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6 vs. 6 and a half


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the difference, as near as i can tell, is in the technology. for example...my 86 has a denso (or something to that affect) distributor with a 6000rpm redline, while my 87 has a hitachi distributor with 6500rpm redline...one can assume that there is different ignition curves and as such rev limititions due to limited advance. and i'm sure someone will mention that the cams are different too, providing different power bands.

 

the late 80's and early 90's provided a lot of different changes...i would say that these are just the first steps to the better things that came after.

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Red line doesn't mean much.. It's just a "safty" warning. I took my EA81dc to 8K, and it's still happy.... well it needs a rebuild, but still for a 250,000km motor..

 

Maybe you get less predestination with better fuel control?

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I went from an 86 carbed Ea82 engine to a 90 and used the same disty. My redline now is close to 6800rpm from the 6000 of the 86 engine. I think its more to do with the cams and the compression then the disty.

 

I think you're referring to where the valves float, which is mostly dependent on the condition of the valve springs, my better-running '88 could easily hit 7200 before the valves would float. the red-line is what's marked on the tach, the ECU on the newer cars will actually cut fuel to prevent you from exceeding the redline, as the valvetrain is much stronger and would probably rev well beyond the marked limit.

 

 

I think it's carbed vs FI. my buddy's '86 and my old '85 carbed EA82s both have 6k rpm redlines (although I didn't realize it on mine until long after I junked the car and found the old gauge cluster, I swapped the cluster for one from an '88 with a 6.5k redline within a few weeks of buying the car)

 

both my '88s, and my '92 are marked at 6500.

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I think you're referring to where the valves float, which is mostly dependent on the condition of the valve springs, my better-running '88 could easily hit 7200 before the valves would float. the red-line is what's marked on the tach, the ECU on the newer cars will actually cut fuel to prevent you from exceeding the redline, as the valvetrain is much stronger and would probably rev well beyond the marked limit.

 

 

I think it's carbed vs FI. my buddy's '86 and my old '85 carbed EA82s both have 6k rpm redlines (although I didn't realize it on mine until long after I junked the car and found the old gauge cluster, I swapped the cluster for one from an '88 with a 6.5k redline within a few weeks of buying the car)

 

both my '88s, and my '92 are marked at 6500.

Your right i ment when the valves float. when i had the carbed 86 block they would float at 6000, now with the carb on the spfi block i havent taken it up past 6800 because i dont want to break something. Im sure it would go to 7200 :)
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Your right i ment when the valves float. when i had the carbed 86 block they would float at 6000, now with the carb on the spfi block i havent taken it up past 6800 because i dont want to break something. Im sure it would go to 7200 :)

 

Last time I redlined my Loyale the crankshaft pulley came off...Shouldn't do it again, although now my Loyale's gonna be totaled. Engine still will work with a new oil filter though!

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In 87 subaru Changed the piston design of all EA82 engines slightly. They offset the position of the wristpin in the piston by 1mm to the thrust side. helps keep the piston stationary in the bore and I believe this is why 87+ have a 6500 rpm redline.

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In 87 subaru Changed the piston design of all EA82 engines slightly. They offset the position of the wristpin in the piston by 1mm to the thrust side. helps keep the piston stationary in the bore and I believe this is why 87+ have a 6500 rpm redline.

 

Loaded question...

 

I guess I could tell simply from the redline on my tach, but are you saying an 87 engine would have this modification?

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Loaded question...

 

I guess I could tell simply from the redline on my tach, but are you saying an 87 engine would have this modification?

 

Yes in 87 they did this to all ea82 pistons. That's why 85,86 pistons are marked only with an *up* marker. 87 plus pistons are marked with *up* and an arrow that points forward so the pistons go on the correct side for the offset.

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