5.4 with mach 1 heads swap

[dannyboy1999]

I have a 5.4 cast iron with mach 1 heads what kind of exhaust manifolds or headers will fit ?fyi its going in a 02 mustang gt

 

[07GtS197]

Any 4v shorty header for a 96-04 cobra or mach 1 will fit but the midpipe will need to be widened and may need to be lengthened.

 

[dannyboy1999]

Any 4v shorty header for a 96-04 cobra or mach 1 will fit but the midpipe will need to be widened and may need to be lengthened.

Damn so no lontubes huh ?

 

[07GtS197]

Damn so no lontubes huh ?

Unless you can fab a set, no. I’ve seen it done on a 5.4 2v but it was all custom.

 

[dannyboy1999]

What kind of compression ratio and i looking at with these heads ?

 

[07GtS197]

I’m not sure but our resident 5.4 expert @96blak54 may be able to answer that.

 

[dannyboy1999]

I’m not sure but our resident 5.4 expert @96blak54 may be able t

I’m not sure but our resident 5.4 expert @96blak54 may be able to answer that.

Fursure thanks . I also recently fully rebuilt my 4r70w with a shift kit in it would the bell house fit ?

 

[dannyboy1999]

Fursure thanks . I also recently fully rebuilt my 4r70w with a shift kit in it would the bell house fit ?

Also any pointers on the the ecu ? Im thinking of buying a mega squirt to really be able to tune everything but is it really gonna be worth it or should i spend money elsewhere on parts and just keep my 2v ecu and tune it ?

 

[07GtS197]

Fursure thanks . I also recently fully rebuilt my 4r70w with a shift kit in it would the bell house fit ?

Yes all Modular’s have the same bellhousing bolt patterns.

Also any pointers on the the ecu ? Im thinking of buying a mega squirt to really be able to tune everything but is it really gonna be worth it or should i spend money elsewhere on parts and just keep my 2v ecu and tune it ?

The stock ecu will work with some tuning. The stock gt tune will work fine with a 4v but the extra displacement might need some more tuning.

 

[96blak54]

An aftermarket k-member will serve you good with headers installed on any modular engine. Headers are a royal pain, especially with the stock kmember. The aftermarket kmember allows more accessible room

 

[dannyboy1999]

An aftermarket k-member will serve you good with headers installed on any modular engine. Headers are a royal pain, especially with the stock kmember. The aftermarket kmember allows more accessible room

You think its worth the money though ? Kmember 300-600$ plus long tubes the cheapest i found were 400$ so for the extra 10 to 20 hp would it be worth it ?

 

[TTSaleen]

Don't even attempt headers in your combo without an aftermarket k-member.
And don't bother with shorty headers compared to long tubes. Shorty headers are a waste of money over stock manifolds compared to long tubes.
Beware of cheap headers, they don't always fit properly and may require some heavy massaging to fit.
BBK for lower end cost fit OK and Kooks for a higher end cost fit better.

As mentioned, your stock ECU is just fine.
Simply have it tuned and you'll be good to go.

The 5.4 is wider and taller than the 4.6.
Your intake manifold choice will dictate what hood you can run.

Example - I have a 5.4 with 4 valve heads in my 98 Saleen.
Even with a 4inch cowl hood, I still had to install 1" spacer blocks between the k-member and the frame to allow the motor to drop enough to clear the hood using my Sullivan intake manifold.

Good luck.
Not alot of 5.4 conversions (especially with 4 valve heads) anymore.
Ryan

 

[Snorky]

You think its worth the money though ? Kmember 300-600$ plus long tubes the cheapest i found were 400$ so for the extra 10 to 20 hp would it be worth it ?

Buy used headers on market place. I seem to find a few sets of bassani mid lengths and matching x pipe for 4vs pop up.

 

[dannyboy1999]

Buy used headers on market place. I seem to find a few sets of bassani mid lengths and matching x pipe for 4vs pop up.

Not really worried much about my mid pipe cause my old setup up was straight piped anyway so ill most likely leave it striaght piped for the 5.4 aswell

 

[Snorky]

Not really worried much about my mid pipe cause my old setup up was straight piped anyway so ill most likely leave it striaght piped for the 5.4 aswell

Can always get some bassani mid or bbk long tubes and use a torch and a hammer to make the headers fit

 

[dannyboy1999]

Don't even attempt headers in your combo without an aftermarket k-member.
And don't bother with shorty headers compared to long tubes. Shorty headers are a waste of money over stock manifolds compared to long tubes.
Beware of cheap headers, they don't always fit properly and may require some heavy massaging to fit.
BBK for lower end cost fit OK and Kooks for a higher end cost fit better.

As mentioned, your stock ECU is just fine.
Simply have it tuned and you'll be good to go.

The 5.4 is wider and taller than the 4.6.
Your intake manifold choice will dictate what hood you can run.

Example - I have a 5.4 with 4 valve heads in my 98 Saleen.
Even with a 4inch cowl hood, I still had to install 1" spacer blocks between the k-member and the frame to allow the motor to drop enough to clear the hood using my Sullivan intake manifold.

Good luck.
Not alot of 5.4 conversions (especially with 4 valve heads) anymore.
Ryan

Gotcha also saw a aussie 290 intake for 750 was thinking of running to make up for the stock exhaust mainfold if i did stocks but i have heard that those intake mainfolds are limited editon to Australia and actually provide alot more power then the U.S Variants. And i 100% agree with the rarity of this swap. Ive only seen 2v or 3v swaps did my research on those as well what im not understanding much is exactly how is it that the 2v 5.4 is rated 330-350lbs torque & 3v 5.4 are rated 330-360 but our 4v is 330 solid

 

[Snorky]

Gotcha also saw a aussie 290 intake for 750 was thinking of running to make up for the stock exhaust mainfold if i did stocks but i have heard that those intake mainfolds are limited editon to Australia and actually provide alot more power then the U.S Variants. And i 100% agree with the rarity of this swap. Ive only seen 2v or 3v swaps did my research on those as well what im not understanding much is exactly how is it that the 2v 5.4 is rated 330-350lbs torque & 3v 5.4 are rated 330-360 but our 4v is 330 solid

The 2v heads produce a lot of low and mid range but they lack up top.the 4v heads have great flow so they make mid to upper range hp. Trust me. You will have plenty of tq like the 2v but more hp

 

[dannyboy1999]

The 2v heads produce a lot of low and mid range but they lack up top.the 4v heads have great flow so they make mid to upper range hp. Trust me. You will have plenty of tq like the 2v but more hp

How much are producing whp?

 

[96blak54]

If you build relative stock with moderate upgrades youll be in the 330-350 whp range.

My suggestion, if using stock cams, retard the stock exhaust cam 1 tooth from normal location . This will change the exhaust opening(IIRC) 16degree later and give you 16degree more overlap after top dead center. This will bring torque and hp up. If using off the shelf aftermarket cams, youll still want to get the exhaust to open much later with the aftermarket cams. Do this by having the cam company regrind the exhaust opening event later. In other words when you purchase cams, you buy the valve events that you want and the typical "special grinding" 97percent of the time is remapping the exhaust opening to a delayed event. Any cam company that grinds will do this. Dont spend the extra $200 to get so and so special grinds.
This will get you a good 30-40whp. Keep in mind that if you do degree the stock cam exhaust 1 tooth, youll need to be 100percent sure the intake cam is in normal location. If you decide to degree all the cams precisely, it typically means removing the sprocket keys and using the bolt to drive the cams or purchasing degreeable cam sprockets.

Can a 5.4l 4v achieve N/A 450whp, absolutely. Alot of key build attributes must be made, like zero deck pistons, cams, and the intakes you mentioned. As for headers, its really about how much power you want to squeeze out of a naturally aspirated engine and they typically only open up 20rwhp at the most. Which is alot if you think about it for a naturally aspirated engine, but even forced induced engines its rough 20whp.

 

[dannyboy1999]

Okay im slowley getting the hang of thise swap. Like it was said these 5.4 4v are rare on youtube so i dont really have all the info but as far as the wiring harness since im useing mach 1 manifolds with will i still have to swap polaritys for the coils ?