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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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what's the horsepower differences betweem 306/331's

  • Thread starter Thread starter tvmango
  • Start date Start date Dec 24, 2003

tvmango

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Oct 27, 2003
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bradenton florida
Dec 24, 2003
#1
  • Dec 24, 2003
  • #1
I know your probably sick of hearing from me, but what's the big power difference In these 2 blocks? I am just wondering if it's worth all the extra money..
 

Deths91Gt

Founding Member
Sep 30, 1998
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Dec 24, 2003
#2
  • Dec 24, 2003
  • #2
Same b--just one has a 3.25 stroke--and its not just the extra CI but what you have to support it and its goal. But im sure a 331 will make more power then a 306 if they have the same combo.
 

tvmango

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Oct 27, 2003
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bradenton florida
Dec 24, 2003
#3
  • Dec 24, 2003
  • #3
I know the differences, thank you though, I was just wodering of the 331 made a ton more power, for all the extra money, and parts..flexplate ,damper etc..
 

Deths91Gt

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Sep 30, 1998
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Dec 24, 2003
#4
  • Dec 24, 2003
  • #4
It really depends on what you have done to it--im sure no one that builds a 331 or a 347 would use heads that wasnt meant for it--like stockers--but most 331's are built to rev to the moon or run alot of boost--so i would say yes and no to your question.
 

tvmango

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Oct 27, 2003
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bradenton florida
Dec 24, 2003
#5
  • Dec 24, 2003
  • #5
that's my problem, it's really a big price difference, with all the extra's. and as you can see all i have to put on in my signature..So i need to get whatever with give me the most for my buck.. A really good 306 is 2k$$ But a really good 331 with balancer and flywheel is 3k
 

Deths91Gt

Founding Member
Sep 30, 1998
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Dec 24, 2003
#6
  • Dec 24, 2003
  • #6
I have a few friends that have made over 500 at the wheels with a 306--built properly. Its amazing what boost will do!!
 

tvmango

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Oct 27, 2003
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bradenton florida
Dec 24, 2003
#7
  • Dec 24, 2003
  • #7
oh yeah.... I will call chp and dss friday and see what they have to say.. i want to order it asap. i was hoping to get my engine together by the end of the year, but my stock block, had on of the trany mount ears broken off, really great.. so I'm at sqaure one with no money..
 

tvmango

New Member
Oct 27, 2003
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bradenton florida
Dec 24, 2003
#8
  • Dec 24, 2003
  • #8
tvmango said:
oh yeah.... I will call chp and dss friday and see what they have to say.. i want to order it asap. i was hoping to get my engine together by the end of the year, but my stock block, had on of the trany mount ears broken off, really great.. so I'm at sqaure one with no money..
Click to expand...
heres the picture..
 

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DemonGT

Founding Member
May 24, 2002
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Sparta,WI
Dec 24, 2003
#9
  • Dec 24, 2003
  • #9
i suggest giving Keith Craft a call also
 
1

1bad92lx

New Member
Mar 31, 2003
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Close to lynchburg, VA
Dec 24, 2003
#10
  • Dec 24, 2003
  • #10
Hey demon, what does your car run at the track... I'm just curious because my uncle has a similar setup going in his car.

thanks,

Matt
 

DemonGT

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May 24, 2002
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Sparta,WI
Dec 25, 2003
#11
  • Dec 25, 2003
  • #11
dont know yet...just got it running before i put it away for winter...and spring time ill be doing a tranny and clutch swap then a fuel system upgrade..so it wont be till late summer at best that i see what it can do
 

86Cobra

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Jun 6, 2000
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Phoenix, AZ
Dec 25, 2003
#12
  • Dec 25, 2003
  • #12
A good rule of thumb is one hp per cubic inch extra. So, on average, a 331 will make 25 more hp than a comparable 306.

But, it all depends on the combination. A properly setup 306 can easily outpower a mismatched 331 combo. I know this from experience.
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
Aug 10, 2002
9,457
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Ontario, Canada
Dec 25, 2003
#13
  • Dec 25, 2003
  • #13
Let's not forget the added torque gained by the extra displacement. I remember reading an article that MM&FF did a few years back. They took two identical cars and built the engines almost exactly the same, with the exception that one was a 302 and one was a 331. The end result was that the stroker made an additional 52lbs/ft of torqe at the flywheel. That alone is worth the money.

A 331 would be the cat's meow, combined with the parts in your sig.
 

tvmango

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Oct 27, 2003
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bradenton florida
Dec 25, 2003
#14
  • Dec 25, 2003
  • #14
thanks guys...
 
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