7747-7427 Swap

PlayingWithTBI said:

Hey, @Scooterwrench send me a PM here, if you want. Maybe we can figure it out.

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I think I got it,just call me **** for brains!!!!

Explain ckecksums in caveman terms.

Well getting closer to doing this swap and start tuning. My PCM is over on the extreme right side,behind the glovebox. There is not a lot of extra wire to have the PCM hanging out so I thought to myself "I need easier access to the EEPROM. I came up with this remote chip holder so all I have to do is open the glovebox flip the ZIF socket handle up,pop the chip out and replace it with the already burned chip with the changes I want to make and lower the handle to lock the chip in. 10sec chip changes!
I bought the memcal adapter from Red Devil River and popped it in and the other parts from various other suppliers.

Getting the glovebox liner back in with that box header sticking out the right side was a little tricky and it doesn't have the ribbon cable and connector yet. I think when it comes time to do the actual installation I will probably have to remove the glovebox door. I should have hung it on the back wall of the liner but was worried the A/C duct would keep the liner from going all the way in and I was trying to keep the cable as short as possible.

OK,got a ? for anybody that has burnt chips before. I made an adapter to read the original 7427 prom and all the data was at the in the bottom region of the prom. I changed a few things like injector flow,TCC lockup and spark timing and burnt the new prom. I'm using the 27FS512 EEPROM and according to T-pro the data should be loaded starting from 000000-00FFFF but that puts the data in the top region of the prom. Will it matter? Will the processor be able to read it correctly?

OK,I'm planning ahead for probable tranny failure and after studying the mask for this 7427 I'm kinda leaning towards installing a 4l60-E it it's place when the time comes. The ability of changing shift points and shift feel intrigues me.
I've scored a factory wiring harness to be tied in when the time comes to run it. In this conversion for 700R4 one of the flags to set is "VSS not from DRAC" as there is no 40PPR signal to pin F12. When I install the 4L60-E can I use this same setting or will I have to run that 40PPR signal wire?
What about ISS? Wire it like the early 60-E's with no ISS?

Been working up a .bin for the 7427 with the 305 and 700R4 using the Fast 355 $0D 700R4 XDF. So far all I've changed is created EGR delete(on at 255mph and unchecked the flag), speed cut off to 255 MPH, RPM cutoff to 6200, changed PE delay from 15sec to 1sec, lowered WOT PE delay to 3000 RPM, changed TCC to lock at 40 MPH and unlock at 38 MPH with A/C on or off. I've added 2deg of timing across the board. I bought a WBO2 so I've set up the .bin to read that but will shutting off the EGR mess that up?
For fueling all I've changed is the cyl. volume. Not sure what to do with the injector flow. Do I need to compensate for added fuel pressure?,seems I would. I've not messed with VE tables yet until I datalog and see what it's going to do. Not messed with any of the IAC parameters either,again got to see what it's gonna do.
Anybody(tuners)got any suggestions for the initial setup?

Scooterwrench said:

OK,got a ? for anybody that has burnt chips before. I made an adapter to read the original 7427 prom and all the data was at the in the bottom region of the prom. I changed a few things like injector flow,TCC lockup and spark timing and burnt the new prom. I'm using the 27FS512 EEPROM and according to T-pro the data should be loaded starting from 000000-00FFFF but that puts the data in the top region of the prom. Will it matter? Will the processor be able to read it correctly?

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Oh yeah, I figured that out too. The .bin starts at address 00004000 on the original factory PROM.

Scooterwrench said:

Not sure what to do with the injector flow. Do I need to compensate for added fuel pressure?,seems I would. I've not messed with VE tables yet until I datalog and see what it's going to do

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Just set your pressure a little higher than stock, leave the VE tables alone until you can run some logs. If your higher MAP and RPMs run out of fuel on the WBO2, add some more pressure until that's good. Then worry about fine tuning.

Scooterwrench said:

I bought a WBO2 so I've set up the .bin to read that but will shutting off the EGR mess that up?

Click to expand...

I don't think so since your mask is reading directly from the sensors then interpolating them based on the .bin but, the data is always there.

At least this is the way I see this stuff, maybe @L31MaxExpress will have something to add or change...