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any tips on EA82M build? (EA82T with 9.5:1 compression block)


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Hey everyone,

 

My 87 'Rally Wagon' had recently started showing signs of HG failure (frothy coolant & coolant loss) so I pulled the engine and found that it was just my heads that were toast... so, I've decided to keep my low compression block (7.7:1) for a spare and I'm putting the old heads onto an XT block for fun(: the XT engine-(MPFI 9.5:1 comp)

 

What I want to know about this is if there's anything other than the obvious dangers of running boost with high compression.. if anybody has built one of these and run it dependably for any amount of time, what did you do? What should I look out for? And what's the most common failure point of these?

 

This is my test engine, and if I like it I'm going to build a fresh block, ported heads, ported turbo, and eventually a propane set-up

 

Thanks everyone for any input, I'm not expecting anything more than a mass amout of power and eventually a big bang over time with this one haha(: but id like to delay the bang until I get it all running right

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another says ...anyway , EA82M code has been used before - M is for Mongrel :) ....it is big ends that eventually fail in turboed NA boxer comp ratios. Has not stopped others before, just don't think they ever come back and tell of demise.

I have an EA81 NA solid with comp crank pressures of 180 that I plan to turbo just to see what and how long ...and how HARD it goes, with propane, EA82 spfi inlet for its throttle body, also have been sitting on for years a device to retard timing on boost of non MSD coils. Just need more time, some spendy, an exhaust, few more bits and maybe a tow voucher :)

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If you are going to run a higher compression ratio with turbo you will need to control timing and fuel so you dont destroy youre engine from running too lean. because the factory ecu wont know that anything has changed. if you get a proper air fuel tuning device and make sure the engine is solid it will last quite a while. just dont cut any corners, an old worn out engine will grenade eventually. depends on how much boost you want to run. you can change the compression ratio of the xt engine if you put different pistons in it. With high compression and boost you raise the risk of spark knock. wich is a scary area. you will have to run higher octane fuel and make sure you dont run too lean or its all over. if you can properly tune it it would be more powerful. lower comp ratio allows for running more boost without worrying about spark knock. More boost or higher compression calls for fuel system/ Engine management upgrades if you want to do it right.

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I plan on using a mixture gauge, exhaust temp gauge, boost gauge, and will be usinng very high octane gas(:

 

I know it probably won't last long but if it runs dependable and correct then I'm going to go on a full build with propane 9.5:1 comp ratio and a VF11 turbo.. I just want to know if anyone has done this before and what they did to keep it running good/dependable

 

And I know all about how turbo engines work... I just wanna build a monster for fun while I daily drive my new CCR EA82T in my loyale(:

 

Thanks for the replies!!

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It should run fine, but detonation is what kills higher compression ratio forced induction engines, and the rod bearings going is probably a result of the pounding of detonation. You can control detonation by retarding the timing or running rich, but both of those reduce power. Intercooling to lower intake temps can help to some extent, but what works the best is water injection. Look up cooling mist/snow performance ect. or build your own setup. I ran a 9.6:1 engine on more than 12psi of non-intercooled boost from an overspun roots supercharger, and with enough winter grade windshield washer fluid (30% methanol, 70% water and a bit of blue dye) sprayed in, it ran great and is still running today.

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running rich on propane is not same as running rich on gasoline - richer propane is hotter and some propane gurus say that sometimes retarding timing under boost on propane is not always the best thing to do. Woodswagon - was your 9.6:1 engine a boxer by any chance ? Love to see pics either way :)

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I happen to have a good friend who has taught me quite a bit on propane forced induction(:

 

running lean on propane gives more power.. as does gas.. but with propane as you go leaner you don't run the risk of burning valves, unlike gas. Running too rich on propane burns valves

 

Hence why I plan on building a fresh high comp. EA82T or (EA82M) to run propane at around 10psi boost

 

My friend has a stock EJ22 with heads modified to 11.5:1 compression and fully ported running propane and distributor..

 

Thanks everyone! Jono, you happen to have pics of your propane set-up??

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+1 for WoodsWagon. Here's a break down of what you're going to have to look at to make this work and SURVIVE and you're going to be looking at $3K-$4K to do it. Not worth it IMO, but...

 

You will need the forged pistons and rods from Ram. There's $700 for pistons right there. Running high compression and boost will kill regular pistons in a heartbeat. Ask me how I know. You will need to O-ring the heads and create copper head gaskets. Only one place made them, and they don't anymore. No current HG's are going to hold for any length unless you way over torque them and then you're going to pull the threads out of the block, which brings me to the next item. You'll need to Time-sert the block and install studs for the heads so you can over torque and things won't stretch, rip or break. You're going to need to port the exhaust, install bigger valves and get a higher lift or longer duration or both on the exhaust lobe. If you don't, you're going to create excessive back pressure as EA82's flow like crap. 4" downpipe and minimum 3" exhaust. Intercooler. 'Nuff said. Methanol water injection is in order as previously mentioned or detonation will wipe out your pistons, bearings, HG's and valves. Stand alone fuel management system with knock control and a higher voltage coil or you're going to blow the spark out. Bigger injectors and higher output fuel pump. Boost controller with outputs for the methanol injection. Then there's all the goodies for your propane injection. Hundreds more there. Machine the crank to the tightest specs or your bearings will be short lived. Have the entire rotating assembly balanced. Bigger radiator with an inline surge tank. EA82's have a horrible coolant flow design and overall, the engine was barely adequate in stock form. It's not a bad engine, it just doesn't take extreme modding well at all. You said, dependable over time. Yeah, you could probably cut a few things, find deals on the control portions of the system and do a lot on your own, but I learned a long time ago, it's more expensive taking chances than being certain. Not saying taking chances isn't fun. Seen and learned some great things from that school. lol Comparing an EJ22 to an EA82 is like comparing a WRX to a Pinto. Not even close to the same creature...

Edited by skishop69
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Do you really think that if I had 3-4k$ that I would dump it into an EA82M?!? I built this engine for 50$ and with 3 old EA82s... I just want to see how the stock ECU will handle it..

 

And yes I did compare an EJ22 to an EA82(: my stock (mostly) EA82T has beaten at least 5 EJ22s and an EJ22t on street and on my dirt tracks, and was just over 250k miles and I've seen too many EJ engines fail with less miles than that, so yes they're comparable haha

 

I just wanted to know how the guys that have run these engines modded or changed shtuff to make it run better

 

Once I get to propane ill have less problems, but until then I just wanted to know what the people who've made these before ran into with the stock setup

 

Thanks for the replies! I was just waiting for someone to say "put a fortune into it and watch it explode!" Haha :P

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The stock ECU won't handle it. There's not enough 'give' in the factory fuel and spark maps. You'll go lean, have detonation and the ECU won't be able to correct. Poof! lol Stock EA82T's will barely take 12 pounds of boost without certain death. Bump up the compression to 9.5:1 and then boost that high or more...... No bueno. Just pointing out that if you're combining used engine parts to make a 'good' motor, you bump up compression and boost plus run the stock ECU, you'll be lucky if it will stay running and if it does and you crank it up, it will be a very short lived experiment. Heed my words on the EA/EJ comparison. I have both, have modded both and can assure you from experience, the EA isn't worth heavy modding. Again, I'm not saying don't have fun, just be aware it'll be short lived. At the VERY least you'll need stand alone fuel management.

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Boosted ...may have some pics in PC, will look later. The EA82T engine is currently in storage waiting for transplant time, thoug is simply fresh air Impco 200 mixer and L converter. Is mixer before turbo - so gasses get a nice tumpled effect and preheat before intake manifold :) I tried mixer direct on throttle body for turbo blows through - does not work due to the odd intake pulses of a 4 cylinder with turbo boosting it - works fine non turbo though. I have seen some extensive mods to the same impco components so it did work as turbo blows through , but very complex modding.

 

After reading skishops account, i think I will motorvate self to extract some EA82T pistons to shove in the EA81 and see how they measure up .....he would not be the first to tell of the disatsers that can result from turboing NA boxer  and factory bits

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My friend just put an Impco mixer at a 90* elbow right before the throttle body and it runs awesome with the turbo blowing through it.. even put a very loud BOV on it and makes it go a little smoother

 

All he had to do was run a line from the propane carb to the condenser so that they had same pressure under boost.. can't remember where the lines were from though sorry..

 

We decided to and run the turbo coolant lines through the condenser so that the propane was warmed up enough..

 

And as for my EA82M build... I got everything together and put into my 87 and can't get it to fire up... I hate it right now lol

 

But will definitely let everyone know how it all goes(: hate being left at a dead end on a thread haha

 

 

Thanks everyone,

 

Galen (BoostedBoxer421)

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Boosted ...wow, I'd love to know just what mixer your friend used. Mine was a 200 also just a 90 degree elbow away from the throttle. I did also have a throttle body I Araldited an adaptor to for the mixer to bolt directly on top of the throttle body - feared the Araldite would go soft from the heat so never happened. I tinkered with the balance lines between mixer and converter (condensor), taking out any elbows to get a straight line and the smaller ID line I went, got better but still just not driveable beyond around the block! Admittedly though _ I did have a soft as marshmallow valve spring on one cylinder due to slack back sided head shop staff :( but all went good as soon as I went turbo draws through - my Guru did say to go this way in first place agaisnt what many Impco company people said. As sooon as turbo draw through also discovered that a vapour filled intake under pressure pushed a tiny amount down the dist vac line, through holed diaphragm got ignited by rotor spark jump inside cap, went pfft under light load or KABOOM about 2 or 3 psi and pushed - looking for fault :)

 

SkiShop did you mean to say the EA82T had a lower comp than EA81T ? We got 7.7:1 for EA82T, never got EA81T. Don't really expect a EA81 with EA82T pistons to be any more off a dog than EA82T on take off. Have to lower comp to avoid a ballistic event so EA82T pistons would be closest bet for safety surely ?

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skishop is excused :)

 

boosted - my ea82T is the early 85,86 version with separate knock control box and dizzy with innards rather than 'tronics, and the non spider type inlet manifold is said to suit propane better than the larger volumed spider design - thought to be closer to feeling fuel needs with lesser volume. It is dedicated so no afm, no fuel injectors or fuel pump in operation. The hook up was all done with various bends of silicone hose via ebay coming from China. I also used an exhaust shop to make up some size adaptors between the different sizes. My mixer, even though was a 200 had the larger sized outlet horn not by choice, only what I bought used and kitted up, not knowing it was the rarer one. My air filter box was a common old GM air box, flipped upside down and shoved into the spare wheel section that I then enclosed with sheet aluminium and rubber tailgate edge trim, topped to rub against underbonnet. Air came in via a few 30mm holes I drilled into the bonnet to feed directly into my created air chamber :)

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My gasoline EA82M will have the flat intake.. but when I build the propane version I'm going to use the high rise intake and modify its insides so that the propane doesn't condense in the large intake space(: or I may see about having a custom intake made for it

 

Also, my friend used an NA disty from an 87 GL and doesn't even use vac advance on his propane setup..

 

And are you running only propane?? Or do you still have gas and some electronics running?

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I have my doubts that you would get any propane and air mix condensing anywhere in the guts of a high rise intake - what with a turbo having just mixed it all up and preheated it ! Seen or heard of some amazing volumes between mixer and turbo and throttles over the years. I even run an NA with a 50 x 100mm rectangular box about 300 long atop a pair of twins with plenty or square inside corners for the mix to loiter - never any problems.

 

Once made an experimental on the dedicated EA81 with a massive efi throttle body off a 2300cc Ovlov coupled to the mixer by overpriced silicon bend and 50mm PVC plumbing pipe. Low speeds it bogged down overfueling or something, but once revs stayed up it pulled and cruised just like the twin carbs snorting propane. In the middle of winter I got an instant start the next morning no falling out of mix overnight or bleed off down intake valves.

 

I thought it may be due to the PVC not getting as cold as some other sort of ducting I have used before. Never got an instant start again so was not a defetc or such.

 

My original plan was to turbo an EA81 on propane only and to stake the dizzy so no internal advance, no vac advance and just an initial 16 DBTDC and see how that went - still to do list.

 

On your original question - a guy here added a turbo to, well, it was a running EA82 NA that just happened to have borrowed turbo heads at some stage, so was easy for him...set the initial timing at 10 degrees to allow for extra compression, ran on petrol/gasoline and reported good results on its strong torque. Some time later, car was up for sale for ages and had volunteered in the ad -a suspected spun bearing - maybe result of an old engine being boosted on NA comp ??

 

All my propanes are dedicated for no tuning compromise and only ran out and had to push and be pushed 300 meters when it ran out after 720km on one tank :)

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But you can't run a Blow-off valve with a draw through setup(: and I see there being some problems with large volumes of propane between mixer, turbo, intake, and heads when you let the throttle shut quickly.. plus there would be some delay on the mixer output between draw-through and blow-through.. haha if you couldn't tell I plan on making a Rally-X car that would need good throttle response and dependability

 

I would have rather used a carbed (8.7:1 comp.) for my gas set up, and use an NA MPFI (9.5:1) for propane

 

Thanks Jono, your making me already plan on getting a propane setup within the next month or so (:

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  • 2 weeks later...

So I've had the engine all put together for a couple weeks now and for some reason it will not start... getting fuel, spark, and everything is exactly how it was when I pulled the original engine.. only thing I can think of is that the computer is being weird or a timing issue, but I've been over the timing many times..

 

Jono, I believe that your issue with the impco 200 mixer is that it isn't the right size of mixer for one of these engines, the smallest size that seems to work is at least a 225.. the 200 probably doesn't richen up enough in regular driving (low end).. I've found that a 225 or bigger is a perfect match for these 1.8l engines. I'm looking for a 225 at the moment for the EA82M and will be looking for a 300 or bigger for my EJ22 swap in one of my other wagons

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You are the first to tell me that a draw through can't be assisted with a blow off valve set up ! Wish you were about when I tried so ! Could have saved me some coin and grief. I still plan on trying next time the engine is in something..thinking electronic blow up valve...after I have tried the return pre mixer. I know one guy whose dad did have a blow off and blow off working just his passengers complained of the smell - he was doin' an illegal blow off to atmos !!

 

My 200 was fine for 90 or 100,000km. The 225 is really not that much bigger in flow and uses same diapragems anyway. I run 125 and also have a 100 fitted up on NA EA81 twin carbs and spfi inlet manifolded jobbies. Seen a 225 on a 351 F100 belonging to a propane fitters truck of all things.

There are certain sweet spots for each size mixer and I get nice clean mixtures out of both sizes. My first 4 cylinder propane foray, my guru claimed the 125 can even do 3.0 Nissan sixes, yet every time I have seen one, they are done with 225 mainly due to the factory air intake duct sizes.

 

The 200 and L converter came off a 4100cc straght six.

 

OK, got it running now ??

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