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Is my Brat a dog? Underpowered?


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Howdy and hello all. I just got my 84 Brat smogged and on the road and I'm happy as can be. Just one issue, I feel like it's a dog. Doggier than it should be I suppose. Rebuilt the ea81 engine, valves adjusted, new fuel filters, Hitachi carb cleaned, float set at level(thought it was too low and causing lean condition), vacuum and mechanical advance working(though it was advancing too soon), timed at 9°btdc with 91 octane gas, egr working, oil changed(I suspected oil was too thick causing drag), no vacuum leaks, the cat is solid and good(thought it was clogged), everything seems to be perfect.

By the smog sheet at 15 and 25mph, higher nox, o2, and lambda at 1.2(not 1.0) shows me it's too lean, but adjusting float level, idle mixture, emission component operation, hasn't changed much of the performance. 

I'm used to driving my 2010 WRX so my basis for comparison is that unfortunately. Do these beasts take a calendar day to reach 60? Are they really that gutless? I'm looking for videos of people driving around to see if I'm crazy or need to enjoy what I got. 
I'm not getting a Weber, I'm in California and I'm fine with the stock setup.  I'll probably put up a video of myself driving so others can compare too. 
Thanks for any info the Brat vets can send my way. 

20220213_212914.jpg

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The problem is 40 year old technology trying to appease the needs of a seasoned WRX driver. 

The old EA81 isn’t a power house by any means. But it shouldn’t take a calendar year to get up to speed either. 

I drive mine with the foot in a bit, let it build the revs then go for the next gear. There’s no need to rush it with these! Sit back and enjoy the 80’a charm and the scenery going by between gear changes ;) 

I’m not sure that really helps you, but going from a WRX to the brat certainly isn’t helping you’re expectations of the little NA carb fed 1.8L donk with the tractor 4 speed gearbox... 

Cheers 

Bennie

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Stock, new and perfect the rig on had hp in the 80’s.   That’s maybe as much as 1/3 the WRX hp.

it is slow - someone described it once more lime driving a tractor than a car.  Embrace it.

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84 HP at the crank on a perfect engine. About 65 of that make it to the wheels (yes I have had them on my Dynojet). Vacuum secondary carb is lazy on throttle response. 

A 2010 WRX has the VF52 - factory tune is about 265 HP and about 220 of that makes it to the ground. More than 3 times the power. With added weight the WRX is ROUGHLY 3 times as fast. So a speed that take the Brat about 20 seconds to achieve will likely be done in about 7 seconds in the WRX. Count to 20.... one, one thousand, two, one thousand, three, one thousand...... yeah you starting to get the idea? 

Yes the Brat will feel unbearably slow. And frankly the Hitachi carb is a part of that with it's horrible throttle response. A 32/36 Weber at least gets you some torque down low and can take advantage of that long runner intake. 

GD

Edited by GeneralDisorder
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18 hours ago, el_freddo said:

The problem is 40 year old technology trying to appease the needs of a seasoned WRX driver. 

The old EA81 isn’t a power house by any means. But it shouldn’t take a calendar year to get up to speed either. 

I drive mine with the foot in a bit, let it build the revs then go for the next gear. There’s no need to rush it with these! Sit back and enjoy the 80’a charm and the scenery going by between gear changes ;) 

I’m not sure that really helps you, but going from a WRX to the brat certainly isn’t helping you’re expectations of the little NA carb fed 1.8L donk with the tractor 4 speed gearbox... 

Cheers 

Bennie

Powerhouse or not, I love it to be sure. It's been 15 years of me waiting to get a Brat, and maybe I'm just excited to plow through the gears and hit the trails. Thanks for the words of encouragement and realism all. 

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23 hours ago, Sasse said:

Stock, new and perfect the rig had hp in the 80’s.   That’s maybe as much as 1/3 the WRX hp.

it is slow - someone described it once more like driving a tractor than a car.  Embrace it.

 

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My main concern at this point is that it's running lean according to the lambda calculation.  I don't need power, I need reliability from future disintegration. I also short shift like an old lady.  With this being a fresh rebuild, I haven't let the revs get up to 3k until I'm sure this thing is the dogs nuts.  In watching somebody else drive, they get up to at least 3k it seems before shifting.  I'll just have to give it the beans.

Would anybody who considers their brat or other ea81-powered sled be willing to share their smog test sheet for comparison?  I don't want to run the long term risk of burning out the cat and in 2 years have the insanity of trying to find a new one.  Gotta love Cali cars.

I've considered converting the vacuum secondary into mechanically operated which can be easily undone if it doesn't work out in an attempt to eek out a little more oomf.

Thanks to anybody who can help.

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5 hours ago, DaveT said:

3000 RPM is too  low.  You're quitting just when you start to get power.  These are high RPM engines, not luggers / high torque low RPM.

 

^ with that said, low throttle at low rpm giving low engine loads is a-ok and I often drive around town like this while short shifting = justcruisinantakiniteasy ;) 

Cheers 

Bennie

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Hey you know there’s even slower smaller engined Subarus some of us sling around. We don’t mind cruising and yeah unless I really have to get going somewhere I’m that old lady too. Not much desire to go over 3k maybe 3500 , 4K once in a while. I’m driving in regards to my wallet and passive with my ego. 

Edited by moosens
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21 hours ago, moosens said:

Hey you know there’s even slower smaller engined Subarus some of us sling around. We don’t mind cruising and yeah unless I really have to get going somewhere I’m that old lady too. Not much desire to go over 3k maybe 3500 , 4K once in a while. I’m driving in regards to my wallet and passive with my ego. 

I'll make sure to speak well of those beloved ea71 engines also.  All Soobs need love.:)

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this could go a bit like " I get x miles per tank" , with people relying on judgement as to how much of the tank was actually used.

On my fully rebuilt EA81 with a 20/60 cam, on the highway, I managed 609 km from full tank to empty-I-ran-out-of-fuel in my 92 Brumby I think held 55 litres tank

This same build, running 4 sp DR box on standard 175/70.13 tyres allowed me to take off on tar with a squeal from the front tyres, then a chirp into second, and was about 18 seconds to a true GPS 100 kph (62mph) . Initial timing set at factory 8 DBTDC and I serviced the dizzy internals by pull apart, clean and inspect then greased all the moving parts. I also ran new plugs, rotor, leads and cap, new air filter. Yeah, I said 18 seconds :) Maybe check your zero to 60 mph and compare ?

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On 2/16/2022 at 4:20 PM, DaveT said:

3000 RPM is too  low.  You're quitting just when you start to get power.  These are high RPM engines, not luggers / high torque low RPM.

 

high rpm engines ? What engine are you using as a control Dave ? I think red line is 4800rpm on the EA81. What a grin on got in my control vehicle when an EA82 went in ! Control had run twin carb EA81 with L Series EA82 5 sp manual in a GEN ll EA81 body Brumby/ BRAT. So, it was not like comparing an EA82 L Series wagon to the EA81 Brumby.

When the first drive happened and I hit 4500 it was still quiet due to being hydraulic liftered not solids , and OHC instead of OHV. It just kept going effortlessly, up the rev range. I don't recall if it was this one, but one of my combo's of EA82 wound out to 6500 (must have been the turbo with big hole under the turbo :) More revs in each gear just meant that each gear had greater scope than the EA81 ever had

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Mostly Ea82.  They do fine turning 4k on the highway.  I skipped t he EA81 powered cars, my first 2 were a 1400 and a 1600.  I don't remeber the max Tom on them any more, but they did a lot better letting them wind up higher than I did when I got the first one.   Compared to the cars I drove before I got my 76, these engine are happier spinning  a lot higher than the V8s and straight 6s I drove.    I wore out the connecting rod bearings on that 1400 running it too low.  

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I never shift an EA81 before 4500 to 5000. The one in my t-cased hatch with 30" tires gets WORKED when I drive it up into the mountains. I've put it through miles of mountain climbing at 4500 RPM steady cruising.

They want revs under load - gives them better oil pressure. Lugging them will kill the rod bearings. 

This is NOT a chevy V8 or a diesel. If you want any power out of it you must get the RPM up. IIRC peak HP on the EA81 is around 3600 to 3800 RPM. 

GD

Edited by GeneralDisorder
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