How much BOOST will it make ?

[sixseclx]

I have a vortech ys trim (currently being rebuilt, wiil have it back friday) that I had on a 306 which had performer rpm heads gt-40 intake lunati 014 grind cam. with a 6.87 lower and a 3.33 upper it made 10 psi @6200rpm changing the upper pulley to a 2.95 it made 16 psi @6200rpm
Now I have a 408 9.6.1, comp victor jr heads, trick flow R intake and the cam is a .576 .592 cut on a 114 ls, and I shift this motor @6200rpm also. I am trying to figure out how much boost this motor will make, with the same pulleys. I don't know how much boost i will loose due cubic inches, if any. and I would also like to know how much boost I can run on pump gas. (SAFELY) thanks for any input

[WIKDLX]

boost is just a measure of restriction in a given motor. if your new motor has better flowing heads exhaust and intake it will show less boost because it is being more effificient.

basically, it should be time to pulley it up!!

[brian97cobra]

boost is just a measure of restriction in a given motor. if your new motor has better flowing heads exhaust and intake it will show less boost because it is being more effificient.

basically, it should be time to pulley it up!!

x2


that should also be a bad mo foe also with that blower on a 408.

[Plowboy72]

make enough to lift the heads then back off a little! just kidding, Matt is right. But you should be fine with about 12lbs or less on pump gas.

[sixseclx]

Thanks for the info Matt, maybe with the 2.95 upper pullley and will only make around 12psi so I can leave it on the pump gas and still make good power!