86 f-250

stegomon · 09-22-2008, 08:46 PM

got an 86 f-250 efi 302...no balls..no power..yada yada yada....know how to fix it.....swap in a 4bbl!!!!good bye efi...haha...any who...i dont know what the tranny is....i think it is the aod...if so....can i make that tranny work with a carb set up?

**Will** · 09-23-2008, 02:54 AM

No balls because it needs a 460. It won't make more power by adding a 4bbl. Look down the throat of a 4bbl. You have 4 little 1" venturis in there, with booster venturis and other assorted junk in the way, then a 90* turn at the bottom and runners going everywhichway. So 4 1" venturi's is 506mm^2 and one 60mm TB is 2,800mm^2 in area. It would take a really big carb to flow with an EFI--and that large of a carb wouldn't have enough airspeed through the venturis to pull the fuel out of the bowls at low speeds. And the EFI has no 90* bend for the air to slam into. The carb needs disturbances (like venturis which choke the airflow to make the air speed up for the pressure drop to pull the fuel up through the jets) built into the system to keep the fuel particles from seperating out. The EFI flows more air, period. Why do you want to choke your engine? That's not very much engine for an F250. Like I said, the real answer is get a 460. Even a 5.8 is kind of weak in an F250.

And the computer is probably doing the 3-4 shift and the converter clutch lock-up.

85_Ranger4x4 · 09-23-2008, 09:52 AM

What kind of EFI is it? If it is throttlebody then there are probably better ways to get the fuel to the engine.

I doubt a 1986 has a computer controling much of the transmission.

Also remember that this thing is 22 years old, how good of shape is the engine in? A 3/4 ton is a lot of truck for a healthy 302 anyway...

Shran · 09-23-2008, 06:23 PM

An 86 would be multiport I believe. In any case, not TBI. Should look similar to this:

I'd second the 460. The 302 in my F150 feels like it has a ton of power, but no torque. Pulling trailers and stuff just kills it.

86bigred · 01-03-2010, 06:50 PM

I would go with a 351,easy swap.the 460 you would need a trans as well.the 300-302-351 w all use the same trans.my 81 has a 302,no power till the rev get high.my 86 has a 460,will pass any thing but a gas station.my 85 has the 300 I6,great low end torque but doesn't rev.so it depends on what you want to do with the truck?
You should have the aod trans with efi.if you switch to a carb you will need a standalone computer for the trans(early non electronic diesel trucks have this computer), plus with a carb swap you will have to do a duraspark II conversion as well.
The simplest thing to do is drop it a 351 w efi engine.
There is also the option of a vortec or Paxton supercharger.

gaush007 · 07-10-2010, 05:07 AM

Can I get pics and the price of the vehicle.

09-22-2008, 08:46 PM	#1
stegomon New Member Join Date: Aug 2007 Location: auburn/minot maine Year: 1987/1990 Make: fords and only Model: ranger Posts: 3 Rep Power: 0 iTrader: (0)	86 f-250 got an 86 f-250 efi 302...no balls..no power..yada yada yada....know how to fix it.....swap in a 4bbl!!!!good bye efi...haha...any who...i dont know what the tranny is....i think it is the aod...if so....can i make that tranny work with a carb set up? __________________ 1987 ranger super beast__1990 ranger duff lift_________________2.9 to 4.0 swap dana 35 and sploder 8.8___duff 3 inch lift 302 swap_______________locked front and back cab off frame 97 ranger DD 3.0 manual every thing after market headlights 4.0 S.O.H.C swap in the works

09-23-2008, 02:54 AM	#2
Will Super Moderator Join Date: Nov 2001 Location: Brown County, Indiana Year: 1989 Make: Ford Model: Bronco II Engine: 4.0 Class: 4X4 Used For: Collecting rainwater Posts: 168 Rep Power: 10 iTrader: (1)	No balls because it needs a 460. It won't make more power by adding a 4bbl. Look down the throat of a 4bbl. You have 4 little 1" venturis in there, with booster venturis and other assorted junk in the way, then a 90* turn at the bottom and runners going everywhichway. So 4 1" venturi's is 506mm^2 and one 60mm TB is 2,800mm^2 in area. It would take a really big carb to flow with an EFI--and that large of a carb wouldn't have enough airspeed through the venturis to pull the fuel out of the bowls at low speeds. And the EFI has no 90* bend for the air to slam into. The carb needs disturbances (like venturis which choke the airflow to make the air speed up for the pressure drop to pull the fuel up through the jets) built into the system to keep the fuel particles from seperating out. The EFI flows more air, period. Why do you want to choke your engine? That's not very much engine for an F250. Like I said, the real answer is get a 460. Even a 5.8 is kind of weak in an F250. And the computer is probably doing the 3-4 shift and the converter clutch lock-up. __________________ -'89 B2--4.0, 5spd, D35, 8.8, 4.10, pair of Lock-Rights, Superwinch Epi 9.0, James Duff with Jeep XJ coils -'87 Honda Civic Wagovan--76hp, 37mpg town -'88 Chevy crewcab--6.2L Banks turbodiesel, TH400, Gear Vendors splitter, 14-bolt w/4.10s & No-Spin -'91 IH 3800 "Skoolie" RV--DTA360, Fuller 6-speed My Website Last edited by Will; 09-23-2008 at 03:05 AM.

09-23-2008, 09:52 AM	#3
85_Ranger4x4 Junior Member Join Date: Aug 2007 Location: Between Omaha & Des Moines Year: 1985ish Make: Ford Model: Ranger Engine: 2.8 Class: 4x4 Used For: A Project Posts: 82 Rep Power: 7 iTrader: (0)	What kind of EFI is it? If it is throttlebody then there are probably better ways to get the fuel to the engine. I doubt a 1986 has a computer controling much of the transmission. Also remember that this thing is 22 years old, how good of shape is the engine in? A 3/4 ton is a lot of truck for a healthy 302 anyway... __________________ 1985 Ford Ranger Custom, Durasparked 2.8 OHV V-6 4x4 W/ a PA 3" BL. The fact that it still runs defies almost every law of the internal combustion engine. 2002 F-150 XLT, 5.4 SOHC V-8 4x4, 3" GOTT's intake, 2.25" true duals with Thrush Glasspacks.

09-23-2008, 06:23 PM	#4
Shran New Member Join Date: Mar 2008 Location: Rapid City SD Year: 84/85/86/87 Make: Ford Model: Rangers/Bronco II Engine: 2.9 Class: Unicycle Used For: Hauling crap from the dump to the dump Posts: 21 Rep Power: 0 iTrader: (1)	An 86 would be multiport I believe. In any case, not TBI. Should look similar to this: I'd second the 460. The 302 in my F150 feels like it has a ton of power, but no torque. Pulling trailers and stuff just kills it. __________________ 1986 Ranger XL 4x4, 302, NP435/205, EB D44, 8.8 open/ls, 35" BFG M/T *in progress* 1987 Bronco II 4x4, 2.9, A4LD, 1350M, 4.10 D28/7.5 open/open, 33" Wildcat EXTs, 6" SkyJacker lift 1984 Ranger XL 4x4, 2.8, TK-5, 3.73 D28/7.5, stock height, 33's 1985 Ranger XL 4x4 will be scrapped

01-03-2010, 06:50 PM	#5
86bigred New Member Join Date: Apr 2009 Location: patricia Alberta Canada Year: 81,85,86 Make: ford Model: F150,250 2wd&4x4 Engine: 300,302,460 Class: 2wd Used For: 81 dd 86 work horse,85 toy Posts: 7 Rep Power: 0 iTrader: (0)	I would go with a 351,easy swap.the 460 you would need a trans as well.the 300-302-351 w all use the same trans.my 81 has a 302,no power till the rev get high.my 86 has a 460,will pass any thing but a gas station.my 85 has the 300 I6,great low end torque but doesn't rev.so it depends on what you want to do with the truck? You should have the aod trans with efi.if you switch to a carb you will need a standalone computer for the trans(early non electronic diesel trucks have this computer), plus with a carb swap you will have to do a duraspark II conversion as well. The simplest thing to do is drop it a 351 w efi engine. There is also the option of a vortec or Paxton supercharger. __________________ 86 f250 460 4x4 4sp t18 81 f150 302 4 sp od 85 f150 300 4sp t19

07-10-2010, 05:07 AM	#6
gaush007 Banned Join Date: Jul 2010 Year: 2005 Make: Ford Model: SD Posts: 10 Rep Power: 0 iTrader: (0)	Can I get pics and the price of the vehicle.

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