I purchased a posi ported Eaton Cobra that has not been driven/tuned since getting the posi port put on it. Anyways, I measured the lower pulley and it turned out to be a 8lb metco lower! Upper pulley is a 2.93. I've already established through research that this combo will overspin the eaton quite a bit, but now I am debating on what will be my best option in order to correct it before sending the car off for a tune.
The alt pulley is a 3.7".. so keep this in mind. Whichever route I go I want to not have to change the alternator pulley if at all possible.
Should I replace the upper pulley with something like a 3.1 or even stock size?
Or Should I just replace the crank pulley ring with a 6lb and retain the 2.93 upper and 3.7" alternator pulley? I saw one for sale on here for dirt cheap but not sure if the 6lb lower will work well with upper pulley and alternator pulley.
My goal is to make it to the 500whp mark (Car has a KB BAP, 60# injectors, sct ba2600, bbk 65mm)
The alt pulley is a 3.7".. so keep this in mind. Whichever route I go I want to not have to change the alternator pulley if at all possible.
Should I replace the upper pulley with something like a 3.1 or even stock size?
Or Should I just replace the crank pulley ring with a 6lb and retain the 2.93 upper and 3.7" alternator pulley? I saw one for sale on here for dirt cheap but not sure if the 6lb lower will work well with upper pulley and alternator pulley.
My goal is to make it to the 500whp mark (Car has a KB BAP, 60# injectors, sct ba2600, bbk 65mm)
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