: How to get more torque, 03-DTS



reinerpump
12-17-05, 12:34 PM
Just got an 03 DTS and it seems to lack bottom end, or at least what I would like. I'm coming off a 99 Park Ave. supercharged 3.8, and I expected the 4.6 northstart to at least be equal to or better, but it's not even close. Granted, the 4.6 goes better at highway speeds (and very well) and would probably beat the blown-3.8 in a drag race, BUT for every day 20-50 mph speeds the blown-3.8 seems to dominate, even at lower rpm's. I'm hoping that I just have a dud 4.6 and it's just needs a fix???? I tought maybe the final drive gearing is the culpril but, the normal little up-hills that the 3.8 used to charge up (at approx. 3000 rpms), makes the 4.6 want to downshift and when it does, it goes (at 3500rpm's or higher) OK, but still no match for the 3.8. any thoughts?

Ranger
12-17-05, 01:18 PM
That is the nature of the beast. The DTS has the 300 HP engine I believe which gives up some low end torque (final drive 3.71). The DHS has 275 HP but more low end torque (final drive 3.11).

turbojimmy
12-17-05, 01:20 PM
The DTS doesn't make its peak torque until pretty high in the RPM range. You can really feel it at 3500 RPM and above. My DTS feels weaker than my mom's base Deville around town but it pulls harder at highway speeds. The 3.8 is a torquey little engine - the torque comes on early and stays pretty flat with the help of the blower. The 300 HP 4.6 also has to lug around considerably more weight.

Jim

reinerpump
12-18-05, 09:57 PM
Thanks for the input, it all makes sense now. I drove my neighbors base deville and it had more lower end as you mentioned. I assumed that the DTS would be better all around, but sounds like they just tweaked the curve. So the questions now is, how did GM tweak it? Is is just programing, or is there any hard parts different? I'd wouldn't mind giving up some top end for better low r's torque. The car is fabulous is highway speeds, and I wouldn't mind sacrificing some of it for better low end.

fpmesiIII
12-19-05, 01:11 AM
test drive the pontiac bonneville GXP you might find your answer has best of both worlds.

turbojimmy
12-19-05, 06:57 AM
Thanks for the input, it all makes sense now. I drove my neighbors base deville and it had more lower end as you mentioned. I assumed that the DTS would be better all around, but sounds like they just tweaked the curve. So the questions now is, how did GM tweak it? Is is just programing, or is there any hard parts different? I'd wouldn't mind giving up some top end for better low r's torque. The car is fabulous is highway speeds, and I wouldn't mind sacrificing some of it for better low end.

The cams are different and I believe the gearing in the trans is different as well.

Jim

reinerpump
12-19-05, 10:16 AM
I've owned many bonneville's and liked the old 80's and 90's model's. The new one was too 'grand-prix' looking for my taste.

Dooman
12-19-05, 10:16 AM
Several times my STS was in for service, they gave me an SLS for daily use. That is the first thing I noticed, more torque on the SLS around town.

Katshot
12-19-05, 11:38 AM
It's a shame Cadillac went with the drivetrain combo they did for the DTS. Persoanlly, I would've used the combo Pontiac went with on the Bonneville GXP. But what do I know? :rolleyes:
Personally, I think it's better to optimize the drivetrain for how the car will be used the majority of the time.

jadcock
12-19-05, 12:48 PM
The differences in the L37 (300hp) and LD8 (275hp) drivetrains lie solely in the intake camshaft profiles, and computer tuning to accomplish this. Each engine also got its own final drive ratios, at least in Cadillacs. L37 got 3.71:1 final drives, to help them overcome the relative lack of lower end torque. The LD8 got 3.11:1 final drives to better fuel economy on those cars.

I agree with Katshot -- the best of both worlds, in my opinion (and his) is the drivetrain in the Pontiac Bonneville GXP. The LD8 engine with the 3.71:1 final drive. It posted respectable 0-60 times also (mid-6s if I recall correctly).

reinerpump
12-19-05, 02:14 PM
thanks for the answers, clears it up. sound like i would like the LD8/3.71 too, as in the Bonny. bonny was out though as i'm 40 something and like the dts 'look' better, for me. for the record, whats the combo in the new lucurne and new DTS?

jadcock
12-19-05, 04:02 PM
The new DTS can be had with both combinations I believe. There is no "Deville" name anymore -- they're all called "DTS" now. So I think you can still get the L37/3.71 or LD8/3.11 combination. Not sure on the Lucerne.