4.6 cam and intake question??

[cobra clone 98]

i have a 98 gt 5 speed with bolt ons like i said before. the question i have which has probably been
talk about before. am thinking about doin a cam and intake swap only how much would i gain out of it??
and what yr would be best for the cam and intake. i have heard that 01 gt was the best yr to look for..

 

[Ferocious]

Are you just putting PI parts or are you going with a better cam/intake combo? If just PI cam/intake, then i think its like 20-30hp.
And 01+ is easier because the cams are romeo cams.

The cams will bolt right in, just make sure for the intake you get a new coolant nipple and tube that runs in the valley cause the npi one doesnt fit.

 

[cobra clone 98]

ok thanks i was wondering if there will be any problems bolting the p.i stuff on..
but yea am just doin the intake and stock cams swap.. i heard that the 98 gt head they messed with alittle bit when it came to
air flow.. dont know how true it is..

 

[BigBore96]

You could run a custom NPI cam and a pi intake and be faster. Just a thought.

 

[cobra clone 98]

how much would i gain with a custom grind cam over stock p.i cam??? and how big of a cam???

 

[97FloridaGT]

More than what the factory PI can can offer. A custom grind will do wonders for you since it will be specific to your car and your mods, not a one size fits all.

 

[BigBore96]

If you keep the NPI heads you can run a much larger cam and dial it in real good and make awesome power without removing the head.

Check out modularheadshop for cams. I posted the link in another topic that is similar to this one just the other day

 

[cobra clone 98]

thats good to know. then why dont other people with the npi heads just do that instead of changing the heads??
am goin to keep my heads. now what i heard before the 98 gt heads are alittle different then the 96 and 97 gt heads.

 

[BigBore96]

thats good to know. then why dont other people with the npi heads just do that instead of changing the heads??
am goin to keep my heads. now what i heard before the 98 gt heads are alittle different then the 96 and 97 gt heads.

The reason is people just don't know about using a bigger NPI specific cam. It's a more recent idea whereas the PI swap is old school.

 

[97FloridaGT]

Thanks for the education on that ideology BigBore, from a mustang/modular newb.

 

[FrankenStang]

i squeezed alot outta my npi heads...and my buddies cougar on npi heads is running lowlow 13's....i did a PI cam swap and intake and did knowtice nice gains that i could feel in evrey rpm band...and the cam swap we did with the heads on by putting tension on the timing chain with the timing cover on even...took us like 43 or 4 hours start to finish...

 

[cobra clone 98]

thats cool to know.. i will just get me a custom cams for my heads then and do the intake swap.. now by doin the custom cams can i use the stock stuff that is already on the heads?? am use to doin the 5.0 in the foxbodys there easy. so the 4.6 is all new to me lol...

 

[BigBore96]

All the rest of the stuff in the heads will work, lash adjusters, followers, springs, etc. As long as you don't go too high on the lift.

Also, this needs to put here as well. I didn't mention it before.

IF GOING THE NPI CUSTOM CAM ROUTE SUCH AS THOSE SOLD BY Modularheadshop.

YOU MUST! REPEAT! MUST!

Degree them and advance the cams properly per Nick from MHS's specs or you will not be benefiting as much as you should and you'll be wasting your time.

 

[96TANGERINEGT]

Dum question here , and don't mean to go off topic, but how much lift do pi cams have over npi cams anyone know ? Or what is the major difference between the 2 . Just wondering

 

[97FloridaGT]

What is the max lift you can run on the stock springs before you run in to floating and binding issues?

 

[BigBore96]

PI cams have more lift and duration than NPI cams. Espcially on the exhaust side where NPI heads need improved flow. Exact specs I forget. But it's considerable. Though there is lots of room for improvement if considering pi cams in npi heads, I wouldn't do it even though it would be better. But it wouldn't be "awesome".


It's like .525 lift before you need bigger springs IIRC.

 

[cobra clone 98]

thanks guys for all the info it helps alot.. am not wanting to go to crazy just cause am goin to run the on3 performance turbo kits later. am just looking right now to help pick the car up so i will have a way better 1/4 mile time. with the other mods done and the programer i want to run it should help the car out alot i hope..