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How hard is it to make 400 rwhp on n/a 331 or 347?

  • Thread starter Thread starter Cardinal Sin89
  • Start date Start date Dec 8, 2009
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Cardinal Sin89

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Hey guys this is my first post just getting back into the mustang thing, bought a bolt on 89GT [gears,exhaust]. I plan on buying a topend kit from Anderson motosports for the stock block this winter, and hoping to hit 300rwhp. That should hold me over for a couple of years. But will eventually do DSS 331 or 347 stroker and would like to swap the top end over, would that get me close to 400 or would I have to do a whole new top end again. Thanks for any help?
 

5.0Torx

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Dec 30, 2007
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#2
  • Dec 8, 2009
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400 is definitely possible. The power peak will just be at a higher rpm than a 300 rwhp build. Whether or not thats what you want is up to you.
 

1991notchbackLX

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#3
  • Dec 8, 2009
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build a 351 based motor for the same price as a 302 based one, make more power more safely and have more peace of mind... throw a power adder at it if you get bored with n/a and also still be confident that it will stay together

/thread
 

5.0Torx

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#4
  • Dec 9, 2009
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lol...says the traitor with the 4.6s!
 

srtthis

the guy doing it does every local racers rear end
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#5
  • Dec 9, 2009
  • #5
400 hp NA is very doable... but the traitor is right... going 351 based for the same price punched out to a 408-410 will make more power safer

1991notchbackLX said:
'03 Cobra motor 17k miles, 3" Amazon pulley and tune, Art Carr C4 with 4000 stall and trans brake, solid axle with 31 spline and 3:73s, Mach 1 brakes, QA1 tubular K, Eibach drag springs, lakewood 90/10 and 50/50, A/C delete, manual rack, SFCs, LFP dual bypass heat exchanger, MAC prochamber and catback, AEM wideband, Autometer gauges, etc. D
Click to expand...


100% off topic...

thats basicly the same cobra as that red cobra i posted the video of... but it had ac still and power steering. stock front end with GT springs... abut had a 2.2KB
 

blackened88lx

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Dec 9, 2009
#6
  • Dec 9, 2009
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1991notchbackLX said:
build a 351 based motor for the same price as a 302 based one, make more power more safely and have more peace of mind... throw a power adder at it if you get bored with n/a and also still be confident that it will stay together

/thread
Click to expand...

Unless you're dead set on keeping it 302 base, which some people are, this is the best way to go. But if you really want 331 or 347 400+rwhp is pretty easily doable, even at a reasonable rpm range.
 

srtthis

the guy doing it does every local racers rear end
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#7
  • Dec 9, 2009
  • #7
blackened88lx said:
Unless you're dead set on keeping it 302 base, which some people are, this is the best way to go. But if you really want 331 or 347 400+rwhp is pretty easily doable, even at a reasonable rpm range.
Click to expand...

to add to that... when was the last time some one said i only want 400hp... then 3 months later they want 500... then 600 then 700.... you get the point...

with a stock 302 block your going to have to build ANOTHER motor at that point. with the 351 based stuff you can expand a good bit...
 
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Cardinal Sin89

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#8
  • Dec 9, 2009
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Thanks for the help guys, my question with going 351 is, will the top end kit it get for the 302 be able to fit on the 351, Also would just swapping the top end over, get me 400 rwhp. I really dont want to buy parts twice. Thanks for the help.
 

srtthis

the guy doing it does every local racers rear end
15 Year Member
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www.crazybobracing.com
Dec 9, 2009
#9
  • Dec 9, 2009
  • #9
Cardinal Sin89 said:
Thanks for the help guys, my question with going 351 is, will the top end kit it get for the 302 be able to fit on the 351, Also would just swapping the top end over, get me 400 rwhp. I really dont want to buy parts twice. Thanks for the help.
Click to expand...

pretty sure as long as the heads are set up for a 1/2" head bolt they will go on... then the intake would be different. id go with one that could be set up with both a 302 and 351 with a lower swap
 

90lxcoupe

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#10
  • Dec 9, 2009
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Chances are if your putting a top end kit from a 302 onto any bigger motor it will not make your goals.

You'd be supriesed how cheap you can build a 357w, if i was in your shoes i'd save some money and buy cyl heads, cam, and intake once
 
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92GreenGT

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#11
  • Dec 9, 2009
  • #11
90lxcoupe said:
You'd be supriesed how cheap you can build a 357w, if i was in your shoes i'd save some money and buy cyl heads, cam, and intake once
Click to expand...

Agreed.

Take the money you were going to spend on the top end kit and go ahead and buy the 351 and get the bottom end together and ready. Or start sizing bigger stuff than you're planning and go ahead and order the top end for the bigger engine, don't put "small" stuff on a big cube engine.
 

90lxcoupe

20+ Year Stangneter
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#12
  • Dec 9, 2009
  • #12
Its all about having a plan, with realistic end goals and sticking to your plan
 

1991notchbackLX

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#13
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Haha, I guess I can accept being the traitor that everyone agrees with.
 

fiveohwblow

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#14
  • Dec 9, 2009
  • #14
 

90lxcoupe

20+ Year Stangneter
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#15
  • Dec 9, 2009
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1991notchbackLX said:
Haha, I guess I can accept being the traitor that everyone agrees with.
Click to expand...

I wouldnt call you a traitor if you took an 86 GT converted it to an aero, and it had a LS motor in it

But if you had a stock 5.0 with euro lights you would be a big h-mo
 

fiveohwblow

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#16
  • Dec 9, 2009
  • #16
90lxcoupe said:
I wouldnt call you a traitor if you took an 86 GT converted it to an aero, and it had a LS motor in it
Click to expand...

 

1991notchbackLX

Active Member
Dec 25, 2007
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#17
  • Dec 9, 2009
  • #17
90lxcoupe said:
I wouldnt call you a traitor if you took an 86 GT converted it to an aero, and it had a LS motor in it

But if you had a stock 5.0 with euro lights you would be a big h-mo
Click to expand...

Haha, agreed.

Hmm, what if i Whippled this cobra motor and slammed the whole drivetrain into a gutted 4 eye notch and broke into the 9s. I wonder if I'd be a traitor then...
 

fiveohwblow

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  • Dec 9, 2009
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Negative. Instant hero status.
 

srtthis

the guy doing it does every local racers rear end
15 Year Member
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Dec 9, 2009
#19
  • Dec 9, 2009
  • #19
1991notchbackLX said:
Haha, agreed.

Hmm, what if i Whippled this cobra motor and slammed the whole drivetrain into a gutted 4 eye notch and broke into the 9s. I wonder if I'd be a traitor then...
Click to expand...


9's? i bet it could go 8's...

jrsblownsnake on SVTP went 8.76 (think it was a 76 he doesnt post anymore since he sold the car but it was 8's) with a 302 mod motor with a 3.4 whipple and a C4... a stock motored whippled cobra with a c4 in a light ass coupe should FLY!
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
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#20
  • Dec 10, 2009
  • #20
Posted via Mobile Device i've got 35hp to go so come spring i'm looking into a single plane intake and custom carb. I think that should just about get me there. Price just depends on how resourceful you are. I got my long block with the cam for 1350 used. If you do your homework and catch some deals on the classifieds you can do it fairly cheap.
 
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