EFI question

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dartboy73

dartboy73

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So I have a 2008 6.1 my question is should I go with a fast EFI system or mega squirt or the holly dominator? Are they all the same as far as ease of install and power? It will be going in my 68 fastback Cuda. Still undecided on transmission
 
Man, I was hoping someone would chime in by now. Its all a matter of how much you can do and how comfortable you are with tuning.

In a nutshell...

- $ Megasquirt has build your own, or plug and play options available. Tuning is all on you, but there is a separate tuning program out now that has self tuning as well.
- $$ Fast will be more of a bolt on install. Newer units have self tuning capability.
-$$$ Holley is a complete build your own harness system that has unreal potential. Again, tuning is on you.

There are plenty of pay-per-tune folks out there that can take care of you if thats not your specialty.

Your choice of transmission may have an effect on your final decision, as not all Mopar automatic transmissions are supported by the aftermarket.
 
cu440da pretty much nailed it. I have a Megasquirt in my 5.7 and it's been pretty nice. It's very flexible, so you can start with just the basics and gradually add features as you get used to it. It's also incredibly capable, but requires a little more knowledge to get it to work. You can just about make it do anything, but you might have to build a circuit yourself to interface with the component you want.

I debated a FAST system as well, but ended up finding my Megasquirt for a good deal first. The FAST setup can actually run a port injected system as well as a throttle body injected setup. They don't advertise the port setup much, but it's basically the computer and a wiring harness. You'd still need a throttle body to replace the factory drive by wire setup, but you wouldn't have to change manifolds for a throttle body injector setup. It's also more of a closed system that only auto tunes as I understand it. That means you can still change engine parts and relearn, but you can't necessarily manually change something in the tune (I might be wrong on this).

The Holley I have no experience with, but I think is similar to a Megasquirt setup. I think it's a little more like a plug and play setup in that it probably has several canned settings that you can pick to match existing engine parts, but I've really never looked into it much. Frankly, Megasquirt setups have come a very long way and they have a nice plug and play 3G Hemi setup and some nice weather sealed units that can be mounted in the engine bays now, so I'm not sure where the Holley really fits in the equation other than name brand.
 
Depending on "what all" you are doing, you don't "need" the Holley dominator. The HP based ECU is no slouch. I cannot name them all off the top of my head, but some of Holley's "non mpfi" systems use the HP computer and can be upgraded. Only the name changes, ECU is same.

I THOUGHT I heard that Holley now has a plug/play hemi setup. Holley has a forum, and Denny is extremely helpful

A quick Google shows they do have some......

https://www.holley.com/news/articles/holley_releases_plug_and_play_efi_harnesses_for_gen_iii_hemis/
 
My project recently switched directions. I was going to convert my 408 to EFI with Megasquirt, buy I acquired a 5.7 so I'll be using this instead. The good thing is I can still use the MS3X controller with the 5.7.
If you don't want to build the controller or harness, check out efi source. They have a plug and play kit for G3 Hemis at a really good price. It even comes with a base tune.

http://www.efisource.com/shop/ms3-gen3-hemi-plug-play-gold-box/
 
I'm kinda leaning towards the megasquirt system has anyone used the drag pack intake on a stock motor? I like the idea of having an old school air cleaner sticking through the hood scoop and still having fuel injection
 
dartboy73 said:
I'm kinda leaning towards the megasquirt system has anyone used the drag pack intake on a stock motor? I like the idea of having an old school air cleaner sticking through the hood scoop and still having fuel injection
Click to expand...

I'm sure it would work. You just need to decide if you want to drop $1k on an intake. Ridiculous how much intakes cost for the gen3 hemi. It's no more aluminum than a POS 350 Chevy intake
 
I was leaning towards the Hotwire setup, but I reckon the EFI source kit is looking pretty attractive. Pretty much anything is going to run to about $2K give or take a few hundred, that seems to the market price.

Holley, good and bad is the modular harness, you basically need to buy 3 separate harnesses, main, coil and injector, more flexible I guess, but adds to the base cost. They also offer a drive by wire harness if you want to use that option.

EFI Source, base kit seems very complete, just need to convert to cable operated throttle body, not a bad choice if you are going to run an old school auto where you need the kickdown operational as that is one less thing you need to deal with.

Hotwire is good if you are running a stock 5.7, anything else you will need to buy one of the diablosport tuners, which all adds to the cost.
 
turbofreek said:
Holley hp efi. Forget all the rest with headaches.
Click to expand...

fast 2.0--any intake, cable operated, air filter in the hood scoop. self learning, also able to fine tune to your likeing. drawback- adapting from universal chevy layout on the wireing. pretty kick-a$$. ($$ literally) :coffee2:
 
I've been researching the controllers too. One of the most experienced and successful EFI tuners I've found said, " The Holley box is by far the best I've ever tried, and the self-learning function is so good it's almost like alien technology. I'll never use anything else again."

That is a pretty impressive testimonial from a guy who's been doing this for a living over the past 15+ years.
 
I'm consistently tempted to upgrade my Megasquirt setup with one of the MS3 Gold boxes that are prebuilt for a 3G Hemi, but I can't make myself spend money quite that easily. I just like the flexibility of being able to use just about anything you want with the Megasquirt setup, but it does take some dedication to make some of the parts work. A plug and play "black box" is nice in a certain sense because it's easy when it works, but if something goes wrong it could be harder to diagnose.
 
So if I went with the holly and decided to run a 545rfe how would I do that?
 
The only thing holley does that megasquirt doesn't do is closed loop WOT (including nitrous). Some argue it's a bad idea. Others swear by it, as it saved their motors in quarter mile passes when a fuel pump started to fail (multiple were boosted). MS3x stays open loop for WOT, and has AFR safety that you can enable and set the parameters- if the AFR's go outside of the window you set for that rpm, it will cut to a limp mode.

Fast, Holley, and MS3x all have very similar features. Factory computer has its own advantages, well really just one, being knock control (megasquirt has knock control as well, though I haven't decided to figure it out- it's not that simple)

My advice is this:
Use the system your tuner prefers. If you are going to tune it yourself, use megasquirt.

Footnote: I have a buddy who just swapped from FAST to MS3x on his 3G Hemi because he needed the diagnosing capabilities of MS3x. I'm sure he will sell the FAST. Rylispro on Moparts, maybe on here as well.
 
dartboy73 said:
So if I went with the holly and decided to run a 545rfe how would I do that?
Click to expand...

There are no aftermarket controllers for the 545rfe, if you want to run it as your OD you need a factory ECU I'm almost positive. Remember that the factory ECU can still be modded for cam, boost, or whatever with a piggyback controller.
 
I run the FAST on mine, I have about 1000 mi on it so far. FAST does "self tune" fuel, by adjusting the VE table to match the desired AFR that YOU CHOOSE for that point on the graph, so Dyno tuning or datalog tuning is still 100% necessary. It also does not tune spark, and cannot use the factory knock sensor. So spark tuning is up to the operator as well. I like the system, and have my car pretty dialed in at this point and am very happy. However the learning curve is steep initially. My Hemi kit came with NO base tune when purchased but I think they come with a generic program for the Hemi now.

Joe
 
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