the hotter the temp-the better it runs.

[bubzb20z]

Yeah just that. When I turn off my fans for a few minutes, the car runs almost 100%. But then with the fans back on, it will only run good at 49% throttle. I don't know if it is temp related or are the fans interfering with something. Any help is great. Its hard to start when cold, and has a severe flat spot at take off at low speed. rb2odet no codes. Thanks

[Carl H]

its the electical drain on the car, you need to upgrade the alternator...the fans are pulling too much amperage and the ecu is scaling to adjust for it (this works in theroy but in reality it kinda sucks).

[Adrian gt]

or more likely you wired your fans into a line a sensor is on?

[sxracerb25]

what kind of fans are they and do you know how many amps they pull?

[bubzb20z]

what kind of fans are they and do you know how many amps they pull?

Some auto parts slim 11'' x2. Koyo rad. I did discover that I might go back to the oem bov. I put on an hks atmospheric, and it could be jacking with my tune. (running rich) That might explain the over 50% throttle power loss, and popping.

The safc shows 13.4-13.6 volts all the time. Only a drop to 12.5-12.6 at idle. I had it rebuilt alrteady once. But I do have two rb25 swaps that I could pull one off and use it, if they are interchangable? Thanks

[Carl H]

12.5v is battery voltage, its enought to *run* the car but is no where near ideal.

[bubzb20z]

12.5v is battery voltage, its enought to *run* the car but is no where near ideal.

Will an rb25 oem alt interchange?

[Carl H]

oem rb25 is only 80a just like the 20's, best bet is to upgrade to the quest 110a alternator....you'll never have power problems again.

[Arrow]

IIRC a good alternator should be putting out in the range of 14 - 15 volts and not any lower than around 13 at idle (without underdrive pulleys that is)... I know that with the KA alternator it should put out between 14.6 and 15.6 I think anywhere above 2500 rpms, so I would assume that a RB alt would be similar - that and if you run any more accessories than stock you might want a beefier alt (i.e. sound system or whatever)

[bubzb20z]

oem rb25 is only 80a just like the 20's, best bet is to upgrade to the quest 110a alternator....you'll never have power problems again.

Ill go search, but what yearquest will work, and what all will have to be modified to make it fit/work? I struck out with both ka, and altima alts. Thanks

[disrupt]

this is just some information i remember from some electronics classes in college. alternators have the advantage over dc generators because dc generator output to depended on speed (rpm) while alternators should output the same regardless of speed in modern alternators because of a regulating system that changes the magnetic field strength using a small amount of current. So that being said there should be more resistance to spin the alternator one revolution at a low speed (idle) and less resistance at a high speed therefore producing the same current regardless of speed assuming the draw in amps hasn't changed.

I would guess if your alternator is not producing constant voltage (volts * ohms = ampere). it diode not be functioning right, brushed might be worn. I guess heat to change its efficiency (idle, low alternator fan speed).

I really have no point just rambling mainly

so if you car produces an eighty amp continuous (rms not max) draw that means 80amp *14.4v = 1150 watts. one horsepower is 746 watts. so about 1.6 hp i would guess there is about 60 to 70% efficiency to an alternator so that mean the alternator produces about 2.7 hp load on the crank. So if you use an underdrive pulley the alternater will spin slower, increase the resistance, produce the same current output but have to work harder, wear out faster all so you can save a few grams or ounzes (i have no clue no clue the weight different) but i am sure it is not more than 0.5 hp less off the crank including the radius of gyration change (where the centerpoint/average of the weight is on the radius of a rotating mass) that i garentee you can't feel anyways.

[streeteg]

whats the part number on the quest 110a?

[bmadd2402]

enough with your techno-babble jibberish. go email dave coleman.

[240wootie]

enough with your techno-babble jibberish. go email dave coleman.

i dave coleman