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Rebuilding EA81; can I delete vacuum?


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 I'm still a bit of a novice when it comes to car engines, but something I am seeing that I don't like is a whole bunch of cracked hoses that scare me. Some of them have even been cut and capped by the previous owners, during my engine removal I found a hose that was just straight up capped on one end and unattached on the other.

 So my question is how hard would it be to just do away with a majority of the vacuum system and replace with aftermarket electrical parts? One idea I had was building something like an MSI MSD platform thatway future upgrades (EJ22) might be easier. Something also to note is that I'm not putting back in the AC/Heat system at all. 

Edited by Guy_Rucker
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 Completely worth the Webber Carb, i know $300 is alot, but once you crank on the vehicle and it starts right up with little tuning, it will completely bring a smile to your face like it did to me, the hardest thing about the install of the carb was removing all the emission nonsense.

 

also keep in mind, that original Hitachi carburetor is made to function correctly with the emission crap on it, that probably isn't even working anymore after almost 40 years, removing them and making that Hitachi Carb is a matter of luck, like Sapper 157 mentioned, get a New Carb, don't forget about the special adapter plate for your manifold, and a new gasket to your manifold.

Edited by Subasaurus
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If those are the only real considerations than I feel pretty confident. I forgot to mention that I ain't ever seen the Hitachi carbs, theres a webber on there already. Actually now that I'm typing this it kinda explains all the capped hoses.... Well then I guess its just to planning out my build then. I've heard good things about MSD but thats about all I know, any other pointers when replacing electrical engine systems? 

 

 

 I guess to be a bit more indepth I suppose I should say my plan as it is at the moment. 

 So far I've removed the entire electrical bundle and rolled it all the way back to the firewall, on the inside the dash and vents are out, but the electrical is still together. Everything is out of the engine bay right now except for the brake system, steering system, and transmission (And I mean everything, brackets and all), and all that I want to go back in is the engine, D/T, brakes, neccesary stuff, ect as well as the most minimal wiring possible. I don't want to invest too much into the engine for now since I plan on upgrading the BRAT into the EJ22 later on in life. But if you're telling me all I gotta do is cap and plug most vacuum hoses then thats pretty neat. I'll dig up a wiring diagram and just rebuild with the parts I got for the EA81.

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Using MSD components will net you NO gain on an EA81 as far as power is concerned. They also won't help with a future EJ swap. To do the swap, you need the engine, wiring harness and ECU to make it run. Without it, it won't and no amount of MSD add-ons will make it run. You also really won't gain anything using them on a stock EJ platform either. The whole purpose of upping your ignition voltage is to overcome flame out at the plug caused by high compression with a lot of fuel. EA & EJ platforms don't run anywhere near this in stock form. Now, I'm sure someone will say, yeah, but you can use it for timing control. True you can, but the EA81 has no knock control at all, so bumping the timing leads to melted pistons. On the EJ platform, it has knock control, so any advance you try to add will be pulled back by the ECU to prevent spark knock. So again, really no gain for a stock engine.

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If it has a Weber then there should only be the pcv system, distributor advance, brake booster. That's like 6 hoses. Cap or even better seal all with some jb weld aluminium putty. Msd ignitions are great, on old hotrods which our subys are far from. if planning an event swap, save and buy a stand alone if you concerned that much. Ej22 can be made into beast engines with tuning. But also they are expensive as platinum to get power out of. A stock ej with bolt ons can net 160hp. That's nearly double the ea81 and ea83 engines. That's plenty of power and torque for our mid 2000lb cars

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If those are the only real considerations than I feel pretty confident. I forgot to mention that I ain't ever seen the Hitachi carbs, theres a webber on there already. Actually now that I'm typing this it kinda explains all the capped hoses.... Well then I guess its just to planning out my build then. I've heard good things about MSD but thats about all I know, any other pointers when replacing electrical engine systems? 

 

 

 I guess to be a bit more indepth I suppose I should say my plan as it is at the moment. 

 So far I've removed the entire electrical bundle and rolled it all the way back to the firewall, on the inside the dash and vents are out, but the electrical is still together. Everything is out of the engine bay right now except for the brake system, steering system, and transmission (And I mean everything, brackets and all), and all that I want to go back in is the engine, D/T, brakes, neccesary stuff, ect as well as the most minimal wiring possible. I don't want to invest too much into the engine for now since I plan on upgrading the BRAT into the EJ22 later on in life. But if you're telling me all I gotta do is cap and plug most vacuum hoses then thats pretty neat. I'll dig up a wiring diagram and just rebuild with the parts I got for the EA81.

Again, I am unsure what vac ports you’re talking about. If you have a Weber (only one “b” please) then you should only have one vac line coming from the front of your carb to the distributor. All other vacuum ports on your intake/engine can be capped. As far as MSD, I can only repeat what has already been said... there really is no gain to adding MSD to an EA81

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Again, I am unsure what vac ports you’re talking about. If you have a Weber (only one “b” please) then you should only have one vac line coming from the front of your carb to the distributor. All other vacuum ports on your intake/engine can be capped. As far as MSD, I can only repeat what has already been said... there really is no gain to adding MSD to an EA81

 

Guessing he's got the Carter-"weber" single barrel carb from an 82 year engine.

 

Guy-Rucker, I would spend time learning about what vacuum systems do.  Research "air bleed" and "Emulsion tubes" and carb theory in general.

 

Ripping off systems willy nilly will likely lead to problems for you.  Books are awesome.  Like from the library, read old carb books.

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Thanks for all the input, guys! Knowing to not waste my time looking into MSD is as helpful as being told to look into the air bleed and emulsion. Now that I have an idea of where to start looking I'm gonna do just that! If I have any more questions about vacuum I'll be sure to bring them up here. Thanks again! 

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