ls7 tuned

**gashkerwin** · 11-27-2009, 11:36 AM

Just wondering if anyone out there has seen or heard the gains by tuning an ls7? I've searched around and have yet to see anything about an otherwise stock ls7 with a tune on it.

**shady milkman** · 11-27-2009, 01:03 PM

Originally Posted by gashkerwin

Just wondering if anyone out there has seen or heard the gains by tuning an ls7? I've searched around and have yet to see anything about an otherwise stock ls7 with a tune on it.

if the ls7 is stock i have heard around 15 horses can be had.

**gashkerwin** · 11-27-2009, 01:13 PM

Wow, thats it eh? Hmm. I mean, the ls7 has to come from the factory with a 91 tune on it right? I'd think on an engine that size the difference between a 91 and a 93 tune would be more than that...

**00z28bubba** · 11-27-2009, 05:16 PM

depends all on what you can get. no point in tuning for 93 here unless you mix your own gas or know the certain spots that sell 93. which here is very few that sell 93. that is assuming there are places in town lol. besides 2 octane is not much at all to begin with. so a bone stock crate motor shouldnt get much increase in power at all. 15 hp is all of 3% of the overall 505 hp. that is within dyno error. most dynos that are running properly have on average a 3% error window. so that could just be a dyno on monday vs the same dyno on teusday. hard to say whether that is an actual increase unless you have access to multiple dynos.

**shady milkman** · 11-28-2009, 10:49 AM

Originally Posted by 00z28bubba

depends all on what you can get. no point in tuning for 93 here unless you mix your own gas or know the certain spots that sell 93. which here is very few that sell 93. that is assuming there are places in town lol. besides 2 octane is not much at all to begin with. so a bone stock crate motor shouldnt get much increase in power at all. 15 hp is all of 3% of the overall 505 hp. that is within dyno error. most dynos that are running properly have on average a 3% error window. so that could just be a dyno on monday vs the same dyno on teusday. hard to say whether that is an actual increase unless you have access to multiple dynos.

wait..are you saying tuning may not increase performance in a stock ls7 ? seriously ?

**Frost** · 11-28-2009, 09:07 PM

Originally Posted by gashkerwin

Just wondering if anyone out there has seen or heard the gains by tuning an ls7? I've searched around and have yet to see anything about an otherwise stock ls7 with a tune on it.

http://www.ls1.com/forums/showthread.php?t=76332

**gashkerwin** · 11-28-2009, 10:22 PM

In that thread you say that the 423/395 stock is a bit low. Not sure why that is. 505*.85 = 429, and I'll call 1% error close enough. Am I missing something? Do those cars use a lighter enough driveline that 10% loss of engine to wheels is appropriate? I haven't heard anything about the Ls7s being factory underrated like the LS1s in certain cars were vs others.

Now, I can buy the tq being a bit lower than I would have guessed at, given that the LS7 is supposed to be 11:1. Had I need to go guess I would have thought the tq would be somewhere in the 430 range too, maybe more.

I will say that getting 50/50 from a catback, lid and tune is pretty impressive, since with the C6s Chevy seems to have paid attention to putting better flowing exhaust on from the factory.

**Frost** · 11-29-2009, 10:15 AM

Originally Posted by gashkerwin

In that thread you say that the 423/395 stock is a bit low. Not sure why that is. 505*.85 = 429, and I'll call 1% error close enough. Am I missing something? Do those cars use a lighter enough driveline that 10% loss of engine to wheels is appropriate? I haven't heard anything about the Ls7s being factory underrated like the LS1s in certain cars were vs others. .....

No need for theoretics, I saw that was low because I typically see 430-445 rwhp from the cars once they have more than 1200 or so miles on them.

But yes, to be honest, you get REALLY close to 50rwhp form just a cold air kit and a tune!

**00z28bubba** · 11-29-2009, 05:32 PM

Originally Posted by shady milkman

wait..are you saying tuning may not increase performance in a stock ls7 ? seriously ?

it just falls into that infamous dyno error range. for a 505 hp engine, 15 hp just isnt the same increase compared to a 350 hp engine. especially when we are looking at this scenario numerically. i highly doubt that 15 hp is gonna be a huge increase in e.t.s aswell.

**Frost** · 11-29-2009, 09:42 PM

Originally Posted by 00z28bubba

.....

The dyno I use is repeatable within about 2hp at that level; backed up by hundreds and hundreds of pulls and corrected to SAE.

To regularly see 20-30 RWHP on a car (that really is the range) that makes 430 stock is still 7%. The gains from tuning alone usually are the same as a premium set of long tube headers on these engines.