09 d8 Carb
- Thread starter brum24
- Start date
Why?
We are putting carbed Cat 900 motors in a couple dragons. One almost finished, one just starting. Probably doesn't really help you too much though. One thing I would say, is if you don't want to buy a PAR motor plate, you can just get two left side motor mounts, and weld straps between them and you've got a flat plate pretty cheap/easy.
M
mike_s
Well-known member
I'll counter with another question:why not?
Fuel injection is superior. Easier to tune, adjust for altitude, RPM, etc. When properly tuned you won't make any more power with a carb than a fuel injector.
Makes zero sense to me. Tune the fuel injection properly and it will be superior.
Makes zero sense to me. Tune the fuel injection properly and it will be superior.
B
brum24
Member
fuel injected is easier to jump on and ride but it is far from superior or easier to tune. carb motors are simple, only a few things can be wrong. Fuel injected have more electronics and more to go wrong. there are many reasons why big block motors such as watercraft, psi just a couple that stay carb motors. i have a 14 fuel injected and it is very nice but in no way superior in the motor.
M
mike_s
Well-known member
You do have a few valid points, and a few, in my opinion, that are inaccurate. For convinience, yes, efi is the way to go. I dont think many people will question that one. Altitude, tepmerature, and varying condition compensation that is automatically taken care of is never a bad thing. To say that EFI is easier to tune is a bit of a double edged sword. While it is true that if a guy has a few bolt ons such as a can, and different airbox a simple piggyback can be added and tappity tapping a few buttons is easier than removing a carb and swapping out jets. However, to say that a piggyback will outperform properly set up carbs is, in my opinion, completely inaccurate. EFI with a piggyback controller does work, in most cases, however the only thing you can do is move around the factory map that the manufacturer has already deemed proper. When Bigger modifications are performed that map is no longer accurate. When youre lean on top to correct that you move the map up and now your rich on bottom. The accuracy is simply not there. Now the counter argument is that you can get standalone units. Very true, and also very expensive and complex. With these you get stuck with, esentially the same issue, just with someone elses modified engine and tuning. Unless you have a few thousand dollars worth of hardware and software, and the understanding of how to manipulate things like MAF tables, VE tables, transient response tables and so on. The average joe sledder isnt really into all of this, and just wants to ride. Most guys arent going to understand how to tune an EFI system to respond to varying engine loads using terms that many probably have never heard of.
This is where a carburetor comes in. A carburetor, while very limited in its ability to adjust for varying temperature and altitude, is more than adept at responding to varying engine conditions. It already knows what to do when RPM drops and load increases. If You make a modification, and if its rich up top, you swap in a smaller main jet and goto town. If its rich on bottom or in the mids swap out a pilot or needle, you dont have to make changes in 4 different maps to properly address the change in volumetric efficiency. Once tuned in It adjusts fuel delivery automatically for varying engine loads, throttle position, and RPM. No need for thousands of dollars worth of electronic hardware and software, or waiting for a tuner to email you back a new tune file that will hopefully work given the fact that he hasnt had hands on your machine, or mailing off your ECM to be reflashed, or dealing with a lean or rich spot because thats the only way you can get it to run right in the sweet spot.
Now, to the biggest point of my novel. Take 2 machines. Mod them. Run one with the efi the way the majority of people are running them: with a piggyback. Slap on pipes, big porting, high compression heads, and a few other little odds and ends. Now do the same to another, but trade off the efi and piggyback for carbs. I GARANTEE the carb engine will make more power in this instance, simply because the EFI and piggyback setup just doesnt have the range of adjustability or accuracy that the carbs do. Youre still stuck moving the factory established map around on 3 points. Sure, you can swap out for a vipec, but a set of mikuni's is way less expensive, and you wont have to rely on someone else to write the tuneup for you, or invest in a system to tune it yourself while you learn all the ins and outs of setting up an EFI system to run.
Yes, EFI has its advantages, and can make more power over a broader range of altitudes and barometric pressures without being fiddled with, but to make a blanket statement that it is simply superior to other forms of Fuel metering, i feel is inaccurate.
There are several ways around the factory map. You can usually have multiple maps for different elevations, fuels, etc.
There is a reason everything in the auto world and power sports world is going efi.
How well did 2stroke turbos work before efi?
There is a reason everything in the auto world and power sports world is going efi.
How well did 2stroke turbos work before efi?
S
Spaarky
Well-known member
Two stroke carb turbos were kick Azz before efi and still are. How hard is it to adjust a power jet ? Not to dang hard.
If piggy back and efi is so great why do you need all the different maps and adjustments?
IMO. there is a lot of good reasons to do the project. Heck weight savings alone would be huge. They both have positives and negatives. Personal preference.
And the answer to your question why? Reliability. We built my current set up in 08. Still has not left me stranded.
If piggy back and efi is so great why do you need all the different maps and adjustments?
IMO. there is a lot of good reasons to do the project. Heck weight savings alone would be huge. They both have positives and negatives. Personal preference.
And the answer to your question why? Reliability. We built my current set up in 08. Still has not left me stranded.
Last edited:
M
mike_s
Well-known member
Yes, there is a reason, its called the EPA.
Im not saying that either is better than the other, just saying that each has its benefits and drawbacks. EFI is great for those who are leaving their sleds stock or mostly stock. But if you get into heavy modification it becomes cumbersome.
2 stroke turbos also worked very very well using carbs before EFI was mainstream. You just dont hear about them much because the sledding world was still stuck on "a turbo cant work on a 2stroke, it will just blow straight out the exhaust! What a waste of fuel!"
Completely disagree that efi won't work on heavily modified sleds. It works perfectly fine. I rode a carbed turbo and if you got on and off and back on the throttle many times the pressure would blow the fuel right out of the bowls. You can flip an efi sled upside down and it still run.
M
mike_s
Well-known member
EFI does work great on modified engine, when its implimented properly. What im saying is you wont realize the full performance potential of those mods with the factory ecm and a piggyback, as the majority of people are running them. And to get to the point that you will is usually cost prohibitive to most people.
If a carbureted turbo is blowing fuel out of the float bowls, then it needs to be redesigned the right way.
If a carbureted turbo is blowing fuel out of the float bowls, then it needs to be redesigned the right way.
B
brum24
Member
i had a 08 600 turbo on a carb motor before my efi turbo dragon and IMO the carb ran harder and was easier and more reliable. im not saying fuel injection is bad, far from i love the easiness of my 14 as well but i dont think that they have anything up on the carbed big block. just askin if anyone has done it or if anyone has suggestions. appreciate all you guys supporting this thread liking the discussions.
M
mike_s
Well-known member
Post number 8 in this thread, appears this guy has some under his belt. Might pm him for suggestions.
http://www.snowest.com/forum/showthread.php?t=374796
http://www.snowest.com/forum/showthread.php?t=374796
