2000 silverado 370 swap

My brother has a silverado we just finished doing a swap into. It was a stock 5.3 and now we put a 6.0 bored to a 370. Mods it has are forged flat top pistons, afr port and polished heads, tsunami cam 235/240, pacesetter longtube headers, stock intake and injectors, and its on stock torque converter and trans.

We are going to get it tuned by a professional tuner but for now we need it running to go get the exhaust done. I know its gonna be tough with stock stall because its such a high cam.

I did some minor adjustments to make sure it starts right up and doesnt stall, and now idles pretty good. Only thing is its stalls as soon as it goes in gear, and i know its because of the converter. Any way i cam get it to not stall when going into gear?

Another question i had was if i should change the ecm from 5.3 to 6.0? And change the cylinder volume too. I changed it on a seperate file and it change all my ve tables and other tables. Should i start over with stock 6.0 tables after making the change?

Thanks in advance

Yes, you need to change the cylinder volume to match what size motor you are running.

Stock 2000 truck injectors will be maxxed rather quick on that setup too, just a warning.

Raise the idle higher can help with the stalling, it's to say exactly what to do because so much is now going to be off. The base running airflow, the VE table and MAF curve as way off now because of the mods and those are the places you'd want to address first.

Ok ill start over with a stock 6.0 file, and go from there. I thought the injectors would be maxed out on this setup. We have a fast intake with 60 lbs injectors. Reason we did not install it was because 2 injectors got misplaced so need to order them and we need an after market throttle. And we are also changing the torque converter and rebuilding the trans, but installed the engine to break it in.

So far i have brought rpm upto 900 and base airflow up by 3 g/s. Made some changes to the ve table below 1200rpm to keep it idling a little better. Just the transition from park to reverse or drive instantly kills the engine. I was reading it needs more air when in gear because of the torque converter.

Stock intake will be better on this setup anyway in my eyes. FAST intake don't give you enough power gain for what they cost, they are also prone to leaking and having vacuum leaks.

I had heard bad things about them too, but will give it a try. I have so many different manifolds to try lol.

Btw im checking out a stock 6.0 file and many i have checked have a different firing order as the 5.3
I thought all ls engines had the same firing order?

So our truck has been running fairly well since i last changed the tune. I installed a wideband on it now along with a cai and full 3 inch dual exhaust with an x pipe. The problem now is it is very lean, reading 18:1 on hpt it even backfires on almost half throttle. I tried bringing up the ve tables by 20% and nothing even went as far as to increase another 20% and still marks the same. Tried messing with the open loop table as well and nothing.

Any help?

Will the stock fuel pump support all of this? Didn't see if it had been changed or not.

Post the tune if you want some help.

How are you currently trying to tune it?

Are you tuning in speed density only or MAF tuning?

here is the tune i have. i just started MAF tuning but still very lean. Any correctons done dont seem to affect it. Also put it in speed density and the truck was super rich, but would not idle at all even after many corrections. i am using a wideband to tune.

ill post the MAF after i try a few more corrections.

Quote:

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Originally Posted by Xeen1901

Will the stock fuel pump support all of this? Didn't see if it had been changed or not.

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I'm not sure. I think stock fuel pump should work but i could be wrong.

Are you setting the MAF fail high to 0hz and the 3 MAF dtc's to fail on first error when speed density tuning?

Overall is just looks like you only hit it with 20% and do no real data logging to tune it in. If using a wideband and an AFR error it should be pretty straight forward for making the changes. Then you can put in in MAF only and start tuning the MAF curve the same way with an AFR error.

The stock fuel pump might be enought for sure those small 24lb/hr injectors are not big enough for a 370 cubic inch motor. You'll max those out on your first WOT pull.

Quote:

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Originally Posted by 5FDP

Are you setting the MAF fail high to 0hz and the 3 MAF dtc's to fail on first error when speed density tuning?

Overall is just looks like you only hit it with 20% and do no real data logging to tune it in. If using a wideband and an AFR error it should be pretty straight forward for making the changes. Then you can put in in MAF only and start tuning the MAF curve the same way with an AFR error.

The stock fuel pump might be enought for sure those small 24lb/hr injectors are not big enough for a 370 cubic inch motor. You'll max those out on your first WOT pull.

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I only unplugged the MAF and set the dtc to first error. I got into speed density but could hold an idle. After about 4 corrections it was doing the same. I deleted the other tunes after this one because i was not getting any results. I started over but this time with MAF first. I started using the LTFT and STFT instead of the AFR Error and seems to be working. But wideband is reading lean and the truck is idling better and has no more backfires like it did before. In thinking maybe the wideband is not reading properly. I plugged it in my other car and it reads good. Might be the sensor or the a bad ground.

Gonna drive around and datalog, then ill post the tune and log for you guys.

Do you have a seperate IAT sensor when you unplug the MAF because if you don't the IAT temp will read -40 and screw everything up.

Oooh thats right. I thought the MAP would read iat. So far i have the truck running alot better at cruising speeds. I think ill leave it MAF only for now. Half throttle has it begging for more fuel and i think thats because of the stock injectors.

Only thing now is it might have a little too much timing. It sputters when very little throttle is given and afr seems fine at the time of it sputtering. Timing tables are stock except for 1200 and below, which i added timing for the cam. Will look into that next.

Ill post a tune of my progress as soon as i get to my computer, and a log or two for review and see if you guys can help identify the sputtering.

here are 2 tunes after correcting the MAF a few times. and the log files to go with them.

I can smell raw fuel frm the exhaust but wideband is reading 18:1 afr on idle..

???? Sooo confused.

Ok seems i figured out the wideband issue. I had a pretty big exhaust leak near the wideband sensor. I cant believe i never check for leaks.

Had to re do the MAF tune when i got rid of the exhaust leaks and the truck runs really good cruising speed.

It starts sputtering and backfires when small amount of throttle is given and also when giving about 40%. Once we go about half or a little more it backfires then just takes off. Im not sure if it is that it has too much spark timing or injectors are maxing out. When it happens afr stays at 15.0 or when half throttle it stays around 13.0-13.5 and backfires like crazy. Some of it is logged on the logs i posted on my previous post. Thanks for your replies.

Add TPS and your injector information to the logs. That will let you know if you are maxxing the injectors.

I kept forgetting to add tps. By injector data do you mean injector pulse?

Injectors are maxing out around 4k RPMs. Truck is running strong but is in serious need of bigger injectors. Even then it runs really good cruising and at part throttle.

We have been driving the truck around to break in the engine. only need about 200 miles but a wheel bearing went out and will be repaired soon and have torque converter installed, followed by Fast intake mani and fast fuel rails with bigger injectors.

Thanks to everyone for the help, i really appreciate all the replies and help i have been getting. will be sure to keep the build updated for anyone interested.