We had a chance to dyno a 2003 5.3L Silverado with the Detroit Speedworks Turbo Kit and the base GT-37 turbo. I figured I'd post the results since it's been asked several times, how much power the base kit makes. The truck was fairly stock with the only mods being a Gibson Catback and 4.56 gear. I wish we could have baselined it, but the kit was installed by the customer. I've seen similar stock 5.3L trucks make 225 rwhp / 285 rwtq (some may make a little more, some less).

It made 379 rwhp and 450 rwtq at approximately 6.5-7 lbs of boost.

-Rick

Hmmm....sounds interesting. :D

You have RPM for those numbers, specifically the torque. They look really good.

Sounds like some good numbers....I would have expected 400 rwhp or so at that boost level though.

and that's from the stock kit? what brand dyno was it on? sounds pretty impressive to me.

Excuse my ignorance, but would the 4.56's make any difference in the numbers?

These numbers were on the Dyno-Jet and it made max torque at about 4,100 rpms, however I think the large gear changes the powerband. Max hp was around 4,700 rpms.

-Rick

Excuse my ignorance, but would the 4.56's make any difference in the numbers?

Bigger gears usually show lower dyno numbers.

-Rick

well how does it do in the 1/4, im not a big fan of dynos! I was allways under the impression turbos needed higher gear ratio like 323 0r 308,342 but 4.56 that seems to put not alot of strain on the turbo that it needs or am i wrong? thanks for the help and nice #'s there.

Not sure about 1/4 mile numbers, it just got done today. I would assume it should run pretty good, because it was a regular cab short box.

The Escalade with the same kit weighing 6,055 lbs went 14.2@95 mph at 5 lbs. of boost and 12.88 @ 107 mph with a bad trans and the upgraded GT-67 and 13-14 lbs. of boost.

Below is a video of the Escalade. As you'll see, I was sleeping at the tree and he got me off the line pretty bad. I launched at 3 lbs. and at the 53 second mark in the video you will see the truck torque steer to the right and I let out and get back in it. You'll also hear the stock trans not liking the added power at the 59 second mark, once again I let out for a moment so it would shift and got back in it.

You'll see us doing some testing at the shop, and then the race. (It's loud with an open down pipe)

Escalade 12.88 Pass (http://www.leblancfamily.com/rick7/escalade128.wmv)

and Harlan's Silverado with the GT-67 at approx 12 lbs.

Silverado Video (http://www.leblancfamily.com/rick7/silveradoturbo.wmv)

-Rick

It made 379 rwhp and 450 rwtq at approximately 6.5-7 lbs of boost.

-Rick

Any other changes to the truck other than the turbo, catback and gears?
You would need 10 psi of boost to get to 379 rwhp if you started with 225 rwhp and didn't change anything else. Of course if the truck was already making 260 rwhp before the turbo - then the math would work out right also. Either way it sounds like the truck should FLY!!!!

Any other changes to the truck other than the turbo, catback and gears?

As far as I know, those were the only mods. As I mentioned, we didn't get to baseline to truck, but other 5.3L trucks I've seen it the past made around around 225 stock.

-Rick

Hey Rick

6.5-7psi is with the stock everything on the kit right? I was thinking it was 5psi but, if it's 6.5-7 that'll work. ;)

He has the same kit as you, he just added a $10 manual boost controller.

-Rick

So what are you trying to say, I'm cheap because I don't have a $10 manual boost controller. :huh: :jest: ;)