Another tuning thread...

[Nikolai]

I talked with Allen Nelson, who owns Nelson Performance the other day. He's HUGE on the LSx boards, and I have been down there numerous times to let him do his magic. I asked about tuning for the Caddies and he told me UNTILL THERE IS ENOUGH INTEREST IN THEM he won't do anything about it. I told him there is a huge audience here awaiting something, but I don't think any of us are doing anything about it. Sitting here and waiting for XMS to deliver is getting old.

Can we start a list of those willing to pay for tunes? Allen is gold with tuning, we just need to show enough interest in it. I imagine the cost would be anywhere between $300 and $500.

[acklac7]

What HP gain are we talking about? 30? 50?...Somehow I remember something about the N* being able to handle additional HP..but the 4T80e was "maxed out" at 300hp...And would need to be over-hauled in order to handle 300+...Could be wrong.

[Nikolai]

What HP gain are we talking about? 30? 50?...Somehow I remember something about the N* being able to handle additional HP..but the 4T80e was "maxed out" at 300hp...And would need to be over-hauled in order to handle 300+...Could be wrong.

Everything I have read and heard about says that the 4T80E is bullit proof to 400hp/400ftlbs. I would estimate 30 HP, 30 ftlbs easily with a tune. He can also firm up the shift points as well. If you read over the supercharger project, you'll see they were more than confident it would take it.

[BodybyFisher]

$300 to $500? try thousands and thousands.. It will cost you more than $500 for CAI and a high performance muffler system. By the way stomping on a caddyinfo sponsor (XMS) shows a lack of class.

Do two things, do a search on Mark 99STS and see what he is doing, learn what the limitations are and see how much he is spending and see this site, if you have DEEP pockets you can do a lot: http://www.chrfab.com/

See this also

http://www.hotrod.com/techarticles/engine/113_0303_north/

[JasonA]

What is this guy's idea of a "tune"? Installing Bosch spark plugs?? He's not going to be able to do anything substantial for 500 bucks on these engines. If he can provide a line item list of what services are included in these "tunes", perhaps he might have some response. He won't get any by simply seeing if anyone wants a tune. Our cars are already tuned just fine.

[Nikolai]

$300 to $500? try thousands and thousands.. It will cost you more than $500 for CAI and a high performance muffler system. By the way stomping on a caddyinfo sponsor (XMS) shows a lack of class.

Do two things, do a search on Mark 99STS and see what he is doing, learn what the limitations are and see how much he is spending and see this site, if you have DEEP pockets you can do a lot: http://www.chrfab.com/

See this also

http://www.hotrod.com/techarticles/engine/113_0303_north/

Thousands and thousands? I'm talking about a simple computer tune. I'm not talking cams and porting here. I'm mearly speaking of a computer tune.

I don't think I was stomping on anyone. I appreciate what they've done so far but I'm tired of not being able to do anything more than a throttle body and a cat back.

Yeah, you have to have deep pockets if you have no creativity or inginuity. I guess that's just this boards way. Whatever, I'm not paying $10k for a turbo app when I can build one for $1k. Just seeking a little friendly competition as there is NONE here.

[OynxSTS]

Here we go again.

Nikolai, while I do agree with your point and I think that GM missed a huge opportunity not working with or strongly encouraging the aftermarket's involvement with the Northstar (unlike what they did... off the record... with the TPIs, LTx and LSx small blocks) Computer chips alone are not what these engines need. To get any more out of them you need to look at better exhaust systems, followed by Cam swaps and/or forced induction systems. All of these are big bucks... Even for "easy engines" like the SB Chevys, forced induction kits, with a re-programed ECU, start over $3,000.

The Aftermarket and GM has the option that most of us are geezers who don't like performance cars and who would modify an expensive brand new front wheel drive car anyway...

They should look at my neighbours ES300.... or the TL that lives down the block...

Saddly, there is little (zero actually) chance this will change.

[JasonA]

Nikolai, if your friend can actually modify the OBD-II computer on the 1996+ cars, he should go subcontract for X-M-S and they'd get that project off the ground. The whole reason it's stalled out is because they can't work with the computer, and GM is not working with aftermarket companies on these computers (like they are with other small block GM applications).

I'm sure your friend has good intentions, but just because he can put a chip in an LS1 engine (or even program its computer), that doesn't mean he can have his way with a Northstar computer, which is ENTIRELY different from his familiar C5 and Camaro CPUs.

If you want to make real progress here, have your friend experiment on your car and see what he can do. I don't think you can expect anyone out of the blue to volunteer a few hundred dollars and their car to a guy who can program LS1 computers to see what he can do with Northstars. We already KNOW that simple computer tunes aren't going to help.

You said you're tired of being able to only do a throttle body and catback, but then dismiss the idea of cams and porting. Guess what? That's the next step. Computer "tuning" isn't going to net you more than a few horsepower at the most on these things. 300 hp out of only 281 cubic inches of displacement is already humming pretty good. A guy in the aftermarket isn't going to do much better than GM's engineers who have been developing Northstar electronics for over a DECADE now. If you've already done a throttle body and exhaust and are looking for more, the next step is either custom camshafts or a custom turbo.

You say that you're not stomping on anyone, then proceed to imply that no creativity or ingenuity is just "this board's way". We've been around for a while. We don't choose to be sticks in the mud, if that's what we appear to be to you. If chips and temperature sensor resistors really did something for these cars, we'd be praising their names. We're not negative on this issue because we're not creative. We're negative because we know that chips and computer "tunes" are like chasing your tail, and your money would be better spent, if you're serious about performance, on custom cams and performance torque converters, like a few of our members have indeed pursued, and have found to provide an excellent performance gain.

Best regards,

[BodybyFisher]

"Yeah, you have to have deep pockets if you have no creativity or inginuity", What a POMPOUS statement that is...

along with, "Its not this boards way"... what a laugh! I love guys like you, 12 posts and you come in here like a pric* shooting your know it all mouth off, like we are a bunch of HICKS.

Listen, we have been around the block with this engine pal, and for your information we had a designer of the NORTHSTAR here and as he said, "all of the LOW HANGING fruit has been PICKED"! The only thing that can get a LITTLE more out of these engines WITHOUT spending a BUNDLE is CAI and exhaust... SORRY... IT WILL cost a LOT to get more out of the engine, BELIEVE THAT...Keep in mind that at 300 HP this engine is putting out OVER ONE HP per cubic inch already!

I told you to see what MARK 99STS is doing. I had the pleasure of speaking with him one afternoon and he opened my eyes as to how TIED IN the computer is to this ENGINE.. He is in the process of interfacing a PIGGY BACK computer to fool the existing system. Seek him out, I will send him a note and have him stop in and tell us what he has done and how difficult it is to deal with the existing computer. GM has NOT allowed this computer to be hacked, developed, or modified very easily, and I am sure its for good reason. YOU will NOT easily do a COMPUTER "TUNE" on THIS engine.

As far as stomping on people, that is exactly what you did. This is NOT a "free for all" forum like some others out there where they disrespect each other. I would advise that you visit www.cadillacforums.com its a good board but there is much more discussion about TUNING, and it will fit your attitude a little better.

As a matter of fact, there was a guy over there who "TUNED" his CTS-V, over-revved it, and BLEW it, that thread is GONE now but you can see the discussion here:

http://caddyinfo.ipbhost.com/index.php?sho...&hl=K&N

[Regis]

Thousands and thousands? I'm talking about a simple computer tune. I'm not talking cams and porting here. I'm mearly speaking of a computer tune.

I don't think I was stomping on anyone. I appreciate what they've done so far but I'm tired of not being able to do anything more than a throttle body and a cat back.

Yeah, you have to have deep pockets if you have no creativity or inginuity. I guess that's just this boards way. Whatever, I'm not paying $10k for a turbo app when I can build one for $1k. Just seeking a little friendly competition as there is NONE here.

For someone who apparently just joined the board this November 23rd you've got king kong balls and a whole lot of *smurf* to go with it or you're really just Nicky (Bonnett) playing games once again.

[BodybyFisher]

I just can not help associating Nikolai and Nicky for some reason, maybe its the attacks

[BodybyFisher]

YOU will NOT easily do a COMPUTER "TUNE" on THIS engine.

I need to clarify that statement. Companies such as http://www.chrfab.com/ utilize a proprietary or aftermarket computer system in their high performance builds, below is a typical "system". See this statement:

VVT (Variable Valve Timing) controlled by the Magneti Marelli computer, hydrolically actuated cam phasers on all four camshafts for maximized performance.

Well that is fine and dandy if you want to put that entire system in some high performance chassis, but if you put this into a Cadillac, ohhhh the engine would run terrific, BUT....... NOTHING else would!

Unlike Chevrolet and other manufactures who have allowed an open system whereby a chip can be installed or the existing parameters can be changed, GM/Cadillac from what I understand have intentionally created a closed system to discourage changes. From my discussions with Mark, the existing system seems to detect changes and react to stop changes that could potentially cause damage. Pretty innovative thinking if you ask me to give the system the ability to protect itself.

I have ridden in the 68 Corvette 427 cu in 435 horsepower car along with a few old school HEMI's, that would break your neck. When I was I kid, I used to be amazed that chevy was able to produce more than one HP per cubic inch. This Northstar at 279 cu in, is putting out 300 horsepower on regular gas, with low emissions with an engine that weighs half as much as a 427. I have heard it said, that basically, an engine is an air pump. There comes a point where, the size of valves themselves and the duration they are open can no longer pass more AIR and the engine is topped out. Changing to CAI, maybe changing the TB and opening the exhaust helps, but to get big gains porting, putting in larger valves and changing the CAM, injectors......how far do you want to go... But then, when you do all of this work, have you caused the engine to be less fuel efficient, more polluting, less driveable or less dependable?

Take another gander at this page, this is where you need to go to produce more power, 360 horsepower for $4,500!

360 horse power

10.5:1 compression ratio

Forged steel crankshaft

VVT (Variable Valve Timing) controlled by the Magneti Marelli computer, hydrolically actuated cam phasers on all four camshafts for maximized performance.

Electronic throttle control, no hard to route cables, integrates idle control. TPS sensor is all that is required at the gas peddle.

Piston skirts are polymer coated

Larger piston pins

Front mounted water pump

$4,500.00

[Nikolai]

Hey, get a grip. I was just making conversation and you flip out. I'm just here to get information and interact. If you can't handle even the slightest bit of negativity, perhaps I should just leave.

Sorry to spill your milk old man.

[BodybyFisher]

Hey, get a grip. I was just making conversation and you flip out. I'm just here to get information and interact. If you can't handle even the slightest bit of negativity, perhaps I should just leave.

Sorry to spill your milk old man.

Like I said, you sound more like Nicky with every post

[Bruce Nunnally]

In an attempt to get this thread back on topic, yes it would be great if we saw more tuners or products for Cadillacs that were inexpensive and effective. That is a perfectly good question/discussion topic here and you are welcome to explore it.

So far the only time you DO see that is when as in the case of the Escalade Cadillac uses a chevy engine like the LS1 which already has tuning items developed for it. The same applied when the Fleetwood used the LT1; you could get nice mods for it.

The problem with tuning the computer in the Northstar is that Cadillac/GM have put additional security codes or checksums in the computer to help protect proprietary engine management the Northstars have that regular LS1's for example don't. A specific example is the limp-home running cool with no coolant mode. So although Tuners *think* that because they have good experience with other GM products they can also retune the Northstar computer, no one has been successful at it yet, or at least not since 96. XMS did not try to reprogram the PCM themselves; they tried to pay anyone to do it, and although several promised products no one delivered. CHRFab uses a separate aftermarket PCM instead, which is great for sandrails but would mean severe compromises in a production Cadillac.

[stlthbmr]

Hi All,

Since were on the topic of tuning. I have got to pull my N* to do a timesert/head gasket job. I was considering doing some head port clean up and slightly enlarge (couple of thous.) the exhaust ports. Really nothing more than a cleanup and smoothing of the casting. Will this in anyones opinion have a positive or negative outcome. And has anyone attempted to fabricate headers, or run a true dual exhaust? I have waited a long time to consider any mods to my 96 STS, but he's getting a little older and needs a little extra attention right now.

Thanks

Joe

[MARK 99STS]

Okay guys here is the scoop. You can't. I repeat CAN'T tune the OBDII computers unless you use an after market piggyback computer like I put on(see my previous posts). Then the only thing you can control is the fuel by skewing the MAF signal. These computers cannot be reprogrammed or reflashed like the OBDI. There is no chip for the OBDII. It is worthless to change the fuel trim unless you plan on pumping more air into the motor like a supercharger or turbo. This guy may know a lot about tuning, but he dosen't jack about these Cadillac computers. Sorry, just speaking from experience.

I have owned my STS since 2001 and have been a member of this and the previous board since that time and have been trying to find ways to increase power ever since. Some things have been a waste of money and others have produced good results. Until just recently I didn't think I would ever find a way to supercharge or turbo these cars since the XMS project died.

I am about a week away from completing the long awaited turbo project. This has been an extreme undertaking and it is not going to be cheap, but as we speak it looks like everything is going as planned.

Unless you want to go this route the best bang for your buck is a cold air induction working in conjunction with an open exhaust. For off the line add a high stall torque converter. Other than these items the rest is a waste of money.

Sorry to step on anybody's toes here, but I have been there and done all this and I am speaking from experience not hype or heresay. I know there is a lot of talk about the bigger TB on the other board, but it is not ging to do any good unless you can pump more air IF you already have an open exhaust and open intake.

Not just my opinion, but my actual experience.

[stlthbmr]

Hey Mark,

It's obvious, (to me anyhow) that we can't "tune" the computer. I had no plans to modify the computer. What I wanted to know is since I'll already have the heads off the engine, would it be worth my time by cleaning and smoothing up the ports and opening the exhaust a couple of thousands. This along with a less restrictive exhaust system, It was my thought that it would help the engine breath a little better. I'm a retired welding engineer with lots of time and material and eqipment on my hands. It really won't be anything out of ordinary for me to fab up a set of custom headers and exhaust for my ride. If I wanted to do anything more than what I was just talking about, I'd Just buy me another Seville and pro street the thing. Anyway I understand your annoyance with the same questions on the "Quick" tune. Nothing that is worth doing is ever easy. I for one appreciate the Hi-Perf. R&D that you are doing. I'm new to the site but I learn something here every day.

Thanks,

Joe

[danbuc]

I'm a retired welding engineer with lots of time and material and eqipment on my hands. It really won't be anything out of ordinary for me to fab up a set of custom headers and exhaust for my ride.

It's darn near inpossible because of the space, but if you could find a way to increase the diamet of the crossover pipe from the left bank manifold, that would help performance. It's the single biggest restriction in the exhaust system, and does reduce the engine ability to breath by quite a bit. The problem is routing a larger pipe through there. If you could fab up a set of custom header, and find a way to increase the size fo the crosover pipe, there's plenty of people here that would be interested. That crossover it the main reason nobody bothers with making custom headers, since there's not much to really be gained unless you mess with that crossover pipe. It's flattens itself out and snakes between the oil pan, and tranny case to the back of the engine compartment, A really tight squeeze. Since you said your an experienced welder with plenty of material, if I were you, that would be my number one problem to tackle. Once the crossover pipe size is increased, then headers will really make a big difference. In the meantime, and free flowing catback is the next best thing, and will increase performance a little bit.

On a side note, Mark, I was wondering where the turbo will be mounted. Are you fitting it down by the junction point where the crossover meets the right bank manifold, or further up inside the engine compartment?

[MARK 99STS]

Anyway I understand your annoyance with the same questions on the "Quick" tune. Nothing that is worth doing is ever easy. I for one appreciate the Hi-Perf. R&D that you are doing. I'm new to the site but I learn something here every day.

Thanks,

Joe

Hi Joe and welcome aboard. It's not so much that I'm annoyed at the question, but more of just stating the facts. Sorry if I came across to harsh.

It is as Danbuck said. The choke point of this motor is the smashed crossover pipe. Until you can reduce the restriction;headers, porting the heads,etc won't do a whole lot. I had the exhaust side of the heads ported and it had no increase at all because of the crossover pipe. Putting on an open exhaust would be your best bet. These cars dyno at about 216hp at the wheels stock. I'm at 250hp per the dyno. That is maxed out unless you go forced induction. Unfortunately the only place to run the exhaust is under the cradle. We are using some oval pipe along with standard stainless.

Danbuc,

The turbo is mounted in the left front fenderwell behind the head lights. We had to do some serious cutting and modifications to make it work, but we got it in there. I'll have a bunch of pictures and comments on my site a little later. Right now I'm bustin it to get it finished. We just finished the oil feed and return lines tonight. God is it tight, but we got them run.

[attachmentid=2238]

[BodybyFisher]

Thanks guys for stating the facts, limitations and difficulties in sqeezing more performance out of this engine. I had been trying to say this from the beginning that $500 is a drop in the bucket and that its not a simple chip 'tune' like we see on shadetree mechanic, truck universe and two guys garage on cable tv.

If we could find someone to do it, what would custom headers cost? Do headers change the under hood heat level? I can only imagine that having a pipe below the carriage would make it a target for damage from it being so low? Plus the ugly visual look of the low pipe.

This company produces headers for the CTS-V LS*

http://www.kookscustomheaders.com/product_...egType=Cadillac

[justgreat]

Thanks guys for stating the facts, limitations and difficulties in sqeezing more performance out of this engine. I had been trying to say this from the beginning that $500 is a drop in the bucket and that its not a simple chip 'tune' like we see on shadetree mechanic, truck universe and two guys garage on cable tv.

If we could find someone to do it, what would custom headers cost? Do headers change the under hood heat level? I can only imagine that having a pipe below the carriage would make it a target for damage from it being so low? Plus the ugly visual look of the low pipe.

This company produces headers for the CTS-V LS*

http://www.kookscustomheaders.com/product_...egType=Cadillac

i recall this discussion many moons ago with the bbb...the headers are a real challenge due to the fwd layout. lots of compromises had to be made for fitment reasons. one sure fire, guaranteed investment in power mods that are universal to all engines are cleaning up the intake and exhaust ports,; in addition to head work. having the head and c/c flow tested will definitely help with the output numbers...whether the increase would be so dramatic as it would with a small block ohv is another matter. with ohc engines and pentroof heads it's pretty hard to make improvements over the original design. one area that can help is removing any obstructions in the intake runners or the exhaust ports and exhaust headers...but something tells me that with modern manufacturing and casting techniques not much gets by the production engineers.

jackg 90seville 99k

[MARK 99STS]

Mike,

Your right that this is the draw back as my pipes are low and exposed. We are working on some options to overcome this but you have no choice, especialy from the front bank. It is so tight under there, there is absolutely no where to run it except looped right under the cradle. It is unfortunate, but I am willing to do it to get the turbo. As has been stated before, it is all about compromises.

[MARK 99STS]

having the head and c/c flow tested will definitely help with the output numbers...

Jack,

You are right that there is a lot of room for improvement on the flow. I had the exhaust only(as recommended by an expert)of the heads ported. The flow test showed an increase of 22-24 cfm. The guy at the performance shop was amazed to see that kind of increase just by doing the exhaust, but he also told me I would see none of it if I didn't open up that crossover pipe and he was right as I saw no gain at all. Im running 2.25" pipe from each bank to the turbo and 3" exhaust off the turbo so I should have some SERIOUS flow. It should be interesting.

[stlthbmr]

Hi All,

I'd like to thank everyone for getting me on the right track with my Seville. I spent about 6 hours reading past posts and links relating to the N*, and about 2 hours under the car. What an eyeopener. I now feel pretty embarrased of how little I knew about a car I've been driving for the past 9 years.

I guess I enjoyed the power, luxury and the smooth operation so much I didn't really give a hoot about the nuts and bolts of how it was accomplished. I just drove the tires off it. After reading all the tech articles on this motor I am amazed at it's stock output and the computer integration of all the systems that make up the "package".

Being a hotrod/performance enthusist I've built many rods and customs. Of course they all used the typical powerplant/tranny combos and no ECU's. Now that it's time to do some work on the STS, I have gotten excited about the capabilities of the N*.

I do apologize to those of you who have been around the block whith the ins and outs of these cars for my ignorance on a couple of my earlier posts. Thanks for your patience during my break in period concerning both the modification of these cars systems, and to the site.

I can truly say I'm getting hooked.

Thanks,

Joe