454SS tuning

[Fast355]

Something does not seem right with those desktop dyno numbers! I had a mild 8.9:1 350 with ported vortecs, single plane intake, and long tubes that made 360+ RWHP. If that engine is not 425 HP to the crankshaft, I would be very suprised.

[EagleMark]

Well if you enter same data in DD2000 and DD2003 you get a 100 HP difference?

[1BadAction]

I thought the 454 SS started in 91 with the 4L80E? So what ECM and tranny did the 90 have?

There's no injector settings in this PCM, instead it starts with a BPC/BPW. It's all in the calculator spreadsheet I attached earlier. Let us know if you need help with it?

1990 was the popular year. Turbo 400 trans. 91-93 they didn't make many at all.

[Fast355]

Well if you enter same data in DD2000 and DD2003 you get a 100 HP difference?

Try inputing duration at .004 or .006 and see if that levels the playing field some.

[Nasty-Z]

I thought the 454 SS started in 91 with the 4L80E?

It did

So what ECM and tranny did the 90 have?

90 had the TH400 with the '8747 ECM , 91-93 had the 4L80E with the '7060

TOM

[Hog]

It did



90 had the TH400 with the '8747 ECM , 91-93 had the 4L80E with the '7060

TOM

1990 thm-3l80/400, 3.73 14 bolt 9.5" SF 230hp @ 3600rpm/386 lb/ft torque.@ 1600rpm
91-93 thm-4l80e, 4.10 gears 9.5" SF 255hp @ 4000rpm and 405lb/ft torque @ 2400rpm lb/ft torque

13,748 were built in 1990 alone with a total of 16,953 trucks built from 90-93 leaving 3,205 produced for the last 3 years of production 91(983),92(1,379),93(843). This is why you mostly see the black/red colour combo for sale. Not many 91-93's for sale.
This sales trend was also seen with the 1990-1995 Zr-1 Vette with the 375-405hp LT5 DOHC engine, many built for its 1st year, then trailed off for the 2nd and remaining years. LT5 production was finished in 1993 and the engine were put into storage for the 1993,94,95 model run.


peace
Hog

[mixbox]

Im back, i have the car running with the new parts. I ran the car on idle for a while and logged it. I dont really know what to look for hehe.

[mixbox]

Noticed that i had a code 42. Connected the cable on the firewall.

This log is with the cable connected. It runs a bit rough..

It wont enter closed loop. I tried finding the settings for entering closed loop idle as 1BadAction suggested " set the "rpm to enter closed loop" to 25 and the "RPM to exit closed loop" at 50, this will allow closed loop idle." But all i can find is "RPM to enter Open Loop" and "RPM to exit Open Loop"

[EagleMark]

Try revving engine or if driveable go for a short drive along with idle data. Sometimes the O2 is just not hot enough? Data says it's not ready and engine temp was close to 200*f... should be ready!

[EagleMark]

The error 42 is still present but looks like timing is working. Have to clear codes!

[mixbox]

Did my first logging while driving yesterday. Adjusted the timing that was a bit off (set to 0 when i did this run)

[EagleMark]

Need to split up logs, that one is way to big and it died about 1/3 way through.

But what I saw was typical for a cam change. Low BLM numbers at low MAP where it needs less fuel and high BLM numbers for higher MAP where it needs more fuel.

Probably need a little more timing throughout, even more at idle and raise idle a little.

You have to clear codes every time you set timing or the error 42 is present.

Hope some of the other $85 guys jump in to help, I'm going to be out of commission for next couple months.

[mixbox]

Ok file to big. I will have to separate them from now on..

Maybe i set the timing back to much..

One thing i don't get is why is there only one VE table? What happens after 4800rpm?

[billygraves]

Ok file to big. I will have to separate them from now on..

Maybe i set the timing back to much..

One thing i don't get is why is there only one VE table? What happens after 4800rpm?

Code 42, EST, is a "Latching" Diagnostic Code. Functions like this: Ignition cycle 1 you set the base ignition timing, reconnect the tan By-Pass wire and key off. The ECM will shut down after 10 to 15 seconds or "Go to Sleep" post key down. The next Ignition cycle the Diagnostic Code can be cleared from memory IF no new Code 42 appears.

[EagleMark]

Maybe i set the timing back to much..

One thing i don't get is why is there only one VE table? What happens after 4800rpm?

Pretty sure base timing is 4*.

After 4800 it runs the last cell it was in.