Never assumed, Noticed I stated what equipment and vehicle was used for this thread

The Unit is always on, you will only hear it on when the car is sitting in a long idle, or after you park the car and drive off (you'll hear it for a few seconds and then it'll slow down to it's desired range).

Why you don't see it sucking out 20whp is because you are very acustomed to the fan clutch. (Go from E-fan to fan clutch and you'll be like It's a difference.

Additionally why you don't see the ET's differente is solely because the fan clutch is VERY consistent. It works 100% of the time (as long as it has no failures), regardless of what range it is at.


The fan is always engaged, ALWAYS. Not 60-80% because you are traveling therefore causing the temperature to drop. regardless your radiator temperature will be in the 150-170(depending on outside temps and rate of speed you are traveling, as well as other variables like wind direction) NO DOUBT about it.

If you believe I am truly wrong, please provide Physical DATA to make a valid post.

How so?

ever heard of Newtons third law?
"For every action there is an equal and opposite reaction."

It's a FACT, not an opinion.

Grab a bowling ball, throw is as fast and far as you can possibly throw it. (not roll but throw)

Now, grab a golf ball and do the same thing.

Which one is going to travel a further distance before it hits the ground?

The Golf ball, Why is that? I'll let you take a guess.


Weight plays a role, there is a reason you are changing your tires/wheels from 18's to 15's. Not only gearing, but weight. Look at your garage you even claimed the weight... You're not making obvious sense here Dave. You believe a lighter pulley is not going to make better performance, but you change your wheels for a beneficial performance gain.

Yes, one of the best ways to test this out is to actually do before and after Dyno's but all in all, math is math and it never lies. You do have to account for variables. But at the end of the day, you RARELY dyno with your hood closed. and thats then the temperature differences will REALLY make a difference with the fan clutch.

Refer to my post above about weight and pulleys.





Sorry it's taken me a while to respond been a bit busy. With all honesty Dave, I know you don't jump on trends. I can see you check results and validity before moving forward with something. But all in all if you strongly believe my results are inaccurate Please for the sake of EVERYONE provide DATA, not just IMO's. I appreciate your opinions sir, but prefer I prefer your wisdom.

 

I understand that the fan is always somewhat engaged. I'm not debating that. What you're not understanding is that the fan is putting very little drag on the accessory system when the fan isn't fully engaged. The pulley that is attached to the fan weighs .4 lbs. I'll take your word that the entire fan assembly weighs 8lbs. As you've stated, there's a degree of slippage from the fan assembly to the pulley which it's connected to. It's basically around 20% slippage. If it didn't do this, the fan engagement would be pretty aburpt. So, under normal conditions, the pulley is only having to spin 20% of the weight of the fan, not 100% of it. It's basically like adding ~1.5lbs of weight to the pulley. When the fan engages, it's a full 8lbs.

Then there's the distribution of the weight of the mechanical fan. It's centralized closely around the hub which greatly reduces rotational inertia. The further weight is from the hub, the harder it is to accelerate and decelerate the object. The same thing basically applies to larger wheels. Larger wheels have a more weight further from the hub. This impacts acceleration, braking, turning, and suspension response. This physics fact is why lightened pullies are such an absolute waste in terms of performance. It's a 6" pulley and is extremely easy for the crank to accelerate. Removing 6lbs from the pulley has hardly ANY performance impact. Like I said, I tested this very part on the dyno and on the strip. Lightened pullies are a myth. Period. There are 3rd party dynos on this site and my350z showing UR pullies gaining 0 to 2hp. That's it. Nothing close to the 6 to 8 whp gains UR touts.

Like I said, someone has already done a before and after dyno of the e-fan conversion. Unfortunately the dyno graphs are longer there, but you see my commentary regarding the lack of power gain with the conversion. Many others agreed with my stand. If this setup truly gained 20whp, the gain would have been very obvious on this dyno. The before and after dynos were literally mirror images until 6300rpms where the dyno reading started getting screwy. Regardless, there no measurable gain below 6300rpms. Read the entire thread.

https://g35driver.com/forums/g35-sed...o-results.html

Like I said, the 03 cars with the mechanical fan meet or exceed the performance of the e-fan cars. I've been to the strip numerous times and I'm right there or exceeding the performance 04+ G sedan 5ATs that are getting the same 60 foots and have similiar mods. My friend's 03 sedan with the same mods as myself was seeing the same exact performance so it's proof to me my 03 isn't some freak. If the e-fan conversion gained 20whp, that easily sheds another .2 seconds and add 2mph. That would make the 03 cars the quickest 1st gen Gs out there, bettering the Revups. I'm not buying it.

 

Here's more information to back up where I'm coming both with regards to mythical gains of lightened pullies and the e-fan conversion. The vehicle in question is a 450whp SVT Lightning. In the article they swap on a lightened accessory drive pulley associated with the supercharger and they replace the 8lb thermo-static mechanical fan with a e-fan.

http://www.svtperformance.com/forums...ing-power.html

Cliff Notes

1) They do a great job of trying to maintain coolant temps through the runs.

2) The pulley has absolutely no gain.

3) The e-fan gains 6whp and 4rwtq.

So there is a gain, but nothing remotely close to the 20whp you're claiming. Secondly, this is a 450whp 5.4 liter V8 blown motor and the fan on this truck is huge compared to our smaller V6 fans. I'd estimate the 5.4 DOHC fan is about 30% larger in diameter than our fan. Our VQ35's make nearly 50% less power so naturally a smaller motor likely won't see the same kind of gains. Most likely along the lines of 3 to 4whp/wtq.

Even if the e-fan conversion gained 6whp, it's not going to make much difference in the 1/4 which is what I'm focused on. Secondly, converting to e-fans put additional strain on the OEM alternator. Has anyone determined is the 03 alternator is up to the task to handling the e-fans in the long term? There have also been reports from some e-fan users of inconsistent e-fan operation and suspicisions that the fan might be coming on inadvertently at high speeds. That's neither good for the fan or alternator.

 

^^ looks like a good read, I will take a view at it when I get back.... far from home ftmfl

 

Plus, your math is wrong.

24 BHP @ 25% drivetrain loss = 18 WHP, not 6 which would be 75% loss.

I've done the Efan conversion, and I believe it is a very worthwhile mod. However, it will net you maybe 6-10 HP at most. You didnt consider the DRAG associated from extra draw on the alternator which does put strain on the CRANK.

My efans weigh in at maybe 8-10 lbs. No difference over stock mechanical weight either.

As for the claim of the alternator handling it - I've got 160K miles on my car now. I have had the E-fans on for some time. I lived in Phoenix the previous 3 summers to this last one here in Vegas. 4 summers of crazy heat and no problems with the alternator or the fans.

 

Answers that question.

Next question for you two, what about sound. Does the motor sound any different without mechanical fan (i.e. when it's not fully engaged)? With my 5AT and the windows down, I always hear a very light whirring from the engine bay that increases with rpm. Once above 2500rpms, I don't hear it. I've never determined if it's the fan or if it's the tranny pump. My guess is it's the pump because it disappears during the shifts.