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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

331 or 347????

  • Thread starter Thread starter madmax680
  • Start date Start date Aug 23, 2004
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Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Aug 26, 2004
#21
  • Aug 26, 2004
  • #21
Legendary, you'll make goiod power if you give the 331/347 the parts to feed it properly, the entire top half of the motor and CAM is very important to maximizing a combo.
 

Legendary

Founding Member
Oct 10, 2002
1,925
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0
City of Angels
Aug 26, 2004
#22
  • Aug 26, 2004
  • #22
Cool. I don't know anybody with a 331 stroker so I don't really know any proven combinations. In fear of sounding like a noob I must ask: What is the power potenial with the top half I have already with a 331? (well at least I didn't start a thread about it.)
 
N

Nottoofast50

Founding Member
Dec 9, 2000
386
0
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Cali
Oct 11, 2004
#23
  • Oct 11, 2004
  • #23
Rick 91GT said:
A 5500rpm converter has no place on the street


Micheal, we made 465/425 to the wheels @ 5800rpm on a very basic blown 331, 9.6:1comp, Cast iron GT-40's, Extrude Honed Cobra, Crane 2031 cam, stock 1.7 rockers shorty headers, 83mm MAF, 75mm TB, 36# inj, 255lph HP pump, full exhaust and cats, all emissons and cold A/C
Click to expand...


Sorry to dig up an old thread but i was doing some research on stroker kits.... rick 91gt how much boost where you running to make those numbers?
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Oct 11, 2004
#24
  • Oct 11, 2004
  • #24
9.8psi slightly over spinning a A-trim, so the air was hot. We were pretty happy with the results since the combo was fairly simple and emission legal.
 
N

Nottoofast50

Founding Member
Dec 9, 2000
386
0
0
Cali
Oct 11, 2004
#25
  • Oct 11, 2004
  • #25
Thx for the reply.... i'm going with a similar combo and was hoping for 450rwhp with 12 psi.
 

1986LX2002

Founding Member
Aug 15, 2002
317
0
0
Oct 12, 2004
#26
  • Oct 12, 2004
  • #26
I have a stock 5.0 block and wanting to make it a 331. Now some people have told me it has to be bored .30 over and other say i can leave it standard bore. Help me out here.
 

EMW150

Founding Member
May 22, 2000
2,020
1
46
Roaring Spring,PA
Oct 12, 2004
#27
  • Oct 12, 2004
  • #27
1986LX2002 said:
I have a stock 5.0 block and wanting to make it a 331. Now some people have told me it has to be bored .30 over and other say i can leave it standard bore. Help me out here.
Click to expand...

It depends on the condition of the block. You could stay standard bore if the bores are perfect but unless the block is new I'd say they're not perfect. Better off to bore it in most cases. A standard bore 3.25 stroke would be like 327 inches.
 

Legendary

Founding Member
Oct 10, 2002
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City of Angels
Nov 16, 2004
#28
  • Nov 16, 2004
  • #28
Gotta dig this up. I came across a friend of a friend that would port my GT-40 iron heads for about 400. Would this port job be good enough for the 331 and keep street driving possible?
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Nov 16, 2004
#29
  • Nov 16, 2004
  • #29
Not sure how we're gonna know anything at all about the quality/performance of a port job your friend of a friend does.
 

EMW150

Founding Member
May 22, 2000
2,020
1
46
Roaring Spring,PA
Nov 16, 2004
#30
  • Nov 16, 2004
  • #30
Legendary said:
Gotta dig this up. I came across a friend of a friend that would port my GT-40 iron heads for about 400. Would this port job be good enough for the 331 and keep street driving possible?
Click to expand...

As Michael Yount pointed out we can't vouch for the port job but decently ported GT-40 irons should work pretty descent on it for a somewhat mild street build. You'll have to keep compression down a bit from what you could run with aluminum but it should still perfom pretty well. Alot depends on what cam combo, etc. you want to run with it.
 

Legendary

Founding Member
Oct 10, 2002
1,925
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0
City of Angels
Nov 16, 2004
#31
  • Nov 16, 2004
  • #31
Well I just emailed Thumper and asked him about porting them. As long as I can get a good running everyday driving street motor I'll be good.

So running the ported irons I'll have to keep compression down?
 

EMW150

Founding Member
May 22, 2000
2,020
1
46
Roaring Spring,PA
Nov 16, 2004
#32
  • Nov 16, 2004
  • #32
Legendary said:
Well I just emailed Thumper and asked him about porting them. As long as I can get a good running everyday driving street motor I'll be good.

So running the ported irons I'll have to keep compression down?
Click to expand...

I've heard good things about Thumper's work. Run the compression question by him since he has more experience with Iron Heads, he won't steer you wrong. I'm going to say you'll probably want to be under 10.5:1.
 
M

mcchargue

New Member
Nov 12, 2004
2
0
0
Central NC
Nov 16, 2004
#33
  • Nov 16, 2004
  • #33
You maybe really pushing it on pump gas at 10.5:1, unless you run the motor pretty cold (160 thermostat). You probably won't be able to run much timing. I am running GT-40P's at about 9.7:1 and they will rattle a little if it get above 185 degrees on 93 octane. They seem to work OK with only 10 degrees initial timing, which helps.
 
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