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351W engine plan

  • Thread starter Thread starter COBRAIIW
  • Start date Start date Jan 27, 2006
C

COBRAIIW

New Member
Apr 26, 2003
562
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Jan 27, 2006
#1
  • Jan 27, 2006
  • #1
Time to start planning out a 351W build using what I have.
Got a running '78 351W, with an offenhauser intake, otherwise stock.
Got a running '86 5.0 HO roller motor with 10-1 comp., 1.6-1 rollers, street/strip cam (no idea of the lift/durations) larger valves in these home ported heads. stock '86 5.0 I believe.

I want to go with a roller cam, and street/strip applications.
Can I use the 5.0 heads, and pistons?

Stroking is out of my budget right now, but I am considering nitrous in the future.

Any wise advice ?
 

393 Boss

20+ Year Stangneter
Dec 24, 2004
107
5
18
HU
Jan 28, 2006
#2
  • Jan 28, 2006
  • #2
COBRAIIW said:
Any wise advice ?
Click to expand...

Going 351W is a great way to go but... how about a pair of blown twin 351W engines instead???... just need a bit of a custom frame job

Hey!... it's been done lol.
http://www.mustangandfords.com/featuredvehicles/30698/
 
C

COBRAIIW

New Member
Apr 26, 2003
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Jan 28, 2006
#3
  • Jan 28, 2006
  • #3
A little bit out of budget too!
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
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58
NE Ohio
Jan 28, 2006
#4
  • Jan 28, 2006
  • #4
COBRAIIW said:
A little bit out of budget too!
Click to expand...


Volume discount.?

Try to find a Buy three get one free sale.
 

bennettracing

Founding Member
Aug 26, 2002
280
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Ava, MO
Jan 28, 2006
#5
  • Jan 28, 2006
  • #5
I'm not too sure, but I believe that only applies to tire sales

whats up everybody, long time no see
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
3
58
NE Ohio
Jan 28, 2006
#6
  • Jan 28, 2006
  • #6
bennettracing said:
I'm not too sure, but I believe that only applies to tire sales
Click to expand...

Which would be needed with a W per tire.


whats up everybody, long time no see
Click to expand...

Not much, You?

Completed my second degree, starting work on the third.
 
M

myfirstii

Founding Member
Feb 28, 2002
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Jan 29, 2006
#7
  • Jan 29, 2006
  • #7
Sorry Im not trying to steal the thread....but Bennettracing Im Also in Carbondale Il. At SIU attending the Automotive program. If you have your car down here we should get together sometime.
Pat
 

bennettracing

Founding Member
Aug 26, 2002
280
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Ava, MO
Jan 29, 2006
#8
  • Jan 29, 2006
  • #8
Mark, you seem to be making a career out of college, which isn't too bad a deal, but the paychecks are kinda rough in that line of work. Pat, I actually just graduated in december and moved to southern Missouri to get a real job, gotta start making some money, it's good to see there's a II in c'dale though.

Back to CobraIIw's question, I believe you can use the 5.0 heads if you wanted to (it's been a while, so Mark, correct me if I'm wrong) But since you don't know the specs on them, I would suggest doing some work on the 351W heads and going with them, or just save up your money, because it's an expensive project one way or another.

Kyle
 

Blue Thunder

15 Year Member
Mar 20, 2004
1,003
55
68
Upstate New York.
Jan 29, 2006
#9
  • Jan 29, 2006
  • #9
In order to bolt the 302 heads onto a 351W block, you would need to drill out the bolt holes in the heads to 1/2" diameter, because the stock bolt holes are factory drilled to accept the 302's 7/16" head bolts.
For any kind of performance, you'll need better heads on a 351W anyway, at least a set of '69-'74 351W heads.
 
C

COBRAIIW

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Apr 26, 2003
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Jan 29, 2006
#10
  • Jan 29, 2006
  • #10
That's what I was planning, drilling the 302 heads, they are fittedwith larger valves and have a roller rocker ratio 1.6-1
what cam and pushrod/lifters would you recommend?
how much trouble to swap the 351W pistons for the 302 10.5-1 pistons?
do the 302 pistons have a different rod end connection than the 351W?
 
1

1badII

Member
Aug 5, 2003
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Durham, North Cacalaky
Jan 30, 2006
#11
  • Jan 30, 2006
  • #11
Neither the 78 351 heads nor the 86 heads are worth a damn, unless the guy that ported the 86's knew what he was doing and ported the hell out of them, including a lot of chamber work.
 

Blue Thunder

15 Year Member
Mar 20, 2004
1,003
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68
Upstate New York.
Jan 31, 2006
#12
  • Jan 31, 2006
  • #12
Yeah, '86 302 heads are the worst ones to start with. '78 351W heads are identical to standard 302 heads in terms of flow, the only difference is a huge combustion chamber.
Speaking of combustion chambers, If you do get a set of 302 heads bolted to a 351W, I'd imagine the compression ratio will be high enough(or perhaps too high) for the limits of premium pump gas, without even changing the pistons.
 
C

COBRAIIW

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#13
  • Jan 31, 2006
  • #13
Hmm...
Take the 351W heads and port them, and use the roller rockers from the 302.
Trying to find a good set of DOOE heads from a '69 351W is darned impossible and most likely pricey.
 
1

1badII

Member
Aug 5, 2003
796
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Durham, North Cacalaky
Feb 1, 2006
#14
  • Feb 1, 2006
  • #14
COBRAIIW said:
Hmm...
Take the 351W heads and port them, and use the roller rockers from the 302.
Trying to find a good set of DOOE heads from a '69 351W is darned impossible and most likely pricey.
Click to expand...
Just go with some GT40's or E7's from www.thumperoforangepark.com.
 

Blue Thunder

15 Year Member
Mar 20, 2004
1,003
55
68
Upstate New York.
Feb 1, 2006
#15
  • Feb 1, 2006
  • #15
COBRAIIW said:
Hmm...
Take the 351W heads and port them, and use the roller rockers from the 302.
Trying to find a good set of DOOE heads from a '69 351W is darned impossible and most likely pricey.
Click to expand...

D0 = 1970, C9=1969. In this case, they're virtually identical heads, with possible slight variation in chamber sizes. The bigger valve/larger intake port 351W heads were produced from '69 to '74.(and maybe some of '75, too) And you're right, they are getting pretty hard to find these days. I bought mine years ago for $50, back when the old 351W head ported on the exhaust side was the way to go for a performance street 302. You can find good used aftermarket heads nowadays pretty cheap.
 
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