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N/A EA82 Dual Port Heads?


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the 85 xt and 871/2 xt have mpfi non turbo. the 87 is spider.

 

but they are the same as turbo head minus the oil passage for the turbo, and the drainback tube

 

but their dual portness matches the same as mpfi turbo, and an mpfi turbo car will run a non tirbo with the same intake and no turbo, use a mpfi na boot to connect the throttle to the maf like an spfi

 

the mpfi block is like a tubo but has spfi pistons. it has the turbos case breather on the back

 

the cams formpfi would probably bwe different, so an spfi block, mpfi non turbo heads and spfi cams tirh turbo intake would be a feasable build

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N/A dual port MPFI heads are also on 85 GL-10 engines (no turbo or 4WD GL-10 that year).

All '85 engines except turbos have a 9.0:1 CR (carb and MPFI N/A are same pistons) - less than the SPFI 9.5:1 CR - difft pistons for that year... - but all later MPFI N/A (at least 87-later) use the 9.5:1 CR

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N/A dual port MPFI heads are also on 85 GL-10 engines (no turbo or 4WD GL-10 that year).

All '85 engines except turbos have a 9.0:1 CR (carb and MPFI N/A are same pistons) - less than the SPFI 9.5:1 CR - difft pistons for that year... - but all later MPFI N/A (at least 87-later) use the 9.5:1 CR

My reading of this is that you imply that there were no 4WD GL-10 Turbos in '85. If I misinterpreted that, my apologies; otherwise, I own an '85 4WD gl-10 turbo.

 

And, more to the point of the thread, the MPFI/turbo heads still have a siamesed exhaust port, so it is not a true dual-port in the same was as the Ram's heads.

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Ok that confirms the intake.. now what about true dual exhaust ports like on the EA81 airplane heads? I'd like to run the MPFI spider intake, carb block, mpfi dp heads (with true dual exhaust ports), Carbbed cams?

 

I'm sayin carb'd cams to go with the higher compression carb block? or would the mpfi heads make the compression lower?

 

I'm probably confusing the hell out of you guys.... It'd be easier if I could just line all the parts up and say will this work?

 

*its my for my covert ops ice racing car for next fall*

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It is the pistons that determine the compression for these engines - the combustion chambers in the heads are basically identical

 

EA81 and EA82 are pistons are interchangeable, and I believe EA71 are too -

SPFI/Late (87-later) MPFI N/A - 9.5:1 CR

EA82 carb/early MPFI N/A - 9:1 CR

EA81 carb - 8.7:1 CR

EA71 - ?

 

For the highest CR, you want SPFI pistons (block) - carb cams will lower your torque and hp - that is the combo I would personally use

 

And, more to the point of the thread, the MPFI/turbo heads still have a siamesed exhaust port, so it is not a true dual-port in the same was as the Ram's heads.

 

don't know of any MPFI heads with a true dual exhaust port

 

My reading of this is that you imply that there were no 4WD GL-10 Turbos in '85. If I misinterpreted that, my apologies; otherwise, I own an '85 4WD gl-10 turbo.

 

the 1985 Turbo had almost all the features of a GL-10 automatically, but it did not have the name (from the factory - though swapping decals is easy) - I found this out after looking through my original 1985 buyer's guide, owner's manual, and FSM - my parents ran into that problem when they bought my car new in 1985 - they wanted a N/A FI engine and 4WD; a combination that was not available - GL-10 was N/A FI, but only 2WD, Turbo was FI (of course) and 4WD, but it was only in an automatic transmission (which they did not want) and it had a turbo, which they also did not want

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