Originally posted by Altim8GA Can you define highly moddified? Intake, pulley, and headers considered highly modded, or cams,ported, polished more along the lines of what you meant? I guess I'm talking about simple bolt on's (not turbo) equalling slightly modded.
I guess it means once you start getting insdie of the motor, like cams, plus all of the nomal bolt ons.
Originally posted by JKWright The QR is a big, highly undersquare four cylinder with an 89 mm bore and a 100 mm (!) stroke. Such a design inherently lends itself to wicked second-order vibrations, which is why Nissan decided to equip it with two balance shafts, a first in its U.S. lineup. Removing them initially may not hurt anything other than the fillings in your teeth, but as the miles pile up the added vibration will be tough on journals, bearings and the like. Not good, methinks.
Originally posted by morepower2 The QR is an internaly balanced engine and removing the balance shafts does not affect this.]
Strictly speaking, all production engines are internally balanced. But that doesn't mean that an inherently raucous design such as a long-stroke inline four can't benefit substantially from balance shafts. That's why Nissan sucked it up and increased the cost and complexity of the QR25 by installing them.
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In fact if you have a highly moddifed QR, it is important to remove the balance shafts as seizing the shafts is one of the engines frist failure points.
I don't doubt this, as balance shafts are basically large counterrotating weights. In a track-only or off-road application, removing them wouldn't present a problem at all, as NVH are the last of the bottom rung of considerations in racing applications. But pulling them out of a family sedan that's still under warranty and driven to and from the grocery store twice a week seems overkill to me, particularly if you're talking about a very minor horsepower gain. The trade-off just is not worth it. To warp one of my favorite lines, "My warranty for a pair of balance shafts!"
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On a QR removing the shafts results in a barily perceptable increse in vibration, the motor is still smoother than a KA24 and nearly as smooth as an SR20.
Having owned two SR20s and a KA24, even sticking those two engines in the same sentence seems to me a bad idea.
The term "barely perceptible" is of course relative. What's barely perceptible to a gung-ho-nitrous-equipped street rodder is overwhelming to John Four Door. Clearly, if the gain in adding a substantial amount of cost and complexity in the form of balance shafts in the QR25 were as small as you describe, the Nissan beancounters would never have approved their installation. Considering that the company couldn't be persuaded to part with an extra hundred-spot per Altima to upgrade the interior to, say, Malibu level, it makes no sense to assume that the company would drop several hundred on balance shafts that provide only "barely perceptible" decreases in NVH.
My advice: If your Altima or Sentra is a mild daily driver that you plan to keep for a few years and also in fact hope to sell for actual cash monies one day when you're done with it (rather than the alternative of wadding it up and tossing it into the ditch), leave the balance shafts in there.
Originally posted by JKWright Strictly speaking, all production engines are internally balanced. But that doesn't mean that an inherently raucous design such as a long-stroke inline four can't benefit substantially from balance shafts. That's why Nissan sucked it up and increased the cost and complexity of the QR25 by installing them.
The term "barely perceptible" is of course relative. What's barely perceptible to a gung-ho-nitrous-equipped street rodder is overwhelming to John Four Door. Clearly, if the gain in adding a substantial amount of cost and complexity in the form of balance shafts in the QR25 were as small as you describe, the Nissan beancounters would never have approved their installation. Considering that the company couldn't be persuaded to part with an extra hundred-spot per Altima to upgrade the interior to, say, Malibu level, it makes no sense to assume that the company would drop several hundred on balance shafts that provide only "barely perceptible" decreases in NVH.
My advice: If your Altima or Sentra is a mild daily driver that you plan to keep for a few years and also in fact hope to sell for actual cash monies one day when you're done with it (rather than the alternative of wadding it up and tossing it into the ditch), leave the balance shafts in there. [/b]
In the first Jarrod, you are wrong, there are many production engines that are externaly balanced, like most domestic engines!
As far as the validity of removing the balance shafts, no its not going to affect the engines durabilty and may even improve it under some conditions. The first few QR25's that were modifed for racing use failed because of extensive damage caused by balance shaft assembly failure. The shafts seize at high rpm, much past 6500 rpm in fact.
The reason for the balance shafts exsistance is not for durabilty but because the NVH target for the QR25 was to meet or exceed the NVH chariteristics of the VQ30DE engine. However I bet that many people wouldnot be able to tell that the balance shafts were removed if they were not promted, thats how subtile the differences are. In fact I had a hard time telling myself!
Plus for most people, finding 8-10 hp in a naturaly asperated engine is quite a large amount, especialy if its free hp without a fuel consumption penalty. This mod is also easily reversable, you can reinstall the balance shafts when you sell the car.
What you are stating as fact is only conjecture on your part and your opinion. You have never done any of these mods nor do you modify any of your cars. I have had these sorts of arguments with you on other forums before. In fact your famous Bosch spark plug argument was proven wrong once more data was avalible but after you dropped off that mailing list.
You are correct in your advice that if you are not a person into modding the car whose primary concern is to have a warranty and a lack of NVH, then don't remove the balance shafts, in fact don't consider any modifcations, keep your car totaly stock.
Here are the facts without any opinion from you or I.
1. Will void engine warranty
2. Will give 6-10 wheel hp depending on how done
3. Will improve durability under racing conditions
4. Will increase NVH by a very small amount.
5. With the JWT kit, is easy to reverse and put back to stock.
6. Will not hurt the engine under normal street use.
7. Will increse the amount of oil avalible to the main and rod bearings
8. The JWT kit will improve oil control, reduce windage and reduce oil starvation under cornering.
Whether or not this has any value to the consumer is up toi the consumer, anything else is just opinion.
Originally posted by morepower2 In the first Jarrod, you are wrong, there are many production engines that are externaly balanced, like most domestic engines!
As far as the validity of removing the balance shafts, no its not going to affect the engines durabilty and may even improve it under some conditions. The first few QR25's that were modifed for racing use failed because of extensive damage caused by balance shaft assembly failure. The shafts seize at high rpm, much past 6500 rpm in fact.
The reason for the balance shafts exsistance is not for durabilty but because the NVH target for the QR25 was to meet or exceed the NVH chariteristics of the VQ30DE engine. However I bet that many people wouldnot be able to tell that the balance shafts were removed if they were not promted, thats how subtile the differences are. In fact I had a hard time telling myself!
Plus for most people, finding 8-10 hp in a naturaly asperated engine is quite a large amount, especialy if its free hp without a fuel consumption penalty. This mod is also easily reversable, you can reinstall the balance shafts when you sell the car.
What you are stating as fact is only conjecture on your part and your opinion. You have never done any of these mods nor do you modify any of your cars. I have had these sorts of arguments with you on other forums before. In fact your famous Bosch spark plug argument was proven wrong once more data was avalible but after you dropped off that mailing list.
You are correct in your advice that if you are not a person into modding the car whose primary concern is to have a warranty and a lack of NVH, then don't remove the balance shafts, in fact don't consider any modifcations, keep your car totaly stock.
Here are the facts without any opinion from you or I.
1. Will void engine warranty
2. Will give 6-10 wheel hp depending on how done
3. Will improve durability under racing conditions
4. Will increase NVH by a very small amount.
5. With the JWT kit, is easy to reverse and put back to stock.
6. Will not hurt the engine under normal street use.
7. Will increse the amount of oil avalible to the main and rod bearings
8. The JWT kit will improve oil control, reduce windage and reduce oil starvation under cornering.
Whether or not this has any value to the consumer is up toi the consumer, anything else is just opinion.
Mike
As an ASE certified tech, Ill second that.
__________________
Patrick Scott
Yeah, thats a roll cage in there.
I shall call him...Mini-Me
Originally posted by morepower2 In the first Jarrod, you are wrong, there are many production engines that are externaly balanced, like most domestic engines!
You are absolutely correct and point well taken. My choice of words was poor; it's not like I've never heard of a harmonic balancer.
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As far as the validity of removing the balance shafts, no its not going to affect the engines durabilty and may even improve it under some conditions.
Here's the sticking point, Mike. The QR25 has been out for about a year, so any objective durability data available regarding balance shaft removal is nil. Show me a QR25 that's run for seven years and 200,000 miles without its balance shafts and we'll talk. Otherwise, you're throwing out the same type of educated conjecture I am on this subject.
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The reason for the balance shafts exsistance is not for durabilty but because the NVH target for the QR25 was to meet or exceed the NVH chariteristics of the VQ30DE engine.
Who said anything about durability in this sense? You're of course absolutely right, but if Nissan's target was VQ30DE smoothness with a balance shaft-equipped long-stroke inline four, well, you know as well as I do that such a target is a pipe dream. The two engines are not even close in NVH.
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However I bet that many people wouldnot be able to tell that the balance shafts were removed if they were not promted...
These people of whom you speak must be deaf and have no tactile sense whatsoever, then. While I can accept your statement that a QR without balance shafts is not exactly a Massey Ferguson, you and I both know that their installation helps NVH immensely. Nissan simply would not have gone to the trouble and expense of installing them if the perceived benefits in NVH were not substantial.
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In fact your famous Bosch spark plug argument was proven wrong once more data was avalible but after you dropped off that mailing list.
That still sticks in your craw after nearly six years? Holy cow, you've got a long memory. I salute you.
I am in fact still a subscribing member of the mailing list. Get my digests every day. As for the Bosch plug thing, well, you'll have to enlighten me as I still use them, though both the G20 and the Altima aren't due for another 90,000 miles. I do remember you being something of the Offical Purveyor of $20 NGK Spark Plugs. I think at one point you ran around sporting NGK stickers over every square inch of your body.
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You are correct in your advice that if you are not a person into modding the car whose primary concern is to have a warranty and a lack of NVH, then don't remove the balance shafts, in fact don't consider any modifcations, keep your car totaly stock.
I've always found it interesting that you have a difficult time subjectifying the term "modding." That is, in your world, either you go balls-out and build a barely driveable 400-horsepower monster or you don't mod at all. There is in fact, Mike, a large majority of enthusiasts who enjoy lightly modifying their cars for a few extra horses while attempting to retain their cars' full investment value and factory warranty. Removing the balance shafts in most cases is a bad idea for the six to 10 wheel horsepower you may gain for the simple fact that a) it's relatively complicated for the average enthusiast; b) it absolutely, unequivocally voids your warranty; c) it increases NVH substantially; and d) it may affect long-term reliability.
The first three points are inarguable; the last is what I'll call enlightened conjecture, just as any statement you make to the contrary regarding it. There's zero evidence to analyze on the issue. Only common sense.
Regardless, Mike, it's good to debate with you again. I always enjoyed it. Why the heck are you on an Altima forum? Finally found the merits of six pots instead of four?
Here's the sticking point, Mike. The QR25 has been out for about a year, so any objective durability data available regarding balance shaft removal is nil. Show me a QR25 that's run for seven years and 200,000 miles without its balance shafts and we'll talk. Otherwise, you're throwing out the same type of educated conjecture I am on this subject.
Dave Coleman's Car has been fine as well as the other racing QRs. Im sure you know that racing miles about the same as big multiples of street miles. So we could say that these cars have a good amount of milage in a sense. Since we all know that racing miles are harder than street miles, one could almost say that if a race engine has had no trouble a street engine wont have any trouble. Do you think a company with the rep of JWT would put out a part(s) that would end up damaging engines in the long run?
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Who said anything about durability in this sense? You're of course absolutely right, but if Nissan's target was VQ30DE smoothness with a balance shaft-equipped long-stroke inline four, well, you know as well as I do that such a target is a pipe dream. The two engines are not even close in NVH.
How many different QR cars have you been in? The ones I have been do feel close and mabe even meet that target. Maybe Im "deaf and have no tactile sense whatsoever", but I doubt that.
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These people of whom you speak must be deaf and have no tactile sense whatsoever, then. While I can accept your statement that a QR without balance shafts is not exactly a Massey Ferguson, you and I both know that their installation helps NVH immensely. Nissan simply would not have gone to the trouble and expense of installing them if the perceived benefits in NVH were not substantial.
Have you been in a QR powered car without the balance shafts? If not how can you say that they help immensely i this specific application?
The rest I wont even touch. I am only debating here, please dont take it as flamming or hating.
__________________
Patrick Scott
Yeah, thats a roll cage in there.
I shall call him...Mini-Me
You are absolutely correct and point well taken. My choice of words was poor; it's not like I've never heard of a harmonic balancer.
Here's the sticking point, Mike. The QR25 has been out for about a year, so any objective durability data available regarding balance shaft removal is nil. Show me a QR25 that's run for seven years and 200,000 miles without its balance shafts and we'll talk. Otherwise, you're throwing out the same type of educated conjecture I am on this subject.
[/b]
Who said anything about durability in this sense? You're of course absolutely right, but if Nissan's target was VQ30DE smoothness with a balance shaft-equipped long-stroke inline four, well, you know as well as I do that such a target is a pipe dream. The two engines are not even close in NVH.
These people of whom you speak must be deaf and have no tactile sense whatsoever, then. While I can accept your statement that a QR without balance shafts is not exactly a Massey Ferguson, you and I both know that their installation helps NVH immensely. Nissan simply would not have gone to the trouble and expense of installing them if the perceived benefits in NVH were not substantial.
[/b]
That still sticks in your craw after nearly six years? Holy cow, you've got a long memory. I salute you.
I am in fact still a subscribing member of the mailing list. Get my digests every day. As for the Bosch plug thing, well, you'll have to enlighten me as I still use them, though both the G20 and the Altima aren't due for another 90,000 miles. I do remember you being something of the Offical Purveyor of $20 NGK Spark Plugs. I think at one point you ran around sporting NGK stickers over every square inch of your body.
[/b]
I've always found it interesting that you have a difficult time subjectifying the term "modding." That is, in your world, either you go balls-out and build a barely driveable 400-horsepower monster or you don't mod at all. There is in fact, Mike, a large majority of enthusiasts who enjoy lightly modifying their cars for a few extra horses while attempting to retain their cars' full investment value and factory warranty. Removing the balance shafts in most cases is a bad idea for the six to 10 wheel horsepower you may gain for the simple fact that a) it's relatively complicated for the average enthusiast; b) it absolutely, unequivocally voids your warranty; c) it increases NVH substantially; and d) it may affect long-term reliability.
The first three points are inarguable; the last is what I'll call enlightened conjecture, just as any statement you make to the contrary regarding it. There's zero evidence to analyze on the issue. Only common sense.
Regardless, Mike, it's good to debate with you again. I always enjoyed it. Why the heck are you on an Altima forum? Finally found the merits of six pots instead of four?
Cheers, [/b]
Dammit, the vB codes don't seem to work for me so sorry if this is not well connected.
The problem I have with your arguments is that your opinions are simply opinions basied on conjecture with no experiance, like I always did on the SE-R list, I can call you an armchair modder, automotive engineerer, etc. Do you own a modifed car?no, do you race? no, are you an automotive engineer? no, are you actively involved with developing any sort of part for the industry? no. Thats a lot of no's to have such an objective opinion with such subjective data. I think I can answer all of those questions with yes.
What I post on is based on what has been done, what I have done or from feedback from professionals that I work with. I have driven a few cars with the balance shafts removed and was shocked and dismayed on what little difference in NVH they made. Go to b15sentra.net and ask those have actualy done this mod, I am sure they will share the same opinion as I. You on the other hand have nevber been within 300 feet of a QR with no balance shafts I bet.
I have been involved with modding several QR's for racing and seen the problems in developing these motors for racing use. The balance shafts actualy create durabilty issues in severe racing use. A season of endurance road racing or Pro-Rally is much more taxing that 200 k of normal highway driving, to figue that out simply firgure out the revolutions the motor turns in comparable use compare to in racing. Thats not even calculating the load differences on the componets. Your opinions are conjecture, mine are from actualy doing and experiancing, especialy on the QR25.
I remember the spark plug argument well! You are my favorite guy to argue with. After Chris Pinthong Dynoed his car with the Bosch plugs, he drove with the plugs for a while then redynoed to find a power loss. He then reinstalled some old 60k mile OEM plugs and guess what? The power came back and the weird driveabilty issues he was experiancing but did not attibute to the Bosch plugs instantly disappered. If you remember, Chris was your big supporter in your efforts to prove my advice for using OEM plugs wrong. Well he admitted to me that he was very wrong but never bothered to post anything about it.
As far as my 400 hp creations being undrivable, they are well engieered street machines, daily drivable calm and easy to manage and mosters when given the spurs. Ask b15sentra.net webmaster David Evans, or SCC engineering editor Dave Coleman who have both driven the Disco Potato B15 that I helped build and let them tell you how tractable and friendly that motor is and what a dream it is to drive, even in bumper to bumper traffic. Ask Ryan Besterwich, Ron Avacedo, Jay Hassigner, Aaron LeBeau, Mike Mager and many others if my creations are tempermental moody machines, they will tell you no.
I have probably had my hand in 70-80% of the Non -Stillen performance parts currently out for the Sentra family from mild to wild, I don't see how you can say that I only have experiance in extremes. If you ever do ventrue out and mod your car, chances are that I was consulted in some aspect of the part you are installing on your car. From an AEM intake to the JWT balance shaft removal kit, the F-Max turbo system, to a Hotshot header, GC coiloversand even a JWT camshaft, I had a role in bringing it to market. I am not a promoter of extremes, I understand all aspects of the industry from mild to wild.
Anyway my opinion are much less conjecture than yours are. Yours are pure opinion and conjecture. Mine arte based on actual happenings and experiance, lets leave it to the readers of this thread, who are you gonna belive?
How come you don't post on the se-r mailing list anymore? I miss you
Ok, so some belive that this causes problems after a few years, and some belive that this causes no problems what so ever. I want to see some posts on other forums before I continue with this. Please continue to weigh in. I'm lernin sumtin.
__________________
Even Ice Cube calls me an OG. Ez-E would, but well, you know....he had relations with Mike Young.
Originally posted by morepower2 Dammit, the vB codes don't seem to work for me so sorry if this is not well connected.
The problem I have with your arguments is that your opinions are simply opinions basied on conjecture with no experiance, like I always did on the SE-R list, I can call you an armchair modder, automotive engineerer, etc. Do you own a modifed car?no, do you race? no, are you an automotive engineer? no, are you actively involved with developing any sort of part for the industry? no. Thats a lot of no's to have such an objective opinion with such subjective data. I think I can answer all of those questions with yes.
What I post on is based on what has been done, what I have done or from feedback from professionals that I work with. I have driven a few cars with the balance shafts removed and was shocked and dismayed on what little difference in NVH they made. Go to b15sentra.net and ask those have actualy done this mod, I am sure they will share the same opinion as I. You on the other hand have nevber been within 300 feet of a QR with no balance shafts I bet.
I have been involved with modding several QR's for racing and seen the problems in developing these motors for racing use. The balance shafts actualy create durabilty issues in severe racing use. A season of endurance road racing or Pro-Rally is much more taxing that 200 k of normal highway driving, to figue that out simply firgure out the revolutions the motor turns in comparable use compare to in racing. Thats not even calculating the load differences on the componets. Your opinions are conjecture, mine are from actualy doing and experiancing, especialy on the QR25.
I remember the spark plug argument well! You are my favorite guy to argue with. After Chris Pinthong Dynoed his car with the Bosch plugs, he drove with the plugs for a while then redynoed to find a power loss. He then reinstalled some old 60k mile OEM plugs and guess what? The power came back and the weird driveabilty issues he was experiancing but did not attibute to the Bosch plugs instantly disappered. If you remember, Chris was your big supporter in your efforts to prove my advice for using OEM plugs wrong. Well he admitted to me that he was very wrong but never bothered to post anything about it.
As far as my 400 hp creations being undrivable, they are well engieered street machines, daily drivable calm and easy to manage and mosters when given the spurs. Ask b15sentra.net webmaster David Evans, or SCC engineering editor Dave Coleman who have both driven the Disco Potato B15 that I helped build and let them tell you how tractable and friendly that motor is and what a dream it is to drive, even in bumper to bumper traffic. Ask Ryan Besterwich, Ron Avacedo, Jay Hassigner, Aaron LeBeau, Mike Mager and many others if my creations are tempermental moody machines, they will tell you no.
I have probably had my hand in 70-80% of the Non -Stillen performance parts currently out for the Sentra family from mild to wild, I don't see how you can say that I only have experiance in extremes. If you ever do ventrue out and mod your car, chances are that I was consulted in some aspect of the part you are installing on your car. From an AEM intake to the JWT balance shaft removal kit, the F-Max turbo system, to a Hotshot header, GC coiloversand even a JWT camshaft, I had a role in bringing it to market. I am not a promoter of extremes, I understand all aspects of the industry from mild to wild.
Anyway my opinion are much less conjecture than yours are. Yours are pure opinion and conjecture. Mine arte based on actual happenings and experiance, lets leave it to the readers of this thread, who are you gonna belive?
How come you don't post on the se-r mailing list anymore? I miss you
Originally posted by Altim8GA Ok, so some belive that this causes problems after a few years, and some belive that this causes no problems what so ever. I want to see some posts on other forums before I continue with this. Please continue to weigh in. I'm lernin sumtin.
Please visit the Performance forum over at b15sentra.net you'll find hundreds of posts on this very subject. Also remember that the b15 sentra (se-r, spec-v) uses our engine.
Originally posted by morepower2
The problem I have with your arguments is that your opinions are simply opinions basied on conjecture with no experiance...
Mike, if you're gonna play the whip-it-out-and-let's-measure-game then of course as a general rule I defer to your expertise. But there are times such as this that you let your street- and track-racing mentality get in the way of what makes good long-term sense for a guy who wants to add a few horsepower to his ride without compromising long-term reliability, NVH or value. I'll say it again: Removing the balance shafts in an average street car is a bad idea for all the reasons I've outlined numerous times in this thread.
Yanking them in a track car, however, is another matter entirely and no doubt has little impact on reliability. But while the statement that track miles are substantially harder than the worst stop-and-go traffic imaginable, neither I as an "armchair engineer" (I like that) nor any competent real engineer would make the leap that if a shaftless QR can run 500 miles on the track without issue, then Jane Grocery Getter should obviously get 150,000 miles out of the same setup. They're apples and oranges, my friend, and you know it. And I'm only addressing the latter situation in this thread.
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You on the other hand have nevber been within 300 feet of a QR with no balance shafts I bet.
I'm betting you've not been within 100 yards of a Siberian tiger, but that doesn't mean you don't know what to expect: It's white, fuzzy and will bite your damned arm off if you get too close. I fail to understand your point.
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I have been involved with modding several QR's for racing...
Mike, tell me something I don't know. You are an expert in this area. There's no need to keep expounding on your resume.
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Your opinions are conjecture, mine are from actualy doing and experiancing, especialy on the QR25.
Interesting. I stand corrected, then. So how many 10-year-old QR25s without balance shafts have you worked with? How many miles did they have on them again?
Sounds like conjecture to me.
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I remember the spark plug argument well! You are my favorite guy to argue with.
I'm flattered. Right back at you!
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If you remember, Chris was your big supporter in your efforts to prove my advice for using OEM plugs wrong. Well he admitted to me that he was very wrong but never bothered to post anything about it.
This also is interesting, but since Chris isn't here and neither I nor anyone else that I occasionally converse with on the mailing list has ever heard of this, I think perhaps we should let it lie. Take a similar line of reasoning into a courtroom and you'd be shown the door even before you took your seat.
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As far as my 400 hp creations being undrivable, they are well engieered street machines, daily drivable calm and easy to manage and mosters when given the spurs.
You know the point I was trying to make, Mike: That most enthusiasts want to spend a few hundred bucks in simple bolt-ons to free up an additonal 10 to 20 horsepower in most cases. They don't want to void their warranties, they don't want to go through complicated and detailed installations (or removals in the case of balance shafts) and they absolutely want to retain the full value of their investments. Show me a lowered, winged, bedecked lime-green import equipped with the JWT catalog and I'll show you a worthless trade-in that the warranty manager won't touch with a ten-foot breaker bar.
You've always had a difficult time seeing the concerns of the first-time or low-end modder. You're an engineer with substantial racing and development experience; you're on the other side of the looking glass. When I see posts such as yours advocating balance sh
