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Engine Masters has a new video out with a second round of A/B testing of Carb vs. EFI. I was surprised at the results.
I don’t think it’s made it to YouTube yet, but if you have the Motor Trend app, you can find it there. I’ve learned a lot from those guys.....definitely worth watching.
Well, that’s like telling how the movie ends before you watch it. 😆
However, there’s enough explanation to make both sides feel good about their choice.
Heres what’s been posted so far on you tube......it is NOT the whole conclusion.
Engine Masters has a new video out with a second round of A/B testing of Carb vs. EFI. I was surprised at the results.
I don’t think it’s made it to YouTube yet, but if you have the Motor Trend app, you can find it there. I’ve learned a lot from those guys.....definitely worth watching.
What was surprising about the results? I watched it earlier and remember thinking the results were pretty much how they should be. But maybe I missed part of it, I tend to watch those shows while working on something else.
Sorry, but I didn’t have any preconceived notions or ideas on how the comparison “should” turn out.
I found it informative for future considerations with my cars. I thought others might as well.
Actually that is surprising. Many people spend plenty of $$ and time to convert to EFI and a carb still makes more power.
I was not considering EFI, it’s nice to see that old tech can still hold it’s own.
the carb used and tune of that carb would make a difference I would think. The Q-jet is really efficient at part throttle and still makes good power WOT.
That clip doesn't mean much without knowing what they changed between tests.
It doesn't give the difference either, but paying attention to the carb test graph it looked like about 8 ft-lbs and 5hp difference. With a 475hp engine you wouldn't feel the difference on the street.
I'll still stick with EFI, even if it causes a small loss of power, it's wins in pretty much every way related to drive-ability.
Is that any data show the air/fuel ratio for the two, as this could account for the difference?
Same thing for the CFM rating?
The whole 20 minute video had a lot of data, air/fuel ,timing etc. Two carbs were used, and one was exact cfm and bore size as the throttle body. The same intake manifold was used for all three. The 750 cfm carb produced nearly the same dyno results.....just a hair less overall. But the 1000 cfm carb slightly exceeded the 1000 cfm EFI...
Motor Trend apparently doesn’t allow posting the whole video for a certain period of time. Too bad. The overall conclusion by the fake news perpetrators, was that EFI was definitely the way to go for those running nitrous, supercharging, or turbos. But without those, the carb held its own. Also a good point was made about carb tuning. I got a lot out of it.
Sorry, but I didn’t have any preconceived notions or ideas on how the comparison “should” turn out.
I found it informative for future considerations with my cars. I thought others might as well.
If you had no preconceived notions about it, then how did the results surprise you?
I'm just messing with you, it really is a good video and I enjoy the engine masters series. I think most people who know anything about carbs vs EFI would know the results of this one, but it is nice to see the actual numbers and see it done well where they use all the same parts and try to use similar induction.
Did they say anything about the low rpm, low throttle drive-ability of that 1000cfm carb?
You should go watch the episode, it's only like 20 minutes and has some interesting data. I don't believe they reference the driveability aspect of the different carb setups.
If you had no preconceived notions about it, then how did the results surprise you?
I'm just messing with you, it really is a good video
It’s all good, but that’s a fair question. The old adage about more HP requiring more $$$$’s isn’t always true. I was surprised to see the carbs hold their own throughout those test.
Originally Posted by lionelhutz
Did they say anything about the low rpm, low throttle drive-ability of that 1000cfm carb?
After they ran the 1000 cfm carb, there was a brief discussion on needing more converter for it. There was general acknowledgement that the 750 would be the better carb for that particular motor. The drivability of the 1000cfm EFI was said to be better than the 1000 cfm carb, all things being equal.
It’s all good, but that’s a fair question. The old adage about more HP requiring more $$$$’s isn’t always true. I was surprised to see the carbs hold their own throughout those test.
I think this case is a bit different in that no one is really buying EFI to make more peak power. Most want it for power "under the curve" and for efficiency and ease of starting/driving/tuning. A carb iis easy to tune well for a certain condition (Wide open throttle in this case) so as long as it is setup well, EFI won't hold any advantage there ever. It's alot harder to get a carb to have optimal A/F ratio at all throttle positions and conditions. I'm a big fan of the Qjet and I worked on mine extensively and modified it quite a bit via Cliff Ruggles book. I have a Wideband 02 in my exhaust to monitor A/F ratio to show me where I needed to work on my tune. I feel I got it to as good a point as I could, about 12.5:1 at WOT, 15:1 cruise, 14:1 idle, but I still have a bit of that "Carb smell" in the garage, it still isn't as easy to just start up and drive like EFI, and I guarantee that even if I make the same peak power as an EFI unit, it would have smoother throttle response and more torque at different points where my tuning wasn't optimal.
Sorry for the long-winded post, it is something fresh on my mind as I am in the process of converting to FAST efi right now! Fuel system and wiring are done, so first start up should be tonight, so I guess I will have a more accurate comparison of carb to EFI then! So far, I am loving having a handheld unit where I can change my A/F ratio at any time with a click of a button instead of having to take the top off the carb and figure out the right jet/rod combo!
Where EFI really wins is when you have a car that can sit for a long period. With EFI you do not have the issue of the bowl/needle and seat being gummed up from ethanol. Performance is close enough for me.
I have been running a carb for years but with prices of EFI systems coming down I think I'll make the move to EFI. My car is not a daily driver and can sit for months. Tired of dealing with ethanol issues. I don't like adding other chemicals to the tank to deal with ethanol as I don't know how toxic they are when burned.
Where EFI really wins is when you have a car that can sit for a long period. With EFI you do not have the issue of the bowl/needle and seat being gummed up from ethanol. Performance is close enough for me.
I have been running a carb for years but with prices of EFI systems coming down I think I'll make the move to EFI. My car is not a daily driver and can sit for months. Tired of dealing with ethanol issues. I don't like adding other chemicals to the tank to deal with ethanol as I don't know how toxic they are when burned.
You can still have that same issue. EFI may not have the needle and seat to get stuck, but your injectors can (and do) still get clogged up with the crap if they sit.
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!
09-20-2018, 09:24 AM
Carb vs. EFI
