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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

04 GT Engine swap to 03-04 Cobra

  • Thread starter Thread starter 04YELLOWGT
  • Start date Start date Oct 18, 2005

04YELLOWGT

Active Member
Jun 29, 2005
1,135
2
39
Indiana
Oct 18, 2005
#1
  • Oct 18, 2005
  • #1
Hitten the big times. lol

Ive looked at SC and NOS. SC my car would be about $5500 total but that would be on stock internals and still not close to a Cobras power or potintial. So I finaly decide to just by a Cobra Crate Engine for 10K or less in about a year or less.

SO now is ? time.

First: I have an Automatic and plan on keeping it. Can I use the stock transmission or not?

Second: Can I reprogram my ECU or should I just buy a new chip?

Third: Do I need to buy a Cobra Fuel tank or can I keep the one I have.

Fourth: New exhaust will have to be bought too right?

Fith and final: How much do you think I can get out of my engine? Its stock and will have prolly less than 20,000 miles on it when sold.

Thanks for your help.
 

TrueCustoms

New Member
Aug 25, 2005
57
0
0
Oct 18, 2005
#2
  • Oct 18, 2005
  • #2
Well from my experiences being interested in that swap...

-I wouldnt do anything short of a T-56 with the 03 motor.
-You can have your ecu reflashed with a cobra program, you just wont have the anti-knock thing, but its worthless anyway.
-You will need some fort of fuel system upgrade... whether it be the 03 dual pump setup, or a focus pump and boost-a-pump, you have to feed that engine the proper amount of fuel.
-You wont need new exhaust unless you swap in the IRS system, you will still be going over the axle.
-I would assume you could get 12-1500 for a stock gt engine, depends on how you well it and if anyone wants to buy it, you know.

All in all the swap will cost much more than just the engine. Engine and t-56's are going for ~12k, then you will need a new fuel system ~750-100, dyno tune, radiator, underhood plumbing, all that good stuff. Plan on spending some more than you expect.

This is why Im planning on a continuing buildup of my 2v... going stroked and blown... just how i like it.
 

LS2 KLR

Member
Apr 16, 2003
452
0
17
Houston, TX
Oct 18, 2005
#3
  • Oct 18, 2005
  • #3
Honestly you're better off with a 2v. It will run you $12-$15k for the cobra swap. When modded you are looking at most 600rwhp. You could spend alittle less with a blown 2v and make 550-650rwhp but be more reliable.
 

TrueCustoms

New Member
Aug 25, 2005
57
0
0
Oct 18, 2005
#4
  • Oct 18, 2005
  • #4
And that is 15k for just the stock 390hp... modded as in pully, ported eaton, intake, headers, full exhaust, new clutch, new differential, new axles, and trans cooling mod... its somewhere around 22k... believe me, i've added it up, haha. And that puts you around 500-550hp on 93 octane and a good tune. Put that money into some forged internals (stroker if you wish from vt,mph,etc) and a nice blower... KB or Novi 200, and a new clutch for starters and put out, say 450 safe and then spend some more on the rearend and a t-56 and whup on some stock and pullied 03's. Then replenish your funds and crank up the boost. GT badges blowing off Cobra badges is a beautiful and wonderful suprise.
 

04YELLOWGT

Active Member
Jun 29, 2005
1,135
2
39
Indiana
Oct 18, 2005
#5
  • Oct 18, 2005
  • #5
So what would you reccomend me buying for the internals
 

TrueCustoms

New Member
Aug 25, 2005
57
0
0
Oct 18, 2005
#6
  • Oct 18, 2005
  • #6
I believe my plans are with Modular Powerhouse for a buildup (will probably buy a stroker shortblock). www.vtengines.com www.modularpowerhouse.com www.dssracing.com All have great stock stroke and 302 stroked internal kits at around the same price, VT being the most expensive, but you get what you pay for.
 
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