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ea82 carb , can work with turbo???


erez
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hey , I have an 87' GL wagon 4WD manual. with hitachi carb

I want to put a turbo, inside,

it is possible? in any way?

I think maybe to put the turbo after the carb'

 

I cann't exchange the original engine because in israel the EA82 turbo or the injected , are not common at all, only a few 1800 carbed,

thank you all

Edited by erez
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While it's possible to turbocharge a carb, it's a mess to do it. Carbs work on principles of differential pressure, venturi, emulsion, ect. When you start changing the incomming air pressure these things change dramatically and some of them break down entirely. There are two basic types of carbed turbo setups - blow-through and draw-through. Both have advantages and both have severe problems as well.

 

1. In a blow-through setup you push air through the carb. This changes the pressure inside the carb to higher than atmospheric under boost. There are all kinds of problems with this setup:

 

a. Either the carb has to be very well sealed, or has to be contained inside a pressure vessel. It's generally easier to just put the whole thing inside a sealed box and avoid spraying air-fuel mixture out of your throttle shaft bushings when the boost comes on. :eek: The Maserati BiTurbo used this method.

 

b. Fuel pressure has to rise linearly with boost pressure. Otherwise the float bowl will not be a consistent level or the boost will just slam the needle shut against the seat and you'll starve for fuel.

 

c. Because carbs are designed around differential pressure, and you are cahnging that with the turbo, you will have a very hard time tuning the carb to run well both on and off boost. In the case of the Maserati they used a sequential turbo setup that made it much easier to keep the engine under boost most of the time - the rest was mostly idle and that circuit is seperate so much easier to tune.

 

2. In a draw-through setup you pull air through the carb. This is easier in that the carb works as normal because it's not exposed to the pressure. This would seem to solve the problem except for the new one's you create:

 

a. The intake runner's have to be quite long to go from the carb, to the turbo, and back to the engine. This has all sorts of bad implications for tuning. The carb lags a bit behind the engine demand.

 

b. You now have highly explosive air-fuel mixture INSIDE your turbocharger, and intercooler :eek:. One good backfire through the intake durring tuning and you'll blow the intercooler up like a bomb. This is what makes the draw-through setups dangerous and for all their problems the blow-through aren't nearly as likely to put you in the hospital or burn the car down.

 

GD

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Lots of guys are running blow through setups on sandrails without any problems... I'd suggest running a google search to find out about blow through and see if that will work for you.

Otherwise, if you're mad keen on sticking a turbo on your vehicle then lets find you an MPFI intake manifold over here in the US where they're more common and ship it over to Israel...

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Im not so sure your stock build motor is going to appriciate a turbo.

Its doable but why? Too much money work and time. It would be cheaper to buy the whole deal off ebay than trying to build it from scratch and ship 20 things from 10 suppliers. I see ea82t's on ebay often.

Better yet do a weber & exhaust. Is this for competition or hobbie? If your just a shade tree hobby-wrench avoid these kinds of projects.

Ive seen turbo sandcars that are carbed. But unless they are built right they have a short lifespan. And it seems as though they are very high maintinance.

Those pics make it look soo simple though I wanna try it.

-Sam

Edited by ihscout54
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let's assume that I get an EA82 injected , with turbo.

 

the engine code is still EA82? or is it EA82T?

 

the transsmition can deal with that engine power?

 

DO I need special CV joint? and make some big changes?

 

Or I better exchange it to an EA82 MPFI .

 

lets face it , the 1800 carb is not powerfull, especially after 22 years...:-\

 

:(

Edited by erez
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why would you want to turbo a ea82 carb?

 

buy a EA82T ffs. save yourself a lot of time and pain.

 

First problem you are going to have with a turbo on a carb is detonation. Good luck running 6 psi on a 9:1 comp block

 

Keep it carb'd, but a weber on it or megasquirt FI

 

to be honest even the EA82T engines were not made for horsepower. its been tried here many times and they might run like a raped ape right off, but you are going to have a Very VERY short lifespan on your engine.

 

If you are really stuck on a turbo get a EJ22T. Proven turbo engine.

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  • 2 weeks later...

unfortunatlly in my country, this swap to an EJ engine,

it is forbidden:(

I won't pass the test and I need to do the test every 6 moths insted of 12 months:(

 

 

well thants and good luck:)

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