i got my heads back from livernois. i paid extra to have before and after flow done. i had livernois bowl blend and do a race valvejob while adding stronger springs for long duration 8000rpm duty. gains are marginal, but this is all done without increasing port size, so the velocity should still be superior to similar flowing ported gt heads. it remains to be seen if that means anything in real life though.
it was at least interesting to finally get some real flow numbers for the boss heads, as i have never seen them posted before. the printed 4-6% better than gt heads on the intake is closer to 4% and the 10% claim is just that...or ford was factoring the cams into the equation, because they are nearly identical to JPC's stock gt head flow data.
ok, here are the numbers:
LIFT GT-int BOSS-int LIV-int GT-exh BOSS-exh LIV-exh
.100 99.0 100.3 98.0 72.2 82.4 85.2
.200 180.2 187.0 187.1 147.8 138.2 141.7
.300 243.5 243.0 246.7 180.0 176.1 179.7
.400 280.0 280.6 291.9 189.7 192.2 194.8
.500 289.4 304.6 315.7 201.4 199.7 203.4
.600 298.4 311.9 322.3 202.1 202.4 206.1
there you have it. use it how you like. i am not sure, at this point, if it was worth the money, but it was a gamble and someone had to try it out.
where i feel it will do well is with better cams. i decided on the relatively mild CJ cams to go with these heads, as i want to get close to the 500rwhp without sacrificing around town torque too much. with fords engineering in the boss heads left in tact and just eliminating some small restrictions and using the CJ cams that have 150k mile durability standards and use the same intake duration with 1mm more lift, i feel its the best shot for a limited compromise engine. hell, just looking at the 12mm intake flow on the stock boss heads of around 299cfm and then the 13mm intake flow on the worked head of around 317cfm is really good news for power production!
its also interesting to note that adding lift past the comp cams 12.5mm is nearly useless. flow on gt, boss and even the worked boss heads flat lines from .492 (12.5mm) to .551 (14mm) with only around a 1cfm increase. its all about duration there, and the CJ cams offer more than i believe any others do.
it was at least interesting to finally get some real flow numbers for the boss heads, as i have never seen them posted before. the printed 4-6% better than gt heads on the intake is closer to 4% and the 10% claim is just that...or ford was factoring the cams into the equation, because they are nearly identical to JPC's stock gt head flow data.
ok, here are the numbers:
LIFT GT-int BOSS-int LIV-int GT-exh BOSS-exh LIV-exh
.100 99.0 100.3 98.0 72.2 82.4 85.2
.200 180.2 187.0 187.1 147.8 138.2 141.7
.300 243.5 243.0 246.7 180.0 176.1 179.7
.400 280.0 280.6 291.9 189.7 192.2 194.8
.500 289.4 304.6 315.7 201.4 199.7 203.4
.600 298.4 311.9 322.3 202.1 202.4 206.1
there you have it. use it how you like. i am not sure, at this point, if it was worth the money, but it was a gamble and someone had to try it out.
where i feel it will do well is with better cams. i decided on the relatively mild CJ cams to go with these heads, as i want to get close to the 500rwhp without sacrificing around town torque too much. with fords engineering in the boss heads left in tact and just eliminating some small restrictions and using the CJ cams that have 150k mile durability standards and use the same intake duration with 1mm more lift, i feel its the best shot for a limited compromise engine. hell, just looking at the 12mm intake flow on the stock boss heads of around 299cfm and then the 13mm intake flow on the worked head of around 317cfm is really good news for power production!
its also interesting to note that adding lift past the comp cams 12.5mm is nearly useless. flow on gt, boss and even the worked boss heads flat lines from .492 (12.5mm) to .551 (14mm) with only around a 1cfm increase. its all about duration there, and the CJ cams offer more than i believe any others do.
