Advice on Dyno-Tuning S/C

SYNFULL

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I am still trying to get the bugs worked out of my Roe Heads and S/C install. I am using the basic tune that Sean sent me and the car runs pretty good but has some issues. Namely a chirping noise that I have posted about. http://forums.viperclub.org/rt-10-gts-discussions/613587-supercharger-chirping-noise-problem.html I think it is detonation but Octane Booster didn't help. I also tried taking some timing out (where it was 12.5 degrees I lowered it to 12.1) and that may have made it a little better. It happens mostly in second gear when you load up the motor.
I have spoken to quite a few people about it- Sean Roe, Tony Armour and 3 mechanics that I have taken for rides. Naturally Sean and Tony are just going by my description and my log files so it's kind of tough to diagnose from long distance. I have redone the T&D rockers to make sure there are no issues there. I also did compression test on the cylinders and here are the results
#2 - 180
# 4 - 180
# 6 - 180
# 8 - 190
#10 - 175

#1- 170
#3 - 170
#5 - 165
#7 - 190
#9 - 190
Looks like cylinder 5 might be a little low- I am going to retest. Seems like the battery was getting weaker there and may have made a difference.

In the meantime I have booked an appointment at a shop that has a Dynojet Dyno for Monday. First they are going to try and diagnose the chirping sound. Then they are going to Dyno it. What would anyone's advice be on tuning the car while it's at the Dyno shop? Should I fax Sean the results and have him email me the changes so I can have them do another run to see if it's right? Naturally this assumes that there are no severe mechanical problems anywhere causing this sound that I am hearing.

Thanks
Gary
 

plumcrazy

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i think that #5 is fine. its too small of a difference from what i was told to worry about.
 

Joseph Dell

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to add to what Tony is implying, octant boost adds .1 or .2 of octane... so a bottle when you have a tank of 93 bumps your octane to a whopping 93.1 . race gas (110 octane or so) or even 100 octane unleaded would help you see if it is detonation or not.

good luck!

JD
 

RTTTTed

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"General rule of thumb" on a compression test is 10% so your test is borderline. Yes, if the engine was turning over slower you'd get a lower reading. Normally if the difference is 10% it would be one side of the engine lower than the other side indicating wear. Problems usually make a big difference in the compression, no a small one like yours.

It may be an incorrect reading, or indicate a 'small' problem. After a base line compression test you could do a second test but add a couple drops of oil into each cylinder and spin the engine once or twice ... then retest. If the compression goes up that indicates rings (unless the gain is equal on all cylinders like it should show). If the low compression reading stays the same, that would indicate a valve problem.

Ted
 
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SYNFULL

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I haven't had much luck finding racing gas around here. Anyhow the car is going to the dyno shop tomorrow. Any advice on how to proceed with getting it tuned? I have never had it dynoed before.

I also have a question on wideband setup. I want to install at least on 1 side but I am a little confused on what I read. I have been having some issues with idle hang and read that the 02 sensors should be moved to the collector area of the Belangers. I also read some replace the 02's with "quick start 02's"? from dc performance. If the 02's are moved to the collector area are the wideband 02's also placed in that area? Keep in mind that I have no cats.

Thanks
Gary
 

Mr Hemi Head

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Synfull I tried tuning my Roe on a Dynojet twice with mixed results..it does not load the engine like street driving.

This was a good start for a baseline tune but the final tuning was done on a closed course. This requires an aftermarket A/F monitor and VEC software.

My O2 isensor is at the collector on the drivers side.

The dyno is a great place to diagnose engine noises since you can hear stuff that cannot be heard in the drivers seat.

I would not spend a lot of $$$ on dynotime unless Sean is available to read the files.
 

RTTTTed

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Where you place the O2 sensor should depend on what the instructions say. Most are made for stock locations, but different applications mean different locations.

Ted
 

Schulmann

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My advise is short and simple:
I would invest my money into two good WBO like Innovate. Once you have these tools connected to the VEC you will wonder how you was able to live without them.

Dyno tuning is too off from what you experience on street/track with the Roe supercharger. Though it is a good method to double check the accuracy of your Innovate setup. For instance you might be lean and this is what causes the the knocking.

If you think that you have knocking, retard the ignition by 5-6 degrees that should immediately stop knocking issues (Or add fuel).

You can also you a infra rayed temperature tool to check the headers' temperature. A More warmer header usually runs lean. Espetially the front cylinders are tendency to run leaner.

Race gas is a waist of money and time but well it is another way to fix your problems. You have to setup ignition for the fuel that you will use and buy on daily basis. It is very very easy to tune the VEC if you have the two WBO. Usually it takes less then 30 sec to fix this type of issue for those who have the right setup.

Regarding the compression test : it is difficult to have consistent readings. I would rather focus on leakdown test. It takes only 90 minutes to perform it on a Viper on all 10 cylinders. My leak down was 8% on all cylinder except on #4 where I read 14% at 30000mi.

The real difficulty is to gain 30-40hp with a given setup while tuning fuel and ignition accross all the rpm and load ranges.

Have fun and take your time to tune right your Viper ! We are likely the most lucky guys in the tuning world having the VEC to tune our engin ....
 
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SYNFULL

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I am just reading up on the widebands now. It is kind of tough learning the tuning part from scratch just by reading posts in the forum. I wish there was a class I could take:rolleyes:

Thanks
 
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SYNFULL

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Can I install the wideband sensors in the rear 02 location. I don't have any cats and I am not using the rear 02's as I have 02 simms

Thanks
Gary
 

1TONY1

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Can I install the wideband sensors in the rear 02 location. I don't have any cats and I am not using the rear 02's as I have 02 simms

Thanks
Gary

Yes you can, make sure there are no exhaust leaks before the o2's.
That said, I would rather see them in the header collector.
 
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SYNFULL

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So, the shop just called me and said it is definetely detonation. My question is- why is my car doing it with a mild tune. If I take out timing to get the detonation to stop- aren't I losing horsepower? Is dynoing the car going to be helpful in any way?

Gary
 

mbccenter

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Your air to fuel will tell you everything you need to know. What has the outside temp been when this is happinging?
 

EllowViper

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With my 5 lb ROE set-up on my 01 creampuff with W/M injection, I'm now able to run only a few degrees of retard from the stock open loop (mostly below 3500 RPM) and actually can run one degree more advance than stock from 4000-5000. Like Schulmann indicated, its all in the fuel and timing balance. It does little good to just work the AFR without grasping how the timing is factoring into the equation. Sean's base tune can only take you so far and each application requires dialing-in. You need to read Sean's tuning instructions to see how it all works together. Before I dug into the timing aspect, I was unknowingly maxing out my injector duty cycle at WOT seeking that magical AFR. Remember at 6000 RPM you only have 21ms of injector duty cycle. When I added the W/M and started working both the fuel and timing equations a bit more deliberately, it all started to come together. Many AFR issues can be addressed simply by timing. A WB is an absolute must. My Innovate LC-1 works just fine.
 

Steve 00RT/10

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I haven't had much luck finding racing gas around here. Anyhow the car is going to the dyno shop tomorrow. Any advice on how to proceed with getting it tuned? I have never had it dynoed before.

I also have a question on wideband setup. I want to install at least on 1 side but I am a little confused on what I read. I have been having some issues with idle hang and read that the 02 sensors should be moved to the collector area of the Belangers. I also read some replace the 02's with "quick start 02's"? from dc performance. If the 02's are moved to the collector area are the wideband 02's also placed in that area? Keep in mind that I have no cats.

Thanks
Gary

The Belanger fix for MILs with cast piston cars was to put a **** in the 3rd tube. From what I gather now, they may not even have an optional **** welded in where it belongs.
It was a band aid solution ... and not the right one. I had one of the early Belanger cast piston/different cam cars and went through some misery with MILs before finding a fix. My Belangers came with the **** in the right place and no other choice (4/01). Later that year -- maybe the following year, they came up with this 3rd tube business. It only makes sense it's not the right place to be........only sensing 1 tube instead of a 5 tube average........the way it came from the factory. (and with our car - moving to the 3rd tube didn't fix the problem at all) You may not need to buy Quick fires for your 99. Some 99s set heater code lights /slow response ---others don't. It would be worth a try with the factory O2s first. I know a guy with a DLM 3+ kit that will set an occassional light on his 99. ....Not enough to worry about. The WB also belongs in this same area. The less chance for error the better. The further back you go the more exhaust joints to get an air leak.

The OEM sensor belongs where it was from the factory -- sensing all 5 tubes. Unless your tuning your car to the ragged edge, one WB is likely enough.

Street logging is the best way to tune the AFR. If you don't use the IAT parameters available in the VEC 3 (or an upgraded VEC 2), you will likely need to tune more than one card. I used to have 3 cards -- 50/70/95F. The high temp end is not as critical as the low temp end......which needs a richer mixture. A card tuned for 45 degrees will just run a little fat at 90F. I now have one card which is working fine from 30F to 100F.

For comparison to your car.. we have a 5 pounder/RR/no W/M/Belanger headers and exhaust/ no cats.

I also broke down and bought the 96 PCM -- solves several little issues -- including the O2 light problem. You need to get a OBDII code reader / eraser. They're cheap. $40 bucks or so. VERY handy for some of this stuff.

Steve
 
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SYNFULL

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Steve,
So, just to be clear, the stock 02 sensors, and the wideband sensor should both be in the collector area of the header?
My car never set a code with the belangers until I installed the S/C. Then it started setting P0138. I installed the 02 simms and that code hasn't reoccurred.
When I asked Dave at Roe about upgrading my vec 2 to a vec 3 he insisted it wasn't necessary and wouldn't be to any advantage as long as I had the latest firmware on my vec. Do I have the features of the vec 3 with new firmware or does this require a physical upgrade of some type.

Thanks
Gary
 

Steve 00RT/10

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Steve,
Thanks
Gary

So, just to be clear, the stock 02 sensors, and the wideband sensor should both be in the collector area of the header? YES

My car never set a code with the belangers until I installed the S/C. Then it started setting P0138. I installed the 02 simms and that code hasn't reoccurred. I have Simms in the back as well. I believe that's a rear heater code so the Simms would take care of that.


When I asked Dave at Roe about upgrading my vec 2 to a vec 3 he insisted it wasn't necessary and wouldn't be to any advantage as long as I had the latest firmware on my vec. Do I have the features of the vec 3 with new firmware or does this require a physical upgrade of some type. I don' think this is quite right. There are 3 things I know of that an upgrade will do: log HP, log Torque, fix the multiple card issue with the new IAT function. IMO, the HP/TQ thing doesn't work that well and is definitely not necessary. At best, it can function as a relative guideline to any tuning improvements.

However, the IAT function is definitely worthwhile if you want to have one card for all temps. I guess I am one of a very few who has dialed this in. I think it works great. Is it perfect? No. One of the reasons being the supercharged air charge is not a linear function of IAT. That being said, when your WB gives a you an AFR reading ....that non-linear function becomes somewhat irrelevant.

Here's the little rub if you do a VEC 2 upgrade...........A VEC 2 upgrade is not the same as a VEC 3 as far as working the program goes for getting it started up. Sean has instructions for what must be done for it to work properly. The VEC 2 program must be installed on your computer for the upgrade to work. I also have some more detailed instructions -- like a job journal sort of thing...which might be helpful.

The VEC 2 to VEC 3 upgrade is a physical upgrade. It must be sent in.

Steve

 

KenH

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Here's my 2 cents worth.

The good thing about a dyno tune is that you will be able to hear detonation much easier and is good for troubleshooting, especially if it is a load dyno, but a road tune will give better tuning results in my experience.

I'm not sure what you mean by 12.5 degrees of timing. You should not be too much over the stock advance with water/methanol. Certainly pulling some timing out is an easy change to try, but you need to pull out a couple of degrees to see much effect. Pulling some timing will also cause the A/F to richen up.

If you are running water/methanol, running too little or too much can cause hard to find tuning issues.

Just because you are running the Roe base tune doesn't necessarily mean your tune is close. My car would barely run at all on the base tune and I had to tune from scratch beginning with the injector offset which had to be set drastically different than the base tune used.

If you want to increase your octane and can't get race gas, get Torco Accelerator. The stuff really works unlike what you find down at the local auto store. a can will take a tank of gas from 92 octane to 96 or so. It will leave some orange magnesium deposits on the plugs, but it doesn't seem to hurt anything.

Another thing to look for is that the TPS sensor is still getting it's full range since the SC install. On my car it was reading a little low and the car was never going into Open Loop mode. That plays havoc when trying to tune at WOT as the O2 sensors keep trying to pull fuel out since they are still in circuit. That could easily lead to detonation. I had to move the throttle bracket back on my car to take care of that problem. The best way to check this is to have you local Viper tech hook up a scan tool and then go take him for a WOT pull or two while monitoring open/closed loop operation.

A WB installed into one or both sides is the best investment that you can make if you are going to do any tuning yourself. Even if someone else tunes your car for you, a WB lets you keep an eye on the tune, which can move around a bit. I have a Wideband Commander on just my driver side which is wired into the VEC so that I can log it along with the other VEC parameters and it has worked fine. I did balance the injectors on the drivers and passenger side banks using the stock O2 sensors and the EASE software that Roe used to sell as well as some plug readings to balance the cylinders on each side.

The VEC 3's main value is the AIT input that lets you compensate for temperature changes without retuning the car. My car was so bad that it could detonate in the cool morning air and then be running so rich that it would run crappy in the hot afternoon. After I got everything else sorted out (and I had a lot of issues not even listed here) this was the thing that made me regret getting the Roe. I was dead set on upgrading my VEC2 to a VEC3, but by coincidence, I installed an air intake from PBJ that mounts the AIT sensor right in the airflow last summer. My huge swings in A/F with temperature have almost gone completely away now that the sensor is reading the real air temp. With the stock air box, the AIT reading would quickly shoot up past 100 degrees with the car idling in the garage. With the new air box, the AIT stays right at true ambient.

As for the HP/TQ readings, I have that on my VEC2. I wouldn't place much stock in the #s, but I have been able to observe dips in the torque curve that I was able to smooth out by adding some timing advance in those spots, so I do think it has some value as a tuning tool.
 

Steve 00RT/10

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Ken,

Our 2001 car has the same exhaust set up as yours. 5 pound/no w/m. When I upgraded the 2002 VEC (2001 car) to be able to log, I immediately noticed much higher IAT temps in the logs than the 2000 car. I couldn't figure it out for quite a while. Then it hit me -- I have a Vipair on the 2000 car. The log temps in the same outside ambient temperature between the cars is as much as 25 degrees different---especially after getting hot or idling in the garage. I have set both cars LTFT to around zero by adjusting both base set (had to go up) and individual trim. EASE software from Sean.

I also now have first hand expereince with the 3rd tube thing as this 01 car came to us that way. Even though, I had tuned the WOT portion and LTFT, it was running extremely fat in closed loop. I had black soot on the garage floor at start up and would get a nice puff of black smoke on transtion to boost. I bought some Quick Fires this winter and put them in last week. The left bank was running -27% and the right around -15%. (the 3rd tube plugs looked great as that's all the computer was seeing). I reduced the base set 2% and redid the LTFT. Reducing the base set has more effect on WOT than the cylinder trim as the ensuing logs showed. I added a little fuel and it's good to go. Starting the car the next day produced no black soot, but rather some nice white smoke -- like it should be.
To me, this is absolute proof that the OEM O2 belongs in the collector area -- sensing all 5 cylinders with the computer trimming the average of the 5.

I have the TPS wired into my VECs as well. I run between 3.7 and 3.92 volts at WOT if I remember right. I also have my upper IAT set at 126 degrees....any hotter than that, I'll just run a little rich -- letting the fuel do a little cooling.....just like the factory sent it to us.

Steve
 
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SYNFULL

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Here's my 2 cents worth.

The good thing about a dyno tune is that you will be able to hear detonation much easier and is good for troubleshooting, especially if it is a load dyno, but a road tune will give better tuning results in my experience.

I'm not sure what you mean by 12.5 degrees of timing. You should not be too much over the stock advance with water/methanol. Certainly pulling some timing out is an easy change to try, but you need to pull out a couple of degrees to see much effect. Pulling some timing will also cause the A/F to richen up.
I talked to Tony Armour last night and he explained the timing to me. Where I was taking timing out was the wrong place. I am going to try the changes when I go to the dyno shop today.

If you are running water/methanol, running too little or too much can cause hard to find tuning issues.
Not even messing with this yet.

Just because you are running the Roe base tune doesn't necessarily mean your tune is close. My car would barely run at all on the base tune and I had to tune from scratch beginning with the injector offset which had to be set drastically different than the base tune used.
Thanks- I thought I was the exception to the rule.:)

If you want to increase your octane and can't get race gas, get Torco Accelerator. The stuff really works unlike what you find down at the local auto store. a can will take a tank of gas from 92 octane to 96 or so. It will leave some orange magnesium deposits on the plugs, but it doesn't seem to hurt anything.

Another thing to look for is that the TPS sensor is still getting it's full range since the SC install. On my car it was reading a little low and the car was never going into Open Loop mode. That plays havoc when trying to tune at WOT as the O2 sensors keep trying to pull fuel out since they are still in circuit. That could easily lead to detonation. I had to move the throttle bracket back on my car to take care of that problem. The best way to check this is to have you local Viper tech hook up a scan tool and then go take him for a WOT pull or two while monitoring open/closed loop operation.
This I will definetely check- Very possible since I had the throttle bracket in different locations.


A WB installed into one or both sides is the best investment that you can make if you are going to do any tuning yourself. Even if someone else tunes your car for you, a WB lets you keep an eye on the tune, which can move around a bit. I have a Wideband Commander on just my driver side which is wired into the VEC so that I can log it along with the other VEC parameters and it has worked fine. I did balance the injectors on the drivers and passenger side banks using the stock O2 sensors and the EASE software that Roe used to sell as well as some plug readings to balance the cylinders on each side.
My next step.

The VEC 3's main value is the AIT input that lets you compensate for temperature changes without retuning the car. My car was so bad that it could detonate in the cool morning air and then be running so rich that it would run crappy in the hot afternoon. After I got everything else sorted out (and I had a lot of issues not even listed here) this was the thing that made me regret getting the Roe. I was dead set on upgrading my VEC2 to a VEC3, but by coincidence, I installed an air intake from PBJ that mounts the AIT sensor right in the airflow last summer. My huge swings in A/F with temperature have almost gone completely away now that the sensor is reading the real air temp. With the stock air box, the AIT reading would quickly shoot up past 100 degrees with the car idling in the garage. With the new air box, the AIT stays right at true ambient.

As for the HP/TQ readings, I have that on my VEC2. I wouldn't place much stock in the #s, but I have been able to observe dips in the torque curve that I was able to smooth out by adding some timing advance in those spots, so I do think it has some value as a tuning tool.
Thank for all your help!
 

KenH

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Steve,
These cars all seem to behave differently. When I put my stock O2 sensors in the collectors, my car ran very lean. Around 18:1 at idle and I would get some lean misfire. The EASE software showed that they were reading a lean condition, yet if I put in more fuel with the VEC, I would throw a too rich code. Once I put the O2s up in the header tube, the car settled right down. I never could find an exhaust leak or similar that might account for that odd behavior and logically I could not figure out why it was behaving like it was. I agree 100% with the logic of sensing the average of all 5 cylinders down in the collector, but my car didn't like it. Come to think of it, my car didn't like a lot of things about the SC install.

Regarding the AIT sensor, I was really surprised how big an effect changing the mounting had on the stability of the tune in the VEC. I can image the Vipair having a similar affect when underway, but surprised that you would see that much difference just idling in the garage since the air box stayed the same. Did you notice any difference in how the tune held up over temperature between the two cars (assuming they both have Roe SCs)?
 

EllowViper

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I have my IAT in my intake tube right before my W/M injection nozzle. I doubt I get too much variation other than the actual ambient temp since outside air is always flowing over the sensor. Can't get heat soaked either sitting in traffic, etc for the same reason. I could never figure out why an IAT would be located in such a manner as to have engine/radiator heat artificially influence the "outside" air temp reading. The stock airbox gets pretty hot...ergo the IAT sensor too.
 

Steve 00RT/10

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Steve,
These cars all seem to behave differently. When I put my stock O2 sensors in the collectors, my car ran very lean. Around 18:1 at idle and I would get some lean misfire. The EASE software showed that they were reading a lean condition, yet if I put in more fuel with the VEC, I would throw a too rich code. Once I put the O2s up in the header tube, the car settled right down. I never could find an exhaust leak or similar that might account for that odd behavior and logically I could not figure out why it was behaving like it was. I agree 100% with the logic of sensing the average of all 5 cylinders down in the collector, but my car didn't like it. Come to think of it, my car didn't like a lot of things about the SC install.

Regarding the AIT sensor, I was really surprised how big an effect changing the mounting had on the stability of the tune in the VEC. I can image the Vipair having a similar affect when underway, but surprised that you would see that much difference just idling in the garage since the air box stayed the same. Did you notice any difference in how the tune held up over temperature between the two cars (assuming they both have Roe SCs)?

That is interesting about the O2 placement and does seem odd. I'm glad my cars like the OEM O2s in the right place, especially with the blower.

Yes, even in the garage, the AIT log temps are considerably lower. It definitely proves the theory about the massive amount of engine heat influencing the sensor in stock GEN II airbox form. If air is only allowed in from the NACA duct, like the Vipair, GEN I, and GEN III...... then it makes sense the IAT should be reduced. The main problem with our Roe cars, from a temp standpoint, is this is still not the air temp going into the engine.


Both cars have 5 pound Roes / no W/M. I have slightly different IAT parameters for each car. There is no doubt that the 2000 car is faster, but there are reasons for that.

2000 car: 5 pound Roe / Belanger headers /no cats/3" Belanger exhaust / light flywheel / 1.7 roller rockers / 3.45 gears and stock 18" wheels and tires.
2001 car: 5 Pound Roe / Belanger headers / hi flow cats / 3" Corsa track exhaust / light flywheel / 3.07 gears with 19" wheels and tires. That makes the effective rear end ratio a 2.92.

When we got the 01 car in late August 06, I felt like I was running blind without a wideband and ability to log. I sent the VEC 2 in for an upgrade to be able to log. I did very little tuning with the upgraded VEC2 to logging capabilities in late fall 2006. I then sent both units back in for the VEC 3 upgrade in January 2007. The 2001 car doesn't see a lot of use, 3200 miles since 9/06. It's more of a one of a kind car with some go fast parts. That being said, most of the tuning has been with IAT parameters in place. I have set 126 for the upper limit of fuel removal and have seen 135 temps in the few hot logs I've done. The tune does seem to drop off a little in hot weather, but that is also because I'm not removing fuel over 126F. For the use this car sees, I have it tuned plenty good enough for me.

There was a dyno sheet with it when we got it. It showed 554HP/586TQ ............and it was extremely fat. The first logs showed high 9s to mid 10s. I know I have added a little more power with what I've done. The dyno pull was done with stock wheels / tires.

Steve
 

KenH

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Good discussion!

EllowViper, I never thought about relocating the AIT to the intake tube, that makes a lot of sense. The stock airbox location is in dead air as far as I can tell.

Synfull, keep us posted on the results of your dyno tuning.

--- Ken
 

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I have my IAT in my intake tube right before my W/M injection nozzle. I doubt I get too much variation other than the actual ambient temp since outside air is always flowing over the sensor. Can't get heat soaked either sitting in traffic, etc for the same reason. I could never figure out why an IAT would be located in such a manner as to have engine/radiator heat artificially influence the "outside" air temp reading. The stock airbox gets pretty hot...ergo the IAT sensor too.

Putting the IAT sensor in the intake tube probably does give a slightly more accurate reading of air temp just before entering the intake/blower. However; unless you have a modified airbox which is pulling air from the NACA duct only............you're still gulping in the hotter air from the engine compartment and really haven't solved the air temp issue. As for idling in hot weather and heavy traffic, I have to think the tube area gets as hot or hotter than the stock side airbox location.....especially with the hood pad almost touching the tubes. This condition could maybe give a higher IAT reading than the stock location. I'm pretty well convinced that the modified airboxes, and even the Vipair, provide a better solution by eliminating some of the superheated engine compartment that the engine is trying to gulp in.

Steve
 
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SYNFULL

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I am on my way there now.
Question - I am going to install a wideband on drivers side for now. I have a pillar gauge pod that holds 2 gauges. I am thinking Boost, and Air Fuel. Anyone know or have these 2 gauges that match by the same mfgr. and look like they belong? I am thinking autometer has the largest selection - does anyone have this combination?
The Innovative XD-16 looks real nice but they are $230@
 
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Car Took A Dump

I am feeling pretty depressed right now.:(
Arrived at the shop to dyno tune my car. Finally got everything set up. Did the first run with some timing taken out and the car was still detonating. Then we made some more changes, the tuner called Tony Armour to clear up some points. Dyno'd the car again. This time it sounded great - no detonation- just brought it up to 5k and was getting 605 hp when antifreeze came from underneath. We cut everything off, cleaned up and found it came from the overflow bottle. Checked the fan and it wasn't coming on until about 205- decided I needed to get it to come on at a lower temp- don't know if the vec can control that. Anyhow did another run - car sounded great - Just when I thought we were in the home stretch we brought it up to 5k again and then antifreeze came shooting out of the top coolant bottle. :omg::omg::omg::crazy2::crazy2::crazy2:
They told me that the head gaskets have been torn up from the detonation and the compression is pushing the coolant out.
I didn't have much of a choice but to leave the car there as we were worried fluid entered the cylinder and could bend my rods if we started it up.
Estimate is 1600 (20 hours) plus parts. I don't have the time or energy to take the heads off again after I just did the whole heads s/c job.
The good news is they can tune it between the vec2, and their dyno. The tuner was even recommending that I get rid of the vec and use his program which has more control. He gives me a device (similar to or it is the SCT XCalibrator) that holds a few programs and is flashed to the pcm. I don't think you can log with it plus I don't want to spend the money on anything else right now.
Moral of the story is don't drive your car if it's detonating- unfortunately I have been trying to find out for 3 weeks if what I was hearing was detonation since it didn't sound like the usual description, and the plugs didn't show any sign of it.

Any chance this may be just a bad cap??
Thanks
 
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