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Non-PI Heads Ported and Polished?

  • Thread starter Thread starter mustangman9812
  • Start date Start date Nov 10, 2005

mustangman9812

10 Year Member
Jan 14, 2004
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Mars Hill, NC
Nov 10, 2005
#1
  • Nov 10, 2005
  • #1
I wanta know if this set-up for show me any gains and if any of you would do this?

There is A very good engine builder in my county and I am thinking about getting my NON-PI heads ported and Polished (I know I wont see as much gain as if i got PI heads ported but i read somewhere where NON-PI heads ported was as good or even a little better than stock PI-Heads). Also getting my plenum ported too. Then pick up 70mm Throttle body, Crower Stage II NPI N/A Cams, Comp Cams Valve Springs, VT Cam Gear Kit, SCT Tuner, Granatelli Mass-Air Flow, and 24lb Injectors. I will still be spraying on this set-up. If I do go with this what other parts would you use or will i need to make this happen? I will be getting the money soon to do this.
 

mustangman9812

10 Year Member
Jan 14, 2004
661
6
49
Mars Hill, NC
Nov 10, 2005
#2
  • Nov 10, 2005
  • #2
O yeh I will need a Stall Converter.
 

CanadaStang

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#3
  • Nov 10, 2005
  • #3
That should help alot. One thing to keep in mind, if you do all those mods at once and the car doesn't run right after, it's going to be tough to track down the problem.
 

DropTopPony

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Nov 10, 2005
#4
  • Nov 10, 2005
  • #4
Heres a real good head porter not too far from you. www.steenracing.com worth the trip. And P&P NPI heads can flow just as good as P&P PI heads.
 

tomustang

Psychotic Member
Founding Member
Jun 8, 2000
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Nov 10, 2005
#5
  • Nov 10, 2005
  • #5
If you're gonna be spraying you might aswell get the 75mm TB
 

mustangman9812

10 Year Member
Jan 14, 2004
661
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Mars Hill, NC
Nov 11, 2005
#6
  • Nov 11, 2005
  • #6
thanxs guys. I was also wondering how good are crower cams?? I have heard good things about them but want really good info. Also how much of a power increase would I see possibly? And Again thanxs for all your help! :SNSign:
 

mrvax

Stay thirsty my friends
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Nov 11, 2005
#7
  • Nov 11, 2005
  • #7
droptopponynj said:
. And P&P NPI heads can flow just as good as P&P PI heads.
Click to expand...

I've heard this claim but never saw data to back that up. I have seen people get P&P NON PI heads to flow almost as good as stock PI heads. If Steen Racing says it can be done, then I'd believe it.
 

BooWFO

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May 10, 2005
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Nov 11, 2005
#8
  • Nov 11, 2005
  • #8
the crower's well VT sells them on their site so I'd say they're pretty good.
I'd think maybe 40-60 rwhp but I always guesstemate low.
 

DropTopPony

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#9
  • Nov 11, 2005
  • #9
mrvax said:
I've heard this claim but never saw data to back that up. I have seen people get P&P NON PI heads to flow almost as good as stock PI heads. If Steen Racing says it can be done, then I'd believe it.
Click to expand...

renegade racing P&P NPI are supposed to flow equal or more then MPH 2.5 PI heads. I have not seen them in person yet. The best place to search for this kind of info is on the Tbird and Cougar forums. Those guys get some damn respectable #'s with NPI heads. I'd like to take my old NPI stuff and see what could be done with it...but thats another day/another project
 
O

o0akoni0o

New Member
Oct 26, 2004
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Fremont, CA
Nov 11, 2005
#10
  • Nov 11, 2005
  • #10
droptopponynj said:
renegade racing P&P NPI are supposed to flow equal or more then MPH 2.5 PI heads. I have not seen them in person yet. The best place to search for this kind of info is on the Tbird and Cougar forums. Those guys get some damn respectable #'s with NPI heads. I'd like to take my old NPI stuff and see what could be done with it...but thats another day/another project
Click to expand...
its funny how those guys pick up the npi heads nobody ones for real cheap and spruce them up to a point where we all look like idiots spending how much we do on our cars, lol.
 
T

TGJ

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Mar 30, 2005
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Nov 11, 2005
#11
  • Nov 11, 2005
  • #11
Renegade Racing Ported NPI's flow almost as well as MPH 2.5 heads. Renegade Racing is building my 5.0L Big-Bore for my TBird. I will have answers regarding your Crower Cam question once my setup is running.
 

Gearbanger 101

Straight Outta Locash
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Aug 10, 2002
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Nov 12, 2005
#12
  • Nov 12, 2005
  • #12
I'm all for ported NPI heads, but for what you're doing, you're probably better off to go with a set of used stock PI heads and add a set of cams to them. Used heads will cost you about the same if not less than a decent port job and the PI swap will bump your compression ratio up to about 10.4:1 which will work ideally with your nitrous application. Doing this will yield much better gains than a set of ported NPI heads and stock compression.
 
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