2009 sierra put in a 450 hp lm7 crate motor had to rebuild it to switch out reluctor wheel and cam gear everything works fine in that neighborhood what I am having trouble with is first start is a little rough
LT bank 1 and 2 shoot up past 25. After about 2000 rpm everything is fine sounds and runs great until back at low idle.
I haven't upgraded fuel injectors yet could that be my problem
Vacuum leak or fuel pressure being low come to mind.
A hopped up 5.3 crank engine that makes 450hp is going to have a camshaft upgrade of some sort done to it so it will need changes to the MAF/VVE to fix all the fueling. But to shoot to +25% right away tells me there is another problem. Depending on how big the stock 2009 fuel injectors are, they might already be plenty large enough for this engine.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
It's says recommended for crate engine 35lbs hr 58 psi
Stock injectors from what I've read should be 28 or 32 lbs hr
I'm new to tuning mostly a stock tune so far
Had to do dod delete not many other tweaks
Look at your tune then, see what size the injectors really are or read the part number off the injector and google it.
The injector flow rate will show it, look for the value around 400-408kpa.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
So the flow rate vs pressure chart
At 408 kpa the flow rate is 29.7 lbs an hour
Flow rate multipliers vs volts, IAT, MAP, FLOW.
are all on a multiple of 1
I'm kinda leaning towards vacuum leak possibly
The Lt banks running +10 range now until I unhook vacuum hoses leading to intake and air intake then they shoot up of coarse
But now I'm getting low readings on MAF
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