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What should an EA 81 with a Weber act like?


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I have a EA81 4spd in my 85 Brat.  It is really an older engine with the non hydro lifters.  I have all new everything on it, plugs, wires, cap, rotor, weber, clutch, fuel pump, you name it, I have gone through it.  (I bought it not running with a bad motor after it had sat a while so I just went through everything to avoid issues)   I have a 2 inch lift, 14inch tires with 10ply BFG's so they are a little heavy.  My main question is this:  Since I have only had bad motors in it since I have had it, what kind of performance should I expect from this on the highway?  Driving on good paved highway, while going up hills, I am lucky to top most hills above 45mph.  I am flooring it, even down hill, I floor it and the best I can get is 65mph.  Since I have never owned a "good" roo, I am not sure what I should be capable of.  Do you think the tires being heavy are that sapping on power?  I have never checked compression yet as I was told by a USMB member it was a strong engine when I bought it.  I am still planning on building the stock motor sometime but for now just wondering.  Oh, and also I get about 22mpg with the weber and it uses no oil.  Maybe I am missing something? 

 

Thanks for any suggestions and help.

 

 

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I am guessing you are running 195/75-14 BFG's. When I had 195 Coopers on my Brat it was 15% off on the speedometer. So your 65 would be closer to 75 if the same as my 87 Brat. There is variances from one to the other on many things. I would imagine that they are fairly heavy tires which would impact performance somewhat and kill a little more mpg. A Weber has instructions to set the carb right and if you got the model specific for an EA81 it should have the right jets. I would first verify the baseline settings externally and see what works best. If you still have doubt verify that the right jets are installed. I would think your mileage is low even if you added the 15% correction. Do you have a fuel regulator installed? It could be just enough pressure to override the float making it dump extra fuel. I think I have my regulator set for 2.5lbs. The extra returns to the tank via the return line at the separator filter.

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as stated above check the % that your speedometer is off so you can math out your actual mph.  same with the gas mileage, you have to add the extra miles to get the right reading.  getting 22-24 mpg isn't out of spec for your setup imo.  I think the stalling on hills and such is indicative of a small problem (probably carb tune).  it should be to hold most of its speed as long as your not climbing the sky.

 

id double check your timing.  A lot of people up the timing on EA82's, and someone may have attempted it on your EA81 which does not like it.  also check the fuel system and carb tune, it might just not be flowing enough fuel to keep its power up.

 

totally floored pedal isn't your best way to climb a hill when its already struggling.  try picking your toes up a bit. 

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My 84 wagon has its original 1.8, all tuned up, timing advanced as it can be without any pinging, a weber, and it does okay. Its no speed demon, by any means but its tolerable. And my average MPG is always between 24 and 26.

Those BFGs size for size, are about the heaviest tires around, so that doesnt help. And of course being larger than stock, the engine has less leverage with which to move the car along.

I had 195x75-14s BFG ATs on mine, and each gear is definitely "longer" than it was when it was still stock.

Now i have 205x75-14 hankook I-pikes on it, and its even worse.

But even with that, on level ground and no wind, I can get it to 80 on the speedo (90 or so after correcting for the speedo being off)

 

Throw in a windy day, or a steady incline and im stuck in the slow lane doing 60 (or less, depending on the hill).

 

Being a mechanical secondary carb, keeping it floored when its not spinning high RPMs is actually hurting your performance. It simply gets too much air compared to what the engine can use.

The rule of thumb i gave my wife to use is; if the RPMs are between 2k and 3k, use 2/3rds throttle. Between 3k and 4k, use 3/4 throttle. Kinda like that. Its imprecise, but gets you close to the ballpark.

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I don't usually floor it, in fact I only recently tried it to just see if it would pick up speed.  I can hear the carb open up when floored and know to stay out of it.  I realize the speedo is off, but base the fact on how many people are pissed off behind me as I limp to the passing lane if there is one.  I got a new compression tester today to see what the left bank is like on compression.  I know when I bought the motor, whoever owned it before me had modded it somewhat stupidly like using panty hose for a breather etc.  The thing has good power up to about 40mph around home on gravel.  It is just the highway.  I don't really mind too much as the attention I get is usually one of awe that a brat still exists and is pretty good looking.  Then I get a lot of offers to sell her.  Most people back off when I say 3500.00.  I think my carb is adjusted pretty well.  I used the instructions with my redline kit.  I do have an aftermarket fuel pump although am switching back to an OEM.  I am suspicious of my fuel breather lines and some of the lines removed and plugged when I went to the weber so I may try that again.  I have no regulator on at this time.  I just figured that flooring it on a down hill run should result in a little better than 65 with a 15% variance.  It just topped out and will not climb above 3200rpm.  Thanks for the suggestions, keep them coming. 

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Distributor centrifugal advance stuck?

Incorrect ignition timing?

Poor compression?

Plugged exhaust?

Dragging brakes?

 

Will it rev out strongly in the lower gears?

 

I`m thinking you should get more than 3200,at least downhill.

It is a subaru.You have to floor it.

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It revs out pretty good in low gears.  Today I got a new compression tester.  It is a good quality one.  My compression was #1, 145lbs; #2, 125lbs; #3, 150lbs and #4, 150lbs.  What should the compression be?  I put new exhaust on it but I wonder if I should check the cat.  We do not have inspections in Iowa, so I may "rod" the cat out.  The brakes are not dragging, I have new wheel bearings, cv shafts and brakes on the front.  Rear brakes are good with no drag.  Timing is okay, no pinging.  I am not sure about the advance stuck.  It was working fine when I timed it.  For right now, I am just wondering about the compression.  Mainly I am wondering on the 125lb cylinder.  Thanks for the help. 

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the fact that its lower than the others means something is going on with that cylinder, but thats not a horrible reading in and of itself.  id probably try some sea foam and see if the valves are just gunky (in fact, not a terrible thing to try and see if it revitalizes the power).

 

my vote is 

 

#1) timing or vac advance

#2) fuel issue or carb tune

#3) worn or weak ignition system.

 

 where is the vacuum advance on your distributer fed from?  it should be plugged into ported vacuum on the carb, not manifold vacuum.  shouldn't affect full throttle power either way cause theres no vacuum, but may affect light throttle applications.

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All good advice from above.  Basically from the factory the EA81 is going to struggle going up hills.  You can minimize it by doing a few things that have already been suggested above.  I will just put my list on here as well as to what i would do to check for things.  
 

-Full tuneup.  I didnt see if you had done that or not.  

-check vacuum advance on distributor.  Easiest way is to pull the cap off the distributor and pull the rubber line off as well and suck on it (no jokes!).  If it moves your good.  If not find another vacuum advance canister or full distributor.

-Timing.  When i had a webered EA81 i set my timing at 10 degrees instead of the factory 8.  It gave it a bit more oomfff but you would have to run decent gas...as in anything equal to or better than 90.

-Valves.  You have solid lifters so time to whip out the HTKYSA book and read up on adjusting valves.  If you havent done it would be good practice to do it.  Should take you about 45 minutes or less depending on your ability.  

-On the carb you should be running the fuel return line from the hitachi so no need for a fuel pressure regulator.  I never needed one running it like this.  

 

If this still is not to your liking and you would not mind spending a bit more money and pulling the motor apart a bit i have some suggestions that will not involve splitting the case.  

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I shift up anywhere from 2500 to 3000.  I did check the vac advance when I first put it in.  It was good but I will check it again.  It has new plugs, dist cap, rotor etc.  There is a slight sound coming from one cylinder which I was always worried about but the previous motor sounded about the same.  It is not a knock but more of a tick (closer to a slap that sounds like a diesel).  I just thought that was normal from the EA81 since I have heard no others.  The previous motor had a blown head gasket or something that leaked AF from the bottom of the engine on number 2 and 4 side.  I cannot say without looking but I do think I plugged the vac advance to the manifold.  I will have to check.  I did eliminate all the extra hoses from the hitachi and think it is plumbed okay.  There is a fair amount of blow out the oil filler when you pull it while running.  Enough to blow the cap off seat and up to the point it would fall off.  I timed it at 10 degrees the last time I set it but will check it again.  The distributor was kind of sloppy but similar to the other donor engine but I did switch it out at one point.  I was flirting with a new disty when I first swapped the motor.  The motor in it now was somewhat not too well set up as I said before.  The engine oil was black as diesel oil when I got it.  I will run some seafoam in her as well.  I did at first but that was a while back.  I still need to switch back to the original fuel pump.  I switched out the one before because it was surging and bucking.  It was putting out about 1gpm at best.  The one in it does fine but makes so much noise from the ticking that it is kind of loud in the cab.  I still want to freshen up the original 85 engine.  I took it out because the crankshaft was setting at an odd angle and the guy I bought it from said he forgot to put AF in it and broke the crank.  I have to get around to it later this summer.  I may bore it slightly and have looked at Clegg engine kits.  Thanks for the great advice guys.  Keep it coming....

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For these engines you should be shifting at higher rpm like 2,800-4,500.  I have a stocker and I usually shift around 3k, but if I am going up a hill I take it to 4K.  With more unsprung weight you would want to be in the higher portion of that range.

 

I would recommend putting the timing back to 8 degrees and shifting between 3,000-4,000 rpm, then gradually move the timing up until you hear the engine protest up a hill, it can sound more like a tick or rocker slap in these engines.

Edited by ferox
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Also sounds like you may not have vented the crankcase hoses properly. You shouldn't have that kind of base pressure if the motor is in good condition. It's dark and raining, plus I am getting ready to leave for work. And I can't off the top of my head remember how mine is vented. I installed my Weber maybe a dozen years or more ago. A quick search should show you if you have it correct or not. I will say that when I went from 195 Coopers on the steel pug rims back to 185/80-13 tires on the factory rims I noticed more difference than I thought I would accelerating. I am back to the pugs but w/ 185/75-14 Uniroyal's.

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I will search for routing of PCV and Weber.  I do say though that even with all the hoses unplugged from the valve covers, the cap still blows off.  Not way off, just enough to make it high enough that it will fall off the filler tube.  Also, when I had the 205-70-13's on it, it still was a dog.  I have tried to "plumb" it correctly but many different opinions exist on canisters, EGR removal etc.  Maybe I can take a picture of it.  I am not too computer savy.  I wish there was a step by step video for dummies!  I will do some searching.  Thanks again.

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Just went out to look at the Brat.  The disty is hooked correctly to the carb.  The oil cap will not blow off but just floats on the tube. 

 

I am still wondering about the distributor.  The shaft was wobbly but not terrible.  It is not eating caps.  I do remember once that one cylinder dropped out of firing and when I pulled the plug wire, it really showed no difference in the idle.  I think it was the bad compression cylinder.  I put it back together, wiggled wires and the next time I started it, the miss was gone.  I still hear a slight spitting in the exhaust. 

 

 

 

 

Here are some pics from my PCV routing, EGR block and fuel return lines. 

 

Brat Engine 1 shows how I hooked both valve covers, air box and PCV. 

 

Brat Engine 2 shows it again from a little farther back.

 

Brat Engine 3 shows my current fuel set up (temporary)  Do I need to hook the return line from the filter to the return line from the tank?

 

Brat Engine 4 shows the plumbing again from the other side. 

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The PCV breather routing you have is incorrect.

Just hook up all three (PCV, and both Valve cover vents)
to the hole in the base of the Weber filter.

You also have NO fuel return line coming from the carburetor.

Remove the single brass fuel fitting from the weber,
and replace it with the stock Hitachi fitting.
(which has provisions for a return line)

 

Connect the return line to the main shaft of the

The "Y" with the vacuum cap on it.

 

The curved side of the "Y" is proper.

Edited by Greenley
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Thanks guys.  I will get back to it soon.  Probably in a week or so. 

 

So on the return line, if I hook back into the main line of the "Y" fitting, where does that go when the ling goes into the firewall?  Should I leave the other line to the tank plugged like it is in the picture?

 

As far as the valve covers hooked to the filter base.  Right now it comes from the passenger side into the "T" with one small side into the breather, the other side splits off and into another "T" one side going to the PCV and the other to the other valve cover.  Basically it is all connected together but in a convoluted kind of way.  What do you suggest?  A "T" connecting both valve covers, then the third side to another "T" that one side goes to the PCV and the other to the breather?  It is hard to explain in writing but thank you for your help and patience. 

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you do not want all 3 ports hooked together.  you want clean air to enter on the passenger side valve cover area.  you can plumb it to the air cleaner or just get a breather cap, whichever.  the drivers side should go to the pcv valve.  you do want a small hose T'd in between the drivers side head and the pcv valve, but its only there to allow some fresh air in and reduce the suction on the drivers head.  again plumb i to a filter of some sort.  normally theres a small foam filter in stock air boxes so that these 2 hoses aren't pulling from the same air supply.  if theres no fresh air inlet then you won't clear enough bad gases out and if theres no air inlet between the head and valve then you will drink oil.

 

you mention replacing the fuel pump, are you sure it was for a carbed car?  fuel injected vehicles have a very different fuel pump stats.  webers are sensitive to fuel pressure, so check what the pump is putting out.  it should be very close to 3 psi.  you have a return line hooked up currently, its the second line coming off of the fuel filter in the engine bay (doesn't matter if its on the carb or filter).  what I don't know is if you have the tank vent hooked up correctly.  the 3 lines in the front are fuel in, fuel out, tank pressure vent.  fuel in is easy to tell, but you may or may not have the other 2 switched.  even if it is hooked up correctly your tank vent may be plugged off.  if so and you haven't changed gas caps to allow for some tank venting it can mess with your fuel delivery.

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Thank you so much, it makes sense the way you state it.  I do think that I may be pushing some oil out of the passenger side valve cover.  It is pretty messy and there really should be no reason for that.  I will adjust my hoses accordingly.  I will work on that today. 

 

As far as fuel pump goes, I have a NOS one ready to go back in as soon as I get a bay ready in the shop.  I don't want to mess with freezing in my non heated shop area.  The fuel pump I put in was a low flow Mr. Gasket from O'reilly's Auto parts it was rated to 3gpm.  My original stock unit would not put much more than .75 PSI out so I went to the Mr. Gasket one.  I always thought my plumbing was a mess from the fuel tank. 

 

So should the small 3rd line out of the filter (currently c clamped) should go to the plugged black hose (Not the blue cap, but the one with a bolt in it at the top of the c clamp area) which would be a return line?  What is the line that goes into the firewall?   

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Looks a little random there around your fuel filter :confused: . Try plumbing it like this: The weber in this pic is reversed, but you can see all the parts. The fuel 'y' fitting is on the d-side, hooked up to the carb on the opposite side. The other side of it goes to the top of the fuel filter. The only thing not visible here is the end of the tank vent line -it is the one sitting on the brake mc and the open end is just tucked in there. Hope this helps.

 

DSC02530.jpg

 

 

 

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  • 3 weeks later...

rrgrr, that picture needs to be a bit larger for him to see anything. I can;t stress enough about the shift points. When I first got my BRAT I was shifting betwee, 2,000 an 3,000. If you want power going up those hills, MASH that pedal to open up the secondary and keep the revs high.

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I can;t stress enough about the shift points. When I first got my BRAT I was shifting betwee, 2,000 an 3,000. If you want power going up those hills, MASH that pedal to open up the secondary and keep the revs high.

I was thinking that too. My 1st to 2nd, and 2nd to 3rd shifts are between 4k-5k RPMs, 3rd to 4th depends on what speed I wanna cruise at.

Ill disagree about just mashing the pedal though. Webers are "too big" for our application anyways, and being a mechanical secondary carb, its best to progressively open it up as the engine needs it.

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