Tuning a 747 versus Megasquirt II for a new ground-up project
 

I used to hang out here a lot back when I converted my 86 Bird to TPI, so I'm slowly getting reacclimated with the technologies. My next project is taking all of the spare junk I have around to build a daily driver and get out of a car payment since I've had to take a pretty steep paycut to stay employed.

I've got a Holley Performance TBI unit 502-6, choice of Edelbrock performer manifold with adapter or factory intake bored to match the TBI, MSD coil and module, Mallory Hyfire ignition box, 180 T-stat all going on a 350 bored 020 with a mild Comp Cams High Energy cam (flat tappet) and 091 "camel hump" clone heads at 9.4:1 compression ratio. I'll have dual- exhaust with an H pipe, and a pair of baby cats and mufflers.

I'll more than likely be slipping this combo with a 700r4 on a 2wd S-10 frame, then finding a body to drop on it (pre-1996 due to PA Emissions regs). I'll need to source wiring and an ECM for the engine, which is why I am looking for the pros and cons of those who have worked with either the 747 or a TBI megasquirt. Thanks in advance.

Re: Tuning a 747 versus Megasquirt II for a new ground-up project
 

I am sure the MS is way more advanced that a 7747. 8746 offers IAT sensor. What is a TBI MS? I thought a MS are all the same just mod for the type of injection system you have(TBI vs MPFI vs sequential). I know there are older and newer versions. Like on ebay.

Re: Tuning a 747 versus Megasquirt II for a new ground-up project
 

I'm just looking for some opinions from guys who have played with both.

Re: Tuning a 747 versus Megasquirt II for a new ground-up project
 

I'm using MS-I with a modified 1985 Corvette TPI harness and intake. The harness for TPI or TBI is essentially the same, you just have to add extra injector bungs for MPFI from what I've understood. I started off with a MPFI harness so it wasn't an issue for me, but I'm told my harness would work as a straight carry over to a TBI system. I know MS-II allows a 12x12 VE table, full spark control, and IAC control, compatibility with GM flex fuel sensors, 21psi MAP sensor for boosted applications (upgradeable to 44psi), speed density or Alpha-N algorithms, as well as other goodies. Last I checked a fully assembled MS-II from DIYAutoTune was under $450. I've been running my MS-I since 2007, first on a stock 305 and now on a .040 over roller 327 with LT4 Hot Cam and modified GM Crate Motor heads, and it has yet to disappoint me in any way. As far as ability to tune, datalog, get real time data and make changes on the fly, and handle upgrades to the engine well beyond stock you simply can't beat Megasquirt, especially when it comes to price comparison with other aftermarket controllers. The only stock ECM I've heard of being remotely as handy are the LS ECMs, but that was up until the end of LSEdit's availability.

Re: Tuning a 747 versus Megasquirt II for a new ground-up project
 

Thanks Chimaera. I'd be looking at the MSII and going form there, although I did see in one of the stickies that there was a MAF conversion done for TBIs with a later TBI ECM... so much has changed since I was in the game 6 years ago! I still have my Pocket Programmer and UV eraser hooked up to my Pentium II machine with Windows95 :)

Re: Tuning a 747 versus Megasquirt II for a new ground-up project
 

Easy one,...the answer for using a good 'ole GM ECM, the MSII cannot compare.

http://www.dynamicefi.com/EBL_Flash.php