99 4.8 longtube headers and no cats QUESTION

[tanz45]

Driving a 99' Silverado with the baby 4.8. If I install long tube headers with no cats, am i going to get lean codes? If so, will larger injectors help solve this. Or, what is another alternative fix? Also, not like this truck is drivin wide open all the time. Am i going to lose all my pull out power because of the extremely low back pressure?

[ducky]

Driving a 99' Silverado with the baby 4.8. If I install long tube headers with no cats, am i going to get lean codes? If so, will larger injectors help solve this. Or, what is another alternative fix? Also, not like this truck is drivin wide open all the time. Am i going to lose all my pull out power because of the extremely low back pressure?

You shouldnt get any kind of lean codes. Your rear 02s will throw a code but u can get those turned off

[mean05]

no lean codes but you should throw about 4-6 o2 codes...any tuner can turn them off for you no problemo

[BossGMC]

If you do the swap, the only codes will be for catalytic converter effieciency below threshold bank 1 and bank 2 as well as o2 sensor circuit high and heater voltage high for o2's 1/2 and 2/2, wont hurt driveability, loss of backpressure will be compensated by midrange torque increase because the long tube headers, and strongly recommend Nelson tune to eliminate the Service Engine light as well as a power tune even over the mail, call him with all your specs and bolt-ons, he will custom tune a ECU for you send it to you and all you have to do it swap it with your old one and return your old one back to him...

[tanz45]

Thanks for the input. Appriciate the help.

[ff_jeff]

you wont loose any low end. It may feel like it a little, but thats because you will pick up top end. Call Nelson performance and with a custom tune you will have a whole new truck. Look for a full second off the 1/4 mile.