when doing the 1.6 8v conversion on a samurai i realize that the sole purpose is not only for power but fuel injection, but are alot of people saving the time and money and just running the carbed set up? if so is there a power loss, mileage loss, performance loss of any kind? i have had nothing but trouble with my samurai getting too much fuel with my efi and it smokes badly so im wondering if i should have just stuck with my weber setup off the 1.3 and bolted the manifold to the 1.6???

when doing the 1.6 8v conversion on a samurai i realize that the sole purpose is not only for power but fuel injection, but are alot of people saving the time and money and just running the carbed set up? if so is there a power loss, mileage loss, performance loss of any kind? i have had nothing but trouble with my samurai getting too much fuel with my efi and it smokes badly so im wondering if i should have just stuck with my weber setup off the 1.3 and bolted the manifold to the 1.6???

Couple things come to mind. If you've purchased one of those hi pressure fuel pumps (like 60-90 psi ish) that are real noisy, you know the one, and don't have an adequate return line you could be overwhelming your 8-valve fuel regulator. Maybe try something more appropriate for a TBI system (20-30 psi-ish).... or make a bigger return line. Troublshoot by making a large return line that you can have dump back into the fuel filler inlet for a quickie, let's see if that's it, type test...

....and 1.3 carb'd systems, either stock or Weber will bolt right onto the 8-valve engine and will work just as good as they did for you on the 1.3. You still get the HP and torque gain of going to the 1.6.

Good luck, Eric

i appreciate it, im gonna try that return line trick, a few people have mentioned that already. what is the benefit of having that higher pressure pump as opposed to the the lower one you mentioned (or is there even a benefit at all)? and yes, i do have that darn noisy pump! its really annoying

If you switch from the Throttle Body injection to a Multi-Port Injection you will need the higher PSI.  Other then that, not much.

Maybe try something more appropriate for a TBI system (20-30 psi-ish).... or make a bigger return line.

TBI requires 43.5psi at the injector. You really need to look at the pump rating in terms of both psi and gallons per hour. A pump thats rated at say 60gph |removethispart|@ 43.5psi will need a lot more fuel returned than one rated at 40gph if you are only using 20gph. PSI is just a function of the flow rate and the size of the injector/demand, if the demand is greater than the pump capacity then the pressure will fall. You should chose a pump based on a calculation of gph |removethispart|@ 43.5 psi based on your estimate of worst case fuel consumption and maximum speed. Get one thats rated at more than you need so you never run lean but stay away from the type of pump sold for tuned Subarus and the like.

FWIW: The TBI system calls for 34psi to 40psi of pump pressure any more than that is recirculated.

-Eric

FWIW: The TBI system calls for 34psi to 40psi of pump pressure any more than that is recirculated.

-Eric

My mistake, I thought from memory that it was a standard 3 bar regulator. The stock fuel pump is rated at 21.1 gph |removethispart|@36psi

OK so what fuel pump should be used for this application?

Anyone identified a suitable external fuel pump with about 40PS of pressure?  Maybe something from another vehicle that is an external pump?

How about a high pressure pump with a high pressure regulator?

Thanks
Hutch