• Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

I did the copper pipe cap mod.

  • Thread starter Thread starter 99GHOST
  • Start date Start date Apr 12, 2004
  • 1
  • 2
Next
1 of 2 Next Last
9

99GHOST

Member
Nov 15, 2002
105
0
16
Apr 12, 2004
#1
  • Apr 12, 2004
  • #1
This mod works and does help bring the RPM's down quicker. I was pleased and have not had any problems with the AC. For those that don't know....
all you do is get a 1/2 inch copper pipe cap from a hardware store and drill a 1/4 inch hole in it and place it in the tube that goes between the little black box and your intake. Don't worry it will not get in your engine. Some people use a 3/16 hole but that may cause idle problems with the a/c on. Whew this the longest I have ever typed on a thread.


 

gtrackd02

New Member
Aug 2, 2003
290
0
0
st clair shores
Apr 12, 2004
#2
  • Apr 12, 2004
  • #2
Why does the slow rpm drop bug everyone so much?

I might try it just to see, but the way the r's drop now is fine by me...
 

KJ Hoppus

New Member
Mar 18, 2003
1,008
0
0
Elk Grove CA
Apr 12, 2004
#3
  • Apr 12, 2004
  • #3
what if you dont have ac, how big should the hole be?
 
9

99GHOST

Member
Nov 15, 2002
105
0
16
Apr 12, 2004
#4
  • Apr 12, 2004
  • #4
KJ Hoppus said:
what if you dont have ac, how big should the hole be?
Click to expand...
Try 3/16.
 

nickthegenius

Active Member
Dec 23, 2002
1,631
1
38
Elwood, IN
Apr 12, 2004
#5
  • Apr 12, 2004
  • #5
gtrackd02 said:
Why does the slow rpm drop bug everyone so much?

I might try it just to see, but the way the r's drop now is fine by me...
Click to expand...

For me, its because I have never owned another car that hangs like this car. I just find it irritating.
 

jamathi

Founding Member
Aug 19, 2002
87
0
7
Chicago,IL
Apr 13, 2004
#6
  • Apr 13, 2004
  • #6
Hey I want to try this. Can someome post a pic of exactly where to put the cap. Pictures make things easier Or is there a link to a detailed right up on this?
 

cracula69

Founding Member
Aug 11, 2002
425
0
0
Stamford, CT
Apr 13, 2004
#7
  • Apr 13, 2004
  • #7
ttt
 

JonJon

Founding Member
Aug 16, 2002
4,801
1
68
back in Marylands
Apr 13, 2004
#8
  • Apr 13, 2004
  • #8
I need to do this... rpms are hanging a lot.
I'm gonna try tmw if I can find a drill.
 

JonJon

Founding Member
Aug 16, 2002
4,801
1
68
back in Marylands
Apr 13, 2004
#9
  • Apr 13, 2004
  • #9
Here's an older thread that talks about it, along with a link to a Corral thread.
http://forums.stangnet.com/showthread.php?t=407093
 

gnat

New Member
Feb 25, 2004
144
0
0
Apr 13, 2004
#10
  • Apr 13, 2004
  • #10
I may have to try this... the corral link from the link above is a detailed pain in the arse way it seems. I won't be doin that one. I would love to see pics of this before i jump in and screw mine up!
 

GoldnGT

Founding Member
Aug 21, 2002
427
0
0
Birmingham, AL
Apr 13, 2004
#11
  • Apr 13, 2004
  • #11
why can't people post pics of this.. gah... out of the year this idea has been out there noone has been able to post one pic of it?

Mike
 

JonJon

Founding Member
Aug 16, 2002
4,801
1
68
back in Marylands
Apr 13, 2004
#12
  • Apr 13, 2004
  • #12
edit: my friend took his dremel kit home so no copper mod for me until I can find a drill. my RPMs hang since I installed a tb pipe. before she idled down good.
 

dsg_gt2004

New Member
Mar 23, 2004
423
0
0
Georgetown,SC
Apr 13, 2004
#13
  • Apr 13, 2004
  • #13
thanks
 

steedastangt

Founding Member
Aug 29, 2001
141
0
0
newbraunfels,tx
Apr 13, 2004
#14
  • Apr 13, 2004
  • #14
i did something like but much different. Used-oil cap breather, two tire valves(entire rubber piece). replaced my oil cap with breather, removed the tube that goes from the passenger side cam cover to the intake. slipped the tire valves into its place to fill the holes.
 

Stangt00

New Member
Oct 6, 2003
50
0
0
Apr 15, 2004
#15
  • Apr 15, 2004
  • #15
Subscribing.
 
S

slow87GT

Founding Member
Jun 5, 2000
162
0
0
Tonawanda NY
Apr 16, 2004
#16
  • Apr 16, 2004
  • #16
after this thread I did something simialar, I noticed a pcv fit perfect so I cut it in half, gutted it, used the lower have of the casing, fits perfect

BUT I haven't seen any improvement, the only difference is idle goes up to 1100 when compressor comes on, w/hvac off it idles perfect at 750(sounds like 450 lol)

revs down the same for me, NO BENEFIT
 
9

99GHOST

Member
Nov 15, 2002
105
0
16
Apr 16, 2004
#17
  • Apr 16, 2004
  • #17
slow87GT said:
after this thread I did something simialar, I noticed a pcv fit perfect so I cut it in half, gutted it, used the lower have of the casing, fits perfect

BUT I haven't seen any improvement, the only difference is idle goes up to 1100 when compressor comes on, w/hvac off it idles perfect at 750(sounds like 450 lol)

revs down the same for me, NO BENEFIT
Click to expand...
What size is the hole in the pcv?
 

JonJon

Founding Member
Aug 16, 2002
4,801
1
68
back in Marylands
Apr 16, 2004
#18
  • Apr 16, 2004
  • #18
slow87GT said:
after this thread I did something simialar, I noticed a pcv fit perfect so I cut it in half, gutted it, used the lower have of the casing, fits perfect

BUT I haven't seen any improvement, the only difference is idle goes up to 1100 when compressor comes on, w/hvac off it idles perfect at 750(sounds like 450 lol)

revs down the same for me, NO BENEFIT
Click to expand...
maybe u need a copper piece
still looking for a drill to do this mod
 
2

281Ponies

New Member
Nov 14, 2003
190
0
0
Apr 16, 2004
#19
  • Apr 16, 2004
  • #19
I tried this lastnight, .26cent 1/2" copper cap drilled 1/4" hole and didn't get any better or worse results. I don't have a hanging idle problem, I was after the quicker rpm drop but nothing. I tried running the car after putting the cap in and tried again after disconnecting the battery, the car ran both ways exactly as before attempting this.
I assume I placed the cap in the correct place, short black hose between the black box and the TB, this is the correct place right?

-Cale
 

Blev

New Member
Aug 17, 2003
1,295
1
0
So. Cal. V-Town
Apr 16, 2004
#20
  • Apr 16, 2004
  • #20
The red circle is the TPS and the blue circle shows the IAC...

klry79 suggests putting the cap in BACKWARDS.

Start with a 3/16 of an inch hole and go the next bit size up if you need to. We all may have the same parts on our cars STOCK, but as we put mods on I strongly believe that it alters other things. So some people may need the 3/16 while others may need the 1/4 inch. Just my .02, take from it what you will. I also posted about this a few weeks back. I HATE the slow dropping RPM's
 
  • 1
  • 2
Next
1 of 2 Next Last
You must log in or register to reply here.

Similar threads

M
Progress Thread mnky99 2001 V6 evap core, ac compressor, heater core replacement
  • mnky99
  • Sep 5, 2025
  • 1996 - 2004 SN95 Mustang -General/Talk-
Replies
1
Views
619
1996 - 2004 SN95 Mustang -General/Talk- Sep 5, 2025
mnky99
M
Intended Headers and Trans, questions about fitment
  • from6to8
  • Aug 6, 2024
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2
Replies
22
Views
2K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Feb 6, 2025
from6to8
H
New kid on the block
  • HydraX
  • Mar 22, 2025
  • The Welcome Wagon
Replies
17
Views
876
The Welcome Wagon Mar 22, 2025
HydraX
H
A
Fox Planning on building my foxbody and was wondering if I can get any tips or anything to watch out for!
  • Angelq1028
  • Oct 31, 2024
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 2 3 4
Replies
76
Views
5K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Jun 29, 2025
Robman8028
R
Place to Avoid: Jamison Auto Group in Gulfport, MS
  • D Durden
  • Oct 20, 2025
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • 2 3
Replies
46
Views
3K
1965 - 1973 Classic Mustangs -General/Talk- Jul 16, 2026
Noobz347
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?