Speed density

[badco]

So im deleting maf on my 96 when i go 0411 pcm. Seen when i searched on here that everyone saying would need two tunes. So how does a 93 lt1 run so good any time of the year? Even my 05 trailblazer is speed density and it runs all year the same. Just seeing why people are saying wont work right and why.

 

[Awest623]

It's mostly a function of the ECT vs IAT bias not being spot on.

If you're deleting your narrowbands then it'd be a good idea to have multiple tunes. If you're keeping them then you'll be fine. Ideally you can tune the ECT vs IAT bias to keep in dead on year-round. But the narrowbands will keep it inline.

Any reason to delete the MAF? It does help and it's always good to have backup sensors in case one craps out.

 

[Supercharged111]

I rode SD for a while in my 1500, even after the 411 swap. One day I hooked the MAF back up and the truck drove so much nicer. Why do you want to delete it? I'm supercharged and kept it and can't top it out down here in MI. I'm close, but think I have just enough room left to drop to a 1 5/8" pulley and still be OK without rescaling it.

 

[badco]

My old lt1 was a sd car factory and i really liked it over the 95 i had with maf, even my 05 trailblazer is sd factory and its smooth and nice.

Ive just never been a fan of maf.

 

[badco]

Im not worried about topping it out or anything, basically a stock engine. Same thing as my 68c10, its gonna be basically stock 5.3 but most likely it will be sd when im done.

 

[badco]

It's mostly a function of the ECT vs IAT bias not being spot on.

If you're deleting your narrowbands then it'd be a good idea to have multiple tunes. If you're keeping them then you'll be fine. Ideally you can tune the ECT vs IAT bias to keep in dead on year-round. But the narrowbands will keep it inline.

Any reason to delete the MAF? It does help and it's always good to have backup sensors in case one craps out.

So basically i was going to tune it like i did my 05 trailblazer, its speed density factory. I just log it driving and get timing where i want it. The ect and iat are not big factors on it as far as corrections, mostly map does all its work. Thought about using a map from a trailblazer so i know it will work

 

[L31MaxExpress]

Stick with the MAF. LS PCM runs alot better with the MAF than without it. My ~525 hp 383 is not even close to maxing it out. I have a 100mm MAF housing with a LS3/LS7 cartridge MAF and a 6:1 flow straightning screen. I have found the engine actually runs better with MAF only on the top-end. Measuring airflow is better than calculating it since the MAF sensor itself corrects itself for density and humidity. Blending SD and MAF seems to help the idle quality and lower rpm throttle transitions. I have run my engines on BOTH solely and they all run better with the blended values of well tuned tables.

My Nissans and Infinitis are MAF with factory widebands. Easiest vehicles ever to tune.

 

[L31MaxExpress]

For startup and break-in on my 383 I disabled the MAP blending, setup a conservative timing map, set the injector size, set the injector compensation values, and used the MAF values Lingenfelter supplies for their 100mm MAF. Engine fired right up and ran with almost perfect fuel trims and great driveability. I drove it for 2 weeks before I actually started fine tuning it. Fuel trims were between -2 and -8% and WOT AFR was 12:1.

 

[badco]

I guess i want speed density because i have tuned the older lt1s with it. On the nhra stock eliminators they all have speed density And we was getting 560+hp with stock lift, no porting, stock throttle body and intake. O and stock stroke, rod length and piston design. That was in 2005 with a pcm set up that looks like DOS compared to what available now being windows 10. Was a accel pcm and harness i think

 

[badco]

And without maf on my 96 i can do my snorkel type deal ive been thinking of. Playing in the creek and in mud isnt a stock airbox friendly deal.

On my c10 it just look cleaner under hood without it.