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GT40y's good? bad?

  • Thread starter Thread starter 1fastsn95
  • Start date Start date Sep 9, 2007

1fastsn95

New Member
Apr 22, 2005
122
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0
Carthage, tn
Sep 9, 2007
#1
  • Sep 9, 2007
  • #1
ok Im assembling a fresh 308. I have ready to install a B303 cam, cobra intake, 70mm TB, and the usual bolt ons. I just bought a set of y303 heads off ebay. What can I expect? Its mostly a steet car but will see some 1/8 mile strip runs. I dont think I overpaid @ $600 shipped. Or did I? And what size Rockers should I run with this set up?? Thanks! CM
 

jtfairlane

New Member
Mar 5, 2006
468
3
0
Sep 9, 2007
#2
  • Sep 9, 2007
  • #2
Isn't this a question you ask BEFORE buying something?

The GT-40Y heads are probably some of the most modest flowing aluminum sbf heads out there.

Let's put it this way, 99% of people on these boards would say that the GT-40X heads are a waste of money compared to an AFR 165/185 or a Trick Flow Twisted Wedge for the amount of performance you are getting for your dollar. Well, the GT-40Y's flow less than the GT-40X.

I don't know what you mean by what "size" rocker arm you should use, do you mean what ratio?

The GT-40Y heads are pedestal mount heads, so use pedestal mount aka. bolt down rockers. 1.6 is the stock ratio. You can use 1.7 ratio rockers if you wish for increased lift.

I think that, for the price you paid, you could get a decent head by having them ported by a reputable shop, and probably break even with what you would have paid for a better head.
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
Aug 10, 2002
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Ontario, Canada
Sep 9, 2007
#3
  • Sep 9, 2007
  • #3
Wow....not to sound like too much of a smart ass, but after reading this post, it made me think that this might have been a regurgitated question from the mid/late-90's coming back to haunt us? The parts you listed were top of the heap about 10+ years ago, but there are much better parts floating around out there now than the ones you're using in your assembly.

Quite honestly....I wouldn't expect much more than about 265RWHP with that set up....and that's being generous.
 

1fastsn95

New Member
Apr 22, 2005
122
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0
Carthage, tn
Sep 9, 2007
#4
  • Sep 9, 2007
  • #4
Gearbanger 101 said:
Wow....not to sound like too much of a smart ass, but after reading this post, it made me think that this might have been a regurgitated question from the mid/late-90's coming back to haunt us? The parts you listed were top of the heap about 10+ years ago, but there are much better parts floating around out there now than the ones you're using in your assembly.

Quite honestly....I wouldn't expect much more than about 265RWHP with that set up....and that's being generous.
Click to expand...

lol I agree. These are older parts. But they are tried and true right? And Im trying to get as much as I can under a small budget.
 

enyawix

Member
Dec 18, 2005
507
0
19
127.0.0.1
Sep 9, 2007
#5
  • Sep 9, 2007
  • #5
Gearbanger 101 said:
Wow....not to sound like too much of a smart ass, but after reading this post, it made me think that this might have been a regurgitated question from the mid/late-90's coming back to haunt us? The parts you listed were top of the heap about 10+ years ago, but there are much better parts floating around out there now than the ones you're using in your assembly.

Quite honestly....I wouldn't expect much more than about 265RWHP with that set up....and that's being generous.
Click to expand...

true but when is your ford no longer a ford
 

ninety15.0

New Member
Mar 10, 2004
1,336
0
0
Sep 10, 2007
#6
  • Sep 10, 2007
  • #6
I wouldn't worry about it man...those heads will be fine. They flow just as well if not a little better than the GT-40p heads that everyone on stangnet raves about. The B-cam is alright...and the cobra intake is tried and true...and makes the nicest Torque curve and low end Hp out of all the intakes out there. Your combo will be a nice little street setup. Like they said i wouldn't expect to throw down anymore than 260rwhp but it will be a fun street car.

I get sick of sooo many people on stangnet saying that if you cant afford 1300 bucks for AFR's or TFS heads then you shouldn't even consider it. 600 bucks for some nice AL heads is a decent price. If you can afford to get them ported...all the better. Dont skimp out on the valvetrain...thats one of the most important...and consequently expensive parts of the engine. I tried to spend as much as i could afford here. Good luck
 

NKau

Founding Member
Dec 15, 2001
1,346
0
37
Jefferson, WI
Sep 10, 2007
#7
  • Sep 10, 2007
  • #7
ninety15.0 said:
I wouldn't worry about it man...those heads will be fine. They flow just as well if not a little better than the GT-40p heads that everyone on stangnet raves about.
Click to expand...

Couldn't have said it better myself. Pretty much every aluminum head offered today is better than the Y's, but they will still be a big improvement over the E7's and I'm sure you'll be happy with them.
 
5

5.0ina66

Member
Jun 6, 2003
664
0
16
Ohio
Sep 10, 2007
#8
  • Sep 10, 2007
  • #8
NKau said:
Couldn't have said it better myself. Pretty much every aluminum head offered today is better than the Y's, but they will still be a big improvement over the E7's and I'm sure you'll be happy with them.
Click to expand...

Holy *****, it's NKau! Did you sell the 65 or something? Haven't seen you on VMF in a loonnng time.

Oh yeah, might as well keep on topic. The GT40Ys are lukewarm. Positively tepid.
 

NKau

Founding Member
Dec 15, 2001
1,346
0
37
Jefferson, WI
Sep 10, 2007
#9
  • Sep 10, 2007
  • #9
5.0ina66 said:
Holy *****, it's NKau! Did you sell the 65 or something? Haven't seen you on VMF in a loonnng time.

Oh yeah, might as well keep on topic. The GT40Ys are lukewarm. Positively tepid.
Click to expand...

Hey. Yeah, the '65 went down the road about a year ago now. The car had basically just been sitting for the last few years since I bought the '93, and I realized it would be a very long time before I ever would get the time/finances to finish that car the way I wanted to in addition to rebuilding the notch. I haven't been over on the VMF site for quite some time; should probably stop back and say hi
 

enyawix

Member
Dec 18, 2005
507
0
19
127.0.0.1
Sep 11, 2007
#10
  • Sep 11, 2007
  • #10
What are the best "FORD" 302/351 heads?
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
Aug 10, 2002
9,457
1,377
234
Ontario, Canada
Sep 11, 2007
#11
  • Sep 11, 2007
  • #11
enyawix said:
What are the best "FORD" 302/351 heads?
Click to expand...

On a street car, the AFR 165/185's seem to be top of the heap.
 

enyawix

Member
Dec 18, 2005
507
0
19
127.0.0.1
Sep 11, 2007
#12
  • Sep 11, 2007
  • #12
yes the AFR rocks but is is not made by ford.
 
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