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  • Fox 5.0 Mustang Tech

331 stroker w/ AFR165's

  • Thread starter Thread starter 1991vert
  • Start date Start date Aug 28, 2005

1991vert

10 Year Member
Feb 27, 2004
1,103
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Ludlow, MA
Aug 28, 2005
#1
  • Aug 28, 2005
  • #1
would a 331 with afr165's and a novi2000 make good streetable power?

would the HP difference between a 306 and 331 with the same setup be noticeable?

thanks,
chris
 

_jb_

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Mar 4, 2004
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Aug 28, 2005
#2
  • Aug 28, 2005
  • #2
a blown 331 will make more power than a blown 306.
 
F

fiveohh94gt

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Dec 26, 2003
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Aug 28, 2005
#3
  • Aug 28, 2005
  • #3
_jb_ said:
a blown 331 will make more power than a blown 306.
Click to expand...
of course the 331 will make more power, but the question is does it make significatly more power? also how much, if any, will the 165 hold you back with the 331? ttt, i'd like to know this also
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
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89
Dallas, GA
Aug 28, 2005
#4
  • Aug 28, 2005
  • #4
That would be a wicked combo. Of course you might be able to get a couple tenths or so from 185's, but you probally would like the 165's for the street. The 331 might not make much difference top end but there would be a sizable difference down low and in the middle, which is better for the street.
 

5spd GT

"the 5.0 owns all"
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Aug 28, 2005
#5
  • Aug 28, 2005
  • #5
I could be in the same boat later this year. 331 with AFR 165's...i'm subscribing
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
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#6
  • Aug 28, 2005
  • #6
Build the cubes!

The afr 185's will walk all over the 165's from idle to where ever you let off the throttle. But, in this case, the blower will make up for your 'lack of head'. You can have your self a 500rwhp pump gas street car.

Put a rpm II, holley, tfs-r intake on it, custom cam or afm 'hi rev' blower cam, good valve springs, good exhaust (1 3/4" LT's and 3" exhaust) and enjoy. You'll need a big injector. I'd say at least a 55lb.

Last week you were asking about an afr 205 headed 347, now a 165 headed 331. I'm guessing moneys an issue?
 

1991vert

10 Year Member
Feb 27, 2004
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Aug 28, 2005
#7
  • Aug 28, 2005
  • #7
no money really isnt an issue; im buying a dart block...i just dont want another fiasco selling/shipping parts. im just curious and like to ask questions before i go ahead and order parts. a 55lb injector? do they even sell those?
 

bluevenom867

I will have images of molesting stuffed animals in
Dec 15, 2003
1,704
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0
St.Petersburg,FL
Aug 29, 2005
#8
  • Aug 29, 2005
  • #8
1991vert said:
no money really isnt an issue; im buying a dart block...i just dont want another fiasco selling/shipping parts. im just curious and like to ask questions before i go ahead and order parts. a 55lb injector? do they even sell those?
Click to expand...

Yea,MSD makes 55lbs injectors.I think Summit has them on there site.
 

Auto Reverse

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Jul 22, 2003
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Buffalo, NY
Aug 29, 2005
#9
  • Aug 29, 2005
  • #9
One of the Mustang magazines (5.0, I think) did a comparison between the AFR 165's and 185's on a 347 stroker a couple months back. The power was negligible, 17 HP max. Keep in mind this is flywheel too.

Basically, the author and article concluded with, if you already have 165's then keep them. If you don't, then get the 185's.
 
T

tjm73

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Aug 3, 2000
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Aug 29, 2005
#10
  • Aug 29, 2005
  • #10
AFR185 will make more power everywhere on a blown 331.

165's are really best for a 302. On a 331 you can go either way depending on the combo and on a 347 you want the 185.
 
S

strokedandblown

Banned
May 3, 2005
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USA
Aug 29, 2005
#11
  • Aug 29, 2005
  • #11
1991vert said:
no money really isnt an issue; im buying a dart block...i just dont want another fiasco selling/shipping parts. im just curious and like to ask questions before i go ahead and order parts. a 55lb injector? do they even sell those?
Click to expand...

yes they sell 55lbs'ers, find out what boost levels your going to be runnig and how your going to tune the car as well, are you sticking w/the stock computer? are you going pms, stand alone... You also have to look @ the rest of the drive train, trans rear end, If you just building a street car you dont have too much to change but if you want an everything car (tons of hp+tq, drag, street, road course....etc) theres a ton of stuff your gonna have to change. Its gonna be fun the first time you lay into (after the break in period ) dont forget about the fuel system i have all braided lines weldon pump its not cheap either....... ohh the fun
 

5spd GT

"the 5.0 owns all"
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Aug 29, 2005
#12
  • Aug 29, 2005
  • #12
Auto Reverse said:
One of the Mustang magazines (5.0, I think) did a comparison between the AFR 165's and 185's on a 347 stroker a couple months back. The power was negligible, 17 HP max. Keep in mind this is flywheel too.

Basically, the author and article concluded with, if you already have 165's then keep them. If you don't, then get the 185's.
Click to expand...

Interesting...that is probably about the numbers I would have suspected...
 

CoupedUp

Banned
Aug 26, 2005
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0
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Aug 29, 2005
#13
  • Aug 29, 2005
  • #13
Auto Reverse said:
....AFR 165's and 185's on a 347 stroker a couple months back. The power was negligible, 17 HP max. ....
Click to expand...

I can't recall (I'll have to whip out my mag) but weren't the other supporting pieces on the 347 favorable to the smaller 165's as well

I can't remember if the intake and cam were heavy breathing parts
 
T

tjm73

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Aug 3, 2000
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48
Rush, NY
Aug 29, 2005
#14
  • Aug 29, 2005
  • #14
CoupedUp said:
I can't recall (I'll have to whip out my mag) but weren't the other supporting pieces on the 347 favorable to the smaller 165's as well

I can't remember if the intake and cam were heavy breathing parts
Click to expand...

Cam was kinda small. And the intake was Performer RPM II.....I think......
 

1991vert

10 Year Member
Feb 27, 2004
1,103
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Ludlow, MA
Aug 29, 2005
#15
  • Aug 29, 2005
  • #15
so keep the 165's and go with a 347? or just stick with the 331 idea? i guess there's no harm in doing a 331/347 over a 302/306. the cubes will always be there, just just the top end that i may have to change.

ALL SUGGESTIONS ARE WELCOMED.

first time building a motor
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
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Aug 29, 2005
#16
  • Aug 29, 2005
  • #16
The 331 will be better for a supercharger. Less sidewall pressure is one reason for that. If your going N/A and not really a daily driver I would get a 347 personally.

You had good timing with this thread...I think I'll be okay with my AFR 165's for now...when/if I decide to build.
 

1991vert

10 Year Member
Feb 27, 2004
1,103
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Ludlow, MA
Aug 30, 2005
#17
  • Aug 30, 2005
  • #17
seems like a few of us are in the same boat. im goign to be picking up a dart block and my next step after that is the rotating assembly. i dont want to rush into that and end up throwing $1300 down the drain. i dont drive the car a lot, but i want it to last a while. so would a 331 be more suited to me?
 

Grn92LX

Fidanza Man!
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Aug 30, 2005
#18
  • Aug 30, 2005
  • #18
Go 347 either way. With the blower it doesn't matter as much b/c either way you'll still make power even if you use the 331. If you're worried about not enough piston meat with the 347 and blower, use the 5.315" probe rods and probe pistons (which are 331 pistons) giving you a 1.175" CH. If you're going dart block, have the assembly neutral balanced. Make sure whoever you buy the assembly from knows you want a zero balance (neutral) assembly. I do not know if scat or CHP forged cranks can go neutral, thats a Rick 91GT question

Even with the smaller afr 165's, the blower will help 'fix' your lack of cylinder head.
 

CoupedUp

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#19
  • Aug 30, 2005
  • #19
tjm73 said:
Cam was kinda small. And the intake was Performer RPM II.....I think......
Click to expand...

Right ...

Also of interest is from the big Ford cylinder head test MMFF did ... the 165's flow peak cfm around .500" lift on the valve and the 185's peaked around .550".


91 Vert, I suggest you go with a 331 with 5.315 rods from DSS
 
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