Screw 2Vs heads, they absolutly suck, and kill the power potential....Man you guys are supposed to me smart and actually know things about engines, yet most of you take lightly how much heads do for power and potential, and think that crappy flowing heads will give you all the power you want if you put a supercharger on it....well you guys can just keep on believing that.OK enough talk, here are the numbers. BTW not flaming.
Intake valve lift--------99Cobra stock--------STG III
.500 243 292
Intake valve lift--------99GT stock-----------STGIII*
.500 179 204
.600 181 212
*with stock sized valves(1.76 intake 1.41 exhaust)...with 1.83 intake and 1.41 inch exhaust FRPP valves the STG III heads still could only flow 224CFM on the intake at .600 inches of lift
As you see, the stage three 2V heads with bigger valves were still being out flowed by
STOCK 4V head by 19 CFM.If you compare both at the 4V heads .500 inches of lift (instead of the 2V being at a higher .600 over the 4Vs .500) it outflows them by 25 CFM.And you could imagine how much those 2V heads would cost...thats why I am also going the 4V swap route....in short 2V heads are a joke and they SERIOUSLY limit our power, I can think of only one reason why some one would do a high powered build up of 2V head motor...and thats for the bragging rights.
CLIFF (sp LOL) NOTES... 2V heads suck, and even with a bunch of work cant match the flow of stock 4V heads.
Well thats my .02 take it or leave it....also hope that helped anyone who had any Qs about that sort of thing, or was having a hard time deciding between 2V and 4V heads.BTW all info was from 5.0 MUSTANG AND SUPER FORDS.They had the flow bench not me LOL.