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ea81 mod' heads Q's


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i picked up a disassembled ea81 motor yesterday (thanks Ross) and have made myself popular with 'she who must be obeyed' by laying it all out on the lounge room floor for inspection:grin: .

 

how much can be machined off the heads before you get either valve interferance or compromised strength in the head,my aim is the highest CR i can get

 

the inlet manifold fitting isn't an issue as i intend on fabricating one with seperate water gallerys and thermostat housing....cold inlet=more power

i've got inlet with the motor so i'll use it to take templates off for bolt holes and inlet port& coolent gallerys

 

how much bigger are the big valves in the hydrolic lifter heads and could the bigger size valves be put into a solid lifter head....would ea82 valves fit?

 

does anyone have any numbers for their torque cam i.e lift/duration etc

 

also do the solid lifter motors run steel or aluminium pushrods

 

cheers for any help

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My Gregory's service manual indicates a maching limit of 0.5mm. But I would wait for someone to come in with a fsm limit.
that works out to be 20'thou i know the flyboys take 40'thou and i fig'er aviation folks being the safety minded ppl that they are(no noise from up the front generaly means its going to hurt:lol: ) that they would leave a very heathy amount in reserve
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in the short term no, we lost everything on the harddrive after we had to reinstall windows after we got virused (now i can't even upload holiday pics because it keeps coming up with some crap about some system error, i hate tecnology :banghead: )

i think dad has a couple of photos from when i was building and playing with the inlet manifold but they won't be much as i only had it half done when he showed up to have a look.

I'll ask him next time i see him

 

sorry man i know there are a few ppl that want to see what it was like before the legalitys stuck their nose in

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Supercharged dude,

 

I have a dual port solid lifter EA81 running 9.6:1 compression, the very bottom of the J in Japan has been levelled off each head.

If that makes sence to you.

Have a look at a head and you will see what I mean.

Major Decking, loves octane!

Matt

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So, Callum, if you put some SPFI pistons in there and plane the head as much as Matty B has, you should have a pretty useful compression ratio!

Just a question as to whether the heads will stay on, but theres only one way to find that out!

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So, Callum, if you put some SPFI pistons in there and plane the head as much as Matty B has, you should have a pretty useful compression ratio!

Just a question as to whether the heads will stay on, but theres only one way to find that out!

hmmm might have to to add spfi pistons to the shopping list, i hope my parts supplier has them listed....... mind you with them saying they have 4 different ring thickness's available,chances are looking good

 

as for the heads staying on, i found these great things called cable ties.....:lol:

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A forged set from an EA 82 rally car, they are 4mm taller than standard.

 

There must be some room in there. BTW my solid lifters run alloy push rods, risky or not do you think?.

Where have you mounted your LPG tank?

Are you on straight gas or do you run both tanks?

I would like to find a gas tank to sit where the fuel tank goes...I want to keep my tray, its not mine anyway.... Groover will be pissed off if I put a tank in there.

I think gas will suit my engine better, high octane fuel is not cheap and twin carbies drink it like its water!

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i am just a little worry'd the spfi pistons possibly hitting the head

You should be sweet, theres a good gap between the top of the block and the top of the piston at tdc on std ea81.

Are you planning on using standard or metal head gaskets?

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A forged set from an EA 82 rally car, they are 4mm taller than standard.

 

There must be some room in there. BTW my solid lifters run alloy push rods, risky or not do you think?.

Where have you mounted your LPG tank?

Are you on straight gas or do you run both tanks?

im on straight gas as its cheaper than petrol and i don't have the hassel of trying to tune for both (hmmmmm its actualy on jackstands at the moment so i guess its currently 'on steel':lol: )

 

have you had any problems with the alloy push rods?

 

4mm taller than standard is a little more than i would have thought possible,....guess you learn sum'it every day

it that a standard ea81 or ea82 piston your comparing to?

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Compared to an EA82 piston (I think...I got a box of parts from a few donor cars here).

 

No dramas with the alloy push rods, I just wondered if they were a weak point.

I suppose I would rather bend one of them than snap something big.

Sort of like a fuse in the circuit..

Would you recommend a swap to gas?

Mileage improved at all?

Come on ... where is your tank??

 

These are a great little motor, I give my car a good hard thrashing just about every time I drive her.

(don't fret, she was built for it, run in for it and she loves it)

5000km sythetic oil changes and a good warm up first is all she asks.

650 - 700km a week, every week.

I am a fan.

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If you can think of any traps or tips, please let me know.

Good luck with the new donk,

Matt

make sure your ignition system is in top shape as you need a really good spark

see if you can get hold of a lambda fuel gas controller its basictly a butterfly valve controlled by a lambda probe that go's between your regulator and your carb, it automaticly tunes the air/fuel ratio they make tuneing a real easy

 

try to get the reg and the carbs as close as possible so the gas doesn't have go any further than necessary between the reg and carb/s

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This whole LPG thing is starting to sound very attractive (cheap, huge CR). Callum, where did you find all the gear? second hand or new?

all second hand, the regulator in brumby came out of a nissan van so i was told, the mixer i was useing with the blower was from a 3.9 foul-coon:lol: as was the tank

 

check round wreckers for gear that looks good or even better is still under cert

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