How far does the SD ECU have tables to? Like the LT1 ECU only has tables to 7000 rpm and if you want to rev past that then you need FAST or some kind of DFI.

Thanks
Jeremy

 

7730, 7749 = 4800 RPM in the tables.

As far as timing, you won't need any higher really. Most people have timing in by 3k-3200..

Tuning fuel after 4800 is a different story though..

But there are all kinds of tricks around that..

-- Joe

 

Was wondering bcuz the guy who built the 380rwhp and 420rwft motor that was tuned by Ed Wright, HITHERE think he reved that motor, on the dyno, to 7200rpm or so. Does the software to burn new chips let you add tables so you can rev higher? Could HITHERE use the stock SD computer on HITHERE 8000 rpm solid roller motor? HITHERE guess my real question is how high can you go with the stock computer and burning your own chips?

 

Actually, the Extended Spark Table on a 7730 can support spark advance tuning 5,600+ rpm and the PE Fuel Table supports fuel changes to 6,400+ rpm.

As mentioned above, generally most of the spark advance should be dialed in by 3,200-3,600 rpm so the spark tables are overkill. As for the fuel, you cannot modify the fuel trim any more beyond 6,400 rpm, that generally isn't much of a problem either unless your peak torque (max VE) extends beyond 6,400 rpm. For most engines (where peak torque does not exceed 6,400 rpm), you'll tend to run richer than needed.

If you REALLY need to have additional fuel tuning capabilty, you can modify the code. There may even be a "patch" available (a patch to extend the spark and fuel tables exist for 7747 used in trucks, but they only have 3,200 rpm limits in their tables). But I have yet to see anyone running a 7730 that REALLY needs fuel trim beyond 6,400 rpm.

 

I didn't notice the extended tables until I loaded into TC.. I had been using gmpcm for the SD stuff cuz I was too lazy to download the new $58 and $8D defs for TC. My bad.

-- Joe

 

No need for apologies - it's really easy to forget or miss the extended tables. As I said, your comment about 3,000- 3,600 rpms for spark is quite valid. The extra "tunabiilty" isn't really needed, but it nice to have if you get into a "power adder" when you are into boost.

What's more important is that the $8D has plenty of "wide open spaces" and those fuel and spark tables can easily be extended if you find the 5,600+ for spark and 6,400+ for fuel a limitation.