Question about cams

98bluevert

New Member

Jan 22, 2006

130

0

0

Mattoon, IL

Jun 21, 2006

#1

• Jun 21, 2006

• #1

how high of a lift cam will a stock nPI motor handle without PTV issues. also would i have to get new springs.

 

'13_ImpactBlue_GT

Angry Little Elf

Mar 30, 2005

872

2

98

Where the men are men and the sheep are nervous

Jun 21, 2006

#2

• Jun 21, 2006

• #2

I dont know about the NPI motor but the VT Stage 1s for my GT dont require new valve springs, just a tune.

 

98bluevert

New Member

Jan 22, 2006

130

0

0

Mattoon, IL

Jun 21, 2006

#3

• Jun 21, 2006

• #3

i know if i go with stage 2's i need springs but since my stock lift is like .473 i didn't know if i could use something like .550

 

jasonh_86

I

May 20, 2005

1,156

2

48

Arkansas

Jun 21, 2006

#4

• Jun 21, 2006

• #4

When my VT Stage 2 N/A cams came in, the spec sheet read ".562/.576 lift".. I went with the manley Nextek springs.

But i'm sure the NPI motor could use the VT Stage 2's without ptv issues, since it's a pi/npi cam.

But you can't go wrong with the Stage 1 from VT

 

'13_ImpactBlue_GT

Angry Little Elf

Mar 30, 2005

872

2

98

Where the men are men and the sheep are nervous

Jun 21, 2006

#5

• Jun 21, 2006

• #5

You are quite correct sir, when I first crank her up the sound is pure heaven....blubblublblubblubblubblub, I will have some vid. clips up this weekend :SNSign:

 

98bluevert

New Member

Jan 22, 2006

130

0

0

Mattoon, IL

Jun 21, 2006

#6

• Jun 21, 2006

• #6

ok did a search and finally found this by DropTopPony and TGJ

DropTopPony said:

if you still have stock 98 heads you can't use VT cams or any other PI Aftermarket cams. The stock PI cams are a direct swap and Comp/Crower make NPI Cams.

Click to expand...

TGJ said:

Ummm, the Comp PI cams will work in NPI heads. You will need the Crower Offset retainers and upgraded springs to run some higher lift cams in the NPI heads. You will need these for the higher lift PI Comps. I would say the ideal cam for a mild modded car would be the Comp 262AH( PI ) Cam.

Click to expand...

So if i get aftermarket PI cams like COMP or VT's then will they work with nPI heads with offset retainers? Also if i get the 262ah or stage 1 do the springs have to be upgraded?

Anyone with more info please chime in.

 

X

xmikevankuikenx

New Member

Oct 16, 2005

29

0

1

Jul 4, 2006

#7

• Jul 4, 2006

• #7

Comp cams makes 3 different cams for the npi heads:

XE262H
XE268H
XE274H

 

COramprat

...I can take it. I think.

20+ Year Stangneter

Mar 2, 2003

8,474

1,463

223

Sea of Tranquility

Jul 4, 2006

#8

• Jul 4, 2006

• #8

I installed Comp 262ah's in my NPI 96 with about 120k. Didn't swap the springs and have had no issues with valve float and now pushing 170K. Anything more than the mild cams though I would suggest valve springs. Just a thought though...the HP difference between the 262 or stage 1's and more aggressive cams is not too much...around 5-15HP depending on the set. I can live with my 25HP bunp from the 262's.

 

Cantslowdown

New Member

Jun 20, 2004

502

1

0

Mt.Home AR!

Jul 4, 2006

#9

• Jul 4, 2006

• #9

Dang thats alotta miles with those cams...Says something about 4.6s they are good motors if taken care of..

 

T

TGJ

New Member

Mar 30, 2005

1,049

4

0

Jul 4, 2006

#10

• Jul 4, 2006

• #10

VT Stg II cams will not work in NPI heads with just Crower Offset retainers. To run more than .545 lift cams in NPI heads requires more. .545 lift is the actual lift of Comp's off the shelf PI modular cams, just an FYI. I know they advertise .550, but if you actually check, they turn out to be .545.