** This thread is in NO WAY a reason not to buy an HO alternator, if anything it is an insight on whether or not you should. The deal that R/TErnie has going is a great deal. This thread is to be looked at as an education of our electrical system, use it to decide whether you need to upgrade yours.**


Ok so I have been thinking about this a lot lately and have come up with some questions. I want to collectively put together a list of products that individuals and/or shops are running and the specified volts and/or amps for each. From there we can add up the total estimated amperage needed to determine whether or not a high output is needed for each individual. No more guessing...

- What is the actual amps used on a stock evo 8/9?

- With that number, what capacity is the stock 90A alternator operating at? Safe capacity before leaving "efficiency range" is 72amps

- How can we, as a group interested in this product, calculate the amount of amps that our car is drawing?

- Do you think that the main source of voltage issues stems from swapping to a 12v mini battery instead of sticking with a full size battery? I mention this because it always seems to be a debate, 12V vs. 14V.

- Will running an alternator double the stock amperage be harmful towards the other electronics (i.e. starter, 12v battery, etc)?My personal answer to this is most likely not since the car only draws the amps needed but I wanted to discuss it anyhow.

- Why upgrade the alternator when you're not updating the rest of your electrical system?

Ok now that I have your attention, let's begin the accumulation of information and debate!

Here is a list of parts that most of us use in our cars:
Fuel pumps (single and double pumpers
- Buschur Double Pumper - Roughly 32 amps using both pumps
- Walbro 255 16amps modified for high flow
- Full Blown
HIDs
-
Aftermarket radiator fan
-
Additional gauges and sensors
-AEM wideband
Electric water pump Around 20 amps
-
Stereo
-Oem
Injectors
-ID1000
-ID2000
-FIC 2150
Coil on Plug ignition system
-Buschur 30 amps
-Sparktech

And anything else you can come up with. As we collect information I will update the first post with useful, factual information.

 

I already gave you my .02 at 7 am this morning after a drinking nite but who am i?

 

It would help if we knew what the Walbro 225, for example, drew at WOT. IIRC, it's several amps, but I'm really not positive at this point. A double-pumper, obviously, will have higher demands. Just shooting the breeze, it's not unreasonable that a car that isn't stripped down and that's tuned to the max may need more juice at some point. Interesting discussion.

 

Fjf, exactly... I am looking to collect and discuss data to eliminate guess work.

 

I will be buying the alternator as I run pretty much everything you said as well as a 1500 amp stereo system. But what I am worried about and will ask R/T Ernie is the pulley set up. Since my car will also be pushing around 850+ hp and revving out to 9K what pulley do I need to I can use everything that way I currently do. So do I stay with the stock pulley or move the new one they also had designed for my setup.

 

How i see it is if voltage is 14.5 at cruise, but 13 at wot, the alternator cannot keep up. Its that simple. If the ignition and fuel pumps can keep up at 13v, then you dont "need" to upgrade but it sure wont hurt.

 

Good point but just because they're keeping up doesn't mean the alternator is past it's operating capacity which is rated, I believe, 20% less than the actual alternator amperage. In this case it would be 72 amps.

 

Without taking this thread OT and discussing the rationale for this, the car audio world wants you to wire everything for as low a load as possible, as such, drawing as much current from the electrical system as possible. Don't do that!! Choose sensitive drivers that don't need a lot of power. With a sub, under no conditions wire the thing for less than 4 Ohms, so choose wisely. This can take you from an alternator/battery upgrade and its associated heavy-gauge wiring, along with a big amplifier or two, to being perfectly satisfied with the stock electrical system running a small, quality amp. All this solely driven by one's equipment choices and a lack of audio ignorance.

 

isnt that this?

https://www.evolutionm.net/forums/ev...lternator.html

 

Upgrade your power and grounds with good quality wire, running to everything in the system, starter, battery, fuel, and anything else that has more draw on it and the problem should fix itself. I mean I will argue this till the cows come home. Its the fact that you can upgrade wireing to help create better draw to everything will help more then going out and buying un needed parts. The more less, the less resistance something has to it the more it will keep its current voltage and is cleaner power. If you were building a car from the ground up yes absolutely I would rerun everything I could to the things that draw the most power and make sure they have the best power, grounding points with proper size wires for the current amp draw. I mean remember 3 years ago I melted my walbro's in car after I rewired them? Sure have a good ground, good power and me being stupid and not thinking hey dumb *** this is gonna draw 20 amps per pump instead of doing it proplerly. What happens? Pumps, lines get way to much current needed and melts everything.

I mean if you took out all the bull**** in our cars and ran nothing more then you needed to run the stock alternator would be plenty. I mean no acd stuff if its an 05, no yaw this and that computers, no radio, no misc odometer stuff, no fancy this or that the stock one would be more then enough. Now people are gonna say well the stereo guys do it. Yeah cause half of them have to have a powerplant big enough to supply a city in most cases and or 2,3, or even 4 batterys in series. So with that said an alternator in a compitition vehicle that will do 190 amps has to be there for the vehicle to remain driveable.

Ok so mini battery setups. Is this a good idea? Not in my opinion being sure it saves you a few extra lbs but its only a 12 volt setup. I am sure many of you includeing myself wonder why we put these things in our cars and a few days goes by of not driving the car due to whatever reason and the damn thing is dead. Well yeah there not made for a 14.7 voltage system. Stock alternators will handle them being they are sending more power to the battery thats needed and this kills the batterys. Now if it were a setup for race only with no extras on the car that many of us have for enjoyment and ease of use, then I can see it being ok. Point is the more in the cars the less these thing perform.

Now lets look into well the v8 guys do it this way. Sure they do 99% of the time they build cars with whatever in them you have to look at it this way. Most cars have 50 to 75 amp even 90 amp alternators. When your running all your whatever, fuel injection, computers, afr stuff for turbo cars etc, your gonna use more power being the there is more to it. That is why they can order premade wireing harnesses with good quality material in them to help with power loss. When it comes down to it ohms law is your friend. Study it, learn it and you will be supprised what you can find out.

 

I tried engaging you in a PM over the setup due to your knowledge and you kinda blew me off two weeks ago.

 

Yes sir, that is a great deal. This is to merely learn/educate through collective knowledge for those who think they need or want a HO alternator. I'm trying to collect data from others while compiling my own to eliminate the guess work out of amperage and the need for an upgraded electrical system.

Bryan,
Yeah this is what we were talking about earlier...I am determined to gather hard data about the "oem" amperage ratio vs. modified cars with many electrical add-ons which draw more.

 

How dare you mispell my name jhonny. Anyways yes it is what we talked about and it wasn't directed twards you just general info that I am passing along. I tried to go to the mini battery thing at dinner, and stupid cell service quit on me and I lost everything I wrote. Basically what you can do is you can tell what amps are used just by your fuse box as a general guide. But as I know thats not everything. To truely do this testing and thinking that you wanna do, you mine as well start out with a bare car (theoritically) and say ok I need this, this, this and this and that to make the car run. Find out what kinda voltage is needed and then start adding on. You will be supprised on how little the car needs when it is stripped down to bare nothing, but yet at the same time our cars have so much in them from the factory all the extra goodies are added and its a unfair compairison.

Now in your case your running an electric water pump for whatever reason you decided on, instead of looking at it as being no power to be driven to it from the factory, now your adding more power to the equasion. Anything else you add that you think is a good idea rather it saves weight or not, you have to think about the extras you will need power wise if it is electric and make sure that is in fact part of the equasion.

 

Maybe I can get R/TErnie to chime in with his technical expertise. I'm hoping to get some guru's who log EVERYTHING so the data will be easier to come by because surfing each site inidividually looking for specifications sucks..

 

I am sure he whill chime in on for it being thats what he is tring to do duh!