i havent been around in a long while guys. funds have been low and still are. howerver, i was wondering about the new heads for the 2v. they have been out for a while now. so has anyone tried them or have you seen results on other forum guys cars? i dont mean the sugar coated reviews in the mags, just real life cars that have tried them and have dynoed them. are they what they are all cracked up to be? i know there is 2 different combustion chamber sizes. so its tricky to figure out if they will make power over a regular pi ported head such as i have. would it even be worth the swap for me. i have a blower pushing14 psi and want to go about 16 so i need the stock chamber size so my compression does NOT go up! what do you think?
Yeah they look like they perform very well read the MM&FF article sucks the did do test on charged motor? But still looks like a 35hp-45hp gain over stock heads depending on adder your running?? Still saving for mine
On NA cars with the stock plastic intake they seem to be good for 350RWHP with all the supporting bolt ons and long tubes. No need for a cam bigger than 225 intake duration I learned the hard way unless you get a high RPM intake.
Um why don't you guys buy 4v Navigator heads? Hell i picked up a whole 4v Navigator motor for $700 ....Then you get rid of the beastly Navigator intake for the Sullivan....They Specialize in making intakes for The navigator heads weather on a 4.6 or the 5.4 i believe the Navi heads in stock unported form flow about 325CFM.
Navi heads stock are the worse flowing 4V heads Ford makes. However once ported they outflow all the other 4V heads except the big dawg GT stuff. Stock is another matter altogether as their intake ports/bowls are heavily restricted. If you are not going to have your 4V heads ported then its only the 03+ 4.6 head or the GT head you need to look at IMHO.
Navi heads arent the worst...But then again they are a really big head....Did some reading and they have very limited intake options when used on a 4.6... I guess thats why im using them on a 5.4.
Stock they are the worse but they have more potential than the 4.6 heads. Here is how restricted the stock bowl area is: And here is the same port opened up and roof raised:
yes, i already have the foxlake heads and they were expensive. however, my question now is are the pi ported heads by fox lake just as good as the trickflow heads? the question is do the trickflows really deliver and warrent the change? i know over stock heads of course they will increase performance but how about over good ported pi heads. i picked up 35rwhp from the fox heads and cams so if you only gain the same from the trickflow ones then they are not worth it unless you port them also! then mayb e they are worth the change. so far it seems no one really has any experiance with them. still have to watch the vid someone posted. if i take the chance, i guess there will be a really nice 2 yr. old set of fox lake heads for sale which i have dyno proven hp gains. lol! thanks
From my understanding, the biggest advantage of the TFS heads over a ported PI or NPI head is the bigger intake valve. Trick Flow achieved this by rotating the intake valve in the chamber, but leaving the top of the valve in the same location so not to require a new cam design. This was a huge step forward in the 4.6 2v market as with the stock design, the ability to put a bigger valve in the chamber was nil due to the small bore size.
Bigger valve isn't that much on it, the fact that it has a short side bowl and radius is the biggest part of the gain.
