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5.0 vs. 5.0 HO

  • Thread starter Thread starter blackLX_92
  • Start date Start date Sep 26, 2007
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blackLX_92

New Member
Sep 26, 2007
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Sep 26, 2007
#1
  • Sep 26, 2007
  • #1
whats the diffrence in the 5.0 and the 5.0 HO i mean i know the fireing order is diffrent but other than that are they basically the same

and i have a 92 LX that has the 5.0HO pulled out and a carbed reg. 5.0 in it
the reg. 5.0 has been shaved and a roller valve train stock cam i have a E303 but dont know if itll work in it cuz of the diffrent fireing order...i might be able to get my hands on a HO but im gunna switch that HO to a carb...should i through out the reg. 5.0 and get the HO or is it worth it?? this is my first stang and i want it to screem ....so far it has 4.10 gears,tubeular upper and lower contol arms, short through shifter, holley electric fuel pump and regulator, MSD ignition, accel coil, ford racing 9mm plug wires, edlebrock performer 289 intake, full ford racing roller valve train, and a holley 600 cfm carb but im getting my new edlebrock this weekend!!!!!
 

87foxstang

Member
May 10, 2007
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16
Cromwell, CT
Sep 26, 2007
#2
  • Sep 26, 2007
  • #2
im not sure about all the differences in the two but i know the intake faces left lol. I would go with the HO
 

samickguy15

Member
Sep 1, 2005
404
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16
Delavan, IL
Sep 26, 2007
#3
  • Sep 26, 2007
  • #3
If the 5.0 has been converted to roller then it is basically an HO.

When you swap an HO style cam for a standard cam or vice-versa all you have to do it switch your plug wires around. So that's not a big deal.
 
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blackLX_92

New Member
Sep 26, 2007
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Sep 26, 2007
#4
  • Sep 26, 2007
  • #4
samickguy15 said:
If the 5.0 has been converted to roller then it is basically an HO.

When you swap an HO style cam for a standard cam or vice-versa all you have to do it switch your plug wires around. So that's not a big deal.
Click to expand...

what about the crank ... what you said i dont think would work id have to get an HO crank right?
 

Fast63

New Member
Sep 20, 2007
717
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Sep 26, 2007
#5
  • Sep 26, 2007
  • #5
All 302 cranks are the same as far as that goes. When the firing order was changed, it just swapped cylinders that both came to TDC at the same time. Observe:

HO firing order: 13726548
old firing oder: 15426378

1, 2, 6 and 8 are in the same place. 3,7 and 5,4 were swapped, and in the rotation, they correlate with each other as pistons that come to TDC at the same time. 5 and 3 do and 7 and 4 do, so you won't have any piston to valve contact problems.
 

LordMustangGT

Member
Jan 9, 2006
118
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17
Port Orchard, WA
Sep 26, 2007
#6
  • Sep 26, 2007
  • #6
ok ok, I took a 5.0 out of a 86 t-bird and put it in my 88 5.0, only thing that has to be changed it the cam. I took the HO cam out of my blown HO and put it in the Non-HO and runs like a champ. The firing orders are different is all. Same crank and rods, but had the flat-top pistons and the E6 heads.

Matt
 
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facemelter71

New Member
May 29, 2006
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cincy
Sep 26, 2007
#7
  • Sep 26, 2007
  • #7
HO cam wont work in A non HO block without the correct lifters dog bones and retainer for the lifters,unless you find a set that have a guide bar installed.If not then you have to drill and tap holes in the lifter valley to use a roller cam in a non roller(non HO) block.Some thunderbirds came with a HO roller engine.
 

cenok is family

15 Year Member
Jun 25, 2003
1,409
69
79
Norman, Ok
Sep 26, 2007
#8
  • Sep 26, 2007
  • #8
the intake in non-HO cars was more restrictive too, but you said your car's carbed so that doesn't matter for you.
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
Jul 1, 2005
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Apache Junction, AZ
Sep 26, 2007
#9
  • Sep 26, 2007
  • #9
I think there's a bit of confusion with what some here are considering a non-HO 5.0. From '86 to '90, the lo-po 5.0 and the HO 5.0 were the same BLOCK - both were rollers, same crank, same rods. As stated, the pistons were different, as were the cam, heads (E6 versus E7), UPPER intake manifold (lower was the same for both), EGR spacer, throttle body, ECM, fuel rail, and injectors.

Swapping a non-HO to HO specs involves swapping most of the above. The HO upper intake will actually mount backwards onto the lower manifold without any modifications, although you'd need to flip-flop the butterfly on the throttle body, and either bore out the old EGR spacer or bypass the coolant lines on an HO spacer, if using an HO in a non-HO application, such as a Crown Victoria.

The "old" 5.0 that others may refer to are the old non-roller blocks (pre-85, I think), which are a completely different animal in a lot of ways. Different fuel delivery system, different heads, pistons, cam, etc.
 

vristang

15 Year Member
Mar 31, 2005
4,933
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124
Seattle
Sep 26, 2007
#10
  • Sep 26, 2007
  • #10
Although it doesn't pertain to the Original question, others have hinted to it...

The ecu used on the HO cars is different than non-HO.

The HO ecu (as found in a 88-93 Mustang 5.0), uses the HO firing order to fire the Injectors Sequentially.
Using a non-HO cam with an HO ecu, will result in issues...

http://www.fordfuelinjection.com/?p=92

jason
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
Jul 1, 2005
314
281
134
Apache Junction, AZ
Sep 26, 2007
#11
  • Sep 26, 2007
  • #11
*ahem* Already specified two posts above that the ECM needs to be swapped over when going from lo-po to HO 5.0. But good info, anyway...
 

LordMustangGT

Member
Jan 9, 2006
118
0
17
Port Orchard, WA
Sep 26, 2007
#12
  • Sep 26, 2007
  • #12
the no-ho block all I had to do was swap to a HO cam. It was already roller.
 
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facemelter71

New Member
May 29, 2006
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cincy
Sep 27, 2007
#13
  • Sep 27, 2007
  • #13
Then that block came from a roller 85 or 86 with the flat top pistons.So then it was an HO engine.
 
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