My First Scan, 14.9* of KR

[mattpietroski]

Where should I start? Scan attached! This is my first scan, I am new at this, so please take that into consideration, and I understand that I need to fix things one at a time. Thank You for any help that you can provide.

The car is a 1999 GTP. the only mods that it has is a 3.4" pulley, and one heat range colder plugs. I know the 3.4 is too small with no other mods, but I plan to do the supporting mods sometime in the near future. I would like to get the tune a little bit better for now.

[Bill@HPTuners]

that is a configuration file not a .hpl scanner log. Without an .hpl scanner log we cannot see what you're seeing.

[z34phoenix]

even without seeing the scan i can tell you you are lean, and prob runing too much timing LOL


too much boost and not enough mods is a recipe for a blown up motor.

please do not run that car in boost until you either go back to the stock pulley or drop 5* of timing and enrichen AF by atleast .5 to .7 to start with.

im not that familier with HPtuners but if you have a intake air temp VS spark table use that to pull the timing... just adjust the bottom half for each air temp value.


and then use the PE AF to lower the AF value.. if it was 12.4 before make it 12 or 11.8 or something to that extent. then scan again and watch for KR.

chances are your fuel trims are way out of where they should be too. Do a MAF tune to get things dialed in.


In the mean time.. get a Cold air intake on the car, and get the Ubend removed. drop in a 180* thermostat

[Shazbot]

Get that pulley off there or at LEAST do NOT enter boost! You are in danger of destroying your engine, your support mods must be done FIRST before you drop pulleys!

People argue about the actual mods required before running a 3.4 pulley but the general consensus says you need at minimum a CAI/FWI, PCM/Tune, downpipe/or Ubend del., colder plugs, 180 tstat. If you look at my sig and see the mods I am running I am getting 5-7* of KR at WOT during winter. Many people even recommend installing headers or torqueing down a set of rockers.

In all seriousness my friend, a 3.4 on your near bone stock car is detrimental to your cars performance and your engine's safety. Your doing yourself, your pocketbook and your car a favor if you refrain from running a 3.4 or boost at this point in time.

If I were you, I would place priority on support mods before I even began any real tuning.

[85DropTopTA]

Where should I start? Scan attached! This is my first scan, I am new at this, so please take that into consideration, and I understand that I need to fix things one at a time. Thank You for any help that you can provide.

The car is a 1999 GTP. the only mods that it has is a 3.4" pulley, and one heat range colder plugs. I know the 3.4 is too small with no other mods, but I plan to do the supporting mods sometime in the near future. I would like to get the tune a little bit better for now.

i believe on a 99 GTP 14.9 is the limit for how much timing your tune will pull stock.

you could be seeing way more spark knock then that but your computer is doing the most it possibly can to save your motor.

[JerryH]

Getting a 3.4 to run on a basically stock 199 GTP is very possible. I dropped 0.4 second doing nothing but a 3.4 pulley.

However... as time goes on, there are things that make it harder. As an example of one of the possibilities, a stock catalytic converter is basically one nice plug after 50,000 miles. What are the boost pressures you are seeing? MAP(kPa) will also tell you. If you are seeing around 9 PSI of boost in warm temps (70-90F), thats normal. However if you are seeing 12 PSI, thats a clear indicated of boost stacking caused by a plugged cat.

When was the last time the fuel filter was replaced? They plug up too, not permitting all the fuel to get to the engine under higher loads.

When was the last time that the airfilter was cleaned or replaced? The MAF and IAT also need cleaning too.

I always advocate making sure that the car is 100% mechanically sound BEFORE modding or tuning it.

For now, I suggest that you go to a 100% stock bin for the time being, get the car mechanically sound and only then scan and see where you are. Stay out of the throttle until then, yes?

[Shazbot]

Getting a 3.4 to run on a basically stock 199 GTP is very possible.

Advocating running a 3.4 on just a tune is logic based on a shaky foundation(no mods holding it up). I agree that the engine needs to be mechanically sound but the engine needs to be modified to support a drop in pulley size. There are an army of people that would argue tune vs. mods for a 3.4. The tune is only part of the equation, it cannot supplement all of which the support mods would be offering to support the 3.4.

Tuning for a 3.4 on a near bone stock car just seems to be wasteful, I would only look at it as a temporary solution until the support mods are in place. There is no way a tune is going to adequately deal with the huge KR as described, please correct me if I am wrong.

I would like to know what you are thinking in terms of dealing with the KR though.

[Perforator]

Obviously there is something wrong if he's getting 14.9KR. That is not normal even on a stock car with a 3.4 pulley.

[Shazbot]

However if you are seeing 12 PSI, thats a clear indicated of boost stacking caused by a plugged cat.

With my current mods I would easily hit 11.5 - 12 PSI going WOT. I would even hit 14psi when I did a 3-1 downshift going into WOT... My cat is a magnaflow and that was barely 6 months old.

I am not saying your wrong by any means, just that I can easily replicate that PSI on my car as it is which is more modified than Matt's car.

[mattpietroski]

Here is a new scan, I realize that I saved the file wrong in the last one. Sorry it took so long, I was having some issues figuring out the data logging. I only saw half as much knock on this run. The first run it was 7* outside. This run it was 52* outside. I was not aware outside air temp could make this much of a difference. Can anyone explain? As of right now it is a completely stock tune.

Thank You

[JerryH]

Advocating running a 3.4 on just a tune is logic based on a shaky foundation(no mods holding it up).

On what do you base that comment? I base my comments after tuning 7-8 totally stock GTPs and 2 L67 Fieros with basically 100% stock engines and a 3.4 (exhaust and CAI not withstanding on the Fieros).

All ran between .3 to .7 seconds faster (the Fieros were low 13 second machines with nothing else!), all had under 1 degree of KR at worst, no speed limiters and in the case of the GTPs, all had a MPG increase of at least 2-4 MPG. I did not do any MPG comparisons before on the Fieros, so canot tell what if any improvements there were, but owners reported increases.

Also think about it... how many 100% stock GTPs beween 1997 to 2002 ran around for the longest of times with nothing done to their cars except 3.4s? A lot more than one would suspect. Is it ideal? No, but a good tune does make a huge difference and does allow you to SAFELY and reliably run a 3.4 all day long with nothing else.

The biggest factor always was mechnical condition before doing the mod.

[JerryH]

Here is a new scan, I realize that I saved the file wrong in the last one. Sorry it took so long, I was having some issues figuring out the data logging. I only saw half as much knock on this run. The first run it was 7* outside. This run it was 52* outside. I was not aware outside air temp could make this much of a difference. Can anyone explain? As of right now it is a completely stock tune.

Hotter air usually results in more KR. If you are telling me that at an outdoor temp of 7 degrees you had 14.5 degrees of KR, then went back to a stock tune and wanrmer temps (52 degrees) gave you less KR, my first thought is that the tune was in desperate need of help. Please correct me if I mixed things up... lol.

Let me look at your tune and get back.

Also, can you answer me the following questions, please:
- last time plugs were changed?
- last time fuel filter changed?
- mileage of car?
- original catalytic converter?
- last time air filter changed?

Thanks.

[Shazbot]

On what do you base that comment? I base my comments after tuning 7-8 totally stock GTPs and 2 L67 Fieros with basically 100% stock engines and a 3.4 (exhaust and CAI not withstanding on the Fieros).

I base that comment on a couple things. 6 months of research, hours and hours spent reading everyday and not even the slightest memory of ANYONE saying a 3.4 and a good tune is enough(mostly research on ClubGP). When I say research I mean studying upgrades and their effects' on our car. I have no doubt of your knowledge and skill in tuning, but it is dangerous to press tuning as an alternative for mods in terms of pulley drops. What level do you expect someone to be at, to be able to tune a stock GTP to run a 3.4? Surely most people out there will not try, briefing over the L67/L32 engine forum at CLubGP reinforces this.

Also think about it... how many 100% stock GTPs beween 1997 to 2002 ran around for the longest of times with nothing done to their cars except 3.4s? A lot more than one would suspect. Is it ideal? No, but a good tune does make a huge difference and does allow you to SAFELY and reliably run a 3.4 all day long with nothing else.

Unfortunately too many, however we can look back from 2008 and see just how far the market/knowledge and the GTP have come. The failings/shortsight of modders before us cannot be used to justify dangerous methods of performance enhancement now, the infancy of the market and naive innocence in upgrades should not be used to justify it. I still stand by support mods as the framework for which tuning builds on. Due to lack of hard facts and stats, we are not able to comprehend the damages and costs involved in the market drowning itself in 3.4s back in the day. My absence from modding during that period of time prevents me from speculating further.

[JerryH]

Ok, a few comments...

First off (don't laugh now), this is the first time I am looking at a L67 scan with the intention of looking for issues using the HPT program (is a way to output a CSV file to look at? I can whiz through a 20 minute scan a LOT faster and find all the "issue" points effortlessly). Looks like I am going to need some practice with this way of doing things, perhaps.

- Highest MAP(kPa) that I saw was 173, which is about 10.73 PSI. At 52 degrees outdoor temps, this is about 0.75 - 1.2 PSI too high (on average). So there is obviously some blockage in the exhaust. A full 3" ID downpipe and new cat would definately be of some help to you.

- O2s at WOT were 911 or so. You want to get the O2s up higher to around 940-945. Your Base PE can be lowered to something like 11.7, but that alone won't get you up into the 940's, raise your MAF table in the 7000-11500hz range until you get the fuel curve needed to get you there.

- your trims were not locking in at 0 in PE. A few MAF tunes will address that.

- your PE enable point should be set to between 28-30% TP

- you will likely need to increase your AE somewhere between 10-15% higher, but start off from stock and do baby steps. AE MPH modifier should be all set to 1's across the board.

- Do not touch the timing tables yet. As a general rule, I do not advocate lowering timing lower than stock.

Before doing any of the above...
- disable any and all tables setting that disables injectors
- set your speed limiters to 255 MPH
- address any torque management tables (in the fuel and spark areas) that lean out fuel as a form of torque management and set them to 11.7

Here is the fun part... ONE CHANGE, ONE SCAN until you are comfortable with your car and the tuner and know the effects of any change that you make.

That should get you through a "level 1" stage of the tune.

[Shazbot]

Hotter air usually results in more KR. If you are telling me that at an outdoor temp of 7 degrees you had 14.5 degrees of KR, then went back to a stock tune and wanrmer temps (52 degrees) gave you less KR, my first thought is that the tune was in desperate need of help. Please correct me if I mixed things up... lol.

Possibly but not necessarily, colder air = denser air = more boost potential. If he picked up 1-2 more PSI, that could easily relate to more KR. a 45* difference in temperature does not seem too far fetched in offering a partial explanation for the differences in KR. There really needs to be a good solid discussion -with evidence on the effects of colder air on our cars. When I scanned in the summer of 2007 I had 4-6* of KR. When I scanned during a WOT run with the ambient temperature of 19 I had 7 - 9* of KR.

Are we allowed to link to other sites? I have a fistful of links that somewhat address this issue and offer some insight into how colder air affects our cars.

[Perforator]

is a way to output a CSV file to look at? .

Jerry, click on the little green left arrow right next to the centigrade/farenheit thing. I do the same thing. I gotta see each frame...

[JerryH]

...it is dangerous to press tuning as an alternative for mods in terms of pulley drops. What level do you expect someone to be at, to be able to tune a stock GTP to run a 3.4?

My absence from modding during that period of time prevents me from speculating further.

If a car is in good mechanical condition, going to a 3.5-3.4 pulley without ANY tuning resulted in a faster 1/4 mile time. I am not advocating going to anything smaller, and in the case of using a 3.4 on a high mileage car in poor condition will result in poor results. That is why I am always asking about car condition.

I've been around the GTP scene since 1998, so I do not say it just like that. it has been done hundreds if not thousands of times safely. Heck, Mecham back in 1997 on his Vitesse offered it as optional package WITH a 3.4 on a STOCK PCM (and later was THE first on the market to offer an aftermarket PCM modifications in early 1998) and GM offered the GTX with the full factory warranty and the 3.5 or 3.4 inch pulleys were an option, again on a stock PCM from SLP.

I ran a 3.4 on my otherwise 100% stock car from 4400km on for over a year and hundreds of WOTs without ill effect before I purchased an aftermarket PCM.

Now... make no mistake about it, I AM NOT advocating tuning as a compensation to modding. Mods are good, they take you further than PCM tuning alone can. However, anyone that tries to run anything smaller than a 3.4" pulley on a stock car is a fool and asking for a few chunked pistons.

I know of MANY real life examples where a well tuned basically stock (or lightly modded) car outperforms a heavily modded car with a poor tune. If you doubt my word, ask Foghorn. His 97 with NOTHING more than a CAI and a 3.4 (or 3.5?) Bonnie hung with a poorly tuned bonnie that was more heavily modded, including headers and an aftermarket cam.

I will say it once again, a 3.4 can be made to run well on a basically stock engine as long as the car is mechanically sound and well maintained. I have done it many times as have others.

I would NOT recommend it with anything smaller than a 3.4 pulley.

Look, I am not here to argue. I have made a 3.4 pulley run very well on a more or less stock cars many times in the past. It has been done and can be done. However, to get the best out of any car, it will take more than a tune. There are some VERY basic and cheap mods that I consider "musts" on a GTP. A custom insulated CAI and a downpipe are two that are "musts" for me as a starting point and do draw a lot more out of your car than some can imagine. On a wel tuned car, those 2 mods alone are an easy + 15-25 extra HP and at least 2-4 MPG with a proper tune over a 100% stock car.

[Shazbot]

I believe in equilibrium between tuning and modding. They really do go hand and hand, without each other neither can achieve its highest potential...

[JerryH]

Jerry, click on the little green left arrow right next to the centigrade/farenheit thing. I do the same thing. I gotta see each frame...

lol... aren't we the one schooling me lately!

Thanks I appreciate it!

[JerryH]

I believe in equilibrium between tuning and modding. They really do go hand and hand, without each other neither can achieve its highest potential...

Most definately on this we agree!

However, the user is not highly modded, and his choice of a first mod does change things enough that a good tune will help him run that pulley safely... its not so drastic that it is outside the possibilities of making it run well on just that pulley and a tune alone.

Now if he said he had a 3.25, I would say.. either take it off, remove the electrical connector on the BBV or stick a block of wood under the pedal, until he has more supporting mods, because if not, he is purchasing a few new pistons real soon... lol