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Not peaking where it should...

  • Thread starter Thread starter Maroon5.0
  • Start date Start date Oct 18, 2004
M

Maroon5.0

New Member
Dec 14, 2003
57
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Oct 18, 2004
#1
  • Oct 18, 2004
  • #1
Hey guys, i rebuilt my motor over the summer and did h/c/i i did crane cam with power range of 1500-5500, performer intake, and gt-40p heads and it only peaked at 4850, my question is do you think it peaked so low because i have the stock throttle body and mass air and at the high of rpm it cant get in the needed air to keep making power? Im really not sure and am trying to figure it out so i can atleast peak in the 53-5500 range like i think it should
 
2

2002BLGT

Well-Known Member
Dec 18, 2003
2,945
4
59
Bedford VA
Oct 18, 2004
#2
  • Oct 18, 2004
  • #2
Maroon5.0 said:
Hey guys, i rebuilt my motor over the summer and did h/c/i i did crane cam with power range of 1500-5500, performer intake, and gt-40p heads and it only peaked at 4850, my question is do you think it peaked so low because i have the stock throttle body and mass air and at the high of rpm it cant get in the needed air to keep making power? Im really not sure and am trying to figure it out so i can atleast peak in the 53-5500 range like i think it should
Click to expand...


post the specs on the cam and all that good stuff for more input , MAF and TB could be causes though for sure ......
 
T

tjm73

Founding Member
Aug 3, 2000
2,418
2
48
Rush, NY
Oct 18, 2004
#3
  • Oct 18, 2004
  • #3
Are you looking at the factory tach? If so, forget the numbers as it is notriously inaccurate at higher rpms. I saw over 7000 rpm once in my car and the factory rev limiter never came on. Factory computer limits revs at 6250 rpm, so I was almost 1000 rpm off and still no rev limiter.
 
M

Maroon5.0

New Member
Dec 14, 2003
57
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Oct 18, 2004
#4
  • Oct 18, 2004
  • #4
no im going off the dyno sheets as to where it peaks

heres specs
Basic Operating RPM Range 2,000-5,500 RPM
Intake Duration 050 inch Lift 216
Exhaust Duration 050 inch Lift 220
Advertised Intake Duration 270
Advertised Exhaust Duration 278
Intake Valve Lift with Factory Rocker Arm Ratio 0.533
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.544
 
9

90Notch

Founding Member
Jan 31, 2002
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Westwood, MA & yes it's killing me that I'm no
Oct 18, 2004
#5
  • Oct 18, 2004
  • #5
Did you degree the cam? I'm running a stock MAF and stock TB and I'm peaking at 5200rpm. Post your dyno sheet, I've been loking for a dyno of a 2030.
 
M

Maroon5.0

New Member
Dec 14, 2003
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Oct 18, 2004
#6
  • Oct 18, 2004
  • #6
yeah it was degreed in
 
9

90Notch

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Jan 31, 2002
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Westwood, MA & yes it's killing me that I'm no
Oct 18, 2004
#7
  • Oct 18, 2004
  • #7
Small cam that closes intake early isn't going to be high revver. What was your torque?
 
M

Maroon5.0

New Member
Dec 14, 2003
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Oct 18, 2004
#8
  • Oct 18, 2004
  • #8
torque peaked out at 4000 rpm at about 330ft-lbs
 

TrickStang37

New Member
Oct 17, 2004
292
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0
Oct 19, 2004
#9
  • Oct 19, 2004
  • #9
my e303 peaked at about 5100 (220*/220* .529/.529 runnin 1.7s) with Street Heat intake, TFS heads, 65mm TB and 73mm MAF. So I dont think it sounds too off, if anything i think sounds about right. If you had to pick between the MAF or the TB holdin you back, i would guess MAF. doubt the TB is holding you back much at all. What was your fuel ratio like? stock fuel pump?
 

TrickStang37

New Member
Oct 17, 2004
292
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0
Oct 19, 2004
#10
  • Oct 19, 2004
  • #10
BTW, not all factory tachs are off. Mine was off by about 50 or so RPMs vs my Autometer tach at fuel cut off so i ended up taking out the Autometer.
 
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