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lightened pulley


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yeah thats what i figured, but i was just wondering if there was some universal bolt pattern or pulley size for some other subaru engine that might be close enough to the ea81, but thanks anyway!

 

Contact Garner on here! He was able to help me with my EA82T with a custom made pulley he made.

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Contact Garner on here! He was able to help me with my EA82T with a custom made pulley he made.

 

how is that pulley holding up anyway?? i wouldnt mind a new pulley, seeing as i only use 1 belt now, and i want to get some weight off the crank.

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yeah it would be nice to lose some of that weight, even better if u can run a single belt, which i might do cuz my AC comp is shot, i think i'll just rip it out. unorthodox racing claims u can gain 2.7 hp for every pound lost! it might just be marketing, but who knows, it'll deff feel better.

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yeah it would be nice to lose some of that weight, even better if u can run a single belt, which i might do cuz my AC comp is shot, i think i'll just rip it out. unorthodox racing claims u can gain 2.7 hp for every pound lost! it might just be marketing, but who knows, it'll deff feel better.

 

The pully will only save you maybe .25 pounds, so that would be a whopping .5 hp, at the crank, which would be nothing at the wheels.

 

I hate to be the bad guy here, but you're starting with a car that has 72 horsepower, there is nothing that you can do to it, short of ponying up real money, to make it perform decent.

 

Do a tune up, get good NGK plugs, the 1.49 dollar ones, there the best, gap em to .045 inch, which is a little bit more than the stock specs, get new wires, rotor and disty cap, and advance your timing to around 12 degrees BTDC, add a aftermarket ignition coil and you should have a more peppy feeling rig.

 

When you're ready to spend real money, you can throw on a weber, which when tuned right will make your low end responce feel a lot better than stock. Good free flowing exhaust will help also, but a complete set from head to tail will be pricey, the aircraft guys go with 1 5/8ths from the head, and once they merge they go with 1 7/8ths, it maintains good driveability off idle but helps with top end.

 

 

After all that, which will cost somewhere between 800-1200 bucks, you might top out at 90-100 horse power, and that is if the carb is tuned real well.

 

 

The lightened pulley is the least of your problems.

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yeah i already have plans to do the wires, coil, and disty from a 2wd model (subiemech artical stuff) and im getting the new exhaust done next week, going with 2.25 cat back, possibly hollowing out the cat, dunno yet. also changing the thermostat to a 175 deg to keep things cool. i was just wondering about the pulley cuz i wasnt sure how heavy the stock was, and i might want a single pulley conversion soon. im not dishing out the cash for the carb cuz i like the gas milage i get now and i dont really want to lose that. thanks guys, great advice.

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Mostly, light pulleys do some (not much, but *some*) good on engines that use a vibration dampening pulleys(heavy). The EA81 pulley is already very light. You would save virtually nothing in wieght, it would cost too much, and yeah.... just a wasted effort. Now if you were making a pulley for crank fired ignition, then you might as well try to make it light also. But that's a different scenario.

 

GD

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More free flowing your exahust is the less low end you have. It's really a question of do I want a offroader, or a street mobile... Compromises are almost pointless :(

 

If you lighten the flywheel, which on EA81's are very heavy, you'll feel like to have more top end. It will ruin your torque and screw up your idle though. I would really love to do up a EA81 just for fun. But really, old subies are cheap, and the cheapest form of more power is a EJ. :(

 

Somethings telling me to put that EJ22 in...

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Normally what you do is take it to a mechanic/machine shop and get them to lighten and balance it. Although I don't know how much you would want to lighten it. If you take too much off the car won't run, and there may be a point where if you over work your clutch you can warp the flywheel from the heat. You'd get a new clutch at the same time, unless your on a real budget.

 

I think it also messes with the timming, needing more advance?

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Lightening engine rotating parts just changes how quickly the engine will change RPM... in a Subaru, that means mostly when blipping the throttle while out of gear. The power-to-weight ratio of Subarus will make it unlikely that you could measure any acceleration difference. (The engine might feel more lively, though.) As already mentioned, it will adversely effect (how much depends on how light) your idle and low speed smoothness, and can increase clutch issues (grabbing, chattering). It does not effect combustion, so no timing changes are needed.

 

Lightening does not do any real world good UNLESS your engine's rotating masses are a significant total of your vehicle's inertia. BIG engine, light car, it makes a difference. Little engine, not-light car, almost no difference.

 

Re: Exhaust - Nothing much matters after the first major obstruction/restriction in the exhaust path. Low-end torque will not be adversely effected by a too-large pipe following a cat or muffler. All the old lore about pipe diamater deals with a straight pipe, where exhaust pulses and flow are not interfered with by a muffler. Exhaust pulses are reflected/dampened by every change in tubing cross-section and or reflective obstruction, so they never make it past a cat or muffler (even glass-packs mangle the pulse). Keeping a pipe small past the cat/muffler just adds flow restriction, and is not needed for "extraction" purposes.

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The twin belt pulley is heavier on the EA81 than some people may think. I pulled mine and had a mechanic at work help me cut the front pulley off, we then drilled about 8 or so 1/4" holes with a drill press. Total weight reduction was app. 1 1/4 lb. Performance wise can't really say but it seemed to make a small difference (been a few years ago that I have done this).

 

Ram engines that makes EA81 aircraft engines sells a lightened underdrive EA81 pulley, don't remember the weight or price but a search will turn that up for you. Probably not worth what they would want for one unless you have extra cash to burn.

 

Glenn

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Re: Exhaust - Nothing much matters after the first major obstruction/restriction in the exhaust path. Low-end torque will not be adversely effected by a too-large pipe following a cat or muffler. All the old lore about pipe diamater deals with a straight pipe, where exhaust pulses and flow are not interfered with by a muffler. Exhaust pulses are reflected/dampened by every change in tubing cross-section and or reflective obstruction, so they never make it past a cat or muffler (even glass-packs mangle the pulse). Keeping a pipe small past the cat/muffler just adds flow restriction, and is not needed for "extraction" purposes.

 

 

thank you. that was my first thought when i finally learned about the whole extraction thing.... any expansion chamber would act almost as a capacitor or damper to even that all out.

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Hope you don't really want low end torque, cause with exhaust that big your gonna loose it.

 

i'm not an exhaust expert but i've put larger exhaust on an XT6 which has a much larger engine (2.7 liter 6 cylinder) and 145 hp stock and i even think 2.5" is too larger for that. i think 2...maybe 2.25" depending what you're after is more than adequate on those. i'd think 2" or 2.25" would be maximum you'd want for normal applications on a 1.8 liter subaru. but again, just talking from experience, i don't know much about exhaust theory.

 

i agree with all the comments on power too. i've done all sorts of things to the 145hp 6 cylinder ER27 engine in the XT6. exhaust, removed A/C pulley, ignition upgrades, intake modifications, new hewgaskets and valve job, perfect compression, play with timing, synthetic fluids...blah blah blah. alot of that stuff adds to reliability or needed replacement anyway, but in the end you don't end up with tons more horsepower. very little difference really, even on a much larger and more powerful engine than the 1.8 liter. old non-turbo subaru's are not power houses by any means. i wouldn't spend too much time on trying to make it powerful. if you really want power, then start planning ahead for a turbo or a complete newer generation swap. read through all the EA82 and even ER27 posts about modifications and you won't see great results. lots of effort and time on little return really.

 

but..there has been lots of awesome work done and i highly recommend reading about it including looking at some good dyno results all through this forum. i highly value these vehicles, but not as powerhouses.

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