the Holley ECU is Just a far better controller than teh stock ECU....
its faster to take in data, faster to calculate what needs to happen, and faster to make the change as necessary...
the Holley uses a wideband to control AFR at ALL RPM's and ALL Throttle Positions..
the stock ECU does not... it uses a narrowband to control Fueling at part throttle and doesnt do any corrections at WOT(except for adding some fuel if it see's Positive LTFT's even though it has no idea if your upper rpms are right or not)


Just to name a Few that I use...

Extra benefits of the Holley over the stock pcm
better Rev Limiters and multiple Rev limiters (High RPM, 2 step, 3 step or burnout limiter)

4 stages of Nitrous plus a purge, all can be used Dry or wet, and can be Standard or Progressed, Timing can be removed by RPM, or by Length of Time.

Individual Cylinder Control for Fueling and Timing
High or Low impedance injectors
True Speed Density, or Alpha-N Fueling Control, or a blend of the 2(very useful with a BIG Camshaft)

All things the Stock PCM cannot do....well.. stock pcm has a really crappy Rev Limiter, and can use High Impedance Injectors...LOL

 

Thanks for the info. So I shouldn't waste time with buying and learn hp tuners then lol

 

If you are buying a Holley unit... then you wont need or be able to use HP Tuners with it.

 

I put a Holley HP on my built LS7 with a borrowed tune from Mas280 which was for a 440 resleeved LS2 running cathedral port TFS235's/FAST90 intake and different cam. It fires right up and does idle a bit rough when cold.... but once the coolant temps get up the WB02 starts making corrections and it is totally driveable and idles good and part throttle is good too. The more you drive it... the more it learns. You simply hook up your laptop and overwrite/update the existing base tune with what it has learned. Incredible system. No more paying local tuners $600 and being at their mercy for changes. I have a lot of learning to do with this system; however the self learn capabilities of it are impressive and got me on the road.

I also am horrible with electrical/wiring and this was a breeze with the LS specific engine harness. Literally all hooked up in a couple hours ready to fire up taking my time.

I sold my stock PCM and rewired/relabeled computer for $500. Saved $600 on getting it tuned. The Holley was only a few hundred bucks more and is waaaaaaay better. Also with my engine being modified the local tuners make it a speed density tune so it is a locked tune and won't compensate for temp/altitude etc. A locked tune is also not going to get anywhere near the fuel economy that the Holley can achieve which is important to me.

Traction control from Davis Technologies was just released www.moretraction.com as an additional module ($599/$999), they have progressive nitrous controls, 2 step, boost controller, serious data logging, meth controller, etc.

 

I just want to be able to tune my car. So was going to look into getting the software. But if the Holley system was better I would think about going that route

 

Megasquirt also has auto tune capability. If you are willing to do a bit of wiring between your stock harness and the megasquirt it can save a bunch of $$$$.

 

Yeah wirin doesn't scare me. I will look into it also

 

Theres a reason its more budget and does not cost more than it currently does....
its OK... but not near as good as going with a FAST XFI or a Holley EFI system

 

Plz define "Good". Do you mean capable?

Just IMO, same as yours.

I have had much success with MS2 on several of my swaps. I have used HP Tuners over the past 9 years, Tunercat for OBD1 and Tunercat for OBD2 and use them regularly tuning several cars per week.

Most customers dont need the many extras that more expensive models offer like sequential injection and individual cylinder timing adjustments. I have used plenty of aftermarket systems and like MS. Being able to gra the 3d fuel and timing map values and have it immediately affest the engien is great feature. It takes about a 1/4 second to update the PCM while the engine is running. MS2 offers step rev limiters, NOS conrol, Real time tuning, free software, future hardware expandability. Just needs a bit of configuring just like other systems to set up. I compared the MS software to BS3 and it is far superior far as user friendlyness.

I have another Microsquirt system being shipped to me and will do a tutorial text and video of how to set it up on a LS1 soon as it arrives. Just never got around to making a good video on the other installs.

Here is a sample of some projects I have wired and tuned:

http://s704.beta.photobucket.com/use...27540753745104

Also, I have had several friends that have had to send the Holley system back for reairs as the autotuning did not function in their cases. Commercial ECU's are not 'repairable' and if they fail and all electronics will fail, you are stuck with a brick.

Just letting you know there are options out there that are affordable for the DIY kind of guy.

Well, good luck with your PCM tuning buying decision.

Just IMO, GBU and GBA

 

Holley 550-400. I purchased this unit with the intent of just doing the Holley EFI on my 78 vette with SBC and auto trans. Big ideas and now going with LS swap and purchased a LQ9. Are there going to be changes to engine harness in the kit for this to work for my set up?

 

I want to make sure it's made clear that the Holley will tune the fuel table but does not "self tune" like I have heard many say on other forums and threads. The Holley is a nice system but can't replace the knowledge of a good tuner.

 

Looks like these to harnesses will get my going.
http://www.holley.com/558-102.asp
http://www.holley.com/558-201.asp
Since I haven't done the fuel pump conversion yet will the Fuel pump that came in my kit work for the LS Swap.

 

correct......it does not self tune... it only self corrects to the Fueling you put in the desired AFR table...
with an LS Motor, you can use their LS file and its close enough to be safe


we should actually say that it "Self Corrects" to the tune you put in it.
and it does a very good job at it, much better than the stock pcm

it is still up to the end user to "tune" the vehicle

No systems currently "self tune" if you want to take it to the point of the pcm doing the tuning

 

subscribing !
and thankd for the writeup!

 

guys really appreciate the dialogue here. installing an LS based engine and i need to decide on ECU and harness so i'm sitting and listening.....subscribed!

 

I have not seen this question come up or answered yet on any forum.

Holley HP is a single o2 sensor.
Which header did you install the sensor in?
Is there a leaner side of the LS motor?

 

depends on your setup...
honestly..do a test.... put it in one header... let it get close
switch it to the other and double check

typically, if you are using the stock rails, the passenger side will be slightly leaner(it sees less pressure because fuel hits the injectors sooner on the drivers side)

if you use a system that has a regulator after the rails, and you go into the first and out to the second then out to the regulator, it will be leanest on the 2nd rail in the chain

if you use a Y and hit each rail at the same time, then its going to be pretty even but more dependent on your engine...and then, its usually close enough that you wont be able to tell from trial and error back and forth... you need 2 you can look at at the same time.

 

ok cool. I have a stock rail setup for now. Headers just came in today

Thanks

 

Im going to run the dominator unit. Im turbo'd though. I was going to run 2 O2's but they say no to put before the turbo. They said to put them at least 20 inches from the turbo. I would much rather monitor both side but the back pressure messes with the reading. What do you think?

 

the only thing iv heard about it i dont like is that you cant use the factory gauge cluster. can anybody verify this?