build thread for 2.8 carb to chevy tbi.

[cammeddrz]

i never thought of the air-filter clearance. rico seems to have a mile of room, but also your adapter plate looks much thicker too.

 

[Lil-Pony]

well the old phenical spacer was about 1/2" an and the aluminum piece yall made was about 1/2" so overall it was 1" same as the one i had machined.

 

[cammeddrz]

our adaptor plate was only 5/16", and as I recall the phenolic was closer to 7/16"

which puts us 1/4" thinner than you

I picked the thickness of plate so that the OEM 2.8L throttle cable would line up as close as I could while still using the ford bracket

 

[Lil-Pony]

Well hopefully that 1/4" isnt to much. My carbs spacer was alittle over 1/2" so i assumed the aluminum was close to the same measurement.

Can any one tell me what each vacuum port for the tbi goes to.

 

[cammeddrz]

they are all the same vacuum, meaning that they all go to manifold vacuum. use as many as you need to hook the ford vacuum stuff up to. and cap-off the rest.

 

[Lil-Pony]

ok so the pcv valve goes to main vac and the vapor canister as well, doesn't the canister get a vacuum resistor inline with it?

 

[dangerranger83]

I ran a regulator on mine but it was a returnless one. It helped but still wasn't enough. If I had the time when I was doing it, I would run a return regulator and plug the return line off at the 3.8 tbi.

I also didn't run any of the emissions stuff either. My setup came from an automatic so I had to disable the idle actuator or I would have a hanging high idle (2000rpm) that would last any where from 2-12 seconds before going back down to idle speed.

Did this swap on my dad's old ranger that too had a 2.8, manual, and from start to finish, did the tbi swap in ten hours (putting in a new fuel tank with a pump inside, running lines, etc...) and she was back on the road. But his too ran rich and couldn't get it as tuned in as we wanted (but man it had some nuts when you got on it and looked like a diesel too) so he too went the duraspark way.

Sent from my rooted SPH-D710 using Tapatalk 2

 

[Lil-Pony]

well now she wont fire, she sputters and and backfires from the tbi, my fuel filter appears to be empty no matter how long i crank. i think the mechanical fuel pump cant keep up with the electrical pressure pump, how can i test the pressure regulator, and can i eleminate the mechanical fuel pump with a inline rail pump near the fuel tank? what psi would this pump need to be, what car/trucks can i pull this pump from.

 

[cammeddrz]

you are looking in the wrong direction

the mechanical is a diaphragm pump and pumps at near maximum volume at idle

the mechanical will move more volume of fuel than the electric will at the tbi pressures.

meaning at 12psi, there is no way the electric could out-pace the mechanical.

using the mechanical to feed the electric works just fine

you have another problem

the only option that would work better than this one would be a gravity-fed pump (like an in-tank pump), which isn't an option on an '84 because you truck has the tiny opening on the tank, which won't allow for the use of an in-tank.

if you eliminate the mechanical, which is a diaphragm and therefore has the ability to "pull" fuel. in favor of an inline (that can't "pull" fuel) you would invite more problems because of that

 

[Lil-Pony]

ok so that still doesnt solve the no fuel in my filter issue, could my mechanical pump be weak?
btw my fuel lines go tank / filter / mecahnical pump / high pressure pump / tbi

 

[cammeddrz]

ok so that still doesnt solve the no fuel in my filter issue, could my mechanical pump be weak?
btw my fuel lines go tank / filter / mecahnical pump / high pressure pump / tbi

mechanical pumps are vulnerable to vapor-lock. or your pump could also be weak

I don't recall there being a filter before the mechanical pump did you add that in?

 

[Lil-Pony]

Yup it one of those cheap spectra filters so i can see if there is fuel in the line

 

[cammeddrz]

there is a reason ford put the filter after the mechanical pump. I am thinking that the addition of that filter might have something to do with it.

pull it out, and see what happens.

 

[Lil-Pony]

K. Will try that and see what happens

 

[alwaysFlOoReD]

the only option that would work better than this one would be a gravity-fed pump (like an in-tank pump), which isn't an option on an '84 because you truck has the tiny opening on the tank, which won't allow for the use of an in-tank.

if you eliminate the mechanical, which is a diaphragm and therefore has the ability to "pull" fuel. in favor of an inline (that can't "pull" fuel) you would invite more problems because of that

I'm not familiar with the different years of b-II tanks. I bought an 84 or 85 with a 4.0l installed. Apparently he used a mustang pump in the stock b-II tank. I had it out while tracking down a fuel problem. He filed a bit on the hole to make the alignment protrusions of the in-tank pump housing to line up. The problem I found is he used non fuel rated line to attach the pump to the housing and it had cracked causing low pressure.
I don't know if this pic shows anything worth noting but....;



On my race truck I have a cell, and I use an aftermarket low pressure inline pump mounted on top. There are two filters between the tank and the low pressure pump. In the pic it is near the top and looks the same as the second fuel filter.



It feeds through a fuel accumulator and then into a high pressure frame mounted pump from a 88 f-150. I believe the ranger used a similar frame mounted high pressure pump from 86 to 88/9

I don't know if either of these would be a solution but there's some ideas.
Good luck,

Richard