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Plugging vaccum lines?


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So i read here and there that people are plugging their vacuum lines and it helps their power? My wagon is just my beater so any extra power here and there would be awesome. I'm not sure if im mistaken or not though. What in particular should i plug? Thanks for any help and sorry for the vague question.:confused:

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So i read here and there that people are plugging their vacuum lines and it helps their power? My wagon is just my beater so any extra power here and there would be awesome. I'm not sure if im mistaken or not though. What in particular should i plug? Thanks for any help and sorry for the vague question.:confused:

 

Thi applies motly to Carbed models. And it isn't that the motor will make any more power. It is that old emmisions sytem develope leaks which cause poor idle, hesitation, and rich/lean mixture in some cases.

 

Eliminating a broken and hard to replace/service part eliminates the problem. And makes the engine run better. Not nessecarily with any more power. Just smoother and more driveable.

 

I myself make every effort to repair and maintain all my vaccum hoses and accesories. But sometimes it just isn't practical. I would not jut start ripping off vac lines to gain power. Won't happen.

 

Besides, with FI, there really aren't many *extranious* vac lines. It pretty much all need to be there. Leave it alone and do a tune-up*. Much better way to make it run nice.

 

*Complete Loyale tune-up:

plugs

wires

cap

rotor

fuel filter

airfilter

pcv valve

 

Replacing all Vac hoses is a good idea too

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all the vac lins can be removed, if you have the intake off the whole metal vac line system is removeable as one piece, and you would connect the cabin vacuum from the firewall to the nipple on the intake itself.

 

although i dont recommend this unless something is broken or you are building legos.

 

i stripped my sedan's spfi and it could stand to run better.

 

anf anything you eliminate it could be the egr or purge control, but only if those systems dont work anywy.

 

althoug it looks like a rat's nest, the spfi vac system is rather simple

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all the vac lins can be removed

 

That simply is not true. The fuel pressure regulator vac line cannot be removed and still have the SPFI run correctly.

 

Besides - he shouldn't be attempting this till he understands what each of these devices does, and what he is potentially losing should he remove them. There are pro's and con's to each.

 

Also you aren't going to get a single ounce of extra performance for your trouble. So unless you just like things to look clean, you shouldn't touch it.

 

GD

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Hi all, first post! :clap:

 

Last March '07 I bought what was originally an '83 GL 4WD 4-speed but over the years has turned into a Frankenstein of parts. I bought it from a former ice racer and I use it exactly for that...Ice Racing!

 

Anyways, I'm watching this thread with interest as I'd love to make the ol' EA81 engine a little more reliable.

 

You all seem to know your stuff so I hope I can learn a little something here and there.

 

Here are some pics: :headbang:

 

n546021277_873626_4414.jpg

 

_MG_8857.jpg

 

IceRacer202-1.jpg

 

Thanks!

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now that's a cool car!

 

I found somewhere in here a pic a guy took of his ea81 that had all lines plugged and I run that way now too.

Like mentioned before though, it won't give you more power just eliminate any vacuum leaks from your 25 year old emission system.

On a newer fuel injected system there is almost nothing that you should plug off, even the egr, leave it alone if you want it to last.

 

BUT on the ea81 THE ONLY LINES YOU REALLY NEED ARE THE FOLLOWING

 

Cabin vacuum- for the heater controls, long vac line out of the firewall, can't miss it.

 

PCV Valve- anyone who tells you you don't need this is a blubbering boob.

 

Brake vacuum hose- brakes are no fun to use without SOME help

 

Distributor vacuum advance- tells your ignition timing to advance when engine is under a load = more power. I connect this to above throttle port vacuum left side tube, bypassing the thermo vacuum switch wich switches the vacuum from manifold when cold to above throttle when warm (just another connection and part that can and does go bad.

 

I've been running like this for awhile now, doin great.

TAKE SPECIAL CARE IF PLUGGING EGR THAT YOU GET IT TOTALLY PLUGGED

 

and be aware that by design the egr system is supposed to cool your valves and reduce emmisions

 

old cars carbed, plug away

FI- don't be ridiculous Balky......

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OH HEEEEY 1 more thing...

 

Your secondary throttle on an ea81 hitachi carb is activated by vacuum, if you have a major leak it won't work turning your car into a 1 barrel.

 

I say this mostly for iceracer. plug all the stuff and check this out, I've done it and it works great! At first I had a problem with it sticking open but a small adjustment to the .02$ wire fixed that. (it would flood and be hard to start)

But if in question check out this thread:

http://www.ultimatesubaru.org/forum/showthread.php?t=49976&highlight=secondary

 

If you remove the secondary diaphram like I did be sure to seal the hole or you'll make a vac leak.

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