Cylinder heads & CAMs

[GGA]

I have a 4.6 V8 GT 1997.

This is what I have so far: K&N cold air kit, SLP long tube headers, SLP X pipe and cats, Flowmaster Catback, BBK fuel pressure regulator & 70 mm throttle body.

In a few months time (once the missus is talking to me again ) I want to go for modified cylinder heads and cams.

I have modified a number of heads previously back in the UK a few years ago so I would like to do this job myself. My plan is to pick up a pair of stock heads form a breakers and spend time polishing and porting them. Once done I would also like to machine them to get the compression up a bit. I then want to add new cams - not wild but uprated. I have a few questions:

Is my plan ok, it is based mainly around keeping costs down and ensuring the car is still a good daily driver?
how much can I safely skim off the heads to up the compression, bearing in mind higher lift cams going in?
Any reccomendations for the cams?
Can I install Rhodes lifters? These allow you to go for really wild cams but will also let the car run as a smooth daily driver and retain a good tickover. These hydraulic lifters work in a similar way as the Honda VTEC does.

One final question: My car currently seems to run flat above 4500 - 5000 rpm, as if it was being starved of fuel - this was the reason for the fuel pressure regulator upgrade. This is now noticealbe since I installed the LT headers X pipes and new CAT's.

Should I take this to the dyno to get it remapped? Has anyone else experienced this problem? I would guess a visit to the dyno would definatley be in order after head and cam upgrades so I may wait until then.

Thanks in advance

 

[nyuk98gt]

GGA:

Porting the 2V heads is a little tricky. For the price, you are better off with ported heads from Fox Lake or VT Engines (imo). If you install PI heads, you do not want to mill them as the compression will be up anyway.

Cam choices: VT or Comp Cams or Hi-Tech. Again, just my opinion.

Don't know anything about Rhoades lifters. There are only hydraulic lash adjusters and cam followers in the 2V engines. Stockers are perfectly fine unless you intend to run >7500 rpm and spend most of your driving time at the track.

The power band flattens because the non-PI (NPI) intake is a huge restriction. You can install a PI (performance improved, in Ford-speak) intake and you will get a major improvement.

You can buy a headswap kit (heads, intake, gaskets, bolts, etc.) for about $1400. Add another $600 to $800 for a decent P&P job. Job can be done with the engine in the car. Another pair of hands will make it go smoothly. Planning and being organized is vital, of course.

Save your trip to the dyno until you have your new heads, cams, and intake.

Remember to take the missus out often during periods of modding purchases, parts deliveries, and installation. If she ain't with you on your modding adventure, it's going to be hell.

Lastly, search for "PI swap", "PI headswap", "PI intake swap", "cam swap", etc. and you will find hundreds of useful and informative threads. You can also check out Corral and ************ for additional info.

Good luck.

Chris

 

[GGA]

Thankyou Chris, good advice about the Long Haired General

 

[Torinalth]

i'm with the above on this one. since you have a 97, you would benefit greatly by getting a set of PI heads, and a PI intake (pi intake is cheap and you can probably get a nice set of PI heads off someone that has replaced theirs with purchased PNP heads)

while the porting job is fairly involved (working the short turn is difficult from what i understand). this will also keep the costs down allowing you to get a set of stage 1 cams to go in your heads.

he is also correct in the milling process. you can mil about 0.001 off the heads before you start running into problems, however the combustion chamber on the PI heads are smaller then that of your heads, so by just replacing your stock heads with the PI heads you will effectivly change your CR to somewhere between 9.8-10.2:1, but that can also change depending on what cams you get.

i think its a good project. i have shaky hands so porting is not in my vocab... but i can tear into an engine (doesnt require a delicate touch). have some fun with it. and while you are at it, why not replace the valves and valve springs with some better ones. just a thought.

Torinalth

 

[GGA]

When you guys mention the intake restriction, I already have a 70mm TB and a K&N cold air kit.

I will look at the rest of the intake components then - Manifold, MAF, Plenum.

I am new to this forum, great information, thanx for your help

Cheers Gordon

 

[Torinalth]

well, the intake restriction is mainly the upper and lower manifold... its different and less efficient then the PI setup that comes on the 99+ mustangs. the 70mm and CAI from KN will be fine for the rest of the track... but when doing the heads, get the PI heads, lower intake, a good plenum (i recommend dragon) and enjoy the power.

Torinalth