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Fuel Injection vs Weber

weber carb fuel injection mpg

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22 replies to this topic

#1 wagondragon

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Posted 10 April 2014 - 02:12 PM

So i have a 85 station wagon, its currently got a weber on it. running great. But i recently bought a 87 FI manual trans wagon for 350$... It even runs! besides some serious fuel flow issues i drove it home 15 miles. My question is if i get the FI system working well, which would be better for mpg, FI or a weber? i plan on transplanting the 5 speed trans in either way.



#2 bratman2

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Posted 10 April 2014 - 04:59 PM

Pretty sure the fuel injection would by a small margin, maybe 1-mpg! Should gain a few horses too, maybe 3 or so over a good tuned Weber.



#3 chompy

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Posted 10 April 2014 - 07:03 PM

Webers are fun to play with... 

 

 

$.02



#4 wagondragon

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Posted 14 April 2014 - 06:16 PM

Really, for some reason i thought it would be more drastic. So it wouldn't really be worth swapping one over from a 87 to my 85.



#5 1982gl4

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Posted 14 April 2014 - 07:13 PM

On my 1984 fwd wagon I had a weber, and swapped to spfi. I went from 29mpg around town to 31, but I haven't yet driven it on the highway to see what my gains are there. Power seems to be very similar between the two, a bit smoother with the FI. I will say it sounded way better with the weber!



#6 ferox

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Posted 14 April 2014 - 07:14 PM

It depends on what kind of gas mileage you are getting with the Weber.  If it is tuned correctly then the difference may be slight.  Many if not most Webers that run great are not actually tuned in.  If you are not getting high 20s for mpgs, then it's not a proper comparison.  FI will just be better.  It's kind of like comparing a computer to an adding machine.  FI will also be superior if you are at elevation...say 3000 ft or greater.

 

So the real question is, again, what kind of mileage are you getting with the Weber?  Or, if you are not getting 27-29 mpg with the Weber, then FI will give you better efficiency at every elevation.



#7 josolong

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Posted 15 April 2014 - 12:02 AM

man i'd love to get 29 city with my weber..



#8 rrgrr

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Posted 15 April 2014 - 09:16 PM

I am getting 28+ with mine without trying and 26" tires :D



#9 bratman2

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Posted 15 April 2014 - 11:09 PM

The original EPA rating was 24 city and 26 highway if my memory is correct. I live in the deep sticks, have to drive pretty far to find a stop light. Keep my Brat tuned and know what the speedometer error is. I consistently average around 29.5 mpg running 60 or less. I think that is pretty outstanding for a carbureted, no computerized vehicle that turns 2700 rpm at 55 mph. I have gotten as high as 31 mpg but that was driving super careful for maximum mpg. Wind and load will make a decent dent in the mpg. Short of dropping a fuel injected EJ18 in I don't see much room for improvement in mine.    



#10 josolong

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Posted 17 April 2014 - 02:21 AM

dam nice all around!

 

i've never checked how my weber is jetted but always mean to.. it was bought used and installed by the previous owner. i get abt 16 city mpg (up and down hills in seattle) and 24-25 highway. it's tuned in about as good as i can get it without diggin into those jets, and notwithstanding some other (vaccuum) issue entirely.

 

the best measure i ever got was 26 hiway driving 75mph in the rain with a couple of big guys for passengers. still dont quite get that one.



#11 bratman2

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Posted 17 April 2014 - 07:21 AM

Tail wind, lol!!! That isn't too bad. Isn't Seattle a decent amount above sea level? Mine is a Redline kit I installed maybe 14-15 years ago. I did go through the "best lean idle" tune instructions 5 times are so, lol! I did notice a decent improvement in low and mid range power. I also have for the last 4 years or so been running 87 non-alcohol gas. I have not checked the mileage lately but need to just out of curiosity.



#12 Gloyale

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Posted 17 April 2014 - 10:39 AM

Tail wind, lol!!! That isn't too bad. Isn't Seattle a decent amount above sea level?

 

.......it's pretty much at sea level.  You know with being one of the largest ports on the Pacific and all.

 

Steep hills like San Francisco though.



#13 bratman2

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Posted 17 April 2014 - 02:35 PM

Oops, you got me. For some reason I was thinking mountains. My mother lived in Washington State in the 50's and talked of the mountains.



#14 Gloyale

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Posted 17 April 2014 - 07:05 PM

Well there are lots of mountains in Washington.

 

Just not IN Seattle.



#15 TallonX

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Posted 17 April 2014 - 07:10 PM

With how the grade is on some of them roads... Might as well call it a mountain XD

#16 wagondragon

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Posted 04 July 2014 - 11:19 AM

I want to say i get about 20-22 mpg, maybe alittle more just on the highway. I do allot of mixed driving so its hard to say just city driving.



#17 Loyale 2.7 Turbo

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Posted 04 July 2014 - 12:16 PM

... Power seems to be very similar between the two, a bit smoother with the FI. I will say it sounded way better with the weber!

 

Yes, I Agree...

 

The Weber at Full Acceleration provides an Awesome Sound to the Car, the Fuel injection quiets the Engine and power is Similar if not equal with a well tuned Weberized engine; I only suggest to go to Fuel injection if the car moves from nearby the sea level to Higher altitutes constantly or frequently, otherwise, in my own humble opinion, I prefer the Weber, not only for the Boxer Rumble, but also for its Simplicity.

 

Kind Regards.



#18 jono

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Posted 04 July 2014 - 05:46 PM

So....3 months nearly have passed - anything happened here ? Fuel injection gone in ? EFI has the added advantage of injector cut on throttle off and above about 1500rpm, so more often you can back right off on loud pedal, save fuel squirting in



#19 wagondragon

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Posted 04 July 2014 - 06:37 PM

I was super busy with school... just recently started working on it again... its kinda my donor car since i decided to stick with the weber instead of bothering to convert the FI... Currently im trying to fix the FI in the 87 that its in. ( my main car is an 85 wagon weberized ) As you might have seen in my other post i cant get it started, the FI just isn't getting volts. But getting back to the subject at hand. I decided to keep both as they were... for simplicities sake. 



#20 Loyale 2.7 Turbo

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Posted 05 July 2014 - 03:01 AM

Good Idea!

 

By the way, my Weberized "BumbleBeast" also is an '85 Wagon.

 

Kind Regards.



#21 el_freddo

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Posted 06 July 2014 - 07:22 AM

Hmmm... I need to get me one of these SPFI kits to play with some day...

Personally I'm an EFI convert after stuffing around with an MPFI conversion to my originally carbed L.  I'm currently considering MPFI'ing an EA81 more for shits and giggles than all out fuel economy...

 

Cheers

Bennie



#22 Dinky26

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Posted 06 July 2014 - 12:15 PM

I want to say i get about 20-22 mpg, maybe alittle more just on the highway. I do allot of mixed driving so its hard to say just city driving.


This is the same as I am getting on my 86' Brat Weberized.

Just replaced the cap and rotor the other day, so I'm hoping that will help my MPGs. I will say it runs better now at least.

#23 wagondragon

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Posted 06 July 2014 - 02:25 PM

Forgot to mention its AT, hoping to swap a 5 speed in there from the donor car i recently bought. That should increase my milage significantly :D







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