400hp magnum on DPI

[J-man]

First off sorry to the mods if I posted this in the wrong section.

So I have done a lot of research into engines lately but didn't come across a build looking to get the power I am seeking on port injection, the original game plan was to put a 400hp LA 360 in the 360 dart and later down the road upgrade to the Edelbrock DPI manifold and EFI setup.

The other day my buddy brought up the fact that if I want port injection I should consider a magnum swap because there was already a motor designed with that in mind instead of paying through the @$$ for one manifold. I have no issues going this route (just eventually sell the LA in the dodge) it makes more since especially with all of the advantages of the magnum motor roller lifters, rockers, higher comp pistons, and a new set of eddy heads (was going to do anyway).

So down to the meat and potatoes of this I will be running a manual in the car and want to achieve a 400-450hp mark on port injection. What all boxes and harness do I need to save from the donor vehicle? Or will the stock units not be able to handle the cam profile and other things I will be putting into the engine and I should consider aftermarket ECU like mega-squirt?

 

[jbc426]

For less than $1500, you can have a complete Hotwire Auto "Hotrod" wiring harness, a rebuilt ECU for a manual transmission car without the security function and a handheld programmer loaded with a couple of custom tunes designed for your combination. If you add a wideband, the tunes will be dialed in to optimize your A/F ratio's in real time. It's as plug-and-play as it gets and comes complete with factory reliability.

I have this set-up on my 408" Magnum, and I love it. All the sensors are factory, but I did spring for bigger injectors. My cam choice did result in lower vacuum, but the reflash took care of that issue.

 

[67Dart273]

For less than $1500, you can have a complete Hotwire Auto "Hotrod" wiring harness, a rebuilt ECU for a manual transmission car without the security function and a handheld programmer loaded with a couple of custom tunes designed for your combination. If you add a wideband, the tunes will be dialed in to optimize your A/F ratio's in real time. It's as plug-and-play as it gets and comes complete with factory reliability.

I have this set-up on my 408" Magnum, and I love it. All the sensors are factory, but I did spring for bigger injectors. My cam choice did result in lower vacuum, but the reflash took care of that issue.

For that kind of money, you can come VERY close to using a mag engine / intake, buy a Holley HP ECU and harness, and piece the rest you need, sensors, etc. The HP system is completely configurable in a way the stock ECU will never be.

I've been thinking more and more about playing with a Megasquirt. For the record (if I live long enough to get it together again) mine is currently a Holley TBI with an HP ECU

 

[jbc426]

Can you please elaborate on the various aspects of what is configurable on the Holley ECU, and how a novice EFI tuner would know how to take advantage of this configurability?
Also, do you use a laptop to change the configuration?

The reason I went with this factory ECU based set-up is it is quick and easy, it's plug-and-play and the performance difference is amazing between the factory tune and the custom tunes. I just plugged my tuner into the OBDII port, reflash a new tune into the factory ECU and it runs great.

To fully optimize the tune a wideband is hooked up, I shoot a video of the wideband readout while driving the car, send the video to the tuner via email, and he makes some adjustments and emails me back a fresh tune that I download into the handheld tuner. If necessary, this process is repeated until it is optimized.

This was the least expensive EFI solution without compromising performance and tunability. I ran this same system on a bone stock 5.9 and reflashed it to run my ported aluminum headed 408" stroker motor with a much bigger cam and injectors. I didn't have to struggle with the learning curve for tweaking Holley's fuel and ignition maps, and who knows what else. I know some guys like the process of trying to figure this all out, but I simply don't have the time or the desire to get that far down in the weeds with it.

I seriously doubt there is any performance gain to be had from my current configuration, but what do I know. I'm not trying to shave tenths of my quarter mile times or anything. It's just sounds like more work to me. Another upside is I can get off the shelf parts for my system anywhere in the US.

 

[67Dart273]

The best thing to learn the Holley systems is to go to their website, and forum. There are several Holley systems, all using the same HP computer. The only computer that is different (in current systems) is the Dominator, which is more capable yet.

There are several harnesses you can buy. I BELIEVE there is plug and play stuff now for the hemi's but I don't pay attention. You can also get a "raw" harness and interface your own.

"In short" the Holley system uses mostly GM based sensors, but are proprietary for some. They claim their O2 sensors are "special."

Things the Holley system gives you that OEM does not is stuff like logging, full configurability, you can use TBI, multiport, bank fired, sequential, and there are outputs to control "other things." My understanding is that the Dominator will control electronic transmissions but the HP won't. Again I'd go "over to Holley" and read up. Also, you can download the Holley software free and play with it some, to get an idea. Holley comes with sample maps and IS "self learning."

The big downside to me with Holley is that the ECU is sealed, but then, so is OEM.

Also, Holley makes some different displays which can be used, or a laptop. Their new "in between" display (about 200 bucks I think) will pretty much fully program the system with no laptop, as well as display various data and gauges.

AGAIN the best way to check this out is right at Holley and their forum.