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Cobra 4.6 SVT engine questions - supercharger assistance needed.

2K views 8 replies 2 participants last post by  eschaider 
#1 · (Edited by Moderator)
Hi all,

Im a hot rodder from New Zealand and I have a 32 valve Teksid block 4.6 SVT engine.

The previous owner was going to fit it into a kit car (an AC Cobra replica) but we had some nasty earthquakes in February 2011, and unfortunately he was one of the 185 who were killed. I bought the engine because it was available and Id never had one of them, but not really because I had any need of it.

New Zealand never got any car new from Ford with the 4.6 32 valve engine, so there arent many around. We did get a 5.4 Navigator style engine which came with the 32 valve heads in the Australian Falcon XR8, but they were on an iron block.

I purchased a 27 T roadster and decided to remove the 307 Chev and fit the 4.6, but then came across a 5.4 XR8 engine & box and I had that fitted instead.

Recently, I purchased an Eaton M122 which was advertised as being from a GT 500, which I assume is the Shelby. It did not come with an intake.

So here are my questions:
  1. What intake will I need to fit the Eaton onto my 4.6?
  2. Who sells them in the USA? (Theres very little chance that there will be any in this country, and close to no chance that there will be one for sale)

I can buy low comp forged pistons and decent rods out of Australia for around NZ$2000, and I also have a NOS B&M 420 megablower thats never seen fuel in its life. We took the lower half of the Cobra intake and I had a flat plate machined to fit onto it and take the B&M blower. After doing that I figured that Ford spent a fortune sorting out a blown motor for the Mustangs, so there wasnt really much point in trying to be different for the sake of it. So thats when I bought the Eaton M122.

So can you guys (and ladies) give me some advice on the best options for my 4.6 engine.

THanks in advance.

Cheers
Todd
 

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#3 · (Edited)
Don't worry Todd, I cleaned it up for you.

On to your questions.

Hi all,

Im a hot rodder from New Zealand and I have a 32 valve Teksid block 4.6 SVT engine.

The previous owner was going to fit it into a kit car (an AC Cobra replica) but we had some nasty earthquakes in February 2011, and unfortunately he was one of the 185 who were killed. I bought the engine because it was available and Id never had one of them, but not really because I had any need of it.

New Zealand never got any car new from Ford with the 4.6 32 valve engine, so there arent many around. We did get a 5.4 Navigator style engine which came with the 32 valve heads in the Australian Falcon XR8, but they were on an iron block.

I purchased a 27 T roadster and decided to remove the 307 Chev and fit the 4.6, but then came across a 5.4 XR8 engine & box and I had that fitted instead.

Recently, I purchased an Eaton M122 which was advertised as being from a GT 500, which I assume is the Shelby. It did not come with an intake.

So here are my questions:
  1. What intake will I need to fit the Eaton onto my 4.6?
  2. Who sells them in the USA? (Theres very little chance that there will be any in this country, and close to no chance that there will be one for sale)
You will need a lower intake for a 03/04 Supercharged 4.6L engine. They are becoming much harder to locate but they are still available if you are patient and search for them. Good places to look are the various Mustang forums and eBay. I just did a search of eBay and turned up this one, click here => Cobra Blower Manifold.
the price they are asking is a fair price. If you are serious about this type of engine this is a no longer available part I would go after with a vengeance.

In addition to the lower manifold you will need to find an intercooler core or buy a new aftermarket one from Kenne Bell or an other provider. You will find the Mustang websites, Facebook and eBay to be your friend again. This is an intercooler I found on eBay click here => Intercooler The eBay pricing is again a fair price and these like the intake manifold are no longer available from Ford, so just like the intake manifold lower I would jump on this.

In addition to the above two critical pieces you need the Intercooler coolant inlet casting. eBay again, click here => Intercooler Coolant Inlet
that price is high and although Ford does not sell these anymore, if you have access to a CNC machining service you can easily create one from billet.

You still need the adapter plate to mount a M122 on the Cobra lower. There is only one I know of that just flat works. It is made by Cobra Engineering, click here =>Cobra Engineering. You will end up needing / using just about every component on that page.

I can buy low comp forged pistons and decent rods out of Australia for around NZ$2000, and I also have a NOS B&M 420 megablower thats never seen fuel in its life. We took the lower half of the Cobra intake and I had a flat plate machined to fit onto it and take the B&M blower. After doing that I figured that Ford spent a fortune sorting out a blown motor for the Mustangs, so there wasnt really much point in trying to be different for the sake of it. So thats when I bought the Eaton M122.

So can you guys (and ladies) give me some advice on the best options for my 4.6 engine.

THanks in advance.

Cheers
Todd
Before you buy pistons take the time to read this post about custom pistons. Pay particular attention to how heavy the skirts are. Thin n/a skirt designs collapse under the cylinder pressures a blown 4.6L engine is capable of. Click here for the thread, Off the Shelf Custom ModMotorPistons

With respect to the old B&M blower, you should sell that to finance the other pieces you will need. It is a very inefficient blower design. The Eaton TVS design offers much better compressor performance and engine power. The adapter plate is a non-trivial component to manufacture. If you intend to use the M122 I would strongly encourage you to use the Cobra Engineering solution - it just works.

If you decide to use a KB or Whipple Twin Screw or a VMP TVS they come with the proper lower adapter plate to bolt right up to the OEM lower intake manifold above.

You haven't spoken to the EFI system yet. The OEM computer has had a wide variety of hard stops we have had to work around / with over the years since the engine was intriduced. This last month DIYAutoTune <= clickable, introduced a Plug and Play fully programmable race quality ECU for the engine. It is a poor man's Haltech or Motec equivalent but it only has a $1349 price tag and uses the OEM wiring harness and all the OEM sensors! Check it out you will be surprised.

You still need to do a fuel system and the place to go for those pieces is Fore Innovations <= clickable. Everything you need is on that page.

This should cover about 90 to 95% of everything you will need to do the engine. I left out the Terminator specific timing cover and pulley bridge wihich is unique to the engine and like everything else is going to be challenging to find but, is out there. Same search locations Mustang sites, Facebook, eBay. It will take a bit of time but it will all come together if you persevere.

Ed

p.s. Be careful when you are done with your build. That engine in a light weight car like you are putting it into, is literally lightening in a bottle! It will produce 600 or more horsepower but there is no ramp up in power with a positive displacement blower. When you hit the throttle it is literally all there, all the time, from a dead idle - so be careful. It will jump up and bite you so fast, at any vehicle speed, that you can not possibly imagine - even at 100 km/hr or faster!
 
#6 · (Edited)
Thanks for that Ed.

My last street legal T bucket ran a 671 blown 540 BBC and ran into the 9s on the quarter. It made 851 hp but it also ran into the wall at the dragstrip so I know how quickly things go pear shaped.
That's sort of the kind of mischief I was referring to. Although it sounds crazy you want to cut a fairly wide safety path for a Terminator engine in you hot rod. My guess is the car in your picture weighs in at around 2500 lbs (~1130 kg). An 03/04 SVT Cobra w/o a driver will weigh in around 3500 lbs (~1590 kg) or more. A properly built and tuned 03/04 Terminator engine with a 190 lb (~85 kg) driver will run 8.90 second quarter miles at over 160 mph. As a general rule of thumb we use a performance metric that says every 100lbs (~45 kg) is worth 0.1 seconds of elapsed time. That means a 1000 lb difference in car weight will reduce your elapsed time by a full second. That 8.90 second fully bodied 03 Cobra suddenly became a 7.90 second open wheel roadster. I guarantee you the first pass will put the fear of God into your soul.

Do not be deceived by the diminutive displacement of the Terminator engine. The supercharger completely changes the game. The engine is simply a giant killer and you do not want to underestimate it's potential for mischief in a 2500 lb car - especially in street trim and on the street. Traction will be all but non existent which is begging for some type of traction control. The easiest, cleanest way to do this is part and parcel of the software features in the NS3Pro PnP ECU from DIYAutoTUNE. I can't encourage you strongly enough to embrace that ECU for your build.

The torque and horsepower these engines produce is unlike any street driven and most track driven engines that have preceded it - especially with a Whipple or KB Twin Screw or one of the VMP TVS blower alternatives. That makes any car, especially a light car, extraordinarily unpredictable and dangerous on the street. These engines in light cars really are lightening in a bottle.

Ed
 
#7 ·
It is Todd but it is over twice as expensive as the eBay alternative I linked you to. Even with shipping and whatever import duty you might be assessed it could turn out to be cheaper to buy off eBay.

Ed
 
#8 ·
US$375 is just under NZ$600 (The US$ is strong and the NZ$ is weak)

Throw in NZ$100 to freight it here and it arrives at just under NZ$700 and the NZ Govt wants 15% of the landed price, so thats another NZ$100 and the price is about the same at NZ$800.

And thats why it costs a fortune to play with hot rods down here. An NZ dollar buys about US 63 cents so anything that costs you guys US$100, we have to stump up with over NZ$150 and then get it back here. And our wages tend to be way lower than yours too.

A new 5.0 Mustang coupe (in RHD from Ford) is drive of the lot at NZ$81,000 and the convertible is at NZ$86,000 - so thats US$54000 on the convertible
 
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