Need a little help with how much boost/which pulleys(k24a1)
Hey guys,
I have been trying to read up on pulley sizes because I am trying to get the correct amount of boost on the first try, I can not afford to pay the tuner to swap pulleys while im trying to get it tuned and def cant go back again later for a complete new tune.
My setup is:
K24a1 vtec frank
SRI
JRRH
type s mid pipe
stock muffler
JRSC race kit (planning to mod auto tensioner)
I am trying to get around 8 PSI and I have been confused by this chart in the FAQ:
Quote:
I'm running a K24 or K20a2 engine swap. What supercharger pulley size am I supposed to run?
Here's a little table that I will add onto later when I check my math a bit. But essentially the 5.8" crank pulley is a K20a2 crank pulley and the 6.3" crank pulley is from a K24. So use the table below to get an idea of how fast your crank pulley spins your supercharger and how many pounds of boost your setup will be seeing.
5.8" crank pulley & 3.8" supercharger pulley = 13,000 rpm (or around 4.8psi)
5.8" crank pulley & 3.6" supercharger pulley = 13,700 rpm (or around 6.1psi)
5.8" crank pulley & 3.3" supercharger pulley = 14,900 rpm (or around 8.5psi)
6.3" crank pulley & 3.8" supercharger pulley = 14,100 rpm (or around 6.9psi)
6.3" crank pulley & 3.6" supercharger pulley = 14,900 rpm (or around 8.5psi)
6.3" crank pulley & 3.3" supercharger pulley = 16,300 rpm (or around 11.1psi)
*Please note that the K20z1/K20a crank pulleys are smaller than even the K20a2 crank pulleys.
The chart is confusing as I have read not to use smaller than a 3.8'' pulley (which they dont make anymore i think)
I went ahead and measured my crank pulley last night and ,without taking it off, it measured over 6 inches so I am assuming that I used the CRV pulley that went with the block ( I had no idea they were different at the time so i paid no attention to it). my idler was over 3''.
In another post I read that with the 6.3 cp, 3 in idler, and 3.8 in sp, he was getting 11 psi. this makes me think the 4'' pulley should be fine for 8 psi?
Also I can not find arp rod bolts for the k24, I read that it was a good idea to replace these, does anyone know where to locate these at arp?
Thanks for your input in advance.
