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Carb to FI..I know this has been asked many times before but...


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for installing a SPFI system from an 90 loyale to an 85 carb loyale...is there anything that one needs to know to avoid any unforseen problems that may have not been mentioned on this site, or even wrongly assumed ideas ...I have the complete FI car so I am thinking all should go well

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I'm curious about this as well.Just got a rust free carb'd wagon-1987.

 

I think it's a question of fuel presssure.If I recall rightly,the tank is more pressurized?Or the pump runs at a higher preessure?

 

That being the case,the next Q would be,Can I just swap in an SPFI pump and then proceed to swap the intake system?

 

I've got the perfect donor car for the repairs needed and conversion if possible.

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I don't know whether the manual covers this or not, but MAKE SURE YOUR ECU (computer) CASE IS GROUNDED or else you will fry it. It took me 3 months (weekends only) to figure out the problem, other than that, it is pretty strait forward.

I think it's a question of fuel presssure.If I recall rightly,the tank is more pressurized?Or the pump runs at a higher preessure?

 

That being the case,the next Q would be,Can I just swap in an SPFI pump and then proceed to swap the intake system?

 

I've got the perfect donor car for the repairs needed and conversion if possible.

The SPFI pump runs at a higher pressure, you will need to swap the pump and intake at the same time (I still need the right pump, mine is running on BMW pump and I am having issues).

 

The SPFI pump's pressure is far too high for a carb to handle.

 

It would also be a good idea to replace all your rubber fuel lines, as they are pretty old, and designed for 4 psi, not 40+ psi. Make sure that you get ones that can take 50 or more psi.

Conversion is very doable with a good parts car, I had a junkyard full of wrecked/worn out junk to work with, which made it very difficult for me to get good parts. (and whatever I got was in question) Anyway, a running parts car is the way to go.

 

I like to see 85's and 86's on the road because they are very individual.

Both had a different control layout from later models, and the 85's do not have the center stoplight (my parents had the dealership add it on when the 86's came out).

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IIRC, there was also an issue regarding the fuel return line... either the carb didn't have one or it was inadequate for the flow/pressure of the EFI systems.

 

I'm not positive about the earlier models, but all carbed EA82s have fuel return lines. I used the stock one and haven't had any problems yet.

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I'm not positive about the earlier models, but all carbed EA82s have fuel return lines. I used the stock one and haven't had any problems yet.

I was wondering how you routed that. Yes stock ones work ... if you don't try to bleed off excessive pressure through them!

I think all Hitachi EA81s (or at least 83 and 84 ones) also have the fuel return line. It is smaller than the SPFI cars, but so is mine!

 

If you are really concerned, you can switch stuff around because the line to the tank for the EVAP canister is the same size as the fuel line on FI cars.

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