4.6 sohc swap to dohc

[GT40Mustang]

what has to be done to make a 4.6 sohc a dohc? anyone done the swap

 

[teknik]

Pretty much all you need is a motor. Some of the wiring and ECU would be nice, but I know some people who have done it using the GT ECU. You just have to make sure you have a very good tuner. Even then they may tell you they would prefer the DOHC ECU. It really isn't all that complicated, just don't try to replace heads and intake only and keep your bottom end. It isn't worth the cost or labor at that point.

 

[Race_Red_5Oh]

^ he's so educated and smart, wish i knew that stuff

 

[teknik]

^ he's so educated and smart, wish i knew that stuff

Hey Thanks.......trust me though, it takes quite a few screw-ups to learn your lessons on how to do things right.

 

[EHA Racing]

I just happen to have an engine harness for a DOHC Mach 1 engine. I know the polarities on the coils are different and I think you can use a stock GT ECU if you change the polatrities of the coil at the plug. What would be even easier is to buy the MSD Mod 6 controller and harness for a F/I setup. That way you can adjust the timing map with your lap top. I have acces to s stock timing map that you could upload into the controller for a base tune. Hope that helps.
(Oh) I have a whole Mach 1 shaker system too if your looking!! LOL

 

[TBapp3]

and how much does a dohc engine cost???? Just out of curiosity???

 

[EHA Racing]

and how much does a dohc engine cost???? Just out of curiosity???

I just bought one out of a wrecked '03 Mach for $2,900. Has 16K on it and came 100% complete.

 

[TBapp3]

Wow not bad at all!! Puts out a good 60-70RWHP more than the sohc right???

 

[EHA Racing]

Wow not bad at all!! Puts out a good 60-70RWHP more than the sohc right???

I think it's 305hp as is. I'm throwing a sullivan intake and a pro-systems custom carb on it. Should make another 25 - 30 horse that way.

Another note, if you purchase a Mach 1 engine get one that has a 5 speed behind it. The manual cars came wit an 8 bolt cobra crank and the auto came with a cast steel. You can get an auto flexplate for an 8 bolt if you want to convert.

 

[TBapp3]

Thats Sweet...sounds like you got a good deal!!!

 

[EHA Racing]

Thats Sweet...sounds like you got a good deal!!!

Oh yeah, I really don't need all that power because it's going in a 1,200lb '23 T-Bucket haha.

 

[TBapp3]

^^Awesome!!!

 

[roush360r]

well to build a dohc would be quite a bit more. you need twice as many cams, unless you use the factory cams but if you plan on building a motor you might as well go right through the motor. itd be alot easier just to use a dohc pcm. just do all the motor work youd ever want to do before it goes in cause theres no room once its in.but thatd be a mean t bucket if you put a blower on it. everyone needs a little boost

 

[97modgt]

I just bought one out of a wrecked '03 Mach for $2,900. Has 16K on it and came 100% complete.

The 03-04 machs did not come fully forged like the Cobra's during thoughs years did they? Maybe they did i just never knew.

 

[EHA Racing]

The 03-04 machs did not come fully forged like the Cobra's during thoughs years did they? Maybe they did i just never knew.

The Mach's with manual trannies came with the 8 bolt cobra crank. The auto's came with a cast crank. I got on from a 5 speed car.