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85 5.0 HO question

  • Thread starter Thread starter BullittStangV8
  • Start date Start date Apr 16, 2006

BullittStangV8

Founding Member
Oct 5, 2002
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Apr 16, 2006
#1
  • Apr 16, 2006
  • #1
Guys,
I'm looking at a 1985 5.0 HO motor. Someone I know may be selling one, and I need a good solid foundation for a 5.0 based motor build up. Is the 85 5.0 HO a good year to use? I most likely would only be using the block, and any possible external accessories. I would be going with a 5.0 punched and stroked out to a 331, with AFR 185 heads on it. The motor is without a carb, but with an intake, and is complete besides that. Does this block have a roller cam? The owner said it might have a E- cam in it..Hows that cam for performance? How much HP can the block take if I throw an aftermarket girdle on it? And last...but not least...whats a fair price for it? (millage is unknown, but its claimed to turn over freely).
 

Realmongo

I prefer to be called "Evil Genius"
Founding Member
Oct 10, 2001
2,468
86
99
Western Mass
Apr 16, 2006
#2
  • Apr 16, 2006
  • #2
No the 1985 block is not that good. It is just a 1984 block with modifications for the roller camshaft. It has the same thin cylinder walls, bulkheads and deck surfaces. The better block to use is the E7TE casting or the F1 casting with the deeper main stud holes.
 

txstang84

15 Year Member
May 21, 2005
1,639
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69
Tuscola, tx
Apr 16, 2006
#3
  • Apr 16, 2006
  • #3
that's a new one on me, I've seen several people using the E5SE casting with no problems...as for the main bolt holes-where are you getting that one? You can use any kind of quality aftermarket fastener that the later models use-they'll fit into a any 289 or 302 casting. Case in point; I just pulled my old motor out last week-a mexican b-equipped with ARP main studs...no problems there...they threaded in the full way-and they are blind bolt holes.

As far as the cylinder wall thickness...it's a crapshoot-it doesn't matter what year the block was cast in-all windsor blocks including 351's are thinwall castings-the only way you'll find a "thicker" one is to be very selective and bring along a sonic tester (if you've a a grand to spare and buy one) and ck every block you run across.

Also, on the main stud holes; Since we all know that factory roller blocks are not what we like to call strong blocks, wouldn't it make sense to find one with more material as opposed to more holes?
 

txstang84

15 Year Member
May 21, 2005
1,639
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69
Tuscola, tx
Apr 16, 2006
#4
  • Apr 16, 2006
  • #4
perhaps I should stand corrected; According to my Mustang Performance Handbook (I felt compelled to ck out what it said), the author says, "Although a vast improvement over previous years, this roller cam block is weak, has poor heads and has low-compression."

He goes on to mention that '86 model blocks have semi-siamesed cylinders and would be considerably stronger.

...however, in the past I've found certain things published to be anywhere from slightly inaccurate to dead wrong...

Honestly, unless you're looking to get above 400hp, then you really shouldn't have to worry, all roller blocks are sufficient at best until you start breaking 400-450 range, then you really need to start looking into a new block.

Just keep your bottom end balanced, use quality components, and keep the power output reasonable, and you should be good to go...
 

BullittStangV8

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Oct 5, 2002
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Apr 16, 2006
#5
  • Apr 16, 2006
  • #5
Well I'm looking to make 400-430 FWHP..So I guess this isnt the best choice for building a motor off of. What year 5.0 would be the best?
 

txstang84

15 Year Member
May 21, 2005
1,639
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Tuscola, tx
Apr 16, 2006
#6
  • Apr 16, 2006
  • #6
400-430 is getting kinda close to splitting territory based on what most people believe...

If you don't mind spending the moolah, get a better block...we all know that if you get the horsepower level you're seeking, you'll eventually want more...horsepower is addictive!

you could always go 351, unless you're dead set on a 302 derivative
 

BullittStangV8

Founding Member
Oct 5, 2002
1,104
0
36
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Apr 16, 2006
#7
  • Apr 16, 2006
  • #7
Nope. I'm most likly going 351 anyways. I just almost stumbled on to the 302, and I was thinking it could have been a cheaper alternative. The hard part is that I cant find a 351 around me....
 

txstang84

15 Year Member
May 21, 2005
1,639
42
69
Tuscola, tx
Apr 16, 2006
#8
  • Apr 16, 2006
  • #8
seriously? Where's the nearest junk yard to you? Well, you could always try eBay, or start off fresh with a new b-I think 351 sportsman blocks are about a grand...but it would handle substantially more power than a 2-bolt 302 ever could...

as far as the parts, assuming you started out fresh with each motor, part for part, the 351's components really aren't any more expensive than a 302...

Think of it this way...you stroke a 351, you could get 408 cubes
 
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