Spencer11

Recently did a motor swap on my truck, truck Norris cam and 4l80e to go with the 5.3.

I am having idle issues in parking lots and at stop signs likely because of not enough air. My scanner doesn’t show me IAC counts but it smells rich. I have drilled the whole in the throttle body about 2/32 larger and it is better because it previously didn’t run at all basically. Not sure if I need to drill more but I can’t adjust set screw either to open the plate because it’s not resetting the tps %(I have done proper relearn procedure).

tuner is going to see if the low idle is a problem

set at 525 in gear 💀. No idea why but the air still seems to be the main limiting problem. shoot your opinion I’m open to anything.

RPM WS6

iTrader: (3)

Factory LS1 cam is set to idle at 550rpm in gear, 650rpm in P/N. Not sure on the specs of your cam, but any aftermarket performance cam is going to have more overlap and want a higher idle speed if anything, not lower. Why is it set to 525rpm? Even with a mild performance cam I'd do at least 600-650 in gear; idle should be much more stable that way.

Spencer11

“Tuner Oversight”. Maybe, he will let me know Tuesday, he’s on vacation. Cam has big overlap I think. I’m not too informed on cams. Truck Norris cam

RPM WS6

iTrader: (3)

I don't know anything about that cam specifically, but the aggressive cams with considerable overlap will usually require idle speeds anywhere in the range of 700-1000rpm (obviously only the really extreme stuff would need to be at the high end of that). Most moderate performance street cams will idle well in the 700-850rpm range, depending on specs and how well all aspects are tuned. Higher idle speeds can create an issue if you have a stock torque converter, but if the cam needs an idle speed that high then it really shouldn't be paired with a stock converter in the first place.

Either way, I'd address the tuning before doing any more drilling or modifications to the throttle body.

Spencer11

yep. That’s where I’m at, I should have an answer by next week.

torque converter is 3000-3200 stall from circle d.

RPM WS6

iTrader: (3)

That's good news; raising the idle speed shouldn't present any problems then.

jetech

Is the fuel system completely factory stock 5.3( injectors, fuel rail/pressure regulator, pump)? Did the tuner have the Truck Norris cam specs? What year 5.3l and do you know the RPO code ? Some were flex fuel which have injectors that flow more than gas only 5.3l's so the tuner would have needed to know the flow rate of the injectors if he didn't have the p/n of the injectors

Spencer11

tuner covered all of that, it runs fine except for being rich at idle due to large cam and stock tb I’m still adjusting. I’ll update when tuner comes back with more info/ new tune.

as far as the injectors idk but I don’t think it’s messed up because it’s running right just dies sometimes.

jetech

The Truck Norris cam is not a big cam, it just has a very narrow LSA for fuel injection. It has nothing to do with the factory stock tb. I am running a larger camshaft in a 6.0l with the factory tb and it drives great. Just be sure to give the tuner ALL the information he needs. Since you said you are still adjusting tb must be a "99-"02 5.3l ? DBC I have to ask...are you sure it is a 5.3l?

Spencer11

100% sure it’s a 5.3….i did a full rebuild. Did you have any adjustments for your idle? Or just ran it how it was from factory?

I am gonna let the tuner know the type of injectors tmr, they are the non flex fuel but just gonna make sure we got that right.

Spencer11

Sorry, I’m confused what you are asking. It’s a 2002 Silverado, had a 4.3 now a 5.3. Drive by cable throttle body stock, I have had to drill the hole in TB bigger to improve idle and has so far helped. Still smells rich and occasionally dies.

billyhoss

iTrader: (1)

that is not a big cam by any means. you will need to get the idle up a little and get something to count the IAC steps. do not drill the hole anymore or once you get a scanner that can see the count and try and get it within range it could act funny again cause of the larger hole!

jetech

Spencer11 my setup is an LQ9 from a Cadillac Escalade. It has DBW so idle was all by tune