Different Carb or EFI

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SRT_DSTRHOLC

SRT_DSTRHOLC

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I had this plan to save up for EFI. I currently have a 750 dp that I wanted to put on top of my 410 stroker, but thats if I cant find a 950hp. My question is what do you guys think would be better in the long run? The EZ kits bolt on and change CFM, so it would save money on swapping carbs, but I think I might have plans for nitrous and I do not know if there is a kit that basically bolts on while being able to use nitrous. This is a 410 stroker that should make 500hp. I seen DVJCUDA has the EZ-FAST but he is not using nitrous. The other thing is I don't really want to do an in tank fuel pump, is it possible to run the kits without it even with a return line?
 
The EFI pressure often runs at 50 PSI, however the regulators are biased by manifold pressure so the delivery pressure is nearly constant. The regulator returns the excess to the tank. A surge tank could be used, however that is much more complicated, than an in-tank pump and return line. There are system that have a needle and seat like a carb to hold tank fuel level, the mechanical fuel pump feeds the tank, with an electric pump in the bottom to feed the EFI. A return is done on the surge tank, also a vent to purge canister. The main problem beyond complexity, is room in the engine compartment to mount the surge tank.
 
I'm just trying to figure out also if it would be better to save my money for an efi or just get the 950dp. I mean it would be nice to have easier tuning and better gas.
 
There is a significant learning curve to understand the tuning process for efi. There is significant information to process, things like MAP, RPM, temperatures, throttle position WBO2, and knock. Good EFI systems with ignition controls have more adjustments than choke thermostat, jets mechanical and vacuum advance. An optimal tune requires placing correct numeric values, in the correct locations. By location, means fuel enrichments need to be done for starting prime, warm-up, temperatures, acceleration enrichments, and VE table. Similar with less complications, for ignition timing map. Done correctly, it takes time and various operating conditions. Waiting for cold weather to do a start-up/ warm-up tune, things like that. The results can be excellent, great manners, power and economy all in one. Or a disaster for some. Like most things, it is a matter of attention to details.
 
I had a '69 Valiant a few years ago with a 400 in it, I went through Rich Nedbal at Mopar Engines West to get my FAST XFI system, he'll set you up with everything you need, and I can't say enough good things about him or the XFI system. It made a WORLD of difference on my car, with cold starting, throttle response, fuel mileage. Just to play around, I would fill up with e85, and you only have to change one thing in the program to switch between gas and e85
 
When I went to the website, I did not see a "kit." is it a piece together kind of thing?
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http://www.fuelairspark.com/Products/FS-'XFI 2.0 Electronic Fuel Injection'-0.aspx

KitCarlson said:
There is a significant learning curve to understand the tuning process for efi. There is significant information to process, things like MAP, RPM, temperatures, throttle position WBO2, and knock.
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I agree but that’s what tuners are for. :D

With that the EZ EFI takes away all that learning curve needed, but you won't be able to run nitrous like you mentioned in the first post. The EZ system can’t compensate for power adders being a self tuning speed density system. My motor is currently at the machine shop being reworked. When I put it back together I will be dropping my nitrous kit and slapping on an EZ EFI. The cost isn't all that bad when you consider that you can sell off a few items to lower the cost of the EFI. It would be a good chunk of coin to get the XFI system onto a carb car starting with nothing. Than you would still have to pay for tune time if you’re not up to the task. I dropped nearly a $1000 on 2 different tuners to get my turbo mustang tuned right. Could have been less if I took it to the second guy first.

There is also the EZ EFI multiport retro kit if you wanted to steal a fuel system off a donor car, preferably a GM since the harness is wired for GM plugs car.http://www.compperformancegroupstor...re_Code=FS&Product_Code=302000&Category_Code=
 
I would check out Edelbrocks new pro flow XT EFI systems. I've also been thinking of going this route just because of the fuel efficiency and reliability not to mention how much smoother they run and throttle response is like night and day. In my opinion its a no brainer if you want to spend the money and have a engine that runs 100% better than a carbureted engine.
 
I have run the old Holley Pro-jection TBI for 20 years on my Newport. It requires constant tweaking, even with O2 feedback, especially their smaller 2Di box. Their follow on Commander 950 is supposed to be much better, with more sensors (MAP, IAT) and more tuneability. I will try on several cars when I have time. It can control TBI or MPFI, plus spark. A used system usually ~$600 on ebay, though I got an ECU alone for $125. The Avenger is Holley's latest, but ~$2000. Looks like mostly a slicker interface. Many people seem to buy systems and give up, sometimes without even trying. Makes a cheap resale market for guys like me that are resourceful but cheap.
 
I would like to do something with nitrous and Direct injection, but I have an Air Gap for a magnum and I dont know if I can drill it for injector bosses
 
What do think a EFI system would do for you? It might increase your gas mileage and drivability by a bit not really gonna increase your power output the 950hp and Nos is gonna be a quicker car and it would take a lot of years to pay back in fuel savings from the EFI system.
 
273 said:
What do think a EFI system would do for you? It might increase your gas mileage and drivability by a bit not really gonna increase your power output the 950hp and Nos is gonna be a quicker car and it would take a lot of years to pay back in fuel savings from the EFI system.
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Im only 23, I have plenty of time to take in the benefits. IF I got EFI and Nitrous, will be better then 950 and nitrous, as long as it is direct port. Easier start ups, not fuel boil over, no tuning once done. I can learn to tune with a computer, rather then take apart the carb.
 
273 said:
What do think a EFI system would do for you? It might increase your gas mileage and drivability by a bit not really gonna increase your power output the 950hp and Nos is gonna be a quicker car and it would take a lot of years to pay back in fuel savings from the EFI system.
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if the carb isn't dead balls on in its tune then the efi can and will improve performance quite a bit.


this guy saw a 5 mpg gain. and says the car feels better. said the carb ran good to. hat to be way out of tune.. http://board.moparts.org/ubbthreads/showflat.php?Cat=0&Number=7331071&an=0&page=1#Post7331071
 
abodyjoe said:
if the carb isn't dead balls on in its tune then the efi can and will improve performance quite a bit.


this guy saw a 5 mpg gain. and says the car feels better. said the carb ran good to. hat to be way out of tune.. http://board.moparts.org/ubbthreads/showflat.php?Cat=0&Number=7331071&an=0&page=1#Post7331071
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You talked about how next time you would go with a system where you could get parts from local store. What kind of system would you think of? and what would be price difference going to direct injection instead of the carb style efi?


I also got this off a site where the guy emailed FAST.
"The reason we don't advise it with nitrous oxide is because this system is always in closed loop. If you go to wide-open throttle, it tunes to your WOT air/fuel ratio target that you have set. If you spray nitrous, it doesn't know this, and it will try to keep the air/fuel ratio at the target you have selected for normally aspirated. This is normally too lean for nitrous; it would lean the mixture out to an undesirable point. There are guys running nitrous with it, but they're setting their WOT air/fuel ratio to what they want when the nitrous is on. This will obviously work for the track, and conceivably you could change the tune before you drive home-so it's possible, just not recommended."
 
I'm running the EZ EFI system right now. Love it, runs way better than before when I had a carb on the engine.
 
There is a "dead head" EFI system that looks like a carb and doesnt require a return line. Run a external inline Bosch fuel pump like off a Mercedes 450 and you should not need a sumped tank. Dont know about nitrous and you need to get the injectors to match your HP level, the stock ones probably wont do 500HP but your motor may not make 500 either...? here is an option..Megasquirt demands a huge amount of fabrication, I know, I still have an unassembled kit on a box somewhere.

http://blog.procompelectronics.com/1/post/2010/11/procomp-electronics-motorsport-turnkey-efi.html
 
EFI can have a dramatic effect on cam choice. Make sure the cam you are using for that 500hp is going to be compatible with EFI.

Buy a wideband. You will want one either way. It makes tuning a snap, carb or EFI.
 
One of the "deadhead"systems Pishta recommended :professonal Products.Wideband 02,integrated block learning skills.
 
LXguy said:
EFI can have a dramatic effect on cam choice. Make sure the cam you are using for that 500hp is going to be compatible with EFI.

Buy a wideband. You will want one either way. It makes tuning a snap, carb or EFI.
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I am going to run the carb first. I need to see if I have enough vacuum for the EFI.
 
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