Is Fuel Injection worth the $$$

[JW]

I'm considering spending $800+ to convert my 90 Grand Wagoneer to TBI. I have the Edelbrock carb & manifold now. For thoses of you who have made the leap into the 20th century and installed fuel injection, is it worth money? What were the most noticable changes? I need to sell this plan to my wife:)
Thanks

[Cecil14]

I don't think I would be able to justify $800 for FI. Most people from what I've heard only get about 3-4 mpg better at most. It would take a very LONG time to recoup that in fuel savings. If you can properly tune your carb and keep a light foot you should be able to keep your fuel economy fairly good.

If you are going to get FI try ebay, I know a lot of guys on here say that you can get used parts fairly cheaply on there instead of buying expensive new ones.

Just a thought,
Anthony

[243]

Fuel injection is probably the most significant improvement to the internal combustion engine in our lifetime. FI provides lower emissions, longer engine life, better efficiency improving fuel mileage; and, driveability is superior to any carb equipped vehicle. Those are all great benefits for us flatlanders. No fuel slosh for the offroaders, no vapor lock for those in the desert or congested freeway's in the middle of summer.

If I won the lottery, I would buy everyone on IFSJ one of TPIGuy's TBI kits :cool:

[ May 18, 2003, 10:06 AM: Message edited by: 243 ]

[netbear]

I've driven both off-road. Fuel Injection is
the only way to go. The engine runs smoother,
does not flood at steep angles and runs great
at any altitude. Fuel economy will improve as
well. My opinion anyway...

[Chero77]

There is no doubt that fuel injection is better than a carb. However, there are two broad categories of fuel injection TBI (throttle body) and MPI (port fuel injection). MPI is way better than a carb. TBI is a little bit better. Is TBI $800 better? Only your wallet can say. I guess if your running a fresh rebuild and everything else on your rig is in tip top shape sure, then yeah maybe. But if its a 100k motor, then use the cash for a rebuild. TBI won't solve any problems related to a tired engine.

[Mikel]

Remember we have 5000 members :D

Originally posted by 243:
If I won the lottery, I would buy everyone on IFSJ one of TPIGuy's TBI kits :cool:

[Mike D]

Is TPIGuy settled in yet??

Heard he was moving...., bu tthat was a while ago.

[RWC]

I'd say that TBI is way better than a carb, and MPI is a little better than TBI. Even TBI, in closed-loop, gives you all of the previously mentioned improvements. You also need to consider that there are multiple forms of MPI too, if you start down that path.

RWC

[KYJ10]

I just finished putting a TPI kit on mine, and it ran like my new car, to bad the rebuild went south. But if you off road alot, it is a great investment. I built mine just for off road, and got sick of stalling out on steep angles. Granted, they were pretty extreme, but thats what I built it for. And I hate not being able to climb something that you shouldnt' be able to in the first place! Fuel injection solved that.

[medicineman]

how was TPIGuy's little project coming along anyways?

[Serious Johnson]

I'd agree with but modify what RWC said to read:
Throttle Body Injection is a LOT better than a carb, and Multi Port is a little bit better yet for efficiency, and a good bit better for power.

I don't know the topography around Susanville, but these rigs with carburetors and catalytic converters were never designed for more than about 4'000' of elevation change.

My '83 (with an "altitude-compensating" 2150 carb) is jetted to run ragged-edge lean here at 1,200' in SC, yet just barely goes at all (maybe 25 HP and <2 mpg) back home at 12,000' in Colorado.

A decent fuel injection setup with ECU control can get even our silly old V8s to operate sorta efficiently at any elevation.

If I lived in Iowa, I'd likely tune a good carb for the predictable conditions and spend the extra half-grand on something else.

:-

[LRRH]

Remember we have 5000 membersThat's only $4 MIL.....if he only buys one kit for each member. I want one for both my FSJs though!!

[Stuka]

Personally the only reason I would go with efi is if I was doing some major offroading that some some super extreme angles.

For street, a well set up ignition and carb will get close tot he same milage. I can squeaze 15mpg out of my cherokee with a performer going 65mph if i watch my foot. Which is almost the same milage our '97 K1500 4x4 chevy pickup gets with its TBI 350. (it gets 15.9)

When it comes to pure power, with no care for emmisions or milage, carbs provide more power. They get better atmization then EFI. Which is why drag racers and such still use carbs. As well as Ferrari's, they all have carbs if I recall correctly.

TBI will get better power if set up correctly then a MPI or TPI setup in most all cases if fuel milage is done away with.

So for a given gas milage rating, EFI is better. But if all you want is power, a carb will do better. Hook up a O2 sensor to a guage inside the cab, along with a fuel pressure guage, so you can monitor them if you like.

But if EFI got better power overall then carbs, carbs would have disapeared from racing a long time ago. But if you look, everything from speed bikes, drag racers, formula 1...they all use carbs.

[chrism]

I installed a custom EFIs TBI about a month ago on my 360 which had about 78K on it. All emissions except the air pump are still intact.

Compared to the stock 2bbl setup it seems to have much more power at all RPM's. Drivability has increased greatly.
Fuel consumption seems to be about the same. I was getting 14mpg highway with the 2bbl. Have not calculated it since but I'll bet its about the same. I seem to be at the gas station at about the same intervals.

The downside was that it took about 9 months to get my system from Custom EFI's. I actually gave up on it at one point and started building a MPI 351W to swap in. But it runs so well with the TBI that I think I will just run it till it dies.
So i have a 351 sitting in the garage. I guess I'll have to get a mustang to put it in.

[JW]

Thanks for all the input. With so many miles on my rig (165,000) I think I'll save my pennies for a new engine and keep my eye on e-bay for a holley system.

[243]

4,999 cuz Stuka's not interested :cool:

[Serious Johnson]

Originally posted by Stuka:
...But if EFI got better power overall then carbs, carbs would have disapeared from racing a long time ago. But if you look, everything from speed bikes, drag racers, formula 1...they all use carbs.I beg your pardon, but virtually the only race cars that still use carbs are in classes that impose a substantial penalty on fuel injection. The last F1 car with carbs ran maybe 40 years ago, and there's a reason that it lost.

Carburetors can work well in a controlled environment, but can't hold a candle to even the simplest EFI setup in the real world.

If I never planned to use my Jeep as a daily driver, or take it out of a 4,000' elevation window, then I'd likely stick with a carb for cost reasons.

:-

[ May 19, 2003, 06:05 PM: Message edited by: Serious Johnson ]