: What R the best performance mods you would recommend for an 08 STS Northstar?



jimzilla
06-08-09, 06:18 PM
Hello all. I have recently purchased another STS, this one an 08 Black on Black with Northstar and minimal options. I am interested in performance upgrades that group members have put on and would recommend as big bang for the buck ...but let me know as well as dont waste your time ones either so we can all benefit....Let me know. Thanks

EChas3
06-08-09, 06:52 PM
If your priority is performance, get a V.

STE_6000
06-08-09, 06:58 PM
so far the cold air intake is a big notice, and sounds good to when you lay into it. it is a pain in the butt to get in if you use there tube.

c5 rv
06-08-09, 07:58 PM
Slap a "Type R" badge on the lower right side of the trunk lid. Ricers will fear you.

stevenriz
06-09-09, 07:17 AM
hahaha that's a Honda emblem right?

bbshriver
06-09-09, 08:28 AM
so far the cold air intake is a big notice, and sounds good to when you lay into it. it is a pain in the butt to get in if you use there tube.

What intake do you have? How do you notice it? I noticed K&N did not have one for the V8 (I have a 2005 if that makes any difference?)

BaTu
06-09-09, 09:46 AM
These engines are Made to be performance powerplants. These simply IS no "free horsepower" like in most other cars. Any easy gains have already been incorporated into the design.

If you want to squeeze more ponies out of it you're going to have to go further than things like "air filters" and start with things that the designers can't do and maybe make changes that will increase pollutants. So, I think we're talking software mods and really, even then, you're not going to find a whole lot of improvement just there for the taking...

You want to go Alot faster, I agree with the previous poster, dig deep and go for the V ;)

bbshriver
06-09-09, 10:03 AM
More "performance" than a Z06, or regular corvette than that matter? or any production car? Even with Ferarri there are big gains to be made with simple things like exhaust.
The Northstar is 320HP. Ford has 315HP and more torque (325 versus 315 for N*) from a SOHC 3 valve engine versus Caddy's DOHC 4 valve..

I love my Northstar, but there's plenty of areas that could be improved, 320HP from 4.6L isn't exactly ground breaking. Exhaust is probably the biggest restriction since the cars are so freakin quiet (as soon as I have some $$ I'm doing *something* about that, not sure what yet though).

Car & Driver got someting like 25 ft lb extra on a WRX just from a K&N FIPK, and I'd venture to say the WRX is a bit more of a "performance machine" than the STS.


These engines are Made to be performance powerplants. These simply IS no "free horsepower" like in most other cars. Any easy gains have already been incorporated into the design.

If you want to squeeze more ponies out of it you're going to have to go further than things like "air filters" and start with things that the designers can't do and maybe make changes that will increase pollutants. So, I think we're talking software mods and really, even then, you're not going to find a whole lot of improvement just there for the taking...

You want to go Alot faster, I agree with the previous poster, dig deep and go for the V ;)

BaTu
06-09-09, 10:19 AM
So you think there's a built-in power restriction in the exhaust system and that Cadillac is just saving the cost of the larger pipe to give it to you?

I'm sure everything is a trade-off between performance & driveability/noise/pollution/longevity (that K&N will let WAY more dirt through) etc.

And sure, cams, compression ratio, tubo/superchargers will yield significant results but, you're kidding yourself if you think there's an inexpensive quick-fix you can do to relieve HP robbing factory parts that you'll actually notice.....

bbshriver
06-09-09, 10:32 AM
No, I think that extra restriction is because lots of buyers don't want loud cars. Likewise most air-intake boxes (best I can tell the caddy is no different) include lots of "silencer" chambers, and odd shapes that mess up your air flow into the engine. Performance and efficiency are sacraficed for the sake of silence and whatever other guidelines GM has. I don't work for GM so I don't know, but I do have a degree in automotive engineering, and know lots of GM engineers, people involved in testing, aftermarket, and I've been messing around with cars for long enough to know that NO major manufacturer makes a hardcore performance powerplant out of the factory. Even the beloved CTS V-II has a signifigantly de-tuned version of the Corvette LS9. Cadillac is not, nor is it intended to be a "performance machine"

Even if it were, per my previous statement even Ferarri (which *is* intended to be a cost is no object performance machine) can get lots of extra power/tq from exhaust. For reference here is a dyno graph stock versus aftermarket exhaust on a 360 Challenge Stradale (the "hot rod" version of the 360).
http://www.ricambiamerica.com/hyperflowdyno.htm

Yes, when you deviate from stock there are trade offs.. less restrictive exhaust systems *generally* are louder, some people don't want that. Same for air intakes. K&N air filters do offer less filtering, however the main benefit is in the tubing not in the filter, and you can buy top quality filters to replace the K&N element.
Also, I don't know what you mean by "free horsepower". a K&N is around $300, exhaust around $1k. I dunno about you, but that's not "free" to me.



So you think there's a built-in power restriction in the exhaust system and that Cadillac is just saving the cost of the larger pipe to give it to you?

I'm sure everything is a trade-off between performance & driveability/noise/pollution/longevity (that K&N will let WAY more dirt through) etc.

And sure, cams, compression ratio, tubo/superchargers will yield significant results but, you're kidding yourself if you think there's an inexpensive quick-fix you can do to relieve HP robbing factory parts that you'll actually notice.....

BaTu
06-09-09, 10:52 AM
OK, I agree, you put on a Corsa exhaust and K&N induction to the tune of say, $1,300 if you do it yourself and your numbers are up some. You think for all that effort and money you have a significant performance increase???

Or does it really just sound and feel like you've got a lot more HP? ;)

I can't imaging it would be worth the, improved, track results and much as the feeling you'd have about it.

I still say, go with a V and you'd be better off in the long run (and hey, you could start dumping the Thousands of $$ into THAT too... )

How 'bout weight?? Start stripping her and there's Plenty of free HP available :)

Get out the sawsall!!! -> http://forums.vwvortex.com/zerothread?id=776885

bbshriver
06-09-09, 11:07 AM
I'm just not sure what you were talking about with "free" power? And the OP didn't ask about free power either, just asked what's the best value. If you want more power (though you really want more torque) exhaust and intake are two places that are often limiting factors. Of course you could do new cams, porting and polishing etc too, but that's a whole nother discussion.

Interestingly the car and driver article I referenced found that having an intake AND an exhaust was less effective than the intake by itself, until they reprogrammed the computer. (oh, and that can be done on the STS 2006+ too, lots of discussion on that in the V forum).

As for me personally... I find my car to have adequate power, but I do want better noises coming from the exhaust.. That should/may result in more HP also but I don't really care. Air intake.. not worth $300 to me at this point, but it might be to someone else. I may do it someday but I have other things to spend $ on (Jeep, Porsche, Harley and other hobbies)

As far as the V... from what I gather they ride more firmly than the regular STS... I bought the STS because I wanted a luxury car that would coddle me for long trips (just took a 10 hr each way to Michigan last weekend, 14 hr to Florida in 2 weeks). I originally wanted a 1995 Fleetwood, but decided I wanted something newer with a warranty. I like a soft cushy ride, and my base V8 has a pretty good ride, though it could be softer. And besides that I paid $10k less for my car than what I've seen V's for.. If you have the $ for a V and that's what you want, it's probablly fine. But I didn't have the $ AND it's not what I want.. I'd like the engine/drivetrain, but not suspension. Then again i do like my 2.73 rear end and 25mpg.

Maybe my first post was misleading... It just seemed you were implying there was no room for improvement in the STS. I agree there is no "free" power. You have to pay $$ and maybe trade off something else. I was just saying that every mass produced car is a trade off and the STS is far from a performance machine. It's a luxury car with some performance aspirations.


OK, I agree, you put on a Corsa exhaust and K&N induction to the tune of say, $1,300 if you do it yourself and your numbers are up some. You think for all that effort and money you have a significant performance increase???

Or does it really just sound and feel like you've got a lot more HP? ;)

I can't imaging it would be worth the, improved, track results and much as the feeling you'd have about it.

I still say, go with a V and you'd be better off in the long run (and hey, you could start dumping the Thousands of $$ into THAT too... )

How 'bout weight?? Start stripping her and there's Plenty of free HP available :)

Get out the sawsall!!! -> http://forums.vwvortex.com/zerothread?id=776885

WillySTS
06-09-09, 11:41 AM
OK, I agree, you put on a Corsa exhaust and K&N induction to the tune of say, $1,300 if you do it yourself and your numbers are up some. You think for all that effort and money you have a significant performance increase???

Or does it really just sound and feel like you've got a lot more HP? ;)

I can't imaging it would be worth the, improved, track results and much as the feeling you'd have about it.

I still say, go with a V and you'd be better off in the long run (and hey, you could start dumping the Thousands of $$ into THAT too... )

How 'bout weight?? Start stripping her and there's Plenty of free HP available :)

Get out the sawsall!!! -> http://forums.vwvortex.com/zerothread?id=776885

I agree. I have modded every car I ever owned with the exception of 1, a 1990 Eldorado, which I just didn't get around to doing it, and I can tell you that there is no better free hp than removal of weight. But that is unreasonable on a Cadillac.

But, I can tell you this...the most reasonable thing one can do for performance is to get a reprogrammed ecm, such as available from Wait4Me performance, could get you 10-15 hp, mabe. An intake system may get you 5-7 hp, I believe Volant makes one and the exhaust(whoever's, make no difference) MIGHT get you 2-3 hp. The one thing that worked well on past vehicles is to lower the gear ratio in the rear end, but that is borderline unreasonable in a Caddy, especially if you already have a 6 speed. And everybody knows there is no better bang for the buck than the bottle.

BaTu
06-09-09, 11:52 AM
I was just saying that every mass produced car is a trade off and the STS is far from a performance machine. It's a luxury car with some performance aspirations.

I don't think that's quite true..... Powerplant performance is a much larger criteria for the NorthStar over most "mass produced" cars. The "NorthStar guys" have always tried to squeeze every bit of performance, with in the restrictions OF a luxury car, that they can I'm sure. And come ON,,,,, the suspension is CERTAINLY designed around performance (MagRide, aluminum A-arms, sway bars etc.) I'll agree you can't call it a "Sports Car" but to say it's not a "performance machine" in inaccurate (maybe you should have gone with your instinct and purchased that "boat" of a Fleetwood) ;)

They leave no "stone unturned" in looking for power a robbing item that can be changed for "free" (for them) like restrictions. I don't know about the WRX team (all though I Love to hear Their side of the 25hp loss that they could let slip between their fingers ;) ) but I'd be surprised if there's much of that in ANY design team where performance is such a consideration (nothing Ferarri does surprises me though, those guys Totally have their head-up-their-a$$es (I speak this as an owner)).

Reading it in some magazine "don't make it so" :D (I know, I'm Such a cynic... ;) )

bbshriver
06-09-09, 12:10 PM
You know how many Northstar engineers?

And what are you calling "mass produced" cars? Corvette's have a long history of not being developed anywhere near the max, and I'd venture that they're much more performance oriented than the STS.

The Northstar started out as a 270HP FWD engine.. Surely you're not trying to say they've always been squeezing every bit of performance out of it. 320HP isn't bad, but it's not really impressive for a 4.6L when Ford gets the same in a Mustang, Audi gets 340 with a 4.2, Jaguar is 300 with a 4.2

If you're saying performance is a higher criteria for Northstar than say... a toyota corolla, I'd agree with you. When I say mass produced car I'm talking about comparable cars (BMW, Mercedes, even Ferarri, Bentley are "mass produced")

Perhaps the Magride version is more performance oriented, I don't have MRC, nor do I want it on my car. If I want handling I'll just drive my Porsche (1973 911).

And yes, Ferarri does some very odd things. My dad has a 550. Wonderful car, but why use rubber that melts for the interior. And dumbest idea ever=fuel pumps mounted in tank on rubber isolators. Still, there's not many cars that are as comfortable humming along at 120. Bentley Arnage is good too.

Another thing I forgot to mention about the trade off is almost all OEM's are VERY conservative from a durability standpoint. Remember if anything breaks, they are expected to fix it during the warranty period. A friend of mine who was an engineer for Saleen was always frustrated because people were wowed by the likes of Rousch and Lingenfelter who had much more impressive numbers (HP, torque, aceleration) than Saleen, but "those people don't understand, we have to warranty our cars so we have to have safety margins"




I don't think that's quite true..... Powerplant performance is a much larger criteria for the NorthStar over most "mass produced" cars. The "NorthStar guys" have always tried to squeeze every bit of performance, with in the restrictions OF a luxury car, that they can I'm sure. And come ON,,,,, the suspension is CERTAINLY designed around performance (MagRide, aluminum A-arms, sway bars etc.) I'll agree you can't call it a "Sports Car" but to say it's not a "performance machine" in inaccurate (maybe you should have gone with your instinct and purchased that "boat" of a Fleetwood) ;)

They leave no "stone unturned" in looking for power a robbing item that can be changed for "free" (for them) like restrictions. I don't know about the WRX team (all though I Love to hear Their side of the 25hp loss that they could let slip between their fingers ;) ) but I'd be surprised if there's much of that in ANY design team where performance is such a consideration (nothing Ferarri does surprises me though, those guys Totally have their head-up-their-a$ (I speak this as an owner)).

Reading it in some magazine "don't make it so" :D (I know, I'm Such a cynic... ;) )

trackbait
06-09-09, 04:34 PM
With an 08, with a lot of warranty left, I would probably be cautious what sorts of mods you do. . Even small ones like CAI. And with GM in turmoil, the last thing they want to do is find a way to pay a warranty claim that may have some wiggle room built in because it was not OEM anymore.

I recectly ran across a situation with my 08 and Corsa (and Caddy) saying the 08+ STS are not the same exhaust therefore Caddy and aftermarket are reluctant to fit one on the 08's.

I called GM / Caddy dealer and asked about this. They both (Corsa and Caddy) said it was not that anything changed on the Corsa Muffler but the rear hangers are different for the 08 - so a slight welding mod has to be done to make them fit like on the pre 08's. I was assurred by GM, that given no change in the muffler, there would not or ever be any problem with some sort of warranty claim which may be construed to have had anything to do with the exhaust. So, I'm feeling pretty good now and the 08's got a new pair of Corsa's and the sound is AWESOME! And, I can't help but think that I seem to recognize a little better response now at the expense of a heavier foot.


BTW.... if anyone wants a Corsa exhaust I know where I can get brand new - still in the box- set for around $550 and with the mod for the rear hangers to make a true bolt on system (which I can do) around $600... Corsa Pt number 14157.

Good luck making more juice ---> :cloud9:

jimzilla
06-09-09, 09:24 PM
Trackbait, do you have an email that I can contact you at? I cant PM you for soem reason. Thanks Jim

dkozloski
06-10-09, 04:12 PM
As Stroker McGurk says, "You can't feel less than 10% in the seat of your pants". Save your money.

Dr. Design
06-10-09, 05:31 PM
Hello,
Congrats on the new car. The best bang for your buck upgrades would be as follows:
Air Intake System
ECU Tune
Corsa Exhaust

Other than that there are not a bunch of options out there for your vehicle. Unless you get into custom builds, that is basically it. Let us know if you need any parts.

Thank you,

Dr. Design
D3 Cadillac



Hello all. I have recently purchased another STS, this one an 08 Black on Black with Northstar and minimal options. I am interested in performance upgrades that group members have put on and would recommend as big bang for the buck ...but let me know as well as dont waste your time ones either so we can all benefit....Let me know. Thanks

lreddiablo
06-10-09, 07:00 PM
Does D3 do an ECU tune for an '05 STS4 V8? I contacted blackbear performance and they said that they changed it late '06 and blackbear cant do the pre-late '06 STS. Also if so, how much do you charge?

amgqmp1
06-10-09, 07:48 PM
Another thing I forgot to mention about the trade off is almost all OEM's are VERY conservative from a durability standpoint. Remember if anything breaks, they are expected to fix it during the warranty period.

100% agreed. GM had a game plan with the STS...and that was to be class competitive while still appealing to their niche. The STS-V was for the enthusiast crowd (may it rest in peace). I think it was fairly aggressive considering the average age of a new Cadillac buyer. 300HP+ is already asking for trouble at the average age range...then toss in rear wheel drive. Let's just say that I wouldn't want my mom driving my car in the winter...and she's still a few years from 60.

You and I are likely very happy with our STS the way it came from the factory as we seem to have been looking for similar things (e.g. I also am doing quite fine without MRC).

I wish there was more of an aftermarket for the STS, but I understand why there isn't. Kudos to D3 for offering what you do.

Dr. Design
06-10-09, 08:22 PM
Hello,
We can hardwire an ECU box and adjust the air fuel ratios on all year STS's. However if you want to get into ECU tuning via reflash, the vehicle would have to be a late 06 model and up to do the reflash. The early gen computers are not considered "tunable". ECU tuning starts at $350 depending on what is being done to the vehicle.

Thank you,

Dr. Design
D3 Cadillac


Does D3 do an ECU tune for an '05 STS4 V8? I contacted blackbear performance and they said that they changed it late '06 and blackbear cant do the pre-late '06 STS. Also if so, how much do you charge?

jamesbalzer
06-10-09, 10:52 PM
Let's remember that these are Cadillac sedans in MILD performance form. I challenge any Corvette, Ferrari, or other High Performance car to compete with our Cadillacs on comfort, road-noise, wind-noise or ride quality. It must be noted that Cadillac never intended the STS to be a weekend racer. They have their purpose and intended market and the 10 second club isn't it. If "Go Fast" is a major concern, buy the appropriate car! Nothing irritates me more than the bonehead in the Escalade on 38" Swampers with straight pipes. Now, it rides rough and is loud as hell. Why did he buy the freakin Escalade????

bbshriver
06-11-09, 08:21 AM
Can you please explain what you mean by "hardwire an ECU box"??

I too have a 2005 and may be interested in ECU changes after intake and exhaust..


Hello,
We can hardwire an ECU box and adjust the air fuel ratios on all year STS's. However if you want to get into ECU tuning via reflash, the vehicle would have to be a late 06 model and up to do the reflash. The early gen computers are not considered "tunable". ECU tuning starts at $350 depending on what is being done to the vehicle.

Thank you,

Dr. Design
D3 Cadillac

Dr. Design
06-11-09, 02:36 PM
Normally our ECU box would plug into the factory MAF connector and the engine harness with factory style connectors. By hard wiring it we would have to physically be spliced into the MAF harness allowing the ECU box to communicate with the vehicles computer. I can't recall off the top of my head, but I think it is like 4 or 5 wires off the harness that need to be connected to. I hope that helps, let us know if there are any other questions.
Thank you,

Dr. Design
D3 Cadillac



Can you please explain what you mean by "hardwire an ECU box"??

I too have a 2005 and may be interested in ECU changes after intake and exhaust..

bbshriver
06-11-09, 02:54 PM
Sounds like this would be a bit of a risky move as long as I'm still under warranty.


Normally our ECU box would plug into the factory MAF connector and the engine harness with factory style connectors. By hard wiring it we would have to physically be spliced into the MAF harness allowing the ECU box to communicate with the vehicles computer. I can't recall off the top of my head, but I think it is like 4 or 5 wires off the harness that need to be connected to. I hope that helps, let us know if there are any other questions.
Thank you,

Dr. Design
D3 Cadillac

Dr. Design
06-11-09, 03:06 PM
Correct, that is why we don't really offer it as an option understanding most people wouldn't want to cut into their harness. But it is really up to the owner, we are just giving them options.

Thank you,

Dr. Design
D3 Cadillac


Sounds like this would be a bit of a risky move as long as I'm still under warranty.

bbshriver
06-11-09, 06:18 PM
Anyone used this, or even know what it really does?
http://www.summitracing.com/parts/NAL-12578953/Application/?query=Year|2005|Make|CADILLAC|Model|STS&prefilter=1

next2pool
06-11-09, 06:39 PM
Engines are better compressors than vacuum pumps, so opening up the intake usually helps more than opening the exhaust. Although muffler restriction can be a big deal, even quiet ones can have low restriction--volume is usually the key to low noise but there's only so much room. Also, bends and indentations in pipes are dramatically more of a problem than diameter alone.

Platinum06
08-08-09, 03:41 AM
I like quiet go...

K STS
08-08-09, 10:20 AM
I'm still at a loss trying to figure out how to get this 3.42 carrier to work in my 2.73 STS. I have an early 2006, so it is not tuneable. I contacted GM and techline to possibly get my ECU re-calibrated, but they are giving me the run around as well.

The next step would be to try to repin a 2007 ECM, and then flash it to a 2007 VIN with my exact same options. Then tune that.

Warranty is up in 9,000 miles. Then it may be time for the carrier swap, tune, and nitrous. It sucks having no one in the world basically wanting to do what I do.

Lifer
08-08-09, 11:20 AM
If I increase the performance of my Northstar- equiped STS I will sit in traffic so much faster.

Mine is a daily Get-To-and-Back-From-Work machine on the most crowded set of go-nowhere highways in the south (Dallas-Ft Worth) 20, 30, 75, 35E, 35W, 635, 121, 190, and then there is DOWNTOWN!!!

Superjim
08-08-09, 02:45 PM
If I increase the performance of my Northstar- equiped STS I will sit in traffic so much faster.

Mine is a daily Get-To-and-Back-From-Work machine on the most crowded set of go-nowhere highways in the south (Dallas-Ft Worth) 20, 30, 75, 35E, 35W, 635, 121, 190, and then there is DOWNTOWN!!!


HEY...I drive those highways every day myself. :) :)
Usually at least 150 miles a day...sometimes more.

I know what you mean about "GO NOWHERE" highways.

Texas Jim

doowap57
08-08-09, 03:16 PM
Upon taking delivery, of my 2005 STS 4.6 V8, the first thing I did
was check everywhere to get a set of headers for it. I hit every major manufacturer
of Hedders, and got no where, I even hit Advance auto, and explained
what I have done so far, they were very enthousiastic, but nothing.
I had a street machine I had built up, and later added
Hedman Tuned Hedders,WOW, what a difference, not just in performance,
but in between gears, the RPM's didn't go drop as fast.
I was VERY dissappointed that I can't put after market Hedders on my
Cad ! CARB approved of course, that means they have ALL the bosses
for Oxygen sensors, and any other sensors that may be needed for
Emmissions inspections. I would imagine 20 to 25 HP increase with just
this change. Just my 2 cents.

EChas3
08-08-09, 07:33 PM
The Cats are in the headers. With only around 100,000 cars on the road and many left stock, there just isn't that big an aftermarket.

If you're building a track or show car, you have a few options.

K STS
08-08-09, 09:09 PM
oh god... I used to live in Denton. 35 and 121 own my life. Hate 35w and 121 so much.