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Rooba Doo

EA82 carb EA82 SPFI head compatibility

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Hey guys this is my first time using USMB and I have learned a great deal of stuff just browsing around. Anyway, just wondering if the heads on EA82 carb engines interchange with the heads on EA82 SMPI engines. Im not exactly sure what the problem is :confused: but my buddy says he is having trouble with one of his heads in his 4WD GL wagon (ea82 smpi) Now I have a 4WD GL wagon (ea82 carb) with an engine that runs. Just wondering if I could help him out with the parts I have.

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Yes, the heads will swap over just fine. Internally, the two engines are IDENTICAL except for the pistons and maybe the cams. (The SPFI motor has 9.5:1 compression compared to the carb's 8.7:1, which is caused by the piston variation.)

 

Your carbed heads have a port in the exhaust manifold where air is inducted to help the cat burn excess fuel better. If you put the carbed heads on the SPFI motor, you have to block off those ports, as extra air in the exhaust will confuse the oxygen sensor.

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Yes, the heads will swap over just fine. Internally, the two engines are IDENTICAL except for the pistons and maybe the cams. (The SPFI motor has 9.5:1 compression compared to the carb's 8.7:1, which is caused by the piston variation.)

 

Your carbed heads have a port in the exhaust manifold where air is inducted to help the cat burn excess fuel better. If you put the carbed heads on the SPFI motor, you have to block off those ports, as extra air in the exhaust will confuse the oxygen sensor.

 

Hey snowman FYI, the EA82 carb is 9.0:1 it's the EA81 that's 8.7:1.

 

Oh there is another reason to plug the ports, if you don't you'll have a lot more noise under the hood, if you care about such things.

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Yes, the heads will swap over just fine. Internally, the two engines are IDENTICAL except for the pistons and maybe the cams. (The SPFI motor has 9.5:1 compression compared to the carb's 8.7:1, which is caused by the piston variation.)

 

Your carbed heads have a port in the exhaust manifold where air is inducted to help the cat burn excess fuel better. If you put the carbed heads on the SPFI motor, you have to block off those ports, as extra air in the exhaust will confuse the oxygen sensor.

------------------------------------------------------------------------------------------------------------------------------Thanks SNOWMAN I think im pretty sure what your talking about. A tube from the air pump going into the EX manifold?? but if not The 'PORT' you talk about on the (EA82) carbed heads........is it in the actual HEAD or on the Exhaust Manifold itself and if so could i get away with changing the manifold (using- spfi block, carbed heads, spfi manifolds- if they bolt up) or would this eliminate the hole for the O2 sensor OR if all else fails could i fill the holes (not O2 sensor hole :) ) with weld Sorry for the confusion

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the holes in reference are on the side of the exhaust port, on carbs it runs up to the back of the head.

 

on spfi this hole is not present, so you will have to block it. one cheap way i did such a thing was to cut the pipe ff and weld a bolt or spark plug in the inch length of pipe i left

 

there is an egr port on the top of the passenger head, its the same between carb ans spfi so everything will fit the same

 

if using the carb heads keep the spfi cam and tower to bolt on top of the head

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