yet another cam ?

fast97gt

Active Member
Jan 2, 2007
1,082
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north carolina
im having a hard time tryin to figure out what to use. ive been looking at the comp cams xe262-14, xe268-14, and the xe274-14. ive got a stock npi 4.6, before you guys start bustin my chops, i want the choppier idle, but not to agressive, and still has to be streetable, and i know ill probably have minimal gains in hp and torque without using pi intake and heads. so please help me out and point me in the right direction, and all suggestions are accepted. oh and im not going forced induction or nitrous. thanks everyone

p.s. its a daily driver and what are the stock cam specs for these npi engines.
 
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Dragstr05

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Dec 21, 2004
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Dont know that I can point you in the perfect direction, but I offer you this...

With NPI heads and intake, an agressive cam wont do you much good as its going to be overkill for that combo. The NPI heads and intake just arent going be able to take advantage of all the extra duration. IMO, ATLEAST do the PI intake. Shouldnt cost you no more than $200 or so, and most people sell their stock PI heads for pretty cheap so they are easy to come by.

I would wait till you can do the heads & intake to do the cams, otherwise I dont think you will be entirely satisfied with your investment, and when you finally swap heads, you'll have to take it all apart again anyway.

Just my .02.
 

fast97gt

Active Member
Jan 2, 2007
1,082
2
49
north carolina
Dont know that I can point you in the perfect direction, but I offer you this...

With NPI heads and intake, an agressive cam wont do you much good as its going to be overkill for that combo. The NPI heads and intake just arent going be able to take advantage of all the extra duration. IMO, ATLEAST do the PI intake. Shouldnt cost you no more than $200 or so, and most people sell their stock PI heads for pretty cheap so they are easy to come by.

I would wait till you can do the heads & intake to do the cams, otherwise I dont think you will be entirely satisfied with your investment, and when you finally swap heads, you'll have to take it all apart again anyway.

Just my .02.
yea thats what i was thinking but my bride to be was wanting to buy me something, and shes been wanting to get me them for a long time. however i had a 91 firebird formula before i bought my mustang, and i spent almost a month learnig cam specs, and what they meant. i do know the more duration you want the more compression youll need. i think the 4.6 has like 9.5:1, right? if so the 268 would suit me more, correct? the cam i went with for my formula i had to a lot less duration cause the cam i wanted had less lobe sep. that the speed dens. system would allow. and i will be doin an intake swap in month or so.
 

CobraRed_96_GT

Active Member
May 20, 2006
1,421
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UCSD/La Jolla
I'd go with a 268H cuz it's an NPI cam and it has a .50 lift which suits your car. Anything more "choppy" you'll need valve springs and heads would be almost a must. Get the PI intake either way - you need it for the high rpms where those cams will benefit you
 

Tim2002GT

Founding Member
Apr 10, 2002
635
4
29
Tulsa, Oklahoma
I'd go with a 268H cuz it's an NPI cam and it has a .50 lift which suits your car. Anything more "choppy" you'll need valve springs and heads would be almost a must. Get the PI intake either way - you need it for the high rpms where those cams will benefit you

Excellent advice right there!
 

Skidzz

Tinkerbell
Apr 11, 2005
328
1
19
Salt Lake City, UT
NPI heads are a dime a dozen. You could just buy 2nd set of them and have them ported. If I could do my setup again, that's what I would've done differently: Ported NPI head, aftermarket cams, and a PI intake with the adaptor plates. If I did that, I'd still be able to run 87 octane and slap a blower on it. Oh, I probably would have paid less, also.
 

CobraRed_96_GT

Active Member
May 20, 2006
1,421
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UCSD/La Jolla
does anyone know the what the stock cam specs are for these npi engines. evidently im not looking in the right place
Advertised Duration @ Lobe: 233*/242*

Advertised Duration @ Valve: 242*/254*

Duration @ .050" @ Lobe: 186*/191*

Duration @ .050" @ Valve: 202*/207*

Lobe Lift: .256"/.259"

Gross Lift: .461"/.466"

PI Cams - 1999-2004

Crower Cams recommend to advance cams 2* and factory cam gears can be off +/- 5*.

Advertised Duration @ Lobe: 233*/239*

Advertised Duration @ Valve: 242*/252*

Duration @ .050" @ Lobe: 184*/191*

Duration @ .050" @ Valve: 200*/209*

Lobe Lift: .280"/.295"

Gross Lift: .504"/.531"

Centerline: 112*/116*

Intake Opening @ BTDC is -11*
Exhaust Opening @ BBDC is 41*
Intake Closing @ ABDC is is 33*
Exhaust Closing @ ATDC is -11*
 

98GTfromGA

Founding Member
Mar 17, 2002
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www.eccentrix.com
I have the 3.60" pulley, it makes about 8psi at 5500 rpm and 9.5psi at 6200.
To run with higher compression I had my tuner pull a lot of timing out. Its got like 12 degrees where normally a blown car may be 14-18 depending on setup.
 

CobraRed_96_GT

Active Member
May 20, 2006
1,421
2
39
UCSD/La Jolla
I have the 3.60" pulley, it makes about 8psi at 5500 rpm and 9.5psi at 6200.
To run with higher compression I had my tuner pull a lot of timing out. Its got like 12 degrees where normally a blown car may be 14-18 depending on setup.
8 and 9.5 isn't bad at all, and 396rwhp at 12 degrees timing is great. Been searching for people who run boost on a pi swap, there's one guy on turboforums' modular section that's running a garret 60mm but he's hasn't responded telling me what kind of boost and numbers he's got. So i'm glad you responded:nice:

kinda pre-planning a single 62-70mm t4 .86a/f project for down the road.
 

fast97gt

Active Member
Jan 2, 2007
1,082
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49
north carolina
8 and 9.5 isn't bad at all, and 396rwhp at 12 degrees timing is great. Been searching for people who run boost on a pi swap, there's one guy on turboforums' modular section that's running a garret 60mm but he's hasn't responded telling me what kind of boost and numbers he's got. So i'm glad you responded:nice:

kinda pre-planning a single 62-70mm t4 .86a/f project for down the road.
:mad: well dang, didnt know that my thread was suppost to start a chat room, START YOU OWN THREAD, i asked for help and thanks for those who replied but this about my cam question, and ME not you blower combos. so go start your own thread:mad:
 

CobraRed_96_GT

Active Member
May 20, 2006
1,421
2
39
UCSD/La Jolla
:mad: well dang, didnt know that my thread was suppost to start a chat room, START YOU OWN THREAD, i asked for help and thanks for those who replied but this about my cam question, and ME not you blower combos. so go start your own thread:mad:
im not going to start a thread to ask one member who's rarely on about his combo. Yes i could have gone to pm but i wanted to give him props openly. It's not as if i haven't provided you with info on each question you've had. And you haven't even been in the discussion since i gave you the pi cam specs. So cool down spraky
 

fast97gt

Active Member
Jan 2, 2007
1,082
2
49
north carolina
im not going to start a thread to ask one member who's rarely on about his combo. Yes i could have gone to pm but i wanted to give him props openly. It's not as if i haven't provided you with info on each question you've had. And you haven't even been in the discussion since i gave you the pi cam specs. So cool down spraky
heck you didnt even give me the info i asked for. i asked for NPI not PI cam specs, so before you come to me with this cool down sparky ****, go grt bent alright. oh and if theres anyone who knows the specks for NPI let me know thanks.
 

Killa

Active Member
Jul 9, 2007
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heck you didnt even give me the info i asked for. i asked for NPI not PI cam specs, so before you come to me with this cool down sparky ****, go grt bent alright. oh and if theres anyone who knows the specks for NPI let me know thanks.
This kid have problem. Chill bro........ some time **** happent just let it go, in my opinion is since your intake will crack soon or later, go ahead and do pi intake swap, that is the first thing I did to my 98 gt. and go ahead and do all the maintain of the car before doing mod to it, hell I love to swap PI engine in near future.
 

Tim2002GT

Founding Member
Apr 10, 2002
635
4
29
Tulsa, Oklahoma
heck you didnt even give me the info i asked for. i asked for NPI not PI cam specs, so before you come to me with this cool down sparky ****, go grt bent alright. oh and if theres anyone who knows the specks for NPI let me know thanks.

Better look again! The NPI specs are the first specs listed.