M45 Mods

[NightWatch]

Has anyone on this board ever made any performance mods to the M45 and been truely happy with the results? Long-term? If so, please share Becuase it appears that most posts on here indicate disappointment or failure at trying to turn the M45 into a real beast.

[fiveliterbeater]

Has anyone on this board ever made any performance mods to the M45 and been truely happy with the results? Long-term? If so, please share Becuase it appears that most posts on here indicate disappointment or failure at trying to turn the M45 into a real beast.

well according to your profile you have an M35; why so interested in what mods work for the M45?

...but anyway, answering your question, I've done the TB bypass, KeninAZ's intake mod and a 2.5" inch custom X-pipe and my M45 is a totally different car (when i floor it of course) and i'm extremely happy; ......on the other hand you have old timers who believe that there is nothing you can do to this car to make it go faster. no matter what you do ( and they know who im talking about) , mods are a waste of time and money. gotta respect their views so in the end, i guess you just gotta see it to believe it......or in this cause, DO it to believe it.

[ken in az]

Has anyone on this board ever made any performance mods to the M45 and been truely happy with the results? Long-term? If so, please share Becuase it appears that most posts on here indicate disappointment or failure at trying to turn the M45 into a real beast.

Me, and yes my mods work, give more power and better fuel economy. Coupled with the shift kit I'm just waiting for uprev so I can tune for boost!

[GJEMD]

I'm one of the old timers. Hopefully Ken realizes I for one was a tuner in my younger days. But then it required changing camshafts as well as headers,and a high rise manifold. The objections to the purported MODS of the M45 are "seat of the pants" and exhaust note verification. If you search this topic you'll find a number of very scientific based explanations that the FACTORY did a jam up job and little is left to do other than "race prepare" this engine. Whatever increase in street HP left is in the ECU programming.

[NightWatch]

Why am I interested? Because I'm a contributing member of this forum. I read everything that is posted here whether it be for the M35 or the M45. As of late I've seen a lot of posts expressing disappointment over both the performance of the M45 and the lack of performance enhancing modifcations and it has caused me some concern. Some of these post have reflected very poorly on the Infiniti name in general I really like Infiniti as a brand and I think for the price their quality cannot be surpassed. I've owned 3 Infiniti vehicles so far and I suspect that my next purchase in a couple years will be another Infiniti.

I was performance tuning cars before a lot of you were out of diapers. I've made LT1's, LS1's and LT2's scream and have a few awards to show for it... so I understand performance tuning. So generally when performance tuning goes bad one of two things happened. Either the mod was done incorrectly... or the mod was inappropriate for the vehicle engineering. I would simply like to know and have the rest of this forum's membership know which it was... In addition, we all like to hear success stories, we all like to know what mod's have been done and proven to work - especially those that are new to this board and new to performance tuning. In generally I'd rather see the Infiniti name praised rather than bashed...

Thats why I asked the question I did.

[szh]

......on the other hand you have old timers who believe that there is nothing you can do to this car to make it go faster. no matter what you do ( and they know who im talking about) , mods are a waste of time and money. gotta respect their views so in the end, i guess you just gotta see it to believe it......or in this cause, DO it to believe it.

Um, no. I am sure that some things do help. For example, I believe that adding a supercharger or turbocharger would make a significant difference indeed! So would changing the differential gearing on the M45.

The problem is that most of simple changes don't affect the car much and usually hurt some aspect of the overall performance. At best, some of the modifications restore some of the losses due to the car not performing at its peak in the first place.

Plus, and this is more common than you would think, many changes have no real effect, but it is only natural to hope/pray/think that they do and fool yourself into believing it did. That is only human and natural.

Some years ago, I spent a long lunch with some automotive design engineers and engineering managers at two auto manufacturers - some were old-timers, who had worked on their oen personal muscle cars. One lunch topic was on modifications that people could do to cars. Some of the disjointed things I remember (not exact words, since I don't remember those!) were:

1. Cars made today (particularly in the past ten years or so) are not the same as those from the sixties, seventies and even eighties or nineties. They are engineered to perform as complete interconnected systems to a set of design requirements and manufacturability. The engine management processors talk to the transmission processors, take readings from sensors (air flow sensors, knock sensors, engine rpms, etc., etc., etc.) all around the car, and the processors make adjustments from all kinds of different inputs. If you change one of the variables, you have to examine the effects on others because "things may fail".

2. The car also need to meet a large number of governmental regulations if the car is to be sold in the US (and many other countries too). If you change one set of variables, without evaluating or compensating the effects on others, the result can often be a failure of one or the other parameters. Yeah, a change may not affect whether the car passes the specific design requirement or government regulation, but it could make it borderline. What might pass on one car may fail in another. It may not be possible for the mftr to make a change and still have manufacturability in high volumes.

3. A change you make to a car that works in one market may not work when you move to a different part of the US, with a different climate (for example, cold conditions in winter).

4. If you turbo-charge a car, you should make appropriate changes to the engine and transmission firmware, and beef up the transmission if you want the car to be drivable and and/or the engine/transmission to last a while.

5. Unlike older engines, most engines today generally are operating at close to what is possible to eke out of them. Short of turbo-charging, you will not get any significant change in performance.

6. Most of the after-market "power boosters" don't work. As one of the engineers put it: "snake-oil". One guy said that they tested some of the products (that might have some real engineering) on the market, and did not find anything of value.

7. After-market "grounding systems" that bring wires back to a common ground point usually don't help and may actually hurt - given that most electronics today contain active grounding electronics. Plus, they may bypass safety circuits that are there to prevent damage due to voltage spikes, etc.

8. Manufacturers do cut costs on many aspects of the car, so using better (perhaps more expensive) parts may be a good thing to do. The examples that I recall being mentioned were oil filters and tires.

9. A dyno reading taken in the morning will give you different readings than a dyno reading on the exact same car in the afternoon. This difference can sometimes be larger than the "performance boost" quoted by many of the after-market stuff!

So, I also asked them what they would recommend people do to cars (for performance improvements) given the opportunity to change anything :

1. Turbo-charge the engine. And "adjust the programming" to correct for drivability problems.

2. One guy mentioned "put on racing slicks" ... but you had to be in dry country.

My bottom line: I don't discourage people from making mods, as long as it makes sound engineering sense and the outcome may have a possibility of working. However, some may be detrimental (based on years of experience of people here) to the car - whether it be short-term or long-term. So, us old-timers do tend to speak up and note those.

Regardless of which, ultimately it is still the choice of the owner of the vehicle to do what they want!

Z

[ken in az]

Everyone has been really happy with the exhaust systems out there. Even just the axle back systems have positive response.

The intake system on the M is very good from factory. One of the best I've seen, but to say it can't be improved upon is just not true. One of the things holing the M's intake from being modified is because the MAF sensor is calibrated for a set determined diameter intake tube. The diameter it is calibrated at is approx 81mm or 3.19" or 3 3/16ths inch and unfortunately you cannot buy tube in this diameter without having it specially made to order which makes it expensive. If the stock MAF is placed in a tube that is smaller or larger in diameter than stock it will then loose it's accuracy reading the wrong amount of airflow into the engine.

The injen says it uses MR technology to maintain accurate air fuel ratios. That is really just BS because if you look at their intake, it uses 3.5" tube but then "necks down" at the MAF for ~ 3 inches or so right where the MAF is to simulate the stock intake tube diameter.

My intake is almost exactly the same as an equivalent JWT POP charger except I actually utilized the stock intake tube as to not throw off the calibration of the MAF sensor. I also utilize the Amsoil Nano filter which is a Dry filter media designed to out flow cellulose filter media and the other oiled type of filters on the market. I believe AFE has an equivalent filter media which is just as good if not better than the Amsoil.

My intake does have it's drawbacks - #1 it pulls in hot air from under the hood. This isn't so bad at freeway speeds because the stock over radiator intake scoop does flood the under hood area with cooler air, but during stop and go, it does suffer from heat soak and you can definitely tell it looses some. I have placed a heat shield in the area to act as a heat barrier which does help out a lot, but is no where near optimum. I'll be adding/building a fiberglass enclosure to seal off the intake from the hot under hood temps which should help tons.

One other item that the Injen suffers from is the CAI configuration uses such a long tube all the way down to the bottom of the fender. An intake that is that long will inherently loose low end performance but gain in the top end. If you check any other car forum they will report the same thing for all long snout CAI intakes regardless of the manufacturer.

I wish that Amsoil or AFE made a factory dry filter replacement element to just stick in the stock air box. That would be the cheapest upgrade that would actually work the way the factory intended it to. K&N makes an oil filter drop in replacement, but I would never use an oiled type filter in any car I own.

[ken in az]

Um, no. I am sure that some things do help. For example, I believe that adding a supercharger or turbocharger would make a significant difference indeed! So would changing the differential gearing on the M45.

The problem is that most of simple changes don't affect the car much and usually hurt some aspect of the overall performance. At best, some of the modifications restore some of the losses due to the car not performing at its peak in the first place.

Plus, and this is more common than you would think, many changes have no real effect, but it is only natural to hope/pray/think that they do and fool yourself into believing it did. That is only human and natural.

Some years ago, I spent a long lunch with some automotive design engineers and engineering managers at two auto manufacturers - some were old-timers, who had worked on their oen personal muscle cars. One lunch topic was on modifications that people could do to cars. Some of the disjointed things I remember (not exact words, since I don't remember those!) were:

1. Cars made today (particularly in the past ten years or so) are not the same as those from the sixties, seventies and even eighties or nineties. They are engineered to perform as complete interconnected systems to a set of design requirements and manufacturability. The engine management processors talk to the transmission processors, take readings from sensors (air flow sensors, knock sensors, engine rpms, etc., etc., etc.) all around the car, and the processors make adjustments from all kinds of different inputs. If you change one of the variables, you have to examine the effects on others because "things may fail".

2. The car also need to meet a large number of governmental regulations if the car is to be sold in the US (and many other countries too). If you change one set of variables, without evaluating or compensating the effects on others, the result can often be a failure of one or the other parameters. Yeah, a change may not affect whether the car passes the specific design requirement or government regulation, but it could make it borderline. What might pass on one car may fail in another. It may not be possible for the mftr to make a change and still have manufacturability in high volumes.

3. A change you make to a car that works in one market may not work when you move to a different part of the US, with a different climate (for example, cold conditions in winter).

4. If you turbo-charge a car, you should make appropriate changes to the engine and transmission firmware, and beef up the transmission if you want the car to be drivable and and/or the engine/transmission to last a while.

5. Unlike older engines, most engines today generally are operating at close to what is possible to eke out of them. Short of turbo-charging, you will not get any significant change in performance.

6. Most of the after-market "power boosters" don't work. As one of the engineers put it: "snake-oil". One guy said that they tested some of the products (that might have some real engineering) on the market, and did not find anything of value.

7. After-market "grounding systems" that bring wires back to a common ground point usually don't help and may actually hurt - given that most electronics today contain active grounding electronics. Plus, they may bypass safety circuits that are there to prevent damage due to voltage spikes, etc.

8. Manufacturers do cut costs on many aspects of the car, so using better (perhaps more expensive) parts may be a good thing to do. The examples that I recall being mentioned were oil filters and tires.

9. A dyno reading taken in the morning will give you different readings than a dyno reading on the exact same car in the afternoon. This difference can sometimes be larger than the "performance boost" quoted by many of the after-market stuff!

So, I also asked them what they would recommend people do to cars (for performance improvements) given the opportunity to change anything :

1. Turbo-charge the engine. And "adjust the programming" to correct for drivability problems.

2. One guy mentioned "put on racing slicks" ... but you had to be in dry country.

My bottom line: I don't discourage people from making mods, as long as it makes sound engineering sense and the outcome may have a possibility of working. However, some may be detrimental (based on years of experience of people here) to the car - whether it be short-term or long-term. So, us old-timers do tend to speak up and note those.

Regardless of which, ultimately it is still the choice of the owner of the vehicle to do what they want!

Z

I agree with everything that was just said with a caveat - the racing slicks - lol

These cars don't even spin the tires at the track Stock and modified. These cars need programming to remove the WOT restrictions for traction to be an issue. On the street yeah they can spin em, but not on a racing surface with VHT applied.

I have a theory, and probably one I could never prove unless I talked with a Nissan programming engineer, but I believe that the brand new - out of the box - 2006 model year sold in 2005 had a much more aggressive ECU tune than what is in the cars now. Every review I've read and watched on the web circles around the fact that the car has a tire spin problem or is aggressive off the line. My bet is that Nissan changed the tune on the ECU to make it less aggressive which is sent to all the dealerships to be downloaded into the car anytime it is in for service. I can literally feel the throttle being held back when I first depress the pedal from a stop.

One thing to back up my theory is the mph in my trap speed does not reflect the E.T. The E.T. is slower than one would expect with almost a 100mph trap. Also my 60ft time is lousy considering I have "no tire spin" on the launch.

[szh]

- the racing slicks - lol

He was joking when he said that. But, he did mention tires as something to look at.

Z