chopsubie Posted June 2, 2010 Share Posted June 2, 2010 I see not many people are actively talking about their weber carb swaps, so I'll post this here because it is for a dedicated off road application. I recently built up an ea81, stock cam, stock bore, pistons, etc. I slightly ported the cylinder heads, and decked them ( about .007"). I plan on building some headers with 1-3/4" tube into one 2" with a decent high flow muffler. I will also add a 1-1/2" tube as a crossover as close to the cylinder head outlet as possible. All emissions will be removed, and the vacuum system will be reduced to a bare minimum.(alternator, brakes). I plan on using the hitachi 2bbl intake, but I may build a custom intake later(to separate the hot coolant and incoming air/fuel charge) I really wish I knew about delta camshafts back when I did this, and I will most likely be upgrading to one of their torque grinds some day. Anyways,Do any of you guys have a 38-38 weber on an ea81? If so are your cylinder heads, exhaust system, and cam stock? Is the 38/38 too big for the stock configuration? Is there enough room for adjustment on the 32-36 for both stock and higher performance set-up's? (I realize the ea81 is not a high performance engine, but is a reliable, dependable, and lightweight). Some of you might argue this is too much work and too much to ask from the ea81 design. I appreciate its simple design, just looking to get a couple extra pony's, and help it out on the bottom end some while maintaining or increasing it's dependability. Quote Link to comment Share on other sites More sharing options...
monstaru Posted June 2, 2010 Share Posted June 2, 2010 there is actually a weber thread at the top of this sub-forum... ...just sayin. cheers, brian Quote Link to comment Share on other sites More sharing options...
ezapar Posted June 2, 2010 Share Posted June 2, 2010 The 38/38 dumps too much gas for the ea81. 32/36 is the way to go. Quote Link to comment Share on other sites More sharing options...
chopsubie Posted June 2, 2010 Author Share Posted June 2, 2010 Since I have the engine assembled with the stock cam, I just ordered a 32/36. I just want to know if anyone is trying new things with the ea81, the VW guys are not scared to get 3x the Hp from their 1600cc h-4's. Quote Link to comment Share on other sites More sharing options...
NoahDL88 Posted June 2, 2010 Share Posted June 2, 2010 The VW guys also had the bar set much lower from the factory, and have aftermarket support. Why reinvent the wheel when you can drop in an EJ, fuel injection runs circles around carbs any day of the week. Quote Link to comment Share on other sites More sharing options...
chopsubie Posted June 2, 2010 Author Share Posted June 2, 2010 why not reinvent the wheel? If we all thought this way there would be nothing better than plain stock. No aftermarket options etc. Quote Link to comment Share on other sites More sharing options...
Uberoo Posted June 2, 2010 Share Posted June 2, 2010 (edited) what he is meaning is you can make EA81's that will make 100-120 HP.However you will have to spend a ton to make it happen.You would new heads that flow worth a damn,high compression,cam,ignition system,etc.For the money you spend is just better to put in an EJ series engine,140HP right out of the box,MPFI,and rock solid reliability. you can run a 38/38 on an EA81,it just needs to be built a little.32/36 is considered an upgrade on stock engines. the 1600cc VW guys that run a 38/38 have nothing going on until about 2500 RPM then they rev to 8 or 10K.the EA81 will spin about 8k if you have proper fueling.With a 38/38 it will be a dog until 2000 ish RPM then hang on. Most of the subaru guys like the low end grunt that the EA81 is famous for,because they go offroading or something.If however you want to spend alot of time at the higher end or build your motor go with the 38/38. Edited June 2, 2010 by Uberoo Quote Link to comment Share on other sites More sharing options...
NinjaTech Posted June 2, 2010 Share Posted June 2, 2010 You could look around at what guys putting EA81 engines into aircraft are doing. It really depends on how much power you're after too. Also ACVW engines have dual intake and exhaust ports so they have more potential to flow more air. They also bore them out to pretty big displacements upwards of 2.5L. Quote Link to comment Share on other sites More sharing options...
monstaru Posted June 2, 2010 Share Posted June 2, 2010 this convo is old.i would search around a bit.there are plenty of things to do to add power. the aircraft guys are mostly taking steps to ej there rigs now too.Ken built a 150 hp ea81.it is doable.but , regardless......the 32/36 can be jetted up quite a bit. all or most of it is in the weber thread.with alot of different links.that is why i stated it earlier....cheers, brian Quote Link to comment Share on other sites More sharing options...
chopsubie Posted June 3, 2010 Author Share Posted June 3, 2010 like I said before, I know the ea81 is not a high performance engine. I was just curious about others using the 38-38 along with other mods, and how well if at all it would perform. I too like the ej engines, however I have several ea81's & wanted to put one together to throw in an off road only buggy. I'm not expecting to rock out a 120hp ea81, just help it out a little bit. I do appreciate all the input and information you guys have here on the site. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted June 4, 2010 Share Posted June 4, 2010 People have used the 38 DGAS - virtually all of them agree that it's too large. Progression issues are rampant and the amount of fuel they eat is terrible - for virtually no gain. The 32/36 is large enough for small V6's so a little 1.8 is nothing for it. As to the VW comment - that's a completely different world. They don't have to deal with coolant and the cylinder jugs just unbolt from the bottom end. It's a much simpler operation to bore out or simply upgrade an air-cooled than it is to deal with the Subaru EA engine. About the only source of monster power for the EA81 is forced induction and about 200 HP is the reliable limit. Cost is prohibitive - $10,000 for a 200 HP EA81 vs. about $3,000 for a 265 HP EJ20G front clip from Japan...... GD Quote Link to comment Share on other sites More sharing options...
mcbrat Posted June 4, 2010 Share Posted June 4, 2010 what he is meaning is you can make EA81's that will make 100-120 HP.However you will have to spend a ton to make it happen.You would new heads that flow worth a damn,high compression,cam,ignition system,etc.For the money you spend is just better to put in an EJ series engine,140HP right out of the box,MPFI,and rock solid reliability. you can run a 38/38 on an EA81,it just needs to be built a little.32/36 is considered an upgrade on stock engines. the 1600cc VW guys that run a 38/38 have nothing going on until about 2500 RPM then they rev to 8 or 10K.the EA81 will spin about 8k if you have proper fueling.With a 38/38 it will be a dog until 2000 ish RPM then hang on. Most of the subaru guys like the low end grunt that the EA81 is famous for,because they go offroading or something.If however you want to spend alot of time at the higher end or build your motor go with the 38/38. I had similar results with a Holley 600 cfm on my built ea81. 2500+ it screamed, but below, it was a dog... I had it tuned enough to be a daily driver, but it wasn't as much "fun" as a stock soob.... this convo is old.i would search around a bit.there are plenty of things to do to add power.the aircraft guys are mostly taking steps to ej there rigs now too.Ken built a 150 hp ea81.it is doable.but , regardless......the 32/36 can be jetted up quite a bit.all or most of it is in the weber thread.with alot of different links.that is why i stated it earlier....cheers, brian I run 155 mains on my 32/36, but as I did stuff, the thing that made the most difference for me, was adding a MSD6A multi-spark ignition... my current set-up is: ea81 hydro block large valve heads ea71 pistons solid lifters delta cam ported and gasket matched intake at heads, and to the weber adapter. 32/36 with 155 mains re-curved distributor accel super coil (large block kind) MSD6a ignition NGK plugs gapped wider. (don't remember exactly how much) 8mm Accel plug wires and pushing my 35" tires, with the help of the sami t-case, and 4:10 axle gears, it feels awesome. Quote Link to comment Share on other sites More sharing options...
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