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Intake is ON... Now just troubleshooting.. Please Help!!!

  • Thread starter Thread starter crunchie12268
  • Start date Start date Aug 16, 2004
C

crunchie12268

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Aug 4, 2004
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Manhattan, KS
Aug 16, 2004
#1
  • Aug 16, 2004
  • #1
Okay today I finally got around to putting on all the stuff in my signature... I ran into some problems but got them fixed... I am having trouble though. It started up and then idles fine and all, but it has less power than it did when I put on all this stuff. I don't know if the fuel pressure is wrong or if the timing needs to be fixed ( I just put it back were it was when I took it off). I don't know if the computer just has to adjust to all the new stuff.. It ran really fine like it was smooth and all, but it didn't have any power.. I felt like I was driving a V6 Mustang. Any ideas.... these are my questions in a nutshell.

1. What should my fuel pressure be set at with the vaccum off and on? (right now it is 40lbs with vaccum on)

2. What should my timing be at?

3. Does it take time for the computer to reset and adjust to all this?

4. I have a small ....tsh..tsh.......tsh kinda sound when I turn up the fuel pressure, but when it comes down it kinda goes away... any ideas on what that could be?

5. Could a vaccum leak cause these problems. (i.e. no power)

I know you guys have done this before.. please help!!! there is some Camaros drving around and they need to be HANDLED!!!
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 16, 2004
#2
  • Aug 16, 2004
  • #2
Vacuum leak could cause the problems - keep checking. Set timing around 14 degrees btdc with spout out. Leave fuel pressure alone - stock - 38-40 psi with vacuum line disconnected and plugged. Given your mods, other than the intake, while the other stuff is nice, none of it is likely to add much HP because your set up is mild enough that you don't really need it yet.
 
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crunchie12268

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Aug 4, 2004
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Aug 16, 2004
#3
  • Aug 16, 2004
  • #3
Would vaccum leak show up on a vaccum gauge?, I have one just curious if I could find it with that
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Aug 16, 2004
#4
  • Aug 16, 2004
  • #4
stock ish motor should have 15-20" of vac at idle.
make sure your vac line to the FPR does not have fuel in it. the puter will adjust the injector pulsewidth if you go a bit over with FP (FYI).

good luck.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 16, 2004
#5
  • Aug 16, 2004
  • #5
As hissin alludes to, if it's a big leak it may show up - problem is that with your mods it's hard to know what to compare it to. With stock cam (right?) and those heads I'd expect something around 17-20" vacuum. So if you're getting 11" at idle, yeah, you got a leak somewhere. If you get 16" at idle - well, it's hard to say.
 
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crunchie12268

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Aug 4, 2004
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Manhattan, KS
Aug 16, 2004
#6
  • Aug 16, 2004
  • #6
good news, I have 19" at idle, and then it jumps higher when I rev it.... Does this mean I don't have a leak, I hooked it up to the vacuum pod were the three hook up on the firewall and it looks like an F, on the passenger side (I don't know if it matters were you hook it up) But I adjusted the timing to 14ish and found that the fuel pressure was at 49lbs with the vacuum off, I brought it down to 40. It ran better, but still not how it should be. Do you think I just need to tune it a little... and do you think the computer needs to adjust?
 
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crunchie12268

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Aug 16, 2004
#7
  • Aug 16, 2004
  • #7
also I have 1.7 rockers on a stock cam... I don't know if that helps anything
 
D

dromeda

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Apr 17, 2004
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Aug 16, 2004
#8
  • Aug 16, 2004
  • #8
If it runs, I'd say drive it around the block a few (30 miles or so) to let the compu adjust to everything...

Since you pretty much have new everything, (heads, intake, etc.) I'd consider getting a chipped burned (unless you're going blown soon then I'd wait for that)
 
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crunchie12268

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Aug 4, 2004
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Manhattan, KS
Aug 16, 2004
#9
  • Aug 16, 2004
  • #9
I forgot that I had MSD and I put my hand on the top to adjust it and BAM! My eyes burned for a little bit and it woke me up.... There is a moral in this.
 
8

88gtvertboy

New Member
Aug 16, 2004
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maple valley wa.
Aug 17, 2004
#10
  • Aug 17, 2004
  • #10
Driveability Problems

Do you have a stock cam and if so I think you might have problems with all of the mods you did. First you have to much air and fuel going in and thats fine but wouldn't you think that you would need to be able to get it all out. By that meaning a larger cam to move more through.... just a thought.
 
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crunchie12268

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Aug 4, 2004
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Aug 17, 2004
#11
  • Aug 17, 2004
  • #11
I have 1.7's on a stock cam, I would think the with that much lift it would be cool, maybe the duration of the stock cam isn't enough. I found an Isky Cam with 1.6's that would be absolutly perfect. It is really nice, but no $$$ right now. That would be an additional 400 some bucks.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 17, 2004
#12
  • Aug 17, 2004
  • #12
Get the fuel pressure down into the 38-40 range (hose off) and then drive it for a while. The computer will take some time to adapt to the new pressure/conditions. See if it doesn't get better with time. If your maf was calibrated for your air inlet set up, with your mods that thing ought to idle and drive like a stocker on steroids.
 
C

crunchie12268

New Member
Aug 4, 2004
599
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Manhattan, KS
Aug 17, 2004
#13
  • Aug 17, 2004
  • #13
I will try it, I can't get out til around 3:00, but I will bring the pressure down a little and bring the timing up a degree... or maybe bring it down... I don't know if backing it off would give me some throttle response... maybe bring it down to 12. Can I PM you if I have a question?
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 17, 2004
#14
  • Aug 17, 2004
  • #14
email me direct at myount@senndelaney.com. I'd change one thing at time. Leave the timing alone - drive it for awhile; then try the timing. More response will come from more timing, not less. Leave it at 14.
 
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