Need some 4.6 two cam INFO

[jk5.0]

Ok I need some guidance. I am looking for another mustang and I came across a few clean 96 to 98 GTs in my price range. Form what I have seen on other mustang boards they say that on these years the heads are the week point and should be replaced to see any decent power gains.

So my questions are the heads really that bad? What does it take money and parts wise to see 300 to 350 wheel hp NA? Also is the PI swap worth doing or a waist of $. I love the way a stout 4.6 sounds and would love to have one just don’t want to go broke building one. :cool1:

[Dirtyd0g]

That is a huge debate, with porting and valve changes the NPI heads can produce better torque output than the PI counterparts. Stock for stock the PI heads are better. I like using the stock MarkVIII shortblock on PI heads for a nice budget combination. Just doing a PI engine swap is only worth it if you get the motor cheap, putting PI heads, intake and cams on your NPI block offer a compression gain.
Alan

[cstreu1026]

300 isn't a problem but beyond that you are going to spending some money for sure. The easy thing to do would be to buy an all aluminum engine out of an Explorer. Throw in some cams, long tubes, and all the other bolt ons and you should see 300 pretty easy. You could also put in a Lincoln mak 8 short block with TFS heads with bigger cams and i would think 350 would be obtainable.

[jk5.0]

Thanks for the info guys much appreciated. If I end up with one I will budget for some new heads and cams. Or just look for a 4 cam donor car.

[wolverine8490]

The NPI vs PI heads is a big debate. I personally ran PI cams, PI intake with NPI heads and picked up some great gains. From reading online, you will only pick up between 5-10hp with PI heads mainly due to the raised compression. Most of the gain from the PI swap is picked up in the intake.

I stuck with NPI heads because I knew I was going FI down the road. 1lb of boost is worth way more than the raise in compression from NPI to PI heads.