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Ea81 build


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Hey guys I am building a ea81 and was told to use ea82 SPFI pistons while other people are telling me to use ea71 pistons and I was told to get a torque grind cam and a get a ea82 intake i wanted to know

Where and which pistons to use

If the intake will work with my block and hitachi carb

If the cam is a good idea

And will I need any machine work for the heads/block to use all this stuff

thank you guys

Sorry If I seem clueless I’m only 18 and have a brat for a project

Edited by YaBoyKingsley
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I'd do what General Disorder had told you 10 times, swap the ej22! The EA81 block has to be split, bore and honed and if done proper, line honed in order to upgrade pistons and cam. Plan on $650 in LABOR only. Add cost of pistons and rings $200, add cam grind $100-200, ea82 manifold $40, add gakset set $100, add oil pump $100, add Weber swap $300. Is $1500 worth 90hp and no torque? $1500 I can buy an EJ22, Weber conversion, intake manifold and disty from SJR and have a carbed ej22 with 130hp and 130 ftlb. I wish I would have go this route and I'm only $600 in on my cars engine lol. Cool project, good luck and have fun learning!

Edited by wagons
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EA82 SPFI pistons will give a slightly higher compression than EA71. Both will give higher than  EA81 pistons. EA82 are also far easier to find and weigh less.

Contact Delta Cams for a suitable grind. They can be difficult to contact electronically, phone call is best. Ken is the best guy there to deal with (he did my EJ20 SOHC cams).

EA82 intake is bolt on. Use a EA82 y-pipe also, slightly larger than your EA81.

No machine work required if you just want to swap pistons, though I'd recommend at least getting the bores checked (take the block to a decent machine shop and ask their opinion). Don't buy your pistons until you get to this point, in case you do need to go up a size from stock.

Value of adding a Weber is debatable. I'd rather spend the money on a SPFI kit which sends the right amount of fuel into the engine rather than simply more like the Weber does...

Edited by dfoyl
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I fully understand.No EJ swap yet.

 

People have been screaming convert to EJ for a long time for good reason.

 

You and I also have good reason.

 

You also want to learn from scratch

 

Good on ya

 

Is money a problem? Or are you trying to do this on tight budget?

 

Are you driving this yet?

 

You say you are building or planning to build?

 

I had trouble finding spfi pistons new so bought pistons for the 1600 cc EA71. New and oversize bought first so machine shop can have them to measure and rebore to suit

 

Most rebores require head studs removed from block

 

They ate a bugger to get out

 

Are not ate!

 

M11 threads 1.5 mm pitch I think

 

I have never put pre loved pistons in a rebuild but looks like dudes do. Need careful measurement for sure

 

Mist cranks not need regrind and undersize bearings, just a linish and standard size bearing shells. They are cheap.

 

Think I got ea71 pistons from US about $40 set in oversized. So cheap I bought several sets in different sizes.

 

Can you buy top grade fuel? To run new beast on

 

The Y pipe others mentioned is the exhaust from heads to first flange join. I fitted one from EA82 to my EA81 is just half inch longer? And pushes exhaust back a little.

 

Resulted in 120 kmh in third instead of 110!

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Always good to get stuff machined and serviced such as heads resurfaced to reduce head gasket fail

 

How much do you want to rely on this? Farm hack, just around town, to from school work or highway travel?

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Manual or auto trans?

 

Can grind I prefer for solid lifter is 16/56 with 0.235" lift

 

Went wilder with 20/60 and lost torque when loaded

 

When heads shaved intake manifold bolts holes get closer so the bolt holes of manifold each end need larger dia drill through them

 

Find someone who goes ej they usually hate each stuff and may give you old bits for nix. Ea82 carb on its manifold will fit

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What dfoyl says is good BUT when have bought pistons here in Oz for my ea81 builds the box was labelled ea71,ea81,ea82 so a compromise piston to suit all three engines

 

This time specifically bought old stock ea71 pistons...yet to build and gonna be an ea82

 

I run ea82 using mpfi or turbo heads that are two intake ports on heads manifold to suit and feed it propane to save dicking around with carnies n crap in my Brumby

 

My first total rebuild ea81 in 2001 cost $1000 for me to build lasted 180,000km hard revving

 

Second ea81 build 2008 same money. Got 120,000km now got blow by and buttermilk

 

Money well spent each time

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