well I have been racing fords for 20 years or better my 302 with ported factory 69 windsor heads went 11.70s at 117 on motor .wich tells you there is more there. and went 10.70s at 125 on 150 shot it had a bit more compression than stock 13 to1 but I have run hi 10s on flat tops on 200 shot it is not rocket sceince so the ford guy you who says it cant be done obviously has never met me. I am finishing my mustang II now and it has 68 302 heads and will most definately run 10s and low 12s or hi 11s on the motor if you have ever seen nhra stock class records for non ported head motors is low 11s or maybe even 10s by now. and I forgot to mention I port my own heads and have for years my windsor heads will swallow a pair of non ported trick flow heads.
what do you think people did before all these heads came out.the only thing that will keep it from going 10s is head gasket failure.and if the heads that they have ar not big enough well I just happen to have a pair sittin here that have been 10s that I will gladly donate. they said they had a pair of ported windsor heads. they are almost the same as gt 40 heads before porting, and yes I doubt it will go 9s with 302 but with a 351 windsor it definatly can be done.dont be mad just build something badder ( if you can)