Plus his diff cooler fan, trans cooler fan, electric water pump, etc, etc.

Just concede man, :lol:

Even worse!

I'll get the alternator charts for our alternator then hop on the dyno.

$50 says there's an increase in the calc load at cruise once all the accessories are turned on.

So far I see no evidence that I have current problems..the Bat+ is 13.8-14.3 driving and the batterys last fine. That's even with 4GA battery relocation to trunk and the potential voltage drop from that

Suppose I will have to put a current clamp on the main line and see what kind of amperage I am drawing.....

In calculated load?

We are talking about 2 different things..I am talking about Current Draw and Shady is worried about calc load increases......

Load will just burn a bit more gas...I already have a big problem with that ;)

Yes, if the calc load goes up then we know something is causing the engine to work harder.

If we remove all variable from that equation ( bumps in the road, elevation, pressure, etc) then we can only assume that the alternator is causing the engine to work harder.

If the load stays the same then we know the alternator is not working harder and is supplying the same amps as it was prior to the increase in load from the system (turning on lighting, radio, blower)...

Its a fairly simple test.

And about as accurate as eye surgery with a machete ;)

His entire theory is that the added amp draws are detrimental to the performance of the car and that there is a potential to overtax the system and cause issues. My point is that it would take a lot of shit to cause performance issues and that the stock alternator can handle aftermarket fans, pumps, etc. just fine.

It's really not an argument since it has been proven by you and many others though. The only person I know of to overload the factory charging system and need a more robust alternator was running air compressors for an air ride suspension and a crap ton of screens, actuators, speakers, amps, etc. etc.

I am not doubting that our system is capable of handling the hz/amp/volts of all the electronics.

I am saying that it adds load which = less HP more fuel consumption.

When you have a track built REW with a fatty turbo none of that matters. LOL

Now you are changing your stance, your whole point was that the added amp draw would overload our system and that is why you would'nt run the larger coolant fans, etc. You should really read the last link I posted, you just are not comprehending fully how the alternator works. I get what you are saying about fuel mileage but if you think the same car with diff coolers, etc. running will make less horsepower than without them running at the same RPM then you are wrong homie.

Not to mention the increases in power and efficiency that theoretically should be provided to the engine and drivetrain by running cooler, etc. Remember, we have a pretty serious alternator compared to other small engine cars.

This was my main point and one of my first posts.

Never said anything about overloading, just making the point that less amp draw the better.

The more amps you add the harder the alternator works, harder it works more is required from the engine.

Your still not getting it man. So you are saying my idle coolant temps would be less if I had the stock radiator fans in?

The alternator makes more than enough to supply the needed voltage for anything that you could want to add realistically, even at low RPM. And your argument initially (before this thread even) was that the RX-8's charging system was taxed as is, which is why you did not support adding additional fans, etc. My point is that is just not true, and adding fans, etc. has no negative effects. The idea that adding fans, etc. reduces horsepower is just kind of ludicrous man.

They wouldn't be less but the fans would run less.

If your amp draw is higher than the factory fans the alternator will work slightly harder. If the alternator is working harder the engine will work harder to keep the idle up.

With everything energy related there is always a trade off, the idea is to find out where you want to be most efficient. Remember Energy cannot be created or destroyed only transferred.

Now in your case, if the fans are pulling more heat off the rad than the extra load is causing you wont see any increase. It is effectively balancing the extra load. If they aren't pulling enough heat off you will see a slight increase in coolant temps which would cause the fans to run more often.

Theres always a break even point... Example, if you had one 80 amp 3000 cfm fan the engine would eventually overheat due to the increased load not being compensated for.

So if you had fans that flowed more air than stock while pulling less amps, they would run less. Reducing fuel consumption/load on the system.

Its not like 30 gallons of gas, its very minimal amounts.

I still think the factory system is taxed as is...

We have so many things pulling amperage from the system as is. adding all the gauges, sound systems etc... It all pulls amps.

Amps are the devils!

I am going to video my good box on both load readings and then turn everything on so you can watch. At idle the loads will go up slighty and then watch the loads decrease as I rev up from idle to say 2,000RPM. Then you will get it :)

...if the alternator didn't do its job right off the bat all kinds of shit would happen

This is why modern cars dont use Generators anymore. An alternator is at full voltage output just over idle.
If you put a multimeter across the battery when you start your car, you will see when the alternator cuts in and is charging at full voltage, it will go from around 11.5-12v up to 13.8-14.4v and should only vary around 1v or so when under load.
But if you load up the alternator over its current output, then you will start using up the battery's storage capacity and once you start doing that, it won't take long until you are having problems with flat batteries.
I suggest that if you are adding items to your car that have high current loads, eg - car stereo amps, extra fans, electric water pumps etc, then the best thing to do would be, calculate your total current draw on the alternator and see if the total current draw is more then the alternator amperage output.
If your total load is more then your alternator output, then I suggest that you look into a larger output alternator, and higher capacity battery.

Exactly, and to overwork the stock 100+amp alternator it will take a lot more than aftermarket radiator fans and some gauges, etc. that only draw 20 amps max at most.

did you quote me OD :)

I think at this point Shady is trolling....the proof is in the pudding...Science....lmao

http://www.singandbeseen.com/wp-cont...ther-lover.jpg

http://performanceunlimited.com/cobr...ain/img383.gif


I think you will find that as OD has posted here, the horsepower used to power the alternator is usually directly atributed to the physical size of the alternator, in other words, it takes more power to turn over a 200amp alternator compared to a 100amp one.
Try it yourself by hand, spin a 50amp alternator by hand and see how easy it is to turnover, now try spinning a 100amp one. You will see that not only is the item physically heavier, but it does take more effort to spin.
The alternator just becomes another resistive force that has to be turned by the engine.

In my own car, I run plenty of extra electrical items, eg - big amp and amplified subtube, 2 extra 6in fans on the oil coolers, 2 extra 10in fans on the aircondensor, ( air condensor lies flat on the undertray ) plus other items that don't use much power, like Hks camp 2, extra guages, gear change indicator, DVD player, etc.
I still use the factory alternator, but I have changed all my battery wiring and I use a large Odyssey battery for plenty of storage capacity.
My alternator doesn't have any problems keeping up with it all.

Rotaman

But the alt load is consistent and doesn't change with draw. It always takes 2.3hp to run it :D

Shady will get it :lol:

Power = volts x amps.

The voltage regulator regulates voltage, not current or power. Except perhaps near idle and under extreme load, the voltage measured from the alternator is essentially constant. Zero amps @ 14v is zero power. Electrical loads from fans, lights, ignition, etc. increase the current (amps) flow, hence increase the power, hence the drag from the alternator on the engine. Draw 746 watts, and it takes 1 hp from the engine (ignoring losses). That's about 50 amps at 14v. There are of course significant losses (the drive belt, battery, wires, motors, etc all get warm.) Figure at least a 50% loss.

A couple hp from a ~200 hp engine doesn't sound like much, but the engine is seldom at full output. A modest steady cruise requires only ~30 hp, and then a couple of hp represents a ~7% power loss and a ~7% reduction in fuel economy. It's one reason new car makers are trying to cut electrical consumption to get better EPA ratings. (EPA tests are done with daytime driving lights off - even if the model is only sold with them - since DRLs are not required by law.) LED lighting and Class D stereo amps are coming on strong for this reason.

Alternators are rated by maximum output. If the car is drawing 50 amps, there is little difference in the power required from the engine between a 100 amp alternator and a 150 amp alternator; both are producing 50 amps. There is some difference though. Weight, power to run the field coils, and cost argue against having overcapacity in the charging system. Plus, when accelerating, one has to deal with the increased rotational inertia of a too-big alternator.

Ideally, as done with some hybrids, one would do most of the charging when the engine is slowing, using the alternator as a form of engine braking when coming to a stop. Then, when accelerating, the alternator is taken out of the system to allow more power.

Considering the gas-slurping nature of the Renny though, an additional fan or two isn't going to make much practical difference.

YMMV.

Well I had found a mizu radiator on amazon and bought it. Couple of hours later the company called me and said I needed to cancel the order because mizu discontinued it for the rx8. Which would explain why I can not find it in stock anywhere...

They guy on the phone recommended Mishimoto, and said they are the same radiator.... This is true? I could have sworn I read on here to stay away from that brand....

He also recommended Koyo....


Ideas? I'm going to just go ahead and replace both fans and rad at the same time to be done with it. But would prefer to get away from the plastic radiator...

I would go with Koyo over Mishimoto. Koyo makes OEM stuff and the Knightsports radiator. But there is a brand new OEM radiator for sale locally her for $150.00 if you are interested.

This one right?
Thanks for the offer on the oem, but I hate plastic radiators! :lol:

The pic is wrong but yeah that is the one.

OEM is still the best bang for the buck radiator out there...

I wouldn't mind oem if it was metal. I always seem to have shitty luck with these plastic radiators...

Well stop messing with it! If you never touch it I guarantee it wont break :)

But... But, the nipple of doom.... :scared:

I still don't know how I managed to change the nipple line without breaking it, but managed to crack the upper hose neck instead.... :wallbash::wallbash::wallbash:

Yeah the Koyo is not really any better than the OEM IMO but the nipple won't break off, that is for sure. But I am sure the OEM is plastic for a reason.

Yeah, and now I'm reading on the Koyo radiator "May require modification due to increased core thickness.". That sounds like fun...



The only reason I want to upgrade is to get away from the plastic. Car is never tracked. (Maybe one day, for fun.)

I guess I would get a good solid 6 years or so out a new OEM one.

Now I'm more undecided than ever...

It may not fit perfect but you will make it work, it is pretty obvious when you get in there. But buy some proper large square foaming to seal it up nice.

I never knew a single RCH could be split into so many tiny strands.

Congratulations.

And my adventure begins. :)

^awesome. I just ordered the same one. :)

Fans just came in. Went go buy some coolant and oil. Just need to get the foam. Should be installed in about a week. Really liking the fans, they're surprisingly heavy.

Ah you bought the higher CFM setup, cool.

Same fan pack as me. No issues with fitment here.

I'm assuming the little "clips" (one blade on each fan) are for balancing the fan and I should not remove them?

My only last question is mounting the fans to the rad. I can get 2 of the brackets on the driver side to work, but not on the passenger side. Should I just use those "universal" mounting zip tie things. Sorry I forget the correct terminology, It's basically a large zip tie with square ends, you pass them thru the rad and the mounting hole of the fan shroud.

My blades had no clip things. No need to use the brackets. I used metal rad pin mounts. The metal ones are not super easy to find but i just did not trust the plastic ones.

Ummm. I have tons of foam... cut to fit also they are huge!!

I figured I would do it at my parents place since I wanna do a bunch of other stuff at the same time, plus I'll probably be doing it Wednesday / Thursday. I'd gladly take the help though.

OKay, well I have styrofoam and regular foam, whatever you want to use. You can grab it whenever. I may be in kenner at the mall or something and drop it off for ya!! I won't get any texts as I got my phone wet and it doesn't work right.

Just finished installing it!

Can't wait to hit some summer traffic to she how she does. Sounds like a damn tornado under there when on high!

Thanks for all the info everyone. Took about 6 hours solo with cool down time. :cool:

(btw, as usual with my luck they only had one roll of black foam left, so the other 2 were white. I used the black for the bottom.)

Looks Great~!

Good job man, you will be impressed, even my lower CFM 410's work awesome.

Thanks! Next is motor, flywheel and clutch. :)

Update:
 

Did some torture driving....

Dash reading 95*F AMB

Fans are set 186/188/194 (30mph)

Sustained High speed/load driving; A/C On - 205*F, A/C Off - 198*F

Heavy Stop-N-Go traffic (Aggressive Driving); A/C On - 201*F, A/C Off - 194*F

Light Driving, Light Traffic; A/C On - 192*F, A/C Off - 186*F


I am satisfied, bring on the heat. :cool:

Good write-up the pics are great! One question though, I am having a problem finding which wires go to which wires. I have read (through exhaustive searching) that wire colors are not always the same. I seem to have the same wire colors as you do(coming from the harness and off the fans) which wires go with the red and black wires off the harness? The only thing I have managed to scrounge up says that the red from the harness is actually a ground.