2015 Whipplerado project
 

Target vehicle is a '15 Silverado LTZ, 4 wheel drive 5.3L, 6 speed auto w/ k&n diy air filter, in oem air box.

Goal is to get as much power to the wheels (550-600 rwhp) with a safe tune, using hpt and with the following items being gathered.

1) Whipple 2.9L tuner kit, with extra 6.2L parts and their latest higher volume IC pump, 4.375" and 4.0" pullies.
2) Dedicated motorsports harness w/ 3 bar map sensor
3) 91mm throttle body from a 6.2L
4) Autometer pro series digital wideband gauge, Glowshift dual IAT gauge and digital vacuum/boost gauge and Autometer 3 gauge pillar mounted pod.
6) hpt pro interface on windows 10 laptop, installed and working
7) 3 bar map sensor
8) hp tuners software
9) 2 young wrenches and 1 old guy

phase 1 complete, blower installed and tuned (rich at the moment), 4" sc pulley, 11.5 psi boost. phase 2 started (LT4 cam, springs, L86 injectors)

Latest update:

WOW...what a steep learning curve on the hpt software and on this vehicle !!

anyhow, injectors are swapped out and without the $1000 worth of special tools. Valve springs are in as well

working on the cam swap, which has turned out to be interesting to say the least. For anyone with a similar motor and/or vehicle, the oil pump needs to come off of the front of the crank and that requires lowering the oil pan, which on a 4 wheel drive can be a bit lengthy....at the moment, I still have 1 almost unreachable bolt to loosen up (or grind a groove into the pan...(ouch)

here is an interesting link to the tty control valve solenoid problem that could crop up and throw tuning out the door

Sticking Camshaft Position Actuator Solenoid Valve

outside of that I think that the unrestricted fuel line that was recommended, was possibly a waste of money, in that the fuel rail entries have very small entry holes as well

more to come...

What about headers and exhaust. With all that air going in you gotta let it out.

I hear you. It's my son's truck and he has no muffler on it at the moment. He loves the sound, no drone , etc. That said, I've seen kooks long tubes without cats on sale. currently he still has the 2 cats up front and 1 (cat?) after the y pipe. from there it goes thru a flex connector and out the side, just ahead of the rear wheel. the flapper is open always. truck sounds pretty good!!

Please educate me as to why some trucks drone, etc and whether the kooks with or without cats , would be a good choice. and if so, 1 3/4 or 1 7/8" primary tubes??

The possible exhaust restriction might be why boost is over 11.5 psi with the 4" pulley.

Will see shortly how it goes with the LT4 cam and 6.2L injectors

thanks for the feedback

If you can't get it out, you can't get it in !!

Cat converters remove rasp because they are resonator basically. A short chambered muffler will drone just because of the design.

It all depends on the setup for why they drone, lack of resonator or wrong style muffler will create the rasp and drone. Running converters or a longer straight through muffler with an additional resonator or j-pipe can cancel out rasp/drone and make it sound good.

how does the j pipe work??

I've seen pics on KB's Silverado but didn't really understand how it installs or works

thx

"They work by being open to the exhaust before the muffler, 1/4 of the length as long as one of the resonant soundwaves, and capped at the other end. The sound wave is then reflected back into the exhaust at 1/2 wavelength, perfectly out of sync with the wavelength that's coming after it, thereby canceling it out."

More here: https://www.performancetrucks.net/fo...-drone-489463/

cool stuff....thanks

Headers will def reduce boost pressure. BTW the LT-1 or L86 TB is 87mm not 91mm

RT

While also increasing power and torque

yes, I clarified the tb sizes in a nother thread, thanks

headers not happening immediately