Got my Mechman alternator put in yesterday, pretty easy job! Still have a bit to do in terms of cleaning up the wiring, and still deciding if I’m going to trim the stock positive cable back or not; it’ll certainly look a lot cleaner if I did.

Performance of the alternator is pretty amazing! She makes 14.5V while driving, 14.1 to 14.2V at idle when hot. The factory alternator I believe started it’s life around 13.8V at idle when hot, and over the years got down to about 13.1 to 13.2V so it was time for her to go.

Happy I got this baby finally in there, car certainly seems to run a bit better. Not sure if it’s the ECU, fuel pump, or coils liking the extra power, maybe all of the above. Seat of the pants I’d say it’s up 20hp, would have been cool to do a few back to back pulls on the dyno.
In any case it’s running better without question. Thanks again Bret @ RKT Performance



Pay no attention to the blue tape, was just out of electrical tape..


Looks as well as it performs


Routed the new positive cable the best I could, it’s so damn thick it’s tough to make it bend! lol


Kept the factory positive cable in there for now and added the new cable on top


Just a simple notch in the fuse box cover to fit the upgraded alternator feed in


Stock tensioner was replaced with this manual version to support the vacuum pump

 

Just a heads up about your wire routing: it is possible for the wiper fluid reservoir lid to not seal, and under heavy braking wiper fluid can/will get to that wire and get into the alternator. Ask me how I know....

 

I did give that some thought...but I actaully don’t put anything in it anymore. I decided on switching over to a rear mounted methanol tank for my fear of leakage through that cheap OEM cap. Additionally, it could certainly splash on the header, or burst during a hard font end collision; providing some great fuel in a very bad area..

The wire is super thick, and after the install was told by Bret it was designed to run next to the fuel rail. I may remove the OEM positive cable and while doing so, see if I can make that bend. It didn’t seem to want to go that way, so that’s why I ran it the way I did currently.


I do really appreciate your insight here Njedwardz

 

Got it! Doesn’t sound like you’ll have a problem.

I’m running methanol in the factory tank and have worried about some of the points you’ve brought up. I have speakers mounted in the other places I could fit a tank so I may have to just figure out some way to reduce the likelihood of a spill.

 

Nice job. That alternator been working great for me.
You can clock the alternator so that the wires are at the bottom, or wherever you like them.
Easy to do and looks a lot cleaner.

 

how many amp?

 

Unit should be holding rock steady voltage, even when hot.

Your running the added cable directly to the fuse block, so should not be a stater solenoid connection problem, but would go back and double check your ground points, down line from the fuse box to BCM, then ECM connectors that may need to be cleaned (both positive and negitive), and since your running after market spark plug wires and plugs, any RF noise that may be driven from the coils back to the ECM that is causing the ECM to drop control voltage out of the alternator.

Bottom line, the alternator puts out way more than needed voltage even at idle from the 6 pole design, and short of other problems or an under drive pulley, the alternator itself should be holding rock steady hot or cold.

And just a FYI, but the DIC voltage is telling you the voltage of the ECM, not the dash cluster itself. So if you check the output voltage of the alternator with a voltage meter (body of the alternator as your negitive source), and the back connector under the rubber boot as your positive source), the output voltage should be holding rock steady when the motor is idling at 14.7 volt. If you noticing a decrease in the DIC voltage under say 14.4 volts as the motor heats up, but the alternator is holding steady at 14.7, the problem is from the fuse box outwards, or ground problems.

My low down with the motor idling, the A/C and radiator fan off, the lights off, will do quick checks in voltage.
At the alternator, should be 14.7 volts. At the battery, should be 14.5 volts. From the fuse box terminal, should still be 14.5 volts.
If you find that say the battery or fuse box terminal voltage is low, then use the battery ground first at the ground, then use the alternator body next as the ground. If the alternator ground voltage is higher, then you have a ground problem of the fugitive battery cable to the engine block just above the starter.

If its just the DIC voltage that is dropping as the motor heats up, then fuse box to BCM wiring, and out of the BCM to the other modules that is have a problem instead (including the other grounds down line for the modules as well).

 

I believe it’s a 160, I was advised by Bret to go with the smaller one based on my setup

 

Any tips you have on clocking it differently would be appreciated

 

Could you just used 4-gauge copper monster amp wire?

 

Very simple. Just undo the screws holding the front and back of the alternator together and turn (without pulling the halves apart) until the wires are best located for you. In my case I wanted then near the bottom as I don't like to see them sticking up like that.

 

Sac City Corvette's "BIG THREE" wiring kit for C5-6 is an great improvement also!

 

I ran my wire to the front of the eng. Behind the Rad where the hoses are...under the air bridge and connected to the fuse box from the opposite side as you.

Most would never know it was not OEM. Left the original wire there after cutting off connector and sealing the end. Zip ties it under the new wire so it can't be seen.

I found a 1/0 solid copper (stranded wire) that was 68 in long with heavy duty lugs at auto store for $48.