Drew's TBI Q&A/install thread

[TUDrewser]

Question: If I plug everything in and give it power on the bench but DON'T connect a distributor, will everything still register? I just don't have an extra dizzy laying around.

yes

But if you want the really, really cool factor, hook the dizzy and fuel pump up. Make it so the injectors will spray fuel when you turn the dizzy.

I agree that's way cool. But probably not worth the price of an extra dizzy (unless I make it to a junk yard before I bench test...)

[AwesomeJ10]

u should get another dizzy for a couple of reasons:

1 - for a spare

2 - if you mess up the dizzy when welding it (you have to weld the advance stuff together so it can't move).

[TUDrewser]

What cars other than FSJ's can I get a dizzy out of that will work (assuming I swap gears)? I just figured I'd go buy a reman'd dizzy if I messed up the welding.

[chevelleguy]

A stock reman distributor is only $50 at the parts store.

[TUDrewser]

That's what I was counting on... But still wanted to avoid the cost until I need it.

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[chevelleguy]

You will be hard pressed to find one in a junk yard in anything but a Jeep. The AMC cars only had them in the 304/360 models in '78/'79, from there I think the Jeeps were the only V8s produced until the Wag died in '91.

[TUDrewser]

Ok, think the last thing I need is fuel line. What are you guys running? Rubber hose, metal line, combination? If combination, where do you do the switch? Am I ok just running straight rubber FI line?

Also, any chance someone has the thread pitch and size of the TB fuel ports? Mine are empty female ports, so need something for that.

[babywag]

You can use many different options.
TBI - metric o-ring adapter (stock)
TBI - AN adapters (spendy)
TBI - flare adapter (I don't like this option rubber hose right off the TBI)

I use stock hard lines, then FI rubber hose w/ FI clamps NOT the normal hose clamps that chew up hose.
TBI is LOW pressure so even normal fuel line is adequate @ those pressures, but the low pressure FI hose is cheap.

Dorman PN#'s
http://fsjnetwork.com/forum/viewtopic.p ... =20#p55670

If you want pics., lemme know I can go take a few.

[TUDrewser]

Pics would be awesome if you are willing. Thanks!

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[FSJ Guy]

Yup. You don't need the high pressure fuel injection hose for this era TBI.

If you can, use as much hard line as you can. A double flare tool is inexpensive. I prefer to have as little rubber hose as possible, but I know if practicality, it is not always possible. (Geez, did that make any sense? LOL!)

[TUDrewser]

Ok, so the 800-153 will be my supply (3/8") and the 800-151 will be my return (5/16"). These go directly into the TB and come out. I'll bend them down to go down (as they are 18") and connect rubber 3/8 and 5/16 fuel line to each, OR do a fitting and keep it metal line to the pump. In fact, I think I can use my original supply line for the return, and just connect it up, right?Supply (rubber or metal) line then goes to the pump, which then has rubber to the tank fitting from the old supply. Well, filter in between pump and tank, but still rubber. Or, I just use a little bit of rubber line in between the pump and the metal lines.

Did I get this right? I'm confusing myself. How do you guys secure the metal line when routing it? Seems like rubber from pump to dorman lines would be easier to route...any reason not to other than longevity?

[TUDrewser]

Also, would I double flare the end to connect rubber hose with a clamp? What's the proper way to connect rubber fuel hose to metal tubing?

[FSJ Guy]

You don't NEED to double flare the lines, but I usually do because it results in a smoother flare. You'll want some rubber lines between the TBI and the frame to allow for engine movement.

I have also used rubber lines between the fuel pump and the hard lines. Factory installs don't always do that, but they are engineered for a perfect fit. : D

You can use "hold downs" to secure the metal lines. They are similar to the clamps that hold your A/C lines to the fender in the engine compartment.

[tgreese]

If you want to have hard line all the way to the body/frame transition, you could cut the original hard lines conveniently and connect them to more hard line with compression fittings. These are not good for brake lines, but will be fine for relatively low pressure lines like this.

Getting rid of rubber fuel lines on top of your engine seems worthwhile. Those little hoses connecting the fuel filter are a prime source of engine fires.

[TUDrewser]

Cool, thanks all. And are these the kinds of clamps y'all use: http://www.amazon.com/AAS-Fuel-Injectio ... 0040CU0HM/

I think I'll use the full 18" on the Dorman ones and then go rubber to the fuel pump and rubber to the tank. Anyone have the stock supply and return line sizes for a 90 GW? IIRC, it's 5/8 and 1/4.

[AwesomeJ10]

All my junk is running 3/8" fuel line from the tank to the TBI, then 5/16" from the TBI back to the tank. I use the part store fuel line that says 'not for fuel injection' along the side. This type of hose is commonly used for carbs, but our TBI is only running at 10-15psi; not nearly as much PSI as a more modern fuel injection system.

With regards to the lines being near the engine. On my Honcho I have the lines coming straight out the rear center of the engine compartment, going along side the passenger side frame rail, then over to the fuel cell. My single exhaust pipe is on the driver side.

With regards to fittings. Hardware stores and some parts stores carry brass hose barb fittings. If you look, you can find one that fits the back of the TBI itself. Or you can simply cut down the existing hard lines from the rear of the TBI and simply sleeve the fuel line over the hard line and secure it using 2 hose clamps on each end. I've done both and they both work.

oh and don't forget to buy a cheapie fuel pressure gauge. Very well worth it when you initially setup the TBI and for troubleshooting down the road.

[babywag]

Cool, thanks all. And are these the kinds of clamps y'all use: http://www.amazon.com/AAS-Fuel-Injectio ... 0040CU0HM/

I think I'll use the full 18" on the Dorman ones and then go rubber to the fuel pump and rubber to the tank. Anyone have the stock supply and return line sizes for a 90 GW? IIRC, it's 5/8 and 1/4.

Stock lines on a GW are 5/16" and 1/4". You do not need to change the fuel hard line sizes. A stocker runs just fine even with the small lines.

Here is pic of my '90 w/ the dorman lines, I did the same on my '88 except used junkyard chunks of hard line (PITA to rebend).





I bent them to route directly above/behind top of the power brake booster, from there it's soft hose down to the fuel pump & stock hard lines.

[TUDrewser]

babywag, so you ran 3/8" soft line to the fuel pump, right? And for the return, you connected 5/8" soft line...to what? The original 1/4" hard line for return?

[babywag]

babywag, so you ran 3/8" soft line to the fuel pump, right? And for the return, you connected 5/8" soft line...to what? The original 1/4" hard line for return?

TBI > dorman 3/8" hard line > 3/8" hose > fuel pump 3/8" hose > fuel filter < 5/16" hose < 5/16" hard line < tank.
TBI > dorman 5/16" hard line > 1/4" hose > stock 1/4" return hard line.

EDIT: My fuel filter is for a '95 Ford Thunderbird (w/ 4.6 v8)it has 3/8" out and 5/16" in.

Fuel pump & filter are mounted on driver's side frame rail in front of fuel tank, hard lines cut there.

[TUDrewser]

That's hugely helpful. Thank you.