craiger

If i change my ecm to the typhoon ecm, will i have problems if i run the car normally aspirated?

craiger

OK..I just purchased a 7749 ecm from a 91-93 Typhoon Now i need to get a chip for the ecm and the chip burning kit.

Grim Reaper

The SyTys used AXXA, AYBM, AYBN, BBZA and DOAC to name a few BCCs.

Run the BCC through this link http://holman.cs.uml.edu/~sdurphey/bccfind/ and they will give you a full description along with a part number.

Grumpy

No more so then tuning any other chip to work in your car.

Things will work, just in addition to changine the engine cylinder select you have all the tuning difference from between a v6 to v8

Be sure to use a v8 memcal

craiger

So what kind of memcal will i need?

craiger

And how do i set up the ecm for the difference of my 8 cylinder from the 6 cylinder it cam out of? 2 more fuel injectors...? and will the 7749 plug into my current wiring that plugs into my Z28 ecm?

craiger

So I need a V8 memcal? I guess that means that i can not use the memcal that came with the typhoon. I need more info on this since I was going to bid on a typhoon memcal on ebay.

Thank you guys for all of the help!

Craig

TRAXION

Wanted to make a quick post since I too have a 749 on the way ....

I have a 749 ECM on the way along with yet another 730 ECM and its harness connectors. I will be hacking up a 730 ECM to create an adapter that will allow me to EITHER adapt my 730 harness to the 749 ECM OR to adapt my 730 harness to work with a 730 ECM that is running $58 SyTy code. I have already created an Excel spreadsheet that does a full pin for pin comparison between both ECMs. This will be helpful in creating the adapter harness (or to just repin my own harness which I don't intend to do). There's really no point in hacking up a good wiring harness ... just create the adapter as per how Mike Davis did it. Both the SyTy wiring schematic and the 730 F-Body wiring schematic are located at the DIY FTP site. However, I believe that the SyTy schematic is incomplete as it is missing both the Fan Control pin and the EGR Diagnostic pin. Need to get a helms manual to prove I am correct.

Running the $58 code inside the 730 ECM allows you to still use the Atmel EEPROMS. Plus, the 730 ECMs are much easier to find. Running the $58 code inside the 749 gives you the piece of mind that the code is being run inside a box that GM designed it for (thx for the reminder on that one Bruce!). I intend to set mine up for both. I think there is only a 1-pin difference between running the $58 in the 730 on a 730 V8 TPI harness as compared to running the $58 code in the 749 on a 730 V8 TPI harness. In either case you have to repin several inputs and outputs. I am just thinking ahead in that if I create the adapter I will create it in such a manner that I could do either.

I won't be doing my conversion for a few months since my car is currently still 'under the knife' ... I am just in the process of collecting data since I really want to get the $58 code running inside a 730 ECM.

You need to use a V8 MemCal either way. Need the hardware to set properly via the NetRes.

Tim

craiger

So how in the HECK am i going to addapt my wiring harnes to the 7749 ECM? And do i just need any old v8 memcal? or should it be a Z28 memcal from a 91 Z..my car is a 91 Z28.?? Thanks again!!!!

AlexJH

Compare the two pinouts of the ECM's (I think you can find both on the DIY EFI ftp site), and put the wires where they need to go.

I think any memcal for a 90-92 with the same size engine will work.

craiger

THANK YOU!!!! valuable info!

SABLT194

Trax,

Keep plugging away on the 730 conversion. I have the perfect situation that will require this. Will be doing 455 olds w/ 8-71 blower and a 730 PCM. We just now have it running with no tuning yet. We'll start in to tuning this spring. Let's see you live in Fredrick MD , that's about 1 hour away. Interested in a field trip this spring to south central PA?

Your Tuning 101 is a wonderfull piece of work and I thank you very much.

Steve

TRAXION

Steve,

I'll get it worked out. It will just take awhile. I need to get my heap running first I always bite off more than I can chew once winter sets in. Hopefully I will have it running in June or so - lol.

Tim

anesthes

iTrader: (12)

I was wondering about the fan stuff my self.

The $58 DEF in TC shows cold fan enable, and hot fan enable.

Ok.. So when do the fans turn back OFF ?? wtf.

-- Joe

Grumpy

Look at the Sunbird diagram for the fan control.
In the Syclone's they run a CAC, which is the fan for the Air to water intercooler.

anesthes

iTrader: (12)

I c.. so it uses the same control leads? interesting..

-- Joe

Grumpy

The ecm Printed Circuit Boards are meant to be somewhat universal. So they can add, and move things around. Like the WB patch for 58 uses the TPS 2 input, as I recall. Also the 747 has an input for a MAF. There's some strange stuff floating around in GMWorld.

anesthes

iTrader: (12)

But as far as the code goes.. On a Sunbird it controls the coolant fan, on a Sy-ty it controls the intercooler fan ??

But both were based on coolant temperature?

-- Joe

Grumpy

Run in boost for a while and the CT does raise.
Gotta remember this is an oem appl., so they do play some games. ie the intercooler at times acts like an interheater. And you do want some heat in the charge temp..
Also, it's an truck/SUV which is a bit different then a passenger car.
GM has teams of really clever folks, and it's easy to misunderstand the logic in some of the stuff they do.

Least that's how I see it.

anesthes

iTrader: (12)

I understand. I kinda like the fan controls on $8d. On off for each fan, max mph for each fan, etc. but I'll eventually have to run $58.

When I put my car back together (new exhaust, rockers, and other things). I'm gonna do some running with $8D and 99% dc to see how the 02 readings go.. I can use that to better base my injector sizing. I'm guessing my bsfc is around .55 right now.


The problem with the calculators (off topic) is you can't really pinpoint the fuel requirements correctly. In Tim's setup for example, hes running a 30pph sv0 injector (which is what like 32-33pph?) at 77% dc @ 43psi and he's pushing around 475hp.. Running 11.60 e/t's

I'm running around 420hp with sv0-24 injectors at 91% dc @ 65PSI!!! and only running 12.60 e/t's..

Using the BSFC on Tim's data, it would suggest his BSFC is around .42.. Thats very very very low.. I know he's n/a, prolly has lower overall compression, and alum heads help -- but that much?

So it seems there is a million variables that effect injector sizing/bsfc..

On a side note, I was thinking of swapping to $58 before I go with the new injectors, and run a rail pressure of 65psi and get some scan data with that.. But I think the 65psi rail pressure might be too much for idle / part throttle stuff down below. What do you think??


-- Joe