Bob T

I've been really impressed with the performance of my stock 3.7 V6 with the exception of the idle to 3k rpm performance. It also doesn't help that I have the 2.73 rear gears. I guess one solution would be to put a 3k stall speed convertor in it, I'm sure that would really do it but I don't want to go there....at least not yet.
When I look at dyno tests of some of the popular bolt ons it looks like an aftermarket throttle body really picks up the bottom end.
What modifications have you done that helped the most with the lack of bottom end torque?
Thanks!

WindyMustang

On mine, the Steeda CAI + BBK TB + a Bama tune (91R or 93R) really did a nice job with beefing up the lower end. Here's my previous thread.

Shorter gears would definitely help with "punch" - but at the expense of gas mileage to a degree.

Hope this helps - and enjoy!

Bob T

Thank you for that well written and detailed report on your results!
I can see following in your footsteps with my modifications.
Looking at your dyno graph I see it picked up substantially at 3000 rpm but looks about the same below 2500.
My problem is I have an automatic, I see you have a manual transmission (I'm jealous). My car is painfully slow accelerating from a stop at idle up to 3000 rpm and then it pulls pretty hard. Since I don't have the advantage of dropping the clutch at 3000+ rpm my car needs help below 2500 rpm too.

Siber Express

Best for mine was the BBK Shorty Headers, brought the low to mid range up to a point that it is useable. Just watch out on how much you open up the exhaust to free flowing will cost you down low.

hogasswild

To echo what others are saying the best low end mods are (in order):
3.73 gears/MPT tune
Shorty headers
73mm throttle body

Mike1Six

Automatic here... My biggest complaint is the hesitation when you first drop the pedal. It's almost like the car bogs down for two or three seconds. I've heard the automatic 5.0's suffer from the same thing. I'm 100% certain it's controlled by the ECM and this can be "tuned" out. My wife's CTS it's fully responsive when you press the pedal and that thing is a POS.

Bob T

Thanks for the responses everyone, very much appreciated.
Mike, I know what you mean about feeling like a bog. I've had my car for around 2 months and I knew that it was strong up top but down on bottom end torque, which isn't surprising for a little V6, but the other day I finally checked out what it felt like flooring it from a dead stop. I almost laughed at the bog and slow acceleration from a dead stop and then it really wakes up at about 3 grand. The lack of bottom end torque is really this engines achilles heal.

Siber Express

With the Shorties running the rest of the exhaust Stock it was a steady pull from around 1500 on up, where before when you hit 3000 RPM it would almost jump.
For the Throttle lag on the Auto a Tuner will get rid of that. I have a Manual so I don't have the Lag taking off in drive but it still had slow Throttle Response hitting the throttle that I lost most of with the Tune.

WindyMustang

Anyone tried a higher stall converter on an auto? That might help a bit too...

Bob T

I've used higher stall speed converters on other cars but not this one.
But I can pretty much guarantee if you put a 3k stall converter in one these cars, end of problem. However a good converter is pretty expensive and a lot more work to install than the other modifications mentioned and probably drop the gas mileage some.
(edit: if feels like the power jumps up at 3000 rpm but then again the torque peak is at 4250 so it may need a little more than a 3k converter if that route is taken)