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345hp crate engine won't run/idle

  • Thread starter Thread starter Mattys5Oh
  • Start date Start date May 4, 2005
M

Mattys5Oh

Founding Member
Sep 28, 2002
216
0
0
Western, Mass
May 4, 2005
#1
  • May 4, 2005
  • #1
Well I'll give a little background. A friend of ours with more money then knowledge purchased a very over-priced crate engine from Mustangs unlimited. After he everything he paid $3500. it's a 345hp SVO GT-40X crate engine with a B cam.

Well long story short we swapped engines in his 1991 LX notchback with an AOD. We can not get this to idle at less then 900rpm (it takes ALOT of work to get it that low) and as SOON as it's removed from park it dies. We thought that it may have been right up against the converter but MU claims that it should not be a problem. So we are basically at a loss.

What sort of ideas can you guys come up with? Thanks!
 
B

BaXTeR3221

Member
Jan 12, 2004
917
0
16
Orange County, NY
May 4, 2005
#2
  • May 4, 2005
  • #2
900 isn't really too high for the idle.
 

I_AM_CANADIAN

Member
Mar 30, 2005
189
0
16
B.C.
May 4, 2005
#3
  • May 4, 2005
  • #3
BaXTeR3221 said:
900 isn't really too high for the idle.
Click to expand...

that may be so, but there is a reason why it isn't running right and it could affect other things down the road.
 
M

Mattys5Oh

Founding Member
Sep 28, 2002
216
0
0
Western, Mass
May 4, 2005
#4
  • May 4, 2005
  • #4
BaXTeR3221 said:
900 isn't really too high for the idle.
Click to expand...

Don't forget the part that as soon as you take it out of park, it dies.
 
S

SamSnyder

New Member
Mar 30, 2005
196
0
0
May 5, 2005
#5
  • May 5, 2005
  • #5
I made the mistake of using Felpro racing intake manifold gaskets that had oversized port holes (I think the PN was 1250) on a crate motor with GT40 iron heads and stock intake manifold. The mismatch allowed air to be sucked into the intake ports under the manifold. This caused a high and soft idle. You may also want to hunt for vacuum leaks, including bad, loose or missing hose connections.
 
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