If I'm not mistaken, turbo can be 3 bolt up to 75 mm, no 4 bolt or v band.
other then that 109 block, mim wieght 3450 iron heads 3550 alumium, any tire you want,
anyone racing the class needs to fill up with all other racers and put 10 gallons 93 in from the same source
And Julio amd Clint are right all this class needs is RACERS!!!!
this class has always use the KISS method Keep It Super Simple!!!
JD