bpt pulleys

[luckycharms]

does the unduerdrive pulley of a bp fit on a bpt..someone tell me taht don't fit

[90prtege]

someone told you wrong then cause its the same block and head only big diff is intake and exhaust

[luckycharms]

thanks...the bloc is the same anyway

[theredrocket]

There are two different types of pulley though. Be sure to use the right one. One has a multi ribbed groove for the AC/PS and a v-belt groove for the alternator/water pump. The other pulley has multi-ribbed grooves for the AC/PS and the alternator/water pump. Both will bolt to the engine though, yes.

[luckycharms]

There are two different types of pulley though. Be sure to use the right one. One has a multi ribbed groove for the AC/PS and a v-belt groove for the alternator/water pump. The other pulley has multi-ribbed grooves for the AC/PS and the alternator/water pump. Both will bolt to the engine though, yes.

that i know, i'm working at a mazda dealer

[Turpro]

Also, don't forget that there's 2 different size cranks. Small nose=22mm and big nose=27mm.

[luckycharms]

but does the bp and the bpt can have the same crank?

[Turpro]

but does the bp and the bpt can have the same crank?

Yes. You have to measure them to see which 1 you have though

[luckycharms]

but why the don't put the same crank on alle bp for exemple..2 crank on the same motor

[deadly_sleeper]

There was a year break, where 90-92 (or something) had the small nose crank, and then 93-94 had the large nose crank. As Chris said, you will need to take the pulley off of your BP and just quickly measure the crank to see if you got a big nose or small nose crank.

[Jho]

http://www.miata.net/garage/crankshaft.html

[me19875]

so wait, if you buy an imported gtx motor you could end up with a short nose crank?

[therieldeal]

yes.

they seem to mostly be long-nose style actually (not to be confused with big nose)... not the original small/short nose.

[me19875]

yes.

they seem to mostly be long-nose style actually (not to be confused with big nose)... not the original small/short nose.

ok, so i now know the long nose and big nose are different, but for realistic power levels is there any difference in reliability? are the long nose ones known to ever break?

[luckycharms]

thanks guys