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Going from 302 to 306.. a big difference?

  • Thread starter Thread starter dkhl
  • Start date Start date Sep 19, 2004
D

dkhl

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Aug 22, 2004
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Sep 19, 2004
#1
  • Sep 19, 2004
  • #1
I'd like to know what kind of power I would get from simply boring the engine 30 over..

thanks
 
S

Scorcher2005

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Apr 17, 2004
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Sep 19, 2004
#2
  • Sep 19, 2004
  • #2
boring a stock engine over 30? if so, you wont gain anything. Think of it this way, say you had a 302hp 302ci motor. Thats 1hp/cube. You now have 306ci, so u now have 306hp for a total of 4more hp. Your not even going to feel that. i suggest if your car is completly stock you get some exhasut and gears.
 

5spd GT

"the 5.0 owns all"
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Sep 19, 2004
#3
  • Sep 19, 2004
  • #3
Well from a worn-out 302 (assuming you would rebuild the rest of the bottom end)...to a fresh 306 it would be noticeable and would be a nice thing to do for the longevity of the engine...

But fresh 302 vs. fresh 306...a few horspower maybe...
 

PhLoBuS

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Sep 19, 2004
#4
  • Sep 19, 2004
  • #4
not worth the time and money is how I see it unless your engine is going...
 
D

dkhl

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#5
  • Sep 19, 2004
  • #5
No, the engines in the shop still.. it's already been bored to 306, but i did a whole bunch of other things with it.. I was just wondering for curiosities sake what would happen if i just bored it stock.
 

5spd GT

"the 5.0 owns all"
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#6
  • Sep 19, 2004
  • #6
dkhl said:
No, the engines in the shop still.. it's already been bored to 306, but i did a whole bunch of other things with it.. I was just wondering for curiosities sake what would happen if i just bored it stock.
Click to expand...

You did the right thing...that 306 gives it a "new" cylinder wall...for the pistons and rings to "sit" in...
 

green

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Apr 26, 2003
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Sep 19, 2004
#7
  • Sep 19, 2004
  • #7
yep, it wont give u much more power but it will give u new cylinder walls
 

04sleeper

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Jun 22, 2002
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Sep 19, 2004
#8
  • Sep 19, 2004
  • #8
Thats why most replacement blocks are 306's. They bore them to get a True cylinder. Not for HP reasons.
 

N8Miller

I need NOS....make it 2 of the big ones
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Sep 19, 2004
#9
  • Sep 19, 2004
  • #9
5spd GT said:
But fresh 302 vs. fresh 306...a few horspower maybe...
Click to expand...

i hear its like 4-5hp. like said before, do it if your engine is in need of rebuilding.
 

5.0Droptop

...all those nights we shared, and you're a dude??
Special Agent Mukity-Muck Whats in Charge Round Here
May 15, 2002
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Indiana
Sep 19, 2004
#10
  • Sep 19, 2004
  • #10
made a huge diff on my car..






but then i went to afr 165 heads tfs1 cam and other goodies too...
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
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Sep 19, 2004
#11
  • Sep 19, 2004
  • #11
Going 306 you have to use different pistons, that can have an effect.

Like said before fresh 302 vs. fresh 306, hardly anything. I have heard that .030 overbore will help unshrowd the valves a little more.

Like said before worn 302 vs. fresh 306, big difference. I think some people overlook the actuall engine. Spend all this money on a nice set of heads, an a good cam, slap it on an worn out engine and wonder why they are getting beat.

Also, a worn stock 302 vs. a fresh 306 with higher comp pistons, balanced, good rings, world of difference.
 
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