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EA81T to MPFI EA81 :)
#1
Posted 10 March 2005 - 01:30 AM
I have a spare carbbed EA81 to use, for the block and pistons... Im thinking I'll need to have the heads shaved alittle to help the compression.
The only thing im unsure of is the ECU and everything. Does the EA81T run with a MAF like the EA82T's? Will the ECU miss the turbo and cause other problems?
-Brian
#2
Posted 10 March 2005 - 01:46 AM
#3
Posted 10 March 2005 - 02:56 AM
#4
Posted 10 March 2005 - 10:02 PM
Also, is there any shadetree way of calculating the CR on an engine, maybe with a compression tester?
-Brian
#5
Posted 10 March 2005 - 11:08 PM
#6
Posted 11 March 2005 - 12:06 AM
#7
Posted 11 March 2005 - 12:22 AM
-Brian
#8
Posted 11 March 2005 - 12:27 AM
#9
Posted 11 March 2005 - 12:29 AM
I was still thinking of having the heads shaved alittle to help. And maybe get a cam for it as well.
-Brian
#10
Posted 11 March 2005 - 12:33 AM
you should be able to run a much higher compresison ratio than the carb'd ones, since it'll have the knock control unit and so on. Sounds nice!
I was thinking of putting N/A pistons in my ea81t to give it some extra oomphh, but well see!
#11
Posted 11 March 2005 - 01:51 AM
-Brian
#12
Posted 11 March 2005 - 01:53 AM
#13
Posted 13 March 2005 - 03:20 AM
The engine sounded and felt real solid. Car ran great, so i think i'll get it and work on it before the heads crack. I noticed there's alot of stuff in the engine compartment, not sure what most of it does but hope i can streamline it alittle

-Brian
#14
Posted 13 March 2005 - 02:36 PM

If you decide to run it Non Turbo with a Carbed Block.....
Compression is all in the Pistons as Someone stated above.....
If you decide to shave the heads , Don't Go more than 20 thousands.....That will bring your Compression up to a Nice respectable 9.2-9.6 to one I can't remember specifics.....
And the MPFI heads will still go on the Block well.....And all Turbo wiring will run it without the turbo Just fine.....
One thing to remember The Turbo motor should be a Hydralic Lifter Motor.....The Carb'ed Block you use Needs to be hydralic as well......
Another thing to check If you keep the turbo unit for now....Verify if the Turbo unit is Oil Cooled only or if it's been upgraded to the Oil and Water Cooled version.....If it is not Water Cooled Stick an Ea-82 Turbo on it.....
E-mail me if needed......I can walk you through what I did to the One I built.....
Later, John......
#15
Posted 13 March 2005 - 05:23 PM
Im glad to hear the comp is all in the pistons. The Carb block is a '84 so it will be hydro as well, no problems there.
-Brian
#16
Posted 14 March 2005 - 01:36 AM
-Brian
#17
Posted 14 March 2005 - 03:30 AM
#18
Posted 14 March 2005 - 05:34 AM
One other thing... Im going to need to use the EA81T Distributor, right? Just sorting out little details.
-Brian
Yeah, use the ea81t distributor. It has a different ignition module in it for the knock control system.
#19
Posted 14 March 2005 - 07:29 PM
-Brian
#20
Posted 14 March 2005 - 07:42 PM
At least that's what I was told.
I've been following along because I am facing a similar delimma. I just picked up a near cherry '84 turbo wagon with a toasted motor. I can't decide whether to rebuild it or drop in a spare EA81 non turbo block, use the turbo heads and nuke the turbo. I'm curios to see how your situation turns out.
Anyway, sorry for hijicking your thread.
#21
Posted 14 March 2005 - 07:48 PM
#22
Posted 14 March 2005 - 08:00 PM

If I put a non-hydro block with hydro heads... what can I expect to go wrong?
-Brian
#23
Posted 15 March 2005 - 01:08 AM
Jeff, no worries mate
That info is exactly what i was looking for.
If I put a non-hydro block with hydro heads... what can I expect to go wrong?
-Brian
I don't know, but back when I was working at a Subaru shop, they never had a problem when the put N/A heads that were origionaly on a hydro engine on a non-hydro block.
#24
Posted 15 March 2005 - 01:43 AM
#25
Posted 15 March 2005 - 02:05 AM
I cant wait to get started. Im waiting for the owner of the 84 to get it smogged. If it fails, I'll be at ground zero.
Im crossing my fingers.
-Brian
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