Another "Is Fuel Injection a Worthwhile Upgrade?" Question

j par said:

maybe we can find you some old bias-ply tires so you can really enjoy your nostalgic experience LOL.....
For me I would just do it to learn about it and try to perfect my skills at tuning it and working on it... Just like the entire Nitrous system that I put in and have not used yet... when I cease to learn you'll probably see a duster on Craigslist for sale...

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j par said:

I do like the idea of an infinite tunability as far as air fuel ratio and timing.. I've been browsing today for a system that is also nitrous capable... I do have all the MSD stuff and I know there's a lot of it I wouldn't need but I don't really want to lose my box or distributor if I don't have to... I imagine I would just be able to lock out the distributor and let the computer take over...

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lead69 said:

If you're thinking was correct then we would have to experience everything first hand for it to be a fact hence there would be no facts except to us lol. The answer is no but I have been around/involved more than enough of it too know. Find me one case where efi made more power than a carb in back to back tests, or better yet explain to me how any of the facts I stated are wrong other than wanting to have the convenience/drivability of a modern car. Not talking about power adders here just n/a.

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lead69 said:

Bias ply tires and state of the art trickflow heads! AND NO TIME SLIP, that's how I roll b**ch!, and don't forget it with you're ac, nitrous, 10" plenum tunnel ram and HOLLEY STREET DEMON carbs, AND GOOD LOOKS...

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AndyF said:

EFI allows me to build more power for street cars. EFI can improve consistency for race cars and it can often improve performance.

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lead69 said:

I would like to see the back to back results vs carbs. Also its important to note the type of build and budget. I am not anti efi but like anything to paint it with a broad brush and say its an upgrade period is incorrect. I recognize that there are allot of guys wanting to have the cake and eat it too but to say it is a better option depends on many things. For most like myself there is no benefit to the price/effort to convert to efi, it will not make more power and affect drivability enough for the conditions I drive it in to be worth while.

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j par said:

What wait a minute you drive your car?...
..

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lead69 said:

Yes, without ac, or fuel injection or for that matter without exhaust lately. I'm thinking you went from watching roadkill to bitchin rides from the changes you're car has underwent.

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318willrun said:

I guess for me anyways..... if I wanted MPFI, A/C, Cruise, Tilt, Power Windows, Power seats, Rack n pinion steering, Blue Tooth, 8 speed automatic, and might as well throw in a few air bags for safety.... I would just buy a newer or new Scat Pack and be done with it. They are good looking cars and do everything some are trying to do with a 50 year old car. I usually rip out the power steering for manual steering, power brakes for manual brakes, get things as open and plain as I can so under the hood can be my happy place.. But.... that's just me.

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my68barracuda said:

GoldDuster318,, when YR makes comments like that, just let it go, obviously he is troubled, perhaps off his meds,,,
I was giving him some credit earlier when I said he probably knows more about cams than I do, then he makes the comment ,,,,"Roller cams are another needless, useless expense cause by CAFE"
clearly saying that he does not understand the benefits of new technology roller cams.

YR there is a genuine need for the folks that know and keep the spirit of the older technology motors alive. Stay at it. You should continue to focus on what you are comfortable with. Carbs will never go away, there will always be a need for folks like you.
And at the same time leave the FI and roller cam analysis to folks that actually know how to run them and know the benefits they bring.

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j par said:

Personally I like to learn and I know my dual Street Demons inside and out..
Having that kind of infinite carburetor and timing to nobility on the Fly sounds very interesting and I'd like to learn more first-hand...
And yellow saying it's junk is my number one indicator that it's not...

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pishta said:

Do you run or race with a mechanical or vacuum advance? Race on the weekends get groceries on Monday?? Dyno numbers are not the end all peak of performance if 'performing' is based on the ability to get the vehicle moving in sub zero weather, have it idle at 210F with the A/C on, lug a load up a hill with a 6000 foot elevation change...and still run close to what it did at sea level. Knock sensors? The ability to pull back the timing on the fly when the sensor detects knocking or when you have to use a different grade fuel on the road. How about hop out rate on your advance. Need it all in faster, need to add more at top end? Flexibility is built it without spring or advance pot changes. Interesting that you wont change your advance curve from the street to the strip. Is one advance curve ideal for both? Buying an EFI system will adapt to a wide variety of motors, street or strip. Without setting up your curve to your specific motor (and possibly to its function that night) on a distributor machine, I think your leaving performance on the table, either in ET's or driveabilty, opposite ends of the spectrum. Here is a quote from someone obviously more educated on the matter than me, "...Vacuum advance calibrations are different between stock engines and modified engines, especially if you have a lot of cam and have relatively low manifold vacuum at idle. Most stock vacuum advance cans aren’t fully-deployed until they see about 15” Hg. Manifold vacuum, so those cans don’t work very well on a modified engine; with less than 15” Hg. at a rough idle, the stock can will “dither” in and out in response to the rapidly-changing manifold vacuum, constantly varying the amount of vacuum advance, which creates an unstable idle. Modified engines with more cam that generate less than 15” Hg. of vacuum at idle need a vacuum advance can that’s fully-deployed at least 1”, preferably 2” of vacuum less than idle vacuum level so idle advance is solid and stable.." Just pointing out the fact that different curves suit different motors and all these curves can be had i(or learned) in one system. Time marches on....

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TT5.9mag said:

Well at least you didn’t say I was wrong. Lol it’s not about the government, it’s not about emissions, for me. It’s about getting the most enjoyment I can from my old junk, and most people don’t drive their old clapped out hot rods because they are inconvenient once you get beyond their novelty. I want to enjoy them. And the two (ok 3) biggest improvements I’ve made in any old vehicle are, in order of most enjoyable, are;
1. turbos, nuff said.
2. Modern mpfi
3. Overdrive wether auto or manual

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goldduster318 said:

The coolaide is thinking a carb is superior, I mean they basically are just fancy leaks generally


Yeah, the car still runs like that but it runs like trash, that's why carbs are the best, we all need to hold the brake, clutch and blip the throttle, and have it not start or idle in the cold and damp weather. I mean I just love stuff that has to be constantly messed with when I want to go to the store.

If that’s the way your carb’d stuff runs it’s YOU that can’t tune.

Yep, people love pissing away money to get nothing out of it when they're just commuting to work, sitting in traffic. Even a slant six A-body in good tune struggles to get 20 mpg when you can literally buy a bunch of cars now that get 30 mpg and make 1.5x the HP at the same time and hit 60 4 seconds faster, despite weighing more.

They also love waiting on inferior technology. They also love it when their mechanical fuel pump fails and washes out their oil and wrecks their rings and bearing, or that it has to run richer to not stumble and wear the rings out. The control is worse, you'll have to change the oil more often, you'll put more fuel in the cylinders with the accelerator pump, and it'll go out of tune faster.

Again, how often does a fuel pump fail? I’ve had way more electric fuel pumps fail then mechanical pumps.

Even my snowblower needs that "idiotic moronic choke" to start in the cold and run right when its not warmed up. It's just a way to do fuel enrichment.



Yep, keep looking at what percentage of cars driving around have carbs on them, its Dec/Jan here in MI and its going to be less than 1% of the cars driving around right now. There are barely any carb cars left on the road that are driven often, let alone daily. Most of the carb cars are long crushed. Nobody wanted most of them that weren't cool looking 20 years ago. The amount of cars that went to the wrecking yards due to EFI is about zero. Most of those cars are there due to rust, transmission failure, or just plain being worn out. At the same time its not even uncommon for me to see an 88-91 Chevy Pickup with a TBI even here any time of the year.

Find me an OEM car with a carb that has 400k miles that hasn't been rebuilt. Just find it. Not even hard with EFI.

My first DD had 187k miles on it with MPFI and the car was a 1988 and the car ran flawlessly. The car went to the salvage yard due to rust.

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yellow rose said:

Unreal. Not worth responding other than to ask you how many hours do you have on a dyno? At the track?

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pishta said:

Never enough.... Were still talking street cars, right? Are any of these points invalid? Carter put an altitude compensator on the later Thermoquads because they thought it would help high altitude AFR's. Feedback carburetors were developed to tighten emissions by monitoring and increasing the combustion percentage. EGR allowed engines to run cooler and decrease NOx. All of these were evolutionary to the original carburetor, and all of these are now controlled in a dynamic fashion with EFI. How about a race profile with an optimum line lock, rev limit (even shift capabilities) or nitrous window with built in retard based on RPM...and then a street profile that doesnt include any of this track stuff? You can have the best race tune and the best street tune literally at the touch of a button on a screen of a tablet or even your phone. A NASCAR spare motor doesnt make a good street motor.

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my68barracuda said:

Interesting comment that FI is only about emissions and fuel economy. Totally ignores the fact that since MPFI has been broadly used in new car production there has been a marked uptick in motor performance, across the board.

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Phreakish said:

Mpfi has been a proven power loser. The reason is latent heat of vaporization. Fuel evaporates and cools the intake charge which densifies it and helps power. In an Mpfi system the fuel doesn't evaporate in the plenum, so the plenum is hotter and less dense.

Modern engines make big power these days by leveraging variable valve timing, better cylinder wall finishes, efficient oil control and because computer design and control have helped reduce the variability cylinder-to-cylinder so much that today they get away with 87octane and 10:1.

Not to mention variable intake manifold runner lengths, better flowing heads and exhaust, better performing cooling systems, tighter tolerances and improved materials. Just look at today's block castings compared to the old iron we deal with and tell me the 70s was a good time for casting (it wasn't).

Tbi systems should be able to run as well as a carb, but they don't. Manifolds all flow different and all have balance issues unless breathed on heavily by someone well versed in porting. Carbs are self balancing to an extent, because they only add fuel based on airflow conditions through the barrels, not based on some one-size-fits-all algorithm that needs to "learn" your engine.

I'm a lover of efi in the philosophical sense, but I've come to realize in the past two years that there's a reason Detroit got away from TBI in a hurry.. Mpfi brings other challenges and a need for more and better airflow in the intake manifold (and optimizing the heads for it would also require changes), but it seems to be the only real way to go if one expects to maintain the driveability of a carb and reap all the modern benefits of efi. Since most good Mpfi systems cost 2x what the tbi systems do, it really becomes tough to find any value when a well sorted carb is probably 75% the cost of a tbi system, but it's performance is likely smack dab between tbi and Mpfi..

I'd run a tbi on a 4x4 or very very mild (stock cam) motor all day long though. It makes most sense in a 4x4 (to me) since they tend to see all kinds of odd angles and steep inclines.

Just my humble opinion, of course.

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famous bob said:

no one even mentioned going to 8000 ft sea level from 5-600 ft , ur carb ain`t gonna handle that !!

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yellow rose said:

...I do know how we are getting so far off what the OP asked.

Is EFI worth the extra money. I say no. It’s that simple really.

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lead69 said:

I would like to see the back to back results vs carbs. Also its important to note the type of build and budget. I am not anti efi but like anything to paint it with a broad brush and say its an upgrade period is incorrect. I recognize that there are allot of guys wanting to have the cake and eat it too but to say it is a better option depends on many things. For most like myself there is no benefit to the price/effort to convert to efi, it will not make more power and affect drivability enough for the conditions I drive it in to be worth while.

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