Well... I decided to take off my pulleys since I don't race anymore and just drive around town. They are for sale in the truck parts section. PM me if you are interested. I still have the original box and instructions, I just had the stock pulleys put back on.

 

dont tell me your back peddling cause you need more charging amps.
PUT A DIESEL ALT IN IT! 90 amps at idle VS 45/60 stocker gas alt! big D alt cost me $135

 

I have a 136amp in it. I believe stock was a 90. Your right, I did go back a little bit, but my mpg has gone up a tad with the stock pulleys back on.

 

I thought the whole point of under drive pulleys was better MPG and HP
I have been considering the swap, but not if MPG is going to go down.

 

stock was a 136. at idle the oe alt should deliver 60amps. still kinda low. in my case it was worse. the 120 oe alt for a 96 put out 45amp at idle. the diesel 200 amp alt generates 90amp at idle. its a direct bolt in swap. 2 types. 2 different harnesses available. my arbor excite wires lead to a ground modual. it mounts in four small bolt positions on back of the alt. the newer type have a simple plug and wire harness for the exciter. the bid D also spins backwards. NO WORRIES.

 

Yeah, I saw the pic of that belt routing, that was pretty creative. The thing that always made me mad with my truck is with all of the mods I performed I was never able to crack into the 15s. I just wanted it to pull a 15.99, just so i could say that it was sub 16, but i could never get below a 16.2.

 

9 inches shorter on the belt! even i cant believe it.

 

what no SCT? you ot to get the a/f ratios right. bump up the ignition advance. the stock pcm just cant do it!

 

I can't believe a belt that short actually fit, that is really cool. I have the Hypertech PPIII, they didn't have the SCT when I bought my programmer back in '03. I considered a Jet Stage II back then but read the bad reviews and stayed away from it. I'll dig up my last time slip and post it on here on Friday, it is from '06.

 

Interesting on the idle voltage of 13.89 volts... A few weeks ago I installed a 120/90 amp alternator like that pictured in post #24 accept it's driven by a pair of v-belts and idles at the same voltage with the stock regulator and increases to 14.10 volts with the headlights on.
The crank pulley is 7" and the alternator is 2.60" making the alternator spin 2.69 times the engine rpm. I have MSD ignition and Commander 950 TBI.

 

i'm considering an iggy box. my idle is rich on the narrow band o2s. the dyno tuner swares the mix is correct. just think this new engine could be a bit smoother down low. maybe a jacobs, mallery, or match the coil i got going and use a msd. i think the quality control is droping off at msd though.
ya! any running voltage at idle less than 13.5 with ALL the accesories on is too low. B-300 thats a 200/90 amp alt from a diesel. has twice the windings inside than a standard.

 

take a look at Davis unified ign DUI ,, performance distributors also called livewires
have their set up on the mustang for years with issues
and putting on ram next tune

 

local shop that rebuilds alt?