I am planning to add a mild SC to my Vette and expect approx 375-400hp (flywheel) I notice searching though old post that every post pretty much say the 165 and SC are a bad combo. (I know about 749's as I have some experience with them.) I am not going to be too far past 255 g/s limit, so I don't think their will be too much an issue of fueling it with PE?

I would prefer to keep the 165, for resale value and simplicity.
Are their other factors, that I am missing? Are the VE of over 100% going to really going screw up my part throttle tuning?

 

As you noted, adding the extra fuel via PE is fine for WOT. Get a W/B sensor and you can do a reasonably good job (though it is still not the best solution).

But the real problem is part throttle when you get some "boost" that causes VE to exceed 100%. The only two solutions I have found are: 1) add a signifiacnt amount of fuel when the MAF approaches 255 and 2) do a lot of monitoring and data capturing to determine at what part throttle/rpm/ you seem to max the MAF due to boost from the SC. Then modify the WOT PE Tables to start adding fuel at those throttle/rpm levels.

As you can see, nothing is anywhere near to the proper solution. And none will give you a "proper tune" for fuel as you will end up with "one setting for all instances of the MAF being exceeded". It is much easier to "kludge" a naturally aspirated MAF car that maxes the MAF than a SC MAF car. Typically, MAF guys will use some form of a "fuel adder" managment system for this very reason.

 

Us maf guys.. err. wait, I converted oh yeah.

Anyway, You'll want to get a FMU and some sort of timing retardation device.

Then spend some time in the chip. get frustrated, and switch.

The 165 has lots of silly issues. Good luck.

btw.. Repinning to 730 (with the correct tool) took me 1 hour. this includes labeling everything. And the under the hood (short two wires, wire map into 3 of the maf wires) was another 15 minutes.
The hardest part was finding a vac line for the map..

Lets cost it out:

730 ECM - 35.00
730 memcal for v8 - 40.00
Adapter from moates, cuz I SUCK at soldering - 45.00
Tool to repin harness - 5.00
Map sensor - free, had a few

$125.00..

You can wait for one of us to really start hacking 730, OR goto 749
either way with 20 minutes of repin, and a 2-baro map upgrade.

-- Joe

 

Ding, Ding, Ding, Ding!.

All the MAF tables assume a relatively linear, commanded AFR.
While you might have 120 gms/sec at 4K RPM, the engine will be in a mid throttle position, and yet that 120 if it accures at 2K rpm would mean the engine is in boost, and needs a whole lot richer of AFR. At 4K 13:1 would probably be fine, yet if at 2K you'd want at least 12.5 and maybe as much at 11.8. 13 to 11.8 is a HUGE difference.

If you look at the calibration for most MAF systems, you'll see they go into a form of Aplha-N fueling. Thou based on the MAF being pegged, the final AFR is % change, at various RPM steps.

FWIW, a street engine will MAY run as high as 85% VE, in a turbo application 120 is no big deal and 150s can be reached.
Alan Lockheed has mentioned these number in his various works, software, and seminars.

Gee, we just need someone think thou the Limits of the MAF itself, and see what can be done to work around them. <g>

If you want to run a MAF and a Turbo, S/C you might consider boost refering. I posted about that at the GNTtype list.