482 Big block Chevrolet. Steel block and heads, 11:1 compression. Power glide with 4500 stall and 4.56:1 gears.
Door car total weight 2640lbs.
I usually run 110 octane.

I have considered going to an efi system, which one would you guys suggest for this combination. I’m looking for consistency and reliability.

What (if any) performance gains do you normally see when switching from single 4bbl. To efi?

Also considering a flying toilet. Anyone have any comparison between efi and the flying toilet?

Thanks for any help.

It's been years since I ran a carb. But a few years ago I switched from toilet to efi. Methanol in all cases.
The car was quite consistent on the toilet. And decent fast for a small block dragster. Switched to a MS3Pro Ultimate system. Moderate cost. Steep learning curve and install learning IMO. But once learned, it is powerful and flexible. It wasn't terribly consistent until I started learning the ins and outs of tuning. Eventually the car was a couple hundtreths quicker, and at least as consistent as the toilet. But it took a lot of runs to get there. Holley seems to have a system that is quicker to learn and quicker to get to good runs. A friend used one of the larger holley throttle body units and had some setup help. He was making great runs very quickly with some help from the self tuning. Having help that knows the system is very beneficial.

I don’t know anything about EFI, but you could have .5 potential with a switch to injected methanol and a looser torque converter.

I don’t know anything about your engine, but 4500 stall sounds unusually low.

Alcohol works great with lower compression like 11 to 1.
If you went to EFI on gas would not expect much performance gains if any. But with EFI on gas when it is tuned right should start faster and easier. Now if you go to alcohol MFI or EFI you should see significant improvement in performance.
One of the keys to getting injection tuned right is good data what motor is doing.

I think EFI is harder to learn and get it tuned right but when you do it is much more efficient and will use less fuel and warm up quicker.

As a non techo guy. MFI is simplest thing in world and most everyone picks up some when switching. Very easy to be consistent also.
EFI is probably great once you learn the in and outs of it.IMO learning curve for me would be beyond my patience level. Not saying that it would not be great if you get it right.

Holley HP or Dominator system is what I recommend to my customers, especially if you want to run methanol. The learning curve is steep, that's why I teach my customers how to use the system, not leave them to fend for themselves. Remote tuning is another big help to getting a combination squared away. One of the biggest advantages to the EFI is that it has a built in datalogger that's better than a Racepak and ignition control that's better than a Grid. Plus they have a digital dash available that's WAAAYYY better than a Racepak dash.
EFI won't be any faster than a carburetor (unless the carb is leaving something on the table), but it will be more consistent.

With gas on carb and efi they should run close to the same if the carb setup is good. I am a firm believer that the efi will be more consistent when tuned up, based on my experience. If you want to get quicker then alky will do that

Gotta say right now I am leaning towards a flying toilet from Ron’s.

Rons flying toilet or an enderle 4" single butterfly from Alkydigger. Both systems work well, methanol fuel is the easiest choice. Should pick your combination up quite a bit vs. gasoline carburetor, if i had to guess i'd say once its tuned out it will be 0.25 faster than gas carb on your application.

What et&mph do you run now?

quote:

Originally posted by botmbulb:
EFI won't be any faster than a carburetor (unless the carb is leaving something on the table), but it will be more consistent.

You state that efi is more consistent than a carb. What is your opinion of efi vs mfi (methanol) for consistency ???

Having used all three, I only have opinions based upon my experiences.
Gas carb....least consistent of the bunch.
Alky carb....we now had a car that was very consistent.
ron's injection.....faster, and maybe a click more consistent
efi.....comparable to ron's and maybe just a tad faster
Going to alky was the biggest difference of them all.

quote:

Originally posted by markemark:

quote:

Originally posted by botmbulb:
EFI won't be any faster than a carburetor (unless the carb is leaving something on the table), but it will be more consistent.

You state that efi is more consistent than a carb. What is your opinion of efi vs mfi (methanol) for consistency ???

EFI is more consistent. There are things you can do that are just simply not possible to do mechanically.

quote:

Originally posted by botmbulb:
EFI is more consistent. There are things you can do that are just simply not possible to do mechanically.

Ok, Is it possible to give 1 for instance of what that is ??

quote:

Originally posted by markemark:

quote:

Originally posted by botmbulb:
EFI is more consistent. There are things you can do that are just simply not possible to do mechanically.

Ok, Is it possible to give 1 for instance of what that is ??

Adjust fuel and/or timing based on water temp, inlet air temp, intake temp, and any other factor you want, to keep the ET from varying when conditions change. If it's a footbrake or throttle stop combination, the part throttle tuning ability cannot be touched by a carb, and is basically nonexistent with MFI. There are other things if you are willing to spend the time and money, such as individual cylinder tuning (both fuel and spark).
Please, if you have any more questions, don't hesitate to ask.

quote:

Originally posted by botmbulb:Please, if you have any more questions, don't hesitate to ask.

Viewed some Holley EFI Tech videos on Youtube today and have a general understanding of the GCF /ICF 5 items needed to allow engine to run. I then installed V5 and opened a hefi from the Base Cals to view some of the settings demonstrated on Youtube. Looking at the HP specifications which lists a single O2.

It’s apparent that the O2 sensor plays an important role in how accurately the system controls. Is location of this O2 sensor critical in making the system work properly? By this I mean is it possible to install O2 in a single pipe instead of the collector and have it work properly??

quote:

Originally posted by markemark:

quote:

Originally posted by botmbulb:Please, if you have any more questions, don't hesitate to ask.

Viewed some Holley EFI Tech videos on Youtube today and have a general understanding of the GCF /ICF 5 items needed to allow engine to run. I then installed V5 and opened a hefi from the Base Cals to view some of the settings demonstrated on Youtube. Looking at the HP specifications which lists a single O2.

It’s apparent that the O2 sensor plays an important role in how accurately the system controls. Is location of this O2 sensor critical in making the system work properly? By this I mean is it possible to install O2 in a single pipe instead of the collector and have it work properly??

Yes, you can use it in a primary or the collector. Understand that the system will maintain whatever target AFR you set the table for, whether that AFR is correct or not. Reading the plugs and looking at the mph is still what's most important.

quote:

Originally posted by botmbulb:


Yes, you can use it in a primary or the collector. Understand that the system will maintain whatever target AFR you set the table for, whether that AFR is correct or not. Reading the plugs and looking at the mph is still what's most important.

Good point do not tune to reach a stupid number on your O2. Tune to ET and MPH and then use the O2 from there. Same with timing, your timing light may be different a few degrees than others and you motor may have different needs.

I spent a lot of time on the dyno to get my tune up. Once I got that tune up I used the O2 to keep it perfect. On my motor and Data Logger it is 12.9 to 13.1 on the Gas Scale. Have been told it should be 12.0. No it is not at least not on my motor and my logger.

When I ran EGT's was told it MUST be 1050* in 1/8 mile and 1100* in the 1/4 mile. Mine was stupid fat and would not run there. Get EGT's up to 1350*-1400* and it would run. So do not let anyone tell you what number they think your car needs.

quote:

Originally posted by botmbulb:Please, if you have any more questions, don't hesitate to ask.

I have complete Grid ignition and use a crank trigger. Can all this be used to work with HP EFI ?

I'm a little different about EFI.
First, part throttle IMO isn't very useful unless you are throttle stop racing. Drag racing is just pretty simple. But you can of course adjust fuel cylinder to cylinder if you have 8 injectors. Same with timing. You can get the afr flat for the entire run with some help from self tuning suggestions to the base map.
But......
I don't trust the self adjustment completely. o2 sensors can and do go bad, or drift or get a sniff of something. So I use them to get a base tune, and then really limit how much influence the self tune can have. I may warm up to it later. But I find it predictable to have a warm weather tune and a cold weather tune.

That said, with turbos, the efi becomes absolutely limitless. You can control boost with the ecu everywhere during the run if you like.