
Coming soon in 2007, we
will have our 2007 GM Silverado crew cab featured on several episodes
of Truck U on Speed Channel. This truck features GM's new
displacement on demand 5.3L engine. I will be updating this as I
get more information from Matt and Bruno at Truck U, regarding
additional contributors, and air dates. A special thanks to the
team at Truck U, and the generous contributors for the great
products we will be adding to this vehicle. We will be displaying
this vehicle at the 2007 SEMA show in Las Vegas.
This was a tricky one
to get a good sound out of. We tested dozens of designs of
mufflers to find just the right combination. We needed something
that flows better than o.e. and gives a nice performance sound.
This was not hard to do. What was difficult, was getting the
vehicle to have a nice sound when it is up to speed, the engine is
warmed up, and running in 4 cylinder mode, with the displacement on
demand system engaged. If you can imagine your muscular sounding
V8 pickup all of a sudden sounding like a sport compact 4 cylinder car
with the big muffler and tip on it, you get the picture. Through
dozens of hours in muffler design, flowbench testing, and road testing
for sound, we came up with a specially-tuned muffler for the
displacement on demand engines. (All 2007 new body style
Silverado 5.3L pickups have the displacement on demand system).
The sound in 8 cylinder mode in the cab is a little more aggressive
than o.e., and more noticeable at the tail pipes. In 4 cylinder
mode, a small change in pitch is noticed, a little more than the o.e.
pitch, but very liveable and not annoying. In all honesty, we
were hoping for a little bit more aggressive sound inside and at the
rear, but through extensive sound testing, found the quieter sound to
be much more liveable in the cab when in 4 cylinder mode. We felt
this would be a better product.
Click on the following
link to see pictures of the kit installed at our shop on this
vehicle: http://www.heartthrobexhaustinc.com/2005820p.html









