Carb vs. EFI
09-21-2018, 10:40 AM
#21
Le Mans Master
Member Since: Apr 2001
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I commented already on motortrendondemand site that I want to see direct comparison on same engine with same intake between carb and say Sniper EFI. Not this intake that was used in this episode but say Edelbrock performer rpm intake and then test head to head carb and efi!
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Primoz (09-21-2018)
09-21-2018, 02:58 PM
#22
Melting Slicks
You have to dig really hard to find a "win" in the carb category with the current gen EFI systems. All these tests are so far from the real life conditions that most real cars will see and EFI pulls ahead by miles there.
The primary factors that have caused carbs to manage to hold on close to EFI in these tests are:
1. Better atomization
2. fuel introduced early in the intake tract == cooler / more dense air (vs port EFI anyway)
3. 100% Perfectly tuned engines/ perfectly tuned carb and ignition timing for the current dyno room they're being tested in
4. "Safe" tuning- helps the carbs look better
The newest generation of even throttle body EFI is using annular discharge holes so it's pulling air through a venturi where it meets the fuel droplets- this style EFI produces atomization identical to carbs AND fuel at the beginning of the air intake tract.
#3, IMHO, is what makes these tests the most misleading. It's NOT easy to perfectly tune the carb and few people KEEP them perfectly tuned. The "ideal" tune changes based upon air temps, fuel temps, and altitude. -Modern self-learning EFI does the tuning for you and keeps it tuned across seasons and time and can adjust for altitude and gas quality.
EFI systems can keep the AFR leaner, too producing more average power and consuming less fuel for the same power levels -if it goes too lean the knock sensor will retard the timing and save your engine.
When you look to modern higher pressure fuel sytems and the newest generation injectors that can finely atomize the fuel (or even design the jets in the injectors to collide to super atomize the fuel right infront of the intake valve) and intakes designed to flow only AIR (no design trade offs required for "Wet flow") the advantages of EFI just get bigger and bigger.
Modern EFI is starting to win even in these very narrowly defined tests where every advantage has been given to carbs.
Wide open throttle in a throttle-body application just bolted onto an old motor compared to a perfectly just tuned carb is the worst case scenario for EFI and there's almost no difference even there anymore.
Time to hold a funeral for carbs, bury them all, have a short moment of silence and move on. They belong in museums/NCRS restorations; not on cars you actually drive.
For any of the carb proponents: I'll sell you my Qjet, cheap! See FS Forum. Lol!
Adam
The primary factors that have caused carbs to manage to hold on close to EFI in these tests are:
1. Better atomization
2. fuel introduced early in the intake tract == cooler / more dense air (vs port EFI anyway)
3. 100% Perfectly tuned engines/ perfectly tuned carb and ignition timing for the current dyno room they're being tested in
4. "Safe" tuning- helps the carbs look better
The newest generation of even throttle body EFI is using annular discharge holes so it's pulling air through a venturi where it meets the fuel droplets- this style EFI produces atomization identical to carbs AND fuel at the beginning of the air intake tract.
#3, IMHO, is what makes these tests the most misleading. It's NOT easy to perfectly tune the carb and few people KEEP them perfectly tuned. The "ideal" tune changes based upon air temps, fuel temps, and altitude. -Modern self-learning EFI does the tuning for you and keeps it tuned across seasons and time and can adjust for altitude and gas quality.
EFI systems can keep the AFR leaner, too producing more average power and consuming less fuel for the same power levels -if it goes too lean the knock sensor will retard the timing and save your engine.
When you look to modern higher pressure fuel sytems and the newest generation injectors that can finely atomize the fuel (or even design the jets in the injectors to collide to super atomize the fuel right infront of the intake valve) and intakes designed to flow only AIR (no design trade offs required for "Wet flow") the advantages of EFI just get bigger and bigger.
Modern EFI is starting to win even in these very narrowly defined tests where every advantage has been given to carbs.
Wide open throttle in a throttle-body application just bolted onto an old motor compared to a perfectly just tuned carb is the worst case scenario for EFI and there's almost no difference even there anymore.
Time to hold a funeral for carbs, bury them all, have a short moment of silence and move on. They belong in museums/NCRS restorations; not on cars you actually drive.
For any of the carb proponents: I'll sell you my Qjet, cheap! See FS Forum. Lol!
Adam
Last edited by NewbVetteGuy; 09-21-2018 at 02:59 PM.
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Metalhead140 (09-21-2018)
09-21-2018, 03:08 PM
#23
You have to dig really hard to find a "win" in the carb category with the current gen EFI systems. All these tests are so far from the real life conditions that most real cars will see and EFI pulls ahead by miles there.
The primary factors that have caused carbs to manage to hold on close to EFI in these tests are:
1. Better atomization
2. fuel introduced early in the intake tract == cooler / more dense air (vs port EFI anyway)
3. 100% Perfectly tuned engines/ perfectly tuned carb and ignition timing for the current dyno room they're being tested in
4. "Safe" tuning- helps the carbs look better
The newest generation of even throttle body EFI is using annular discharge holes so it's pulling air through a venturi where it meets the fuel droplets- this style EFI produces atomization identical to carbs AND fuel at the beginning of the air intake tract.
#3, IMHO, is what makes these tests the most misleading. It's NOT easy to perfectly tune the carb and few people KEEP them perfectly tuned. The "ideal" tune changes based upon air temps, fuel temps, and altitude. -Modern self-learning EFI does the tuning for you and keeps it tuned across seasons and time and can adjust for altitude and gas quality.
EFI systems can keep the AFR leaner, too producing more average power and consuming less fuel for the same power levels -if it goes too lean the knock sensor will retard the timing and save your engine.
When you look to modern higher pressure fuel sytems and the newest generation injectors that can finely atomize the fuel (or even design the jets in the injectors to collide to super atomize the fuel right infront of the intake valve) and intakes designed to flow only AIR (no design trade offs required for "Wet flow") the advantages of EFI just get bigger and bigger.
Modern EFI is starting to win even in these very narrowly defined tests where every advantage has been given to carbs.
Wide open throttle in a throttle-body application just bolted onto an old motor compared to a perfectly just tuned carb is the worst case scenario for EFI and there's almost no difference even there anymore.
Time to hold a funeral for carbs, bury them all, have a short moment of silence and move on. They belong in museums/NCRS restorations; not on cars you actually drive.
For any of the carb proponents: I'll sell you my Qjet, cheap! See FS Forum. Lol!
Adam
The primary factors that have caused carbs to manage to hold on close to EFI in these tests are:
1. Better atomization
2. fuel introduced early in the intake tract == cooler / more dense air (vs port EFI anyway)
3. 100% Perfectly tuned engines/ perfectly tuned carb and ignition timing for the current dyno room they're being tested in
4. "Safe" tuning- helps the carbs look better
The newest generation of even throttle body EFI is using annular discharge holes so it's pulling air through a venturi where it meets the fuel droplets- this style EFI produces atomization identical to carbs AND fuel at the beginning of the air intake tract.
#3, IMHO, is what makes these tests the most misleading. It's NOT easy to perfectly tune the carb and few people KEEP them perfectly tuned. The "ideal" tune changes based upon air temps, fuel temps, and altitude. -Modern self-learning EFI does the tuning for you and keeps it tuned across seasons and time and can adjust for altitude and gas quality.
EFI systems can keep the AFR leaner, too producing more average power and consuming less fuel for the same power levels -if it goes too lean the knock sensor will retard the timing and save your engine.
When you look to modern higher pressure fuel sytems and the newest generation injectors that can finely atomize the fuel (or even design the jets in the injectors to collide to super atomize the fuel right infront of the intake valve) and intakes designed to flow only AIR (no design trade offs required for "Wet flow") the advantages of EFI just get bigger and bigger.
Modern EFI is starting to win even in these very narrowly defined tests where every advantage has been given to carbs.
Wide open throttle in a throttle-body application just bolted onto an old motor compared to a perfectly just tuned carb is the worst case scenario for EFI and there's almost no difference even there anymore.
Time to hold a funeral for carbs, bury them all, have a short moment of silence and move on. They belong in museums/NCRS restorations; not on cars you actually drive.
For any of the carb proponents: I'll sell you my Qjet, cheap! See FS Forum. Lol!
Adam
However there are a couple reasons carbs are still crazy popular and people are still buying new ones: price and ease. EFI kits are coming down in price (you can get one for $1,000 or so) but after you consider the fuel system work (couple hundred dollars at a minimum if you do it yourself) and most people upgrading their ignitions at the same time, EFI is dang expensive. Plus some people really do like a carb on their old car (though I gotta say, most people who say they PREFER a carb over an efi conversion haven't driven an old car with a good EFI conversion. It's really slick).
I can see both sides on this one as I spent a ton of time tuning my Qjet and got it running as well as I could. I would still be rocking the Qjet right now if it wasn't for a deal I couldn't pass up on a used EFI setup.
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Metalhead140 (09-21-2018)
09-21-2018, 03:20 PM
#24
Le Mans Master
I think the majority of the public switch to EFI for every reason besides more power.... Most switch to EFI for:
1) Better cold starts with no fiddling
2) The ability to maintain a consistent idle speed when running an automatic, trans, electric fans etc without having to set the idle speed HIGH in Park and dial in the drop.
3) Consistent performance in different weather conditions, hot summer to cold winter etc, also when driving in different altitude changes often.
4) Better fuel mileage, no doubt that constant fueling changes to maintain lean cruise AFR (14.7 or so) will yield better mpgs.
5) They can't tune a carb, or are tired of leaky gaskets, sticky needles etc etc.
6) Tired of dealing with vapor lock in hot climates and getting stranded...(although this can happen with EFI also)
That being said, I've NEVER had an EFI car with better driveability and response then a well dialed in carb....( I tune EFI stuff and carbs). I can fix a carb at any part store I can coast into and can be back on the road without calling a tech line and/or overnighting sensors etc.
When actually out driving on the road/city etc, my carbs are always just as smooth, transition as smooth and are usually more responsive then the EFI stuff. And typically, cars are usually faster with the carb vs the EFI assuming the carb is tuned correctly. The cooling affect on the incoming air from the fuel flowing through the boosters creates a big drop in air temps = more power.
All that being said, as cheap as EFI systems are now days, If you are about to buy a $800 850 double pumper carb new, you may should look at the affordable EFI systems.
My MAIN reason for switching to EFI personally, is better idle speed control during load changes...(Going from Park to Drive, turning the AC on, fan kicking on etc etc). Also likely better idling in high temps. Lastly, I won't smell like gas when I tune it.
You can't go wrong with either carb or EFI, and I certainly wouldn't be ripping off carbs and chunking them in the trash to throw a FITECH on one, but if I'm about to spend $1200 on a new 1050HP carb, I may look at that 4500 Sniper EFI for $500 more and never change a jet again.
1) Better cold starts with no fiddling
2) The ability to maintain a consistent idle speed when running an automatic, trans, electric fans etc without having to set the idle speed HIGH in Park and dial in the drop.
3) Consistent performance in different weather conditions, hot summer to cold winter etc, also when driving in different altitude changes often.
4) Better fuel mileage, no doubt that constant fueling changes to maintain lean cruise AFR (14.7 or so) will yield better mpgs.
5) They can't tune a carb, or are tired of leaky gaskets, sticky needles etc etc.
6) Tired of dealing with vapor lock in hot climates and getting stranded...(although this can happen with EFI also)
That being said, I've NEVER had an EFI car with better driveability and response then a well dialed in carb....( I tune EFI stuff and carbs). I can fix a carb at any part store I can coast into and can be back on the road without calling a tech line and/or overnighting sensors etc.
When actually out driving on the road/city etc, my carbs are always just as smooth, transition as smooth and are usually more responsive then the EFI stuff. And typically, cars are usually faster with the carb vs the EFI assuming the carb is tuned correctly. The cooling affect on the incoming air from the fuel flowing through the boosters creates a big drop in air temps = more power.
All that being said, as cheap as EFI systems are now days, If you are about to buy a $800 850 double pumper carb new, you may should look at the affordable EFI systems.
My MAIN reason for switching to EFI personally, is better idle speed control during load changes...(Going from Park to Drive, turning the AC on, fan kicking on etc etc). Also likely better idling in high temps. Lastly, I won't smell like gas when I tune it.
You can't go wrong with either carb or EFI, and I certainly wouldn't be ripping off carbs and chunking them in the trash to throw a FITECH on one, but if I'm about to spend $1200 on a new 1050HP carb, I may look at that 4500 Sniper EFI for $500 more and never change a jet again.
Last edited by ajrothm; 09-21-2018 at 03:24 PM.
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Metalhead140 (09-21-2018)
09-21-2018, 03:48 PM
#25
Melting Slicks
That being said, I've NEVER had an EFI car with better driveability and response then a well dialed in carb....( I tune EFI stuff and carbs). I can fix a carb at any part store I can coast into and can be back on the road without calling a tech line and/or overnighting sensors etc.
I've never known anyone who could properly dial in a carb (even though I have known tons of supposed "Hot Rodders" and old car enthusiasts); sure they could set a marginally acceptable AFR and turn the idle screw, but tuning the carb was something you took your car to a shop for once every 5 - 10 years and had them "dial-it-in" and there was never any way to validate whether it was actually done well or at all other than Placebo Effect.
All these old carb guys just fiddle with it and guess; I've never seen one even use an O2 meter. Too many duct tape "good enough" "carb tuners".
I AM one of those people who finds comfort in the objectivity of hard #s, though, admittedly. EFI and O2 meters give you an AFR as a number; most carb tuners just give you "yea, it was kinda lean; now it's kinda fat"... "The exhaust was extra stinky, now it's only mostly stinky." "Your tea leaves / spark plugs used to be blueish blackish and now they have good karma and are silvery blue". -Feel more like fortune telling, than engine tuning to someone younger and used to modern technology and hard numbers...
"You need a #50 jet" sounds like "just take 2 of these cobra blood pills twice daily" to me.
Just doesn't give me any confidence.
Adam
Last edited by NewbVetteGuy; 09-21-2018 at 03:54 PM.
09-21-2018, 04:31 PM
#26
Le Mans Master
I've had the opposite experience. I don't think I've ever experienced a carbed vehicle that was well tuned and dialed-in. (Or "It WAS 2 years ago, but now it's not driving right; I'll need to take it back to the shop / voodoo witch doctor for another carb tune-up".)
I've never known anyone who could properly dial in a carb (even though I have known tons of supposed "Hot Rodders" and old car enthusiasts); sure they could set a marginally acceptable AFR and turn the idle screw, but tuning the carb was something you took your car to a shop for once every 5 - 10 years and had them "dial-it-in" and there was never any way to validate whether it was actually done well or at all other than Placebo Effect.
All these old carb guys just fiddle with it and guess; I've never seen one even use an O2 meter. Too many duct tape "good enough" "carb tuners".
I AM one of those people who finds comfort in the objectivity of hard #s, though, admittedly. EFI and O2 meters give you an AFR as a number; most carb tuners just give you "yea, it was kinda lean; now it's kinda fat"... "The exhaust was extra stinky, now it's only mostly stinky." "Your tea leaves / spark plugs used to be blueish blackish and now they have good karma and are silvery blue". -Feel more like fortune telling, than engine tuning to someone younger and used to modern technology and hard numbers...
"You need a #50 jet" sounds like "just take 2 of these cobra blood pills twice daily" to me.
Just doesn't give me any confidence.
Adam
I've never known anyone who could properly dial in a carb (even though I have known tons of supposed "Hot Rodders" and old car enthusiasts); sure they could set a marginally acceptable AFR and turn the idle screw, but tuning the carb was something you took your car to a shop for once every 5 - 10 years and had them "dial-it-in" and there was never any way to validate whether it was actually done well or at all other than Placebo Effect.
All these old carb guys just fiddle with it and guess; I've never seen one even use an O2 meter. Too many duct tape "good enough" "carb tuners".
I AM one of those people who finds comfort in the objectivity of hard #s, though, admittedly. EFI and O2 meters give you an AFR as a number; most carb tuners just give you "yea, it was kinda lean; now it's kinda fat"... "The exhaust was extra stinky, now it's only mostly stinky." "Your tea leaves / spark plugs used to be blueish blackish and now they have good karma and are silvery blue". -Feel more like fortune telling, than engine tuning to someone younger and used to modern technology and hard numbers...
"You need a #50 jet" sounds like "just take 2 of these cobra blood pills twice daily" to me.
Just doesn't give me any confidence.
Adam
But honestly, tuning the engine for the best driveability and tuning the engine for the "best" or "proper" AFR are two different things. Give the engine what it wants, not what you THINK it wants, or what the interwebz tells you the proper AFR should be.
If you drove my 71' around town, you would swear its EFI, except more responsive....but if you looked at my wideband O2, you would be appalled. Not all engines want to run at stoich afr (14.7) which is what most closed loop EFI systems target.
Is there some fuel economy left on the table? sure... But it definitely doesn't buck/surge like a lot of EFI cars do with closed loop running and a big cam. I've tuned quite a bit on LS stuff using HP Tuners, I've also seeked the help of some of the best tuners locally, and none of the big cammed LS stuff drives as good as my ole rat motor with a carb...that makes way more power.
Even on some of the LS stuff, I've ran them in open loop at 13.5 AFR cruise as opposed to 14.7 and they drive 10X better...Yet that is wrong compared to what the interweb says.
Remember carbs have been around for over 100 years....and traveled millions of miles...they CAN be reliable and efficient, as well as make good power.
Will you ever get a carb to have the "proper" AFR at all times? no... But will you feel it in the car, no... And even if you did dial in the perfect AFR at cruise, how much MPG would you REALLY pick up?
I know guys with 502s that switched to EFI over their box stock 850 carb and gained 2 mpg on the high way with a "perfect" 14.7 afr... yes a whole 2 mpg.
Last edited by ajrothm; 09-21-2018 at 04:36 PM.
09-21-2018, 04:40 PM
#27
Le Mans Master
People that can dial in a carb are admittedly far and few between. I think most don't understand that there are more circuits in the carb than just the idle adjustment screws or they are simply intimidated by the perceived complexity of the carb.
I personally know nothing about aftermarket EFI and really don't need to to in order to get it to run correctly. That, I suppose, is what makes EFI attractive.
I however enjoy the learning process and the knowledge that is obtained by using the carb. I knew nothing about my Q-jet when I tore into it, but with Cliff Ruggles book and some common knowledge I was able to make an excellent running carb in the end.
Just like the guy who enjoys building his own motor vs buying a ready to go crate motor. It's about the process,and the learning, and now forever more you know how to make adjustments to get the desired result you may be looking for.
Sure it's old tech, so what? it works really well. It also belongs with the era of the car. I like that. Same reason I have a SBC instead or a new LS motor or some other version of motor that didn't belong with that era of car.
And carbs just look good IMO.
Is EFI superior in fuel delivery throughout the rpm spectrum in changing conditions?, yes,without a doubt.
I personally know nothing about aftermarket EFI and really don't need to to in order to get it to run correctly. That, I suppose, is what makes EFI attractive.
I however enjoy the learning process and the knowledge that is obtained by using the carb. I knew nothing about my Q-jet when I tore into it, but with Cliff Ruggles book and some common knowledge I was able to make an excellent running carb in the end.
Just like the guy who enjoys building his own motor vs buying a ready to go crate motor. It's about the process,and the learning, and now forever more you know how to make adjustments to get the desired result you may be looking for.
Sure it's old tech, so what? it works really well. It also belongs with the era of the car. I like that. Same reason I have a SBC instead or a new LS motor or some other version of motor that didn't belong with that era of car.
And carbs just look good IMO.
Is EFI superior in fuel delivery throughout the rpm spectrum in changing conditions?, yes,without a doubt.
09-21-2018, 08:35 PM
#28
Drifting
lol that was funny.. especially when WC claims it was because he was on wet grass and they were on concrete..lol reminds me of when my son was 4 yrs old and tried to explain how it wasn't his fault the cookie jar got broken when his chair turned over getting it .....
09-21-2018, 09:50 PM
#29
Race Director
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EFI tuning - sit in the drivers seat, never open the hood, never remove the air breather, never get gas all over my hands. It's not a bad way to tune.
Same with electronic transmissions. No need to be lying under a car pulling the governor or removing the pan to change their operating characteristics.
Same with electronic transmissions. No need to be lying under a car pulling the governor or removing the pan to change their operating characteristics.
09-21-2018, 11:50 PM
#30
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2020 C2 of the Year - Modified Winner
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Carburetors still work well. They are simple and respond. I think most people screw up more than they should by messing with them. I can't tell you how many carbs I've "fixed" by looking up the original configuration and returning it to stock. When I lived in Denver I had a sideline going by picking up carbs at the swap meet for near nothing...fixing them and re-selling. Everyone felt the need to lean them out like crazy for the altitude. Once you spend a little time figuring out what does what...you make them do what you want. My old '68 SS Nova ran around with a tunnel ram and 660 center squirters on the street as my daily driver. (14x32's/four speed and 5.38 gears). It took a little work with some lead from a shotgun shell plugging and redrilling holes...and softening the throttle linkage from being 1 to 1...but it never fouled a plug and those things screamed!
My 540/555 ran for years with my homebuilt 1050 Dominator. Added a PV and PVCR's to front side and dropped jets 8 sizes, added "soft" progressive linkage and a few other minor mods and it drove incredible. Plugs literally lasted years and it never burped or spit. When I teamed with Holley to do some back to back testing on the dyno with Holley's Dominator EFI..I wasn't sure what to expect. Back to back..power was about identical. But what was neat was that in a few quick dyno pulls and a few keystrokes...the dyno runs were near identical...vs the years of tuning/experience I had getting the carb perfected.
The lesson I took from that is that not everyone has the ability or "inclination to learn" how to play with carbs...especially now days where no one has seen a carb from an OEM. What was it...about 1985 when carbs were done? That's 33 years ago! I see many folks spend huge $$$ on a bad boy engine...yet end up hating it because it drives like crap and then the first time they kick it..all the plugs are fouled and their buddy runs off and hides from them. In those cases...certainly a good self tuning EFI system will allow people to actually enjoy their cars and run like they should.
I've had EFI on my Vette for years now. I had a TPS sensor die once and it defaulted to full rich. I found one at the parts store but it was wound backwards so I couldn't use it on the throttle body. But I WAS able to plug it in, do a manual reset with a screwdriver turning the switch...and then just lay it on the manifold. The tables were already pretty filled in from the learning features and it drove perfectly just using inputs from the MAP sensor. That's pretty impressive.
Another neat feature of EFI is the versatility. When I switched to turbos, I bought another MAP sensor for boost and downloaded a new base tune from the Holley database within the program. It fired up instantly and from there I made some tweaks and all was good.
I still love playing with carbs and points and solid lifter cams and stick transmissions...but there are cool things you can do with new technology!
JIM
My 540/555 ran for years with my homebuilt 1050 Dominator. Added a PV and PVCR's to front side and dropped jets 8 sizes, added "soft" progressive linkage and a few other minor mods and it drove incredible. Plugs literally lasted years and it never burped or spit. When I teamed with Holley to do some back to back testing on the dyno with Holley's Dominator EFI..I wasn't sure what to expect. Back to back..power was about identical. But what was neat was that in a few quick dyno pulls and a few keystrokes...the dyno runs were near identical...vs the years of tuning/experience I had getting the carb perfected.
The lesson I took from that is that not everyone has the ability or "inclination to learn" how to play with carbs...especially now days where no one has seen a carb from an OEM. What was it...about 1985 when carbs were done? That's 33 years ago! I see many folks spend huge $$$ on a bad boy engine...yet end up hating it because it drives like crap and then the first time they kick it..all the plugs are fouled and their buddy runs off and hides from them. In those cases...certainly a good self tuning EFI system will allow people to actually enjoy their cars and run like they should.
I've had EFI on my Vette for years now. I had a TPS sensor die once and it defaulted to full rich. I found one at the parts store but it was wound backwards so I couldn't use it on the throttle body. But I WAS able to plug it in, do a manual reset with a screwdriver turning the switch...and then just lay it on the manifold. The tables were already pretty filled in from the learning features and it drove perfectly just using inputs from the MAP sensor. That's pretty impressive.
Another neat feature of EFI is the versatility. When I switched to turbos, I bought another MAP sensor for boost and downloaded a new base tune from the Holley database within the program. It fired up instantly and from there I made some tweaks and all was good.
I still love playing with carbs and points and solid lifter cams and stick transmissions...but there are cool things you can do with new technology!
JIM
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maj75 (09-30-2018)
09-22-2018, 02:30 AM
#31
Burning Brakes
EFI is great but the costs are misleading.First you need the Sniper TBI 999.00.Then the fuel system ,I have a RobbMC Powersurge 300.00 .You should upgrade the ignition system to work with the Sniper to get the full benefits, cost with the Dual Sync Dist,Coil & CD box 350.00.
Your gonna need a laptop to fine tune it.My Sniper needed to be tweaked with a laptop to run right .When its all said and done it is worth it if you like great street manners ..Those dyno tests dont take into consideration changes in altitude, changes in temperature,stop and go traffic.The EFI is awesome for a street driven car.Instant starts hot or cold too! I drive my Vette quite a bit had a few carbs on it but the EFI really made driving her that much better.....
Your gonna need a laptop to fine tune it.My Sniper needed to be tweaked with a laptop to run right .When its all said and done it is worth it if you like great street manners ..Those dyno tests dont take into consideration changes in altitude, changes in temperature,stop and go traffic.The EFI is awesome for a street driven car.Instant starts hot or cold too! I drive my Vette quite a bit had a few carbs on it but the EFI really made driving her that much better.....
09-22-2018, 09:41 PM
#32
Team Owner
EFI systems are generally "Plug n Play". But that doesn't mean they work WELL when you just "Plug n Play". EFI systems have to be dialed in to work well during all aspects of driving, as well. And, most folks aren't 'techie' enough to do that well, either.
Both systems work well when dialed in for the engine and application required. It takes knowledge and skill to optimize the performance of either carb or EFI system. To each his/her own regarding which is "best".
Both systems work well when dialed in for the engine and application required. It takes knowledge and skill to optimize the performance of either carb or EFI system. To each his/her own regarding which is "best".
09-22-2018, 10:59 PM
#33
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I think the majority of the public switch to EFI for every reason besides more power.... Most switch to EFI for:
1) Better cold starts with no fiddling
2) The ability to maintain a consistent idle speed when running an automatic, trans, electric fans etc without having to set the idle speed HIGH in Park and dial in the drop.
3) Consistent performance in different weather conditions, hot summer to cold winter etc, also when driving in different altitude changes often.
4) Better fuel mileage, no doubt that constant fueling changes to maintain lean cruise AFR (14.7 or so) will yield better mpgs.
5) They can't tune a carb, or are tired of leaky gaskets, sticky needles etc etc.
6) Tired of dealing with vapor lock in hot climates and getting stranded...(although this can happen with EFI also)
That being said, I've NEVER had an EFI car with better driveability and response then a well dialed in carb....( I tune EFI stuff and carbs). I can fix a carb at any part store I can coast into and can be back on the road without calling a tech line and/or overnighting sensors etc.
When actually out driving on the road/city etc, my carbs are always just as smooth, transition as smooth and are usually more responsive then the EFI stuff. And typically, cars are usually faster with the carb vs the EFI assuming the carb is tuned correctly. The cooling affect on the incoming air from the fuel flowing through the boosters creates a big drop in air temps = more power.
All that being said, as cheap as EFI systems are now days, If you are about to buy a $800 850 double pumper carb new, you may should look at the affordable EFI systems.
My MAIN reason for switching to EFI personally, is better idle speed control during load changes...(Going from Park to Drive, turning the AC on, fan kicking on etc etc). Also likely better idling in high temps. Lastly, I won't smell like gas when I tune it.
You can't go wrong with either carb or EFI, and I certainly wouldn't be ripping off carbs and chunking them in the trash to throw a FITECH on one, but if I'm about to spend $1200 on a new 1050HP carb, I may look at that 4500 Sniper EFI for $500 more and never change a jet again.
1) Better cold starts with no fiddling
2) The ability to maintain a consistent idle speed when running an automatic, trans, electric fans etc without having to set the idle speed HIGH in Park and dial in the drop.
3) Consistent performance in different weather conditions, hot summer to cold winter etc, also when driving in different altitude changes often.
4) Better fuel mileage, no doubt that constant fueling changes to maintain lean cruise AFR (14.7 or so) will yield better mpgs.
5) They can't tune a carb, or are tired of leaky gaskets, sticky needles etc etc.
6) Tired of dealing with vapor lock in hot climates and getting stranded...(although this can happen with EFI also)
That being said, I've NEVER had an EFI car with better driveability and response then a well dialed in carb....( I tune EFI stuff and carbs). I can fix a carb at any part store I can coast into and can be back on the road without calling a tech line and/or overnighting sensors etc.
When actually out driving on the road/city etc, my carbs are always just as smooth, transition as smooth and are usually more responsive then the EFI stuff. And typically, cars are usually faster with the carb vs the EFI assuming the carb is tuned correctly. The cooling affect on the incoming air from the fuel flowing through the boosters creates a big drop in air temps = more power.
All that being said, as cheap as EFI systems are now days, If you are about to buy a $800 850 double pumper carb new, you may should look at the affordable EFI systems.
My MAIN reason for switching to EFI personally, is better idle speed control during load changes...(Going from Park to Drive, turning the AC on, fan kicking on etc etc). Also likely better idling in high temps. Lastly, I won't smell like gas when I tune it.
You can't go wrong with either carb or EFI, and I certainly wouldn't be ripping off carbs and chunking them in the trash to throw a FITECH on one, but if I'm about to spend $1200 on a new 1050HP carb, I may look at that 4500 Sniper EFI for $500 more and never change a jet again.
Not that he wasn't a carb guru, he was but he liked all the pros efi gives, ( ge didnt like points either )
Drove it about 30 years daily driver 20 years,
When he was going down in 14 at 89 and asked me to sell his car, the new owner is still running that pro jection with no issues,
And compared to modern efi its Jurassic,
Me, im old school gonna give a qjet a whirl that a kind member gave me
09-23-2018, 01:30 AM
#35
Le Mans Master
A Tri power unit will be super cool as well.
I'm really eye balling that 4500 Sniper unit....
Whats weird is there seems to be a power range gap in the Holley systems. Most of the Sniper/HP systems are good to 600 hp or so...Then the 4500 Sniper is good for 800+ but ofcourse requires a 4500 intake and a Dominator style air cleaner which will not drop base. I wish they made a 4150 style that supported 750hp.... I'd be all over it.
09-30-2018, 01:30 PM
#36
Burning Brakes
I grew up when 95% of the cars had carbs. They went millions of miles. I remember when folks removed the fuel injection from their Porsches and put on Weber carbs.
My ‘69 427 starts and runs just fine with its Qjet. Carbs need to be used. If the car sits for long periods, like many C3s do, then you may run into problems. Unfortunately, it’s almost impossible to find a mechanic that knows anything about carbs. If you can’t plug a computer into it and have the computer tell you what’s wrong, most “technicians” are lost. However you can usually fix a carb on the side of the road with a couple of wrenches and a screwdriver. Not your EFI when it quits. And for me, the cost/mile of converting makes no sense, not to mention the loss of originality.
My ‘69 427 starts and runs just fine with its Qjet. Carbs need to be used. If the car sits for long periods, like many C3s do, then you may run into problems. Unfortunately, it’s almost impossible to find a mechanic that knows anything about carbs. If you can’t plug a computer into it and have the computer tell you what’s wrong, most “technicians” are lost. However you can usually fix a carb on the side of the road with a couple of wrenches and a screwdriver. Not your EFI when it quits. And for me, the cost/mile of converting makes no sense, not to mention the loss of originality.