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More Power from 1984 1.8L


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Greetings

 

Any suggestions on how to get more power (20-30 HP) from a 1984 1.8L in a wagon??

What's this I hear about parts interchangeability between a certain type of Porsche engine and a sub engine???

 

Thanx

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Nippondenso distributor off 2wd.

 

Wives tale - doesn't change a thing. They fit better with the Weber, but that's all.

 

84 will already have the large intake valves - so your engine is 74 HP stock. Weber and better exhaust from the y-pipe back will help - probably worth about 2-3 HP. It feels like more by "seat of the pants" but it's not. The progressive linkage, and larger main barrel the Weber gives it a more sporty low-end. Top end is almost unchanged. You can get nearly the same effect (not quite as good, but WAY cheaper) by wraping a bit of coat hanger around part of the linkage in the Hitachi to give it a progressive opening like the Weber. Still - the Weber is easier to work on, more rugged and reliable. Not to mention a lot simpler.

 

If you want 100 HP, you need to port and deck the heads, change the pistons, and most of all - change the cam, and recurve the disty to match. Mileage will be crap, but you can get there. You are looking at about $500 in parts to tear it down and rebuild it to 100 HP specs. That's assuming you do it yourself.... there's a couple special tools needed to split the block as well but for a one off you could make do with a coat hanger and cheap auto-parts store junk.

 

140 HP is possible, but will cost you about $5k in parts. It's done for the experimental aviation community all the time, but they pay $10k for an engine and are ecstatic about how "cheap" it was. They make custom dual port heads (milled stock heads - TIG welded intake flanges, and flow-benched...), dual plug ignition systems, custom MPFI intake, extra powerful lubrication, etc, etc.

 

GD

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I totally agree with the EJ swap for street. I plan one for myself in fact.

 

My beef is off the street. Not really the belt itself - the tensioner and ilders and the general lack of easily maintained accesories. Water,Mud,Dirt and dust just don't mix with the timing belt system, and I don't see that changing.

 

GD

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1600, EA-71 pistons are a direct swap

 

Delta regrinds the cam for less than 100 bucks

 

Philbin in Oregon recurves distys for less than 100

 

84+ heads are hydraulic, and have bigger valves, those are the ones you want. you can't mix hydro heads with a solid block, at least it didn't work for me.

 

Webber on top, 32/36 DGEV get the electric choke, much better than the water choke.

 

Free flowing exhaust, no bigger than 1 7/8'ths after the header or you'll have absolutely no bottom end, this is what the Aviation guys run, and i tend to believe them.

 

If you are feeling real ambitious, put the EA-81 disty gear on the EA-82 SPFI disty and make it SPFI, not as good as the EA-82, but it'll run 100 times better than with any carby, downside is you need to do a wiring harness conversion

 

I'd personally go for the EJ22 swap, its no walk in the park, but its easy enough that with a few extra hands and a wiring diagram you can figure it out. I've had an EA-81 wagon with this swap and it was super quick, and i still have an EA-82 wagon with it, and i love it.

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Question about this philbin place. Is their a phone number to contact them and what kind of information would i have to provide to them for the recurve (i already have a reground cam). Another disty question at the same time. At one point i pulled a disty out of an 81 2wd ea-81 wagon, to put into my 83 4wd wagon. The shaft seemed a hair to big and it wouldnt slide into the hole. From what i have read it seems that it is a good chance that the 81 2wd's disty would be a nippon denso unit, If this is true (how does o ne tell?) are all the shafts slightly larger on these units compaired to the hitachi's?

Ive collected a hydro long block, weber, reground cam, and some ea-71 pistons and am looking to build my self a little monster. Also any advise on tube size for a new y pipe, I'll run 1 7/8 to a glass pack, no cat, the rest of the way. I've also read that an ea-82 intake manifold will flow a hair better, any point on trying to smooth it out.

Thanks for the help

David

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www.philbingroup.com

 

Distributors are all the same shaft size - EA71, EA81, and EA82. Brand doesn't matter. 2WD and 4WD are the same curve. Use whichever one you like, but note the ND fits the Weber choke better.

 

EA71 pistons are almost not worth the effort unless like me you had to actually pull a set to measure them and compare against the EA81 pistons since no one else on this board bothers to check their numbers. They are about 15 thousandths taller.... or the wrist pin is that much lower. SPFI pistons would be a better choice and easier to find. The 1600 ones will work, and will increase compression slightly, but the rings and ring lands are smaller, and weaker. I'm hoping this is not a problem - especially since I'm not going for more than ~100 HP.

 

I'm going with SPFI and EA82 y-pipe (already has the O2 sensor as well) for my build. The MPFI EA82 is good for 95 HP, and that's about what I expect to get from the EA81. 100 HP or so. SPFI will scale to that easily, and the EA82 y-pipe will flow fine for those numbers. Reality sucks, but without major head modifications or forced induction the EA81 is not capable of more than 100 HP. Getting from 74 to ~100 is a pretty big accomplishment when you think about it.

 

As for all this OHC talk - yay for all you folks. I'll laugh when all your belts and bearings lock up and eat themselves in the mud. I have enough problems with my power steering idler, and alternator bearings.

 

GD

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sohc and dohc beat ohv any day of the week
... Hmm, I wish you were in Aus so I could show how a properly built EA81 push roder can go. I have the dual carb EA81 with all the dual carb goodies, better cam, EA82 styled valves arrangment, and two carbs. In stock, new, form it should do about 104hp. Freely revs to 7500rpm. Is a sweet engine.

 

Oh, and BTW, drag engines get over 2500hp with push rods... :) I don't think a timing belt could take it (other wise you'd expect to see them on drag cars.)

 

It all depends on the build of the engine. The fact EA82's are more powerful then EA81's is because of the restrictions in the air flow. Give a EA81 the same flow as a EA82 (i.e. the EA81dc), and there no different to each other for power. It's just the fact that a normal EA81 is older and not as refind as a EA82.

 

As for the topic, seems in the US you can get EJ22's in junkyards, I'd probably go the swap. Unless you don't like working with cars at all. Then I would get a 2.5" exhaust with straight thru mufflers built at a exhaust shop. I'd get a pod filter with some adaptor fitting to fit the carb (not hard at all, I've done it.) And some new spark plugs and wires, with a new disty cap+rotor. Oh, and if you pour a little bit of AUTO trans fluid down the carby when the engine is running, slowly of cause, it can do wonders. Good clean out always helps.

 

Of cause theres always more you can do, it just depends on how much money you have, and if you like working with cars.. And I don't mean doing things like oil changes...

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Well at a starting point of 74hp a 15hp gain is 20%, that seems like a lot to me. Im just looking to turn my 27"ers up a couple more hills with out having to down ship. FI seems like a soild idea but a little to much work for me right now, i alread have my weber attached to a cone filter so that'll have to do. I also plan to strip as much weight as i can because that can only help. I cant wait to hear this engine run.

Thanks for the advise.

David

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Im just looking to turn my 27"ers up a couple more hills with out having to down shift. David
Currently I have a box-stock EA81 in my '84 Brat with a slightly larger free flow exhaust and and weber. Added to that I have a 5 speed d/r conversion gearbox. With that, I have no problem running 65 to 80 mph and up on the highway; car goes uphill (South Center I-5 hill) with two 200+ pound people in the car and about 500 pounds loaded in the back at 65 mph without downshifting from 5th gear. The weber, gearbox and exhaust are all easy and relatively inexpensive. Car runs just fine with that. Drop me a PM and I'll send you an address and 'phone number. You can drop by on the weekend and drive it since I'm right next store in Bothell.
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See this Link:

http://www.ultraflight.dk/subaru_ea-81_performance_parts.html

So, you got two roads to choose: Upgrade your EA Engine, or Swap an EJ Engine. The option is Yours. Good Luck!

 

I looked into those heads as well as the Ram Performance heads a while ago and teh SUB4 heads cost ~$2000 with four ports while the 3 port Ram heads were ~$1500. Maybe some day when I have the money...

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Miles - you rarely keep a car/engine long enough to find out :lol:... and do you even *really* have mud in Indianna? :rolleyes: J/K

 

It's not just that they are replete with bearings of all shapes and sizes, it's how much easier the whole front of the EA81 is to work on. Sure - without the covers you *could* replace the belts quickly - even in the mud, but who wants to have to do this? Not I.

 

It's all preference really. Some people prefer Jeeps too - are they wrong?...... yes they are, but they just haven't figured it out yet.

 

People (lots of people - myself somewhat included) are also very apt to defend the stuff they already have - admitting that your car/engine/whatever choice wasn't the smartest is hard to do. I like the EA81 because I have two EA81 vehicles, and plenty of backup engines and parts. That in itself is a big factor. I have an EA82 as well and it runs very well - I just don't like working on it as much..... and I just can't see those belts running UNDER muddy water and doing it reliably for a long period. I enjoy deep water on occasion (well - "on occasion" actually works out to be every chance I get, so maybe more often than that), and having a belt idler chew itself to bits a mile down the trail is just NOT cool. One less thing to worry about in my opinion - actually five or six if you count all the parts I don't worry about on my trail unit :rolleyes:

 

GD

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What overhead cams bring to the party is the ability to run the valves predictably at higher engine speed. They do not "increase power", just the ability, if taken advantage of, to provide better breathing at higher RPMS. The short stroke means short pushrods on the EA81, so not much difference in valve accuracy with max RPMS that we are likely to run.

 

The real difference in power potential between the EA81 and EA82 (US spec, at least) is the combustion chamber shape: Bathtub vs. wedge. (vs. pentroof in the EJs...) Valve size and shrouding, port shape all come from CC shape.

 

No reason you shouldn't get 100 BHP/L from either engine... higher compression, wilder cam timing, better breathing, spin it faster. But would you want to drive it on the street? One of the qualities of the EA engines is their torque curve, and to get real power you have to shift that curve up the RPM range and make it peakier.

 

BTW, what I would like is an EA82 or EJ22 with chain-drive for the cams. Sealed, reliable, durable. Noisier, more expensive than a belt to manufacture. But my Datsun has 300k on its chain...

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BTW, what I would like is an EA82 or EJ22 with chain-drive for the cams. Sealed, reliable, durable. Noisier, more expensive than a belt to manufacture. But my Datsun has 300k on its chain...

 

While this may seem like a good idea at first...... you have to remember the cam and crank seals, plus the water pump and oil pump are all inaccesible without the timing "system" (whatever you use) removed. While the chain may last 300k, the water pump will not, and the oil pump will need at least a reseal - likely a replacement sometime after 200k.

 

GD

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While this may seem like a good idea at first...... you have to remember the cam and crank seals, plus the water pump and oil pump are all inaccesible without the timing "system" (whatever you use) removed. While the chain may last 300k, the water pump will not, and the oil pump will need at least a reseal - likely a replacement sometime after 200k.

 

GD

Details...details... :rolleyes:

 

I would like it it... I didn't say it would be easy (or practical).

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