but also doesn't really matter in this case. You will notice differences in the intake ports and you will likely want to run a 1g intake manifold. There are no provisions for an under cam gear cam sensor but since you are 97 I assume you have the 97 to 99 style sensor. I cannot recall but I don't think all oil pumps have a provision to bolt on the crank sensor. You will need the crank sensor unless you convert to a 1g cas. As stated above you also have to sort out the differences in 1g and 2g thermostat housings and coolant hose hookup including the water pipe.
 
I feel like a few terms need to clarified here. 7 bolt can refer to both 1g and 2g engines. Doesn't really matter for this discussion but should be noted. 1g head can also be 6 bolt and 7 bolt. You didn't specify but also doesn't really matter in this case. You will notice differences in the intake ports and you will likely want to run a 1g intake manifold. There are no provisions for an under cam gear cam sensor but since you are 97 I assume you have the 97 to 99 style sensor. I cannot recall but I don't think all oil pumps have a provision to bolt on the crank sensor. You will need the crank sensor unless you convert to a 1g cas. As stated above you also have to sort out the differences in 1g and 2g thermostat housings and coolant hose hookup including the water pipe.

I apologize for not specifying the exact head design. The engine block I am using is a 1996 7 bolt 4g63t. The head I am using I believe is a 6 bolt 1g head. The intake ports are larger and the thermostat housing looks a triangle with tree bolts.
 
Yup you have a 1g head. 6 bolt heads would have larger head bolt holes too but that isn't a problem. Did you look at the 1g in a 2g pages?
 
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