In need of a tune?
12-30-2015, 08:32 AM
#1
Teching In
Thread Starter
Join Date: Oct 2015
Location: Bay Area
Posts: 30
Likes: 0
Received 0 Likes
on
0 Posts
In need of a tune? Will getting a tune make a big difference after replacing a few little things?
When it was bone stock w just a k&n cai, it ran strong and quick! It still runs, especially after replacing spark plugs from NGK iridiums to autolites double platinums. And of course the wires too.
But after over time, I put in long tube headers, the ram air intake, BBK under drive pulley, and an SLP loudmouth muffler. It just doesn't feel the same as it was when I had the stock exhaust in there. I would think that a tune would really help with the little things I've done to it.
I live in the Bay Area, so if any of you guys would know a shop that'll do a good tune let me know!
94 t/a m6
When it was bone stock w just a k&n cai, it ran strong and quick! It still runs, especially after replacing spark plugs from NGK iridiums to autolites double platinums. And of course the wires too.
But after over time, I put in long tube headers, the ram air intake, BBK under drive pulley, and an SLP loudmouth muffler. It just doesn't feel the same as it was when I had the stock exhaust in there. I would think that a tune would really help with the little things I've done to it.
I live in the Bay Area, so if any of you guys would know a shop that'll do a good tune let me know!
94 t/a m6
12-30-2015, 09:13 AM
#2
might help a bit. usually even after intake/exhaust on these things, they're really rich at heavy throttle, and can handle a bit more timing advance..also longtubes screw with closed loop and o2s a bit.
if you just want to pay a guy and get 'er done, try solomon, he's pretty affordable, and he's known to keep working with you until he nails it: http://www.lt1pcmtuning.com/
no need to take it to a shop with such small modifications
or if you want to learn to tune it yourself, all the tools in my signature are free (just need an ALDL cable) but be prepared, it's addictive and will consume your life...so you might just want to pony up the hundred bucks or whatever.
whatever you do, first make sure your car is in top running condition, no clogged injectors, good fuel pressure, clean MAF, etc. a lot of guys with these old engines tend to think a problem is in the tune, when it's actually something else causing the power loss
if you just want to pay a guy and get 'er done, try solomon, he's pretty affordable, and he's known to keep working with you until he nails it: http://www.lt1pcmtuning.com/
no need to take it to a shop with such small modifications
or if you want to learn to tune it yourself, all the tools in my signature are free (just need an ALDL cable) but be prepared, it's addictive and will consume your life...so you might just want to pony up the hundred bucks or whatever.
whatever you do, first make sure your car is in top running condition, no clogged injectors, good fuel pressure, clean MAF, etc. a lot of guys with these old engines tend to think a problem is in the tune, when it's actually something else causing the power loss
12-30-2015, 09:15 AM
#3
Teching In
Thread Starter
Join Date: Oct 2015
Location: Bay Area
Posts: 30
Likes: 0
Received 0 Likes
on
0 Posts
Yeah I thought about getting a high flow MAF as well. Plus when I removed my spark plugs, cyl 8 plug was really fouled so I've been told it is running rich
12-30-2015, 01:59 PM
#5
TECH Resident
Don't waste your money. There is no reason to change from the stock MAF with the power you are making now. Not only that, but the new MAF will need a new calibration in the PCM....so spend the money elsewhere.
Last edited by ACE1252; 01-02-2016 at 03:21 PM.
Trending Topics
01-01-2016, 10:18 AM
#8
You need to learn to research, the underdrive pulley was pretty much a mistake and the "high flow MAF" would have been a bigger mistake.
Tuning will help.
When was the last time you did a cap and rotor?
Gears would be the next thing on the list and would need a retune so consider them and a tune at the same time.
There are lots of bad parts out there designed to take your money and many that just aren't worthwhile as well. For instance the MAF, one of the tuners with a over 500rwhp car, which would be on the order of twice what you's is was saw a single digit HP gain from removing the MAF and putting a larger pipe there and tuning it for no MAF. A bigger one might be wildly unreliable like the Granatelli and best case would make the car harder to tune.
The underdrive pulley is best left to cars with belt driven waterpumps. Many of us remove the serpentine belt when drag racing and see .1 gain from doing so. Based on that the underdrive of what 34% should gain you a whole .034 at the track.
Cars with a belt driven waterpump have a much greater load on the belt so it offers more potential gains.
Tuning will help.
When was the last time you did a cap and rotor?
Gears would be the next thing on the list and would need a retune so consider them and a tune at the same time.
There are lots of bad parts out there designed to take your money and many that just aren't worthwhile as well. For instance the MAF, one of the tuners with a over 500rwhp car, which would be on the order of twice what you's is was saw a single digit HP gain from removing the MAF and putting a larger pipe there and tuning it for no MAF. A bigger one might be wildly unreliable like the Granatelli and best case would make the car harder to tune.
The underdrive pulley is best left to cars with belt driven waterpumps. Many of us remove the serpentine belt when drag racing and see .1 gain from doing so. Based on that the underdrive of what 34% should gain you a whole .034 at the track.
Cars with a belt driven waterpump have a much greater load on the belt so it offers more potential gains.
01-01-2016, 01:09 PM
#9
11 Second Club
I would only consider an under drive pulley if your turning high rpm and don't wanna ruin your accessories.. Any hp gain would just be a plus..
01-01-2016, 03:59 PM
#10
i had an underdrive pulley for a while just because the car came with one. i didn't notice any ill effects, but it definitely didn't benefit anything. i noticed the voltmeter would drop a little bit in traffic at night with the heat and high beams on, but no big deal. if i had a bunch o subwoofers, though, that might have tipped it over the edge. have your tuner raise your idle RPM by 100rpm or something just in case.
the stock lt1 maf is a high flow maf.
I thought about getting a high flow MAF
01-01-2016, 04:40 PM
#11
You need to learn to research, the underdrive pulley was pretty much a mistake and the "high flow MAF" would have been a bigger mistake.
Tuning will help.
When was the last time you did a cap and rotor?
Gears would be the next thing on the list and would need a retune so consider them and a tune at the same time.
There are lots of bad parts out there designed to take your money and many that just aren't worthwhile as well. For instance the MAF, one of the tuners with a over 500rwhp car, which would be on the order of twice what you's is was saw a single digit HP gain from removing the MAF and putting a larger pipe there and tuning it for no MAF. A bigger one might be wildly unreliable like the Granatelli and best case would make the car harder to tune.
The underdrive pulley is best left to cars with belt driven waterpumps. Many of us remove the serpentine belt when drag racing and see .1 gain from doing so. Based on that the underdrive of what 34% should gain you a whole .034 at the track.
Cars with a belt driven waterpump have a much greater load on the belt so it offers more potential gains.
Tuning will help.
When was the last time you did a cap and rotor?
Gears would be the next thing on the list and would need a retune so consider them and a tune at the same time.
There are lots of bad parts out there designed to take your money and many that just aren't worthwhile as well. For instance the MAF, one of the tuners with a over 500rwhp car, which would be on the order of twice what you's is was saw a single digit HP gain from removing the MAF and putting a larger pipe there and tuning it for no MAF. A bigger one might be wildly unreliable like the Granatelli and best case would make the car harder to tune.
The underdrive pulley is best left to cars with belt driven waterpumps. Many of us remove the serpentine belt when drag racing and see .1 gain from doing so. Based on that the underdrive of what 34% should gain you a whole .034 at the track.
Cars with a belt driven waterpump have a much greater load on the belt so it offers more potential gains.
I would do the following, keeping to the above,
1. invest $$ into a tune-up (cap wires plugs filters)
2. for a stock engine, use mostly stock parts
3. put $$ Into the drivetrain and suspension before going for power output. I would address the transmssion internals (automatic) and converter for instance, before attempting to gain even a single horsepower from the engine.
4. when it comes time for a performance kick, use a turbocharger or a very small shot of nitrous. Both of these may carry over onto the next engine and have avenues of enhancement/options.
5. avoid small parts/nickel and dimes worth of horsepower. leave the larger mafs and one-shot mods out of your vehicle. I even prefer the OEM intake plumbing fwiw, and the OEM paper filters, even for high output situations which are daily driven.
01-02-2016, 03:36 AM
#13
On The Tree
starting at 1.20 into this video you will see what makes a Granatelli MAF head and shoulders above the rest.
If we he a buck for all the confused nay sayers that made a negative comment about a stock ported MAF and dragged Granatelli down ....well you know the story
1. The GRANATELLI MAF is 50 state legal - that proves its 100% calibrated. If were just a stock or aftermarket oversized meter it would make teh car run lean and never pass (reach) the OE standard
2. Going Speed Density - (getting rid of the MAF) is backward thinking and only works for WOT. Why give up all that is good about the MAF
3. GMS also offers transfer funtion sheets when selling their over sized race meters for both FORD and / or GM
01-02-2016, 07:38 AM
#14
Seen one lone report in more than a decade on the forums of a Granatelli MAF adding a repeatable 3hp to a cammed car and many more of them causing tuning hassles and failing early, including the one I tried to test for a friend when he made the mistake of buying one so I have actual experience.
01-02-2016, 09:56 AM
#15
On The Tree
Well. I'm not going to thread jack. Just say'n the facts.
Remember
"we mock what we don't understand"
You're saying GM sells junk MAFs because Granatelli worked hand in hand with them and Delphi to Co design and develop these MAFs starting in in 1998 for model years 2000 forward.
If a car gains 3hp at the rear wheels that would be an increase of 5 cfm. The MAF does not change total timing and a camshaft change usually benefits from a timing change - or in other words a tune change. The MAF alone cant do that. So again "from personal experience" an experienced tuner would know that.
In today's world of tech - we now know that a MAF (or any intake) system can be properly sized and calibrated. So I would agree for the most part a proper tune is required to get the most out of any combination.
It just a poor mechanic that blames his tools.
Remember
"we mock what we don't understand"
You're saying GM sells junk MAFs because Granatelli worked hand in hand with them and Delphi to Co design and develop these MAFs starting in in 1998 for model years 2000 forward.
If a car gains 3hp at the rear wheels that would be an increase of 5 cfm. The MAF does not change total timing and a camshaft change usually benefits from a timing change - or in other words a tune change. The MAF alone cant do that. So again "from personal experience" an experienced tuner would know that.
In today's world of tech - we now know that a MAF (or any intake) system can be properly sized and calibrated. So I would agree for the most part a proper tune is required to get the most out of any combination.
It just a poor mechanic that blames his tools.
01-02-2016, 12:01 PM
#16
If I can make a 4200lbs sled drive 150miles and clip off mid 11s NA I am probably not a poor mechanic, but you sir are a great salesman.
Thanks for the tip on the MAFs so if we want a "Granatelli" all we have to do is hit a junkyard and pull from a 2000+ application.
Thanks for the tip on the MAFs so if we want a "Granatelli" all we have to do is hit a junkyard and pull from a 2000+ application.
01-02-2016, 07:29 PM
#17
A maf is a great thing when used in the right conditions.
The larger you go with the maf the less resolution you have to tune with. Always use the smallest possible maf for best accuracy of fueling. They also require a system without leaks, and a smooth flow characteristic for best results (no nearby bends, no fluctuating/pulsating airflow such as when a compressor wheel is surging, buffeting the maf hotwire)
For performance situations, a maf represents a slight restriction, and so for the sake of all wide open throttle performance applications where power > economy, you will want to ditch the maf. For street cars, however, keeping the right size maf is an easy way to get maximum economy, if plumbed properly. From experience, I know that I can match or exceed the economy of a maf with a MAP sensor, but it will take easily 10x the time tuning.
The larger you go with the maf the less resolution you have to tune with. Always use the smallest possible maf for best accuracy of fueling. They also require a system without leaks, and a smooth flow characteristic for best results (no nearby bends, no fluctuating/pulsating airflow such as when a compressor wheel is surging, buffeting the maf hotwire)
For performance situations, a maf represents a slight restriction, and so for the sake of all wide open throttle performance applications where power > economy, you will want to ditch the maf. For street cars, however, keeping the right size maf is an easy way to get maximum economy, if plumbed properly. From experience, I know that I can match or exceed the economy of a maf with a MAP sensor, but it will take easily 10x the time tuning.
01-05-2016, 06:22 AM
#18
Grannatelli, first ill say I do appreciate you coming in here and supporting your product, not many sponsors visit the bastard LTx section.
Here is my statement on the aftermarket MAF topic. Your MAF is $325. If it gained 3hp, that's $100 a HP, not anywhere near a bargain or anything you would feel or see at the track. On a stockish car, or anything making less than 450rwhp, it could be nothing because the MAF hasn't become a restriction yet. If you are starting at 280rwhp, and have the option of a $1600 heads/cam package that will gain 100hp, being $16 a HP, where would you spend your money? Return on investment drops as you get higher and higher in HP, not every HP costs $15-50, there is a point where all added HP is going to cost $100/hp, but he's not there yet. For anything less than an all out, I've run out of **** to do that adds power build, an aftermarket MAF isn't worth it.
Here is my statement on the aftermarket MAF topic. Your MAF is $325. If it gained 3hp, that's $100 a HP, not anywhere near a bargain or anything you would feel or see at the track. On a stockish car, or anything making less than 450rwhp, it could be nothing because the MAF hasn't become a restriction yet. If you are starting at 280rwhp, and have the option of a $1600 heads/cam package that will gain 100hp, being $16 a HP, where would you spend your money? Return on investment drops as you get higher and higher in HP, not every HP costs $15-50, there is a point where all added HP is going to cost $100/hp, but he's not there yet. For anything less than an all out, I've run out of **** to do that adds power build, an aftermarket MAF isn't worth it.
01-05-2016, 11:03 AM
#20
A maf is not supposed to "give you power" its just a tube with a wire inside that helps the computer know how many moles/time your engine is ingesting.
How do you know if you "need a bigger maf"?
Well here is a short rundown of this exact situation / question.
The air filter presents a slight restriction before the intake tube, whether your engine is N/A or turbo or supercharged, you should have an air filter on it. The pressure after the air filter can be measured with a gauge- just like the manifold pressure or exhaust pressure, there is some number which we can compare to atmospheric pressure that tells us how much "restriction" the air filter is causing. The difference is small so you need a very sensitive gauge, one that measures in Inches of Water, like this one
http://www.ebay.com/itm/381017656706?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
That gauge reads 0 to 60 inches of water, or something like 0 to 2" of Mercury. In other words, compared to a typical vacuum gauge which reads 0 to 28" of mercury, it has nearly 14 times the resolution for the same dial sweep area as a typical manifold pressure gauge (they are pressure gauges, not "vacuum gauges" but I will use the two words interchangeably in this case)
What you want to do is install this very sensitive gauge after your air filter and watch what it reads when your engine makes peak horsepower. If you can buy an electronic gauge and log the data then this would be ideal; (we cant always watch our gauges at WOT). The amount of vacuum present behind a clean, properly sized air filter, will be minimal; you might see 5" of water or 15" of water for example.
Here is where I point out that the factory generally uses this location for PCV action, especially on a turbo engine where this is the only place to get a reliable source of any kind of vacuum signal during boost. That is, the vacuum signal here is essential to running the pcv system during boost at WOT. In other words, the slight restriction presented by your air filter is necessary to drive PCV during WOT. By eliminating the slight restriction you are ruining your PCV vacuum signal and allowing crankcase pressure to escalate during WOT, an undesirable situation for many reasons.
Now, I want you to think about the above, and then consider the maf sensor exactly as you would an air filter, that is, it presents a slight restriction that is helpful to PCV action during WOT. The MAF also works best when it is smallest; i.e. just like our "high resolution vacuum gauge" a smaller maf allows for higher resolution tuning of fuel, better economy and better use of fuel is the result when using smaller maf sensors. The point at which the maf OR air filter is TOO SMALL is only when the pressure in this location (post maf / post filter on any engine) begins to become significantly low for the application(A race car running a belt driven vacuum pump has no such need for intake tube driven vacuum signal, and thus can run an enormous or no air filter without consequences to PCV), perhaps 18"+ of water (around 1" of HG) you may notice 1/25~ of your peak power disappear. So herein lies the trade-off, you are giving up a tiny bit of power anyways by running a slight restriction after your air filter in exchange for cleaner air and a functional PCV system, and anything else in the plumbing which presents a similar slight restriction such as bends in the plumbing (at high speeds air turning a bend may slow down causing a change in pressure) or too small of a throttle body (you can measure the pressure in front of the throttle body with a sensitive gauge and determine the pressure difference before/after the same way I just showed for the air filter and maf) or maf sensor will also have an effect on the final number at the engine.
In fact, even if the vacuum after my maf/filter was significant, I still wouldn't opt for the larger maf sensor, since I only see that slight vacuum at absolute wide open throttle peak power, and if the car is a daily driver I will care more about the fuel resolution and economy benefits of running a small/OEM maf sensor than the tiny eety bit of peak power potential I would gain by enlarging any of these listed items. I will also prefer that my air filter provides that slight restriction so I can have some PCV action during WOT as well.
TL;DR
Think of your maf similar to the air filter or throttle body or plumbing type of restriction. As the volume of air (not mass) flowing through them increases beyond a certain volume/time the restriction might increase to the point where you need to enlarge one or all of them, with daily drivers needing to be much more cautious than race cars when upgrading or enlarging these devices.
How do you know if you "need a bigger maf"?
Well here is a short rundown of this exact situation / question.
The air filter presents a slight restriction before the intake tube, whether your engine is N/A or turbo or supercharged, you should have an air filter on it. The pressure after the air filter can be measured with a gauge- just like the manifold pressure or exhaust pressure, there is some number which we can compare to atmospheric pressure that tells us how much "restriction" the air filter is causing. The difference is small so you need a very sensitive gauge, one that measures in Inches of Water, like this one
http://www.ebay.com/itm/381017656706?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
That gauge reads 0 to 60 inches of water, or something like 0 to 2" of Mercury. In other words, compared to a typical vacuum gauge which reads 0 to 28" of mercury, it has nearly 14 times the resolution for the same dial sweep area as a typical manifold pressure gauge (they are pressure gauges, not "vacuum gauges" but I will use the two words interchangeably in this case)
What you want to do is install this very sensitive gauge after your air filter and watch what it reads when your engine makes peak horsepower. If you can buy an electronic gauge and log the data then this would be ideal; (we cant always watch our gauges at WOT). The amount of vacuum present behind a clean, properly sized air filter, will be minimal; you might see 5" of water or 15" of water for example.
Here is where I point out that the factory generally uses this location for PCV action, especially on a turbo engine where this is the only place to get a reliable source of any kind of vacuum signal during boost. That is, the vacuum signal here is essential to running the pcv system during boost at WOT. In other words, the slight restriction presented by your air filter is necessary to drive PCV during WOT. By eliminating the slight restriction you are ruining your PCV vacuum signal and allowing crankcase pressure to escalate during WOT, an undesirable situation for many reasons.
Now, I want you to think about the above, and then consider the maf sensor exactly as you would an air filter, that is, it presents a slight restriction that is helpful to PCV action during WOT. The MAF also works best when it is smallest; i.e. just like our "high resolution vacuum gauge" a smaller maf allows for higher resolution tuning of fuel, better economy and better use of fuel is the result when using smaller maf sensors. The point at which the maf OR air filter is TOO SMALL is only when the pressure in this location (post maf / post filter on any engine) begins to become significantly low for the application(A race car running a belt driven vacuum pump has no such need for intake tube driven vacuum signal, and thus can run an enormous or no air filter without consequences to PCV), perhaps 18"+ of water (around 1" of HG) you may notice 1/25~ of your peak power disappear. So herein lies the trade-off, you are giving up a tiny bit of power anyways by running a slight restriction after your air filter in exchange for cleaner air and a functional PCV system, and anything else in the plumbing which presents a similar slight restriction such as bends in the plumbing (at high speeds air turning a bend may slow down causing a change in pressure) or too small of a throttle body (you can measure the pressure in front of the throttle body with a sensitive gauge and determine the pressure difference before/after the same way I just showed for the air filter and maf) or maf sensor will also have an effect on the final number at the engine.
In fact, even if the vacuum after my maf/filter was significant, I still wouldn't opt for the larger maf sensor, since I only see that slight vacuum at absolute wide open throttle peak power, and if the car is a daily driver I will care more about the fuel resolution and economy benefits of running a small/OEM maf sensor than the tiny eety bit of peak power potential I would gain by enlarging any of these listed items. I will also prefer that my air filter provides that slight restriction so I can have some PCV action during WOT as well.
TL;DR
Think of your maf similar to the air filter or throttle body or plumbing type of restriction. As the volume of air (not mass) flowing through them increases beyond a certain volume/time the restriction might increase to the point where you need to enlarge one or all of them, with daily drivers needing to be much more cautious than race cars when upgrading or enlarging these devices.
Last edited by kingtal0n; 01-05-2016 at 11:11 AM.