Magnum swap-what all mods can you make still using factory efi

[lee g]

I am trying to find out what all mods/performance improvements can be made to the magnum motor and still retain factory efi. So far I have found the edelbrock/hughes intake, different heads such as EQ, but my concern is once you start going to a more aggressive camshaft (not a particular camshaft in mind) will the factory computer compensate for it? Can these be reflashed or a tuner used? Just wondering how much flexibility is there to retain the factory efi.
I have looked on this site as well as a bunch of the dakota sites as well but I didn't really see the answer to the mods I am looking at.

 

[67Dart273]

I've never seen a comprehensive "do it" website or anything else on reprogramming Mopar ECU's. It's always "send off" to him or her and they can reflash it. Ma seems to be the worst, as far as getting into, hacking, reprogramming their ECU

Frankly, I'd learn how to............. Megasquirt, go over to Binder Planet and learn how to adapt a GM ECU, or put a Holley or other ECU into your hardware. It will take some work. When you are done, you won't have to worry about engine mods, because then you can program the thing.

 

[lee g]

It seems that the mega squirt is a great option and that may have to be the route I go. I'd love to be able to stick with ma mopar products if possible.

 

[UOP]

SCT tuner with the stock ECU. I run around with a bunch of Dakota guys and that's what they run. Three of them are running 408 strokers with big cams with no problems getting a good tune. Check out the Dakota R/T forum, lots of good info there on this subject.

 

[jbc426]

SCT tuner with the stock ECU. I run around with a bunch of Dakota guys and that's what they run. Three of them are running 408 strokers with big cams with no problems getting a good tune. Check out the Dakota R/T forum, lots of good info there on this subject.

Exactly! Sean or Hemi Fever is an expert tuner with thousands of tunes under his belt. If you have a wide band and a video camera it makes it easier for him to see exactly what each tune is doing as it goes through the gears. Then he can dial in your tune even bettter, email it to you to down load into your SCT tuner and you plug it into your OBDII port.

The low vacuum signal the bigger cams have is the issue with a non-reflashed ECM. Once compensated for, they run excellent.

I used the ECM out of a 1998 Dodge 1500 with a 5 speed, as I have a non-computerized transmission. I bought it from Solo Electronics out of Florida. They disabled the security key fob chip and a few other things too. It has a lifetime warranty. It's helpful if you can beg, borrow or buy a real scanner, like Matco, Snap-on or one of the real dealership quality ones to troubleshoot any problems, set otherwise unadjustable settings and data-log cartain things.

 

[lee g]

Thanks. I will look more into the Dakota forums. Thanks for the info

 

[dartfever]

The factory EFI does not like a narrow lobe separation on the cam.
I have a 97 Dakota 318 with the following mods running on a hypertech tuner
Cam 260/264 114 lobe separation .487" lift intake . 496" exhaust with 1.7 roller rockers
M1 intake
ported stock TB
ported stock heads @.500" lift 243 intake 180 exhaust
edelbrock shorty headers
flowmaster catback

This combo was good for 247rwhp/265 rwtq with no loss of drivability or fuel mileage (to my amazement!)

 

[lee g]

Thanks for the reply. I have gathered some information now so now comes the hard part of saving up the money to start another project

 

[jbc426]

The factory EFI does not like a narrow lobe separation on the cam.
I have a 97 Dakota 318 with the following mods running on a hypertech tuner
Cam 260/264 114 lobe separation .487" lift intake . 496" exhaust with 1.7 roller rockers
M1 intake
ported stock TB
ported stock heads @.500" lift 243 intake 180 exhaust
edelbrock shorty headers
flowmaster catback

This combo was good for 247rwhp/265 rwtq with no loss of drivability or fuel mileage (to my amazement!)

The Hypertech Tuner and M1 intake are likely giving up a lot of torque and horsepower with this combo. What's the duration of the cam at .050?

 

[dartfever]

I know the hypertech leaves some on the table, but I can't complain about the torque. First gear is useless if you hop on it from a standstill. It is just a 318 after all. I have the mpi intake like the one in the pic. The cam is the original R/T cam MP offered. The .050 specs are 204/208. I tried a MP PCM from a 360 ram that worked extremely well but the gauges would not work.

Had a buddy run his 318 with the same cam, but with the original beerbarrel intake. He was 30 hp less but about the same increase on the tq side of things. To be expected I suppose.