fast plan

any real point to spend the money on porting the stock 4.6 DOHC heads? or would i be better off going to an after market dealer....and what would be the whp gains from just doing a head swap/ port/polish larger valves ect...


i plan to get cams and i figured since i have it all torn down anyways why not dig into the heads..but if it's not really worth the money/effort i'll just do what i need to, to add these shm stage three cams.

1997 cobra...nothing to do and alot of money to spend

04BlueGT

All the heads on the aftermarket are just modified factory units. They do core exchanges to feed their supply, so porting yours or buying them ported makes little difference, except price and warranty, maybe. If you know a really good shop to do the porting and the price is right, I don't see why you'd need to buy reworked heads.

As far as results, p&p heads with cams will make a huge difference according to those who have them. You can get custom grinds for you applications from some sites. VTengines.com makes good stuff for GTs, but not sure about 4V motors. Check them out.

Tim37

with a 97 cobra your best up grade would be to get a set of 03/04 4v heads and mach 1 intake slap on there. or instead of the intake go ahead and toss a supercharger on there.

HaV

Hey Tim, I kinda asked this in the SVT forum and got no response.. Do you know if the 03/04 Mach or Cobra heads will bolt right up? Are there any clearance issues or anything in the engine need to be reloacted after that swap? I would kind of like to do this as well sometime this summer.

Tim37

ok im no expert buy any means but about a year ago i found a 97 cobra motor for sale. i did a little reseach before deciding agianst it. the main diffence it the intake there is a valve that shuts off one of the intake runners on a 96-98. the other is how the air flows in the head thats why if you swap heads you need to swap intakes. other than that i don't know of any clearance issuese.

fast plan

so what kind of gains would i see in 6the head swap? as for the supercharger...i have an s-trim sitting in my room next to me just waiting...i'm having the cams overnighted and should be here tomarrow, and i have a DD so it doesn't matter if the car sits awhile...but honestly i was wanting to stick with the stock heads to see what they are capable of...unless the mach 1 heads are worth the money that is.

Tim37

stock heads on a super charged apliction will be fine you would probably see better gains with a set of cams than heads but i still don't like the air control thing i keep forgeting what it is called but basicaly a set of butter fly valves on the second set of intake runners.