New here, I have searched some but havent found what I want.

Basically...why switch to the weber..I imagine increased perfomance/reliability?

 

What does it do to your MPG?

 

How much HP increase can I expect?

 

Am i better off buying a complete kit (seen them on ebay for $320) or piece a kit together?

 

Thanks guys!

Edited December 17, 201015 yr by aaronxs400

New here, I have searched some but havent found what I want.

Basically...why switch to the weber..I imagine increased perfomance/reliability?

 

Better low-end torque, throttle response, etc. Easier to maintain, simpler, and more reliable.

 

What does it do to your MPG?

 

Nothing if you tune it properly and drive the same as before - chances are you will hot-rod it a little more though and lose a few.

 

How much HP increase can I expect?

 

None - the carb isn't the bottleneck at the peak HP RPM range.

 

Am i better off buying a complete kit (seen them on ebay for $320) or piece a kit together?

 

You are much better off calling www.carbsunlimited.com and telling them what you want - electric/manual choke, air filter height (short for stock height rigs, tall for lifted rigs), adaptor plate, manual choke cable if applicable.... etc.

 

Thanks guys!

 

Sure.

 

GD

I have found over the years that port matching the adapter to the intake gives even better performance and fuel economy. Some have even mentioned increased mpg if you can stay off of the right pedal.

 

The debate of whether or not there is a HP increase goes on and on. Simply because no one ever dyno's an EA81 It feels llike there is more power because of the improvements to throttle response and a longer powerband. Better air flow into the carb as well helps to achive a better tune.

 

I agree with the recommendation of carbs unlimited. They have always done a great job getting the proper jetting and throttle adapters for the Subarus.

 

There are many installation threads that can answer any questions or problems that may arise.

I obtained my Kit at: http://www.webercarburetors.com/ and Still is Workin' Awesome after almost five Years of Rude Use.

The debate of whether or not there is a HP increase goes on and on. Simply because no one ever dyno's an EA81 It feels llike there is more power because of the improvements to throttle response and a longer powerband. Better air flow into the carb as well helps to achive a better tune.

 

Dyno! Someone dyno before and after carbs.

Dyno! Someone dyno before and after carbs.

Not going to happen because of cost and time considerations. Ask a shop that has a dyno what they charge to put your Brat (or early GL) on there. Then take the time to change over the carb and then pay again to put it on a dyno again. Two dyno sessions will cost almost as much as a weber conversion all by itself.

 

That being said, I've done three weber conversions to our Brats over the years and have never been unhappy with the result. The weber is less problamatic than the Hitachi and it's such a joy when that secondary opens. I've never felt a dyno run was required to appreciate the improvement with the conversion.

Not going to happen because of cost and time considerations. Ask a shop that has a dyno what they charge to put your Brat (or early GL) on there. Then take the time to change over the carb and then pay again to put it on a dyno again. Two dyno sessions will cost almost as much as a weber conversion all by itself.

 

That being said, I've done three weber conversions to our Brats over the years and have never been unhappy with the result. The weber is less problamatic than the Hitachi and it's such a joy when that secondary opens. I've never felt a dyno run was required to appreciate the improvement with the conversion.

 

I can get local dyno runs done for $70 a run.

I'll agree with everyone the thrill of the secondary opening is great! Sure seems like more power.

I can get local dyno runs done for $70 a run.

 

Looks like we have a volunteer...

it will be spring time before it can happen, but im willing to do it.

 

question:

 

can you keep cruise control?

it will be spring time before it can happen, but im willing to do it.

 

question:

 

can you keep cruise control?

 

Depends on whether or not it is dealer, factory or aftermarket installed. I would imagine you could retain it. May have to get a little creative with the linkage but it can happen.

factory installed as far as i can tell. but if i go with a 5 speed swap then i pry dont need it.

Looks like we have a volunteer...

I don't want to rain on your parade, but you have to have at least two dyno runs (one before and one after) to make any quantitative comparison. And then more runs if you wind up re-jetting the weber for optimum performance.

No rain here...ive been drag racing motorcycles since i was 16...i know what a dyno tune consists of lol.

 

ill do one in the spring before the weber swap. ill do a second one after the weber swap (pry on a different day, but ill try to get the weather as close as possible using my weather station) and ill see how the a/r curve looks and possibly rejet.

couple more questions for you guys.

 

How do i know what carb I have from the factory without tearing into everything?

 

What manifold do I need to run? EA81 hitachi, ea81 1bbl, or ea82?

 

Has anyone ran a pair of motorcycle carbs on an ea81? Im a motorcycle mechanic/racer and am use to the stuff.

one more....

 

how/why does coolant flow through the manifold?

 

how many coolant inlets/outlets does the manifold have?