Interested in Holley TBI 4-bbl Conversions to MS1 or GM ECM

[candu.sno]

Hi,


Joined this group after finding a very interesting EFI pump modification how-to (thanks Gregs78Cam!). Taking some time to search Forum topics for info.

I'm on the fence about which controller to use, having an MS1 version 2.2 and several '747 ECMs available. My traditional Pontiac engine will use a modified small-body distributor with 7-pin HEI module, VR trigger and locked curve. I am satisfied to use TBI based on previous OEM units but would like a 4-injector unit so I have some Holleys from dead-ECM systems. I hear the MoPar style early injectors can be trouble...

Mark
(candu.sno)

[dave w]

Have you looked at Dynamic EFI? Here's a link on injector driving you might find helpful: http://www.dynamicefi.com/InjectorDriving.php

The EBL Flash system is a very good option to consider: http://www.dynamicefi.com/EBL_Flash.php

dave w

[candu.sno]

Have you looked at Dynamic EFI? Here's a link on injector driving you might find helpful: http://www.dynamicefi.com/InjectorDriving.php

The EBL Flash system is a very good option to consider: http://www.dynamicefi.com/EBL_Flash.php

dave w

Thanks for the links. I have seen some info about extra drivers or resistors needed with two more low impedance injectors to run. My basic plan for the mechanical side of the install is sorted but whether to use the GM ECM (or modifed ECM from Dynamic) or the older Megasquirt to run the system is very undecided. The price advantage of already owning the MS1 and '747 ECMs is strong. I see a steep learning curve ahead in any case.

Thanks,

Mark

[myburb]

I have used ms2 and gm 7060 and 7427. I have them both on my burb and can switch fuel back and forth. I found MS code fueled quite nice but lacked any idle control. MSextra had better idle control but I didn't like the way it fueled but used it more than the 7060. Once I switched to 7427 I pretty well don't use MS any more. I personally feel the gm is more robust and reliable and parts can be easily found as long as you carry your bin file with you.

[candu.sno]

I have used ms2 and gm 7060 and 7427. I have them both on my burb and can switch fuel back and forth. I found MS code fueled quite nice but lacked any idle control. MSextra had better idle control but I didn't like the way it fueled but used it more than the 7060. Once I switched to 7427 I pretty well don't use MS any more. I personally feel the gm is more robust and reliable and parts can be easily found as long as you carry your bin file with you.

Thanks "myburb" for providing some actual experience with both items, I was thinking of upgrading to MS2 for real IAC idle control but perhaps my money is better spent on upgrading a GM ECM.

Mark