So I recently picked up a new Chevy SS as my daily driver and after daily driving an 800hp roadster for the last 3 years, the LS3 in this SS seems pretty pathetic. lol. Isn't it funny how power is so relative? For some people a bone stock SS (or Camaro SS/LS3) would be considered a "monster", but when your wife and son's basically stock cars leave you in the dust, you have to do something! For me, it will most likely mean swapping a full LSA into the SS. But for the time being, I've been trying to make the car a little less "pathetic". haha.
The LS3 isn't a bad engine, but there are definitely things in the stock tunes that don't help the way the power is delivered. The off-idle pedal response is actually too strong, probably to make the car "feel" more powerful. The midrange/mid pedal is ok, but it falls on it's face when the revs come up. For me, it makes the engine power/response seem "narrow". In other words, boring and not very versatile.
I need to make one point VERY clear here, ALL I'm talking about is throttle mapping. I'm not talking about making more power, or even moving the power lower or higher. I'm simply talking about the relationship between the pedal and the throttle, nothing else. (Speaking of that, make sure you're logging BOTH the pedal percentage AND the throttle percentage. Almost nobody does. Everybody should!) That's why I figured I'd post this, this is something that anyone can try, with any type of power levels. I'm actually a huge fan of modifying the throttle mapping on just about every engine I work on. There is SO much that can be done with throttle control to make a huge hp engine more manageable, or in this case, make a kinda weak engine "feel" peppier. A lot of tuners stay away from the throttle mapping tables because they're scared to cause a REP or (years ago) possibly brick an ECM. Don't be afraid to experiment, the throttle tables in E67's and E38's are a powerful tool to make an engine feel like you want it to feel.
So in the case of this LS3 in this SS, the stock Desired Throttle Area table actually had the throttle lagging behind the pedal at 62-90% pedal. No wonder the engine felt flat! Between 3000-3500rpm the stock tune actually had the throttle going back down instead of up! WTF? Are they afraid the engine is going to make so much power above 3500 that they needed to reel it back in a little? lol. The other thing that was weird is that the off idle, low pedal percentages had the throttle going pretty far open, quicker than most stock tunes. (Probably why my wife thought the SS felt stronger than her CTS-V during slow around town driving. That's because as soon as you touch the pedal in the SS, the throttle is opening way further than the LSA in her car. Again, throttle mapping can make a 415hp car "feel" faster than a 600hp car. That is until you floor it. haha.)
So here's what I did... Since raising the values in these tables is what often causes REP, I instead lowered the values in the lower pedal percentage/lower rpm areas. (I did fix the backwards throttle movement areas by raising those values though.) The theory, or goal here is to make the initial pedal travel smoother, and also open the throttle as the rpm's rise. By lowering the values at partial pedal, low rpms, but blending them into the stock values at higher rpm's, you end up with an engine that "feels" MUCH more responsive. If you do it right, it will feel like you've gained a pile of torque that builds as the rpm's rise. Call me silly, but I like an engine that builds power as it goes up in rpm's. If the particular engine you have doesn't actually build power like it's supposed to or like you want it to, you can get the same feel by having the throttle open slowly/slightly as the rpm's rise. Again, I need to stress that this is for everyday driving at "normal" pedal or rpm ranges. This doesn't do a thing for WOT.
Anyway, sorry for the long explanation! Just try it! If nothing else, you'll learn how to modify these tables without getting a REP situation. And if you do, just revert back a tune or two and it will be fine. If you do it right, I'm telling you your engine will feel much more responsive and feel more like it just wants to rev. Yeah, some will say it's kinda cheating by making a not so strong engine feel stronger without actually making it stronger, but if it makes your car more enjoyable to drive, isn't that a good thing? And even if I put an LSA in this SS, I still would absolutely not want to leave the throttle mapping tables stock.
Here are some screen shots of my latest values in this LS3 SS to give you an idea of what I'm doing...
This image is the modified table to smooth low pedal/rpm response and increase throttle as rpm's rise...
This shows the differences between what I did and the stock tune...
As you can see in the stock map shown here, the throttle movement rises sharply and then actually falls back in several spots when the rpm rises...
This modified map shows a more gradual rise in throttle movement as pedal or rpm's increase...