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crate motor bugs....

  • Thread starter Thread starter RayzLX
  • Start date Start date Mar 29, 2006
R

RayzLX

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Dec 28, 2001
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Mar 29, 2006
#1
  • Mar 29, 2006
  • #1
I gave my nephew my 90 notch about 10 months ago. He ordered a new crate gt40 motor from ford racing and it having a dealership in Utah do the install. The dealership has had the car for about 4 weeks, yesterday they finally told him it was ready. He called me last night and said it has a lopey idle (he could probably live with this.. I don't know if that is normal for one of these 'performance' motors).

The problem (and the dealership agrees this is a problem) is this... The motor is really starved for fuel when he pushes the accelorator. The dealership has replaced everything from the fuel pump to throttle body, the injectors.. everything except the computer. They are saying this is the computer is the problem.

I think they are feeding him a line of bull****, but I am in another state, can't hear it run, etc.

for anybody who has gone through this swap, what did you do for your computer, anything?
 

just4bob50

Active Member
Apr 2, 2005
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Mar 29, 2006
#2
  • Mar 29, 2006
  • #2
Did the dealer ship replace those parts with stock parts. If so there may not be any improvement at all. He may need parts like a bigger fuel pump, larger injectors or maybe just an adjustable fuel press. regualator. If there is a performance shop local to him it may be in his best interest to take it there if they have a good rep. They can make sure everyhthing is set up right and recommend proper parts.
 

Modular2v

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Jun 30, 2002
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Mar 29, 2006
#3
  • Mar 29, 2006
  • #3
the car might need a tune also
 

jrichker

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Mar 29, 2006
#4
  • Mar 29, 2006
  • #4
If the crate motor that was ordered is over 300 flywheel HP, you need 24 Lb injectors, a 112 LPH or larger fuel pump and a MAF calibrated for the 24 LB injectors. The stock fuel system & injectors are limited to 300 HP or maybe a very small amount more.

The stock computer will adapt to run an engine with much more power than 300 HP. It just needs the proper MAF & fuel system to do it.
 
R

RayzLX

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Dec 28, 2001
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Mar 29, 2006
#5
  • Mar 29, 2006
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will check!

Thanks for the replies.. I will check with my nephew this afternoon on the specifics of the injectors. That does ease my fears on the computer as being the culprit!

I know they installed a new highflow fuelpump, and assume the correct injectors were also put in, but don't know. Here is what I do know, it cost him over 5 g's in extra parts and labor. That is on top of the price of the motor which was 4 g's.

I let him know he may end up with a fox for the price of a viper!!
 
R

RayzLX

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Dec 28, 2001
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Mar 30, 2006
#6
  • Mar 30, 2006
  • #6
Ok, so I talked with my nephew, he doesn't know any specifics of what they installed. Fuel pump specifics, injector specific or MAF. I am going to call the dealer and find out what they installed and re-post. I am sure they is going to feed me the BS about the computer not being able to handle it.

He did go with the 345 horse ford racing motor.

Who has gone through this motor swap??
 

Modular2v

Founding Member
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oklahoma
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#7
  • Mar 30, 2006
  • #7
this motor swap should be a breeze...something is up
 
R

RayzLX

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Mar 30, 2006
#8
  • Mar 30, 2006
  • #8
one more update...

ok, talked with the mechanic, he has been pulling his hair out with this install. The dealership has not installed one of these motors before, so I understand there is a little learning curve.

Here is what he said they have installed. He did verify that they did install a high volume fuel pump. He did install 30lb injectors. And he tried to install a 90 mm Mass Air Sensor, but it ran so bad..... they reverted back to stock!

He said the codes they were getting was that the motor was still running lean.

So, He has basically exhausted everything he knows to try and has basically just given up, and said he( my nephew) needs to take it to a performance shop that can "re-calibrate" the computer. He had also heard that the computer 'should' be able to handle the horse power but his experience tells him otherwise.

jrichter, What do you mean by a MAF calibrated for 24lb injectors? Maybe that is the problem. When you order, you specify your injector size?


I appreciate any feedback, or ideas.
 
M

Mike92GT

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Jan 23, 2002
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Florida
Mar 30, 2006
#9
  • Mar 30, 2006
  • #9
If he's running 30lb injectors with the stock mass air meter then it's time for a new mass air meter. When changing injectors, you have to replace or recalibrate the mass air meter as well. Look into either a C&L meter or Pro-M www.massairsystems.com
 
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