[alarsen1325]

I'm hoping to pick the brains of some of you modular 2v gurus. I know some of you have a ton of knowledge about these engines.

My situation: I bought a 1997 stang a year or so ago. The guy I bought it from talked a lot about the performance upgrades on the car and said it had a complete "svo" (aka Ford Racing) package installed. I wasn't too clued in as to what all of the meant but for a beautiful GT complete with side exhaust, body kit, 18" wheels, and under 60K miles, I thought what the heck so I bought it.

Further investigation revealed that indeed Ford Racing did put out an alternate set of heads commonly referred to as SVO which flowed much better than the stock heads. To compliment the heads, they also put out a matching intake (looks quite similar to the Bullitt intake but port matched to NPI heads) and an alternate ECM unit. After looking deeper into what was on my car, I found it had a doorman NPI intake with an aluminum crossover and standard NPI heads, but it does have the computer that was intended to go with the Ford Racing heads and intake. My guess is the car at one point probably had the full setup but pieces were swapped out before I bought it. Can't think of any other reason for the car having the alternate ECM.

My Questions: I'd really like to add some performance to my car but I'm not sure I want to spend in excess of $2K for the actual Ford Racing parts given the car is 15 years old. I already have a PI intake, coolant crossover, etc. and I'd like to match it with a set of PI heads both to help the engine breather better and to up the compression. I'm already running 93 octane since the ECM in the car has advanced the ignition timing.

First question, I'm looking around and it seems much easier to find PI head off an F150 or Crown Victoria. I know these all went PI in different years so I'm comfortable with that, but my question is is there any difference between these PI heads and a mustang? (btw-I want to stay Romeo so I'll make sure they have 11 valve cover bolts) Also is there any difference between the stock pi cams?

Second question, what are your thoughts on keeping the alternate Ford Racing PCM with this setup? I've heard you should get a tune when upgrading with the standard 96-98 PCM.

Final question, what should I look for in a set of used heads? Do I need to deck (resurface) the heads even if they don't have visible blemishes on the mating surface?

Thanks so much for all of your help guys!

[deedub97GT]

Originally Posted by alarsen1325 I'm hoping to pick the brains of some of you modular 2v gurus. I know some of you have a ton of knowledge about these engines. My situation: I bought a 1997 stang a year or so ago. The guy I bought it from talked a lot about the performance upgrades on the car and said it had a complete "svo" (aka Ford Racing) package installed. I wasn't too clued in as to what all of the meant but for a beautiful GT complete with side exhaust, body kit, 18" wheels, and under 60K miles, I thought what the heck so I bought it. Further investigation revealed that indeed Ford Racing did put out an alternate set of heads commonly referred to as SVO which flowed much better than the stock heads. To compliment the heads, they also put out a matching intake (looks quite similar to the Bullitt intake but port matched to NPI heads) and an alternate ECM unit. After looking deeper into what was on my car, I found it had a doorman NPI intake with an aluminum crossover and standard NPI heads, but it does have the computer that was intended to go with the Ford Racing heads and intake. My guess is the car at one point probably had the full setup but pieces were swapped out before I bought it. Can't think of any other reason for the car having the alternate ECM. sounds to me like you have been had. i think the aftermarked heads were just that. aftermarket not added from the factory. and if i remember right a few select cars came with different ecu's from different suppliers during the 96-97 years and i a doorman intake manifold is the kind that autozone sells that replaces the stock plastic crossover NPI. my guess is the guy took it in for the warranty work on it since there was a warranty on the stock manifold. side exhaust and 18" wheels also sounds like it was added after the fact. My Questions: I'd really like to add some performance to my car but I'm not sure I want to spend in excess of $2K for the actual Ford Racing parts given the car is 15 years old. I already have a PI intake, coolant crossover, etc. and I'd like to match it with a set of PI heads both to help the engine breather better and to up the compression. I'm already running 93 octane since the ECM in the car has advanced the ignition timing. First question, I'm looking around and it seems much easier to find PI head off an F150 or Crown Victoria. I know these all went PI in different years so I'm comfortable with that, but my question is is there any difference between these PI heads and a mustang? (btw-I want to stay Romeo so I'll make sure they have 11 valve cover bolts) Also is there any difference between the stock pi cams? pi heads off of f-150 and crown vics are all the same. the one thing you want to look for it this notice the pi emblem. that is on both heads. they are noticably bigger and the inlet where you add oil is on the passanger side instead of drivers. there is a difference in stock cams and pi cams. pi cams have the same lift but much different lobe. and on the stock pi bottom end with flat top pistons you dont want more lift. you will get PTV happened to me personally runninf a 232/232 duration on .5 inches of lift at the stock timing. and one set of the cams has a press on cam gear and others have a press on cam gear. they both do the same thing and work fine with the swap. also, dont be scared of using windsor heads you can generaly find them a lot cheaper. and the only difference in actually putting them on is two bolts from the timing cover. easy day. i used windsors on my motor before i built it to what it is now and they were great. i have them if your interested in purchasing just pm me about that. any other questions man ide be glad to help. Second question, what are your thoughts on keeping the alternate Ford Racing PCM with this setup? I've heard you should get a tune when upgrading with the standard 96-98 PCM. i think you have the rarer of the two ecu's if you get an sct tuner they have everything you need to use that scu. Final question, what should I look for in a set of used heads? Do I need to deck (resurface) the heads even if they don't have visible blemishes on the mating surface? i answered this one in my big paragraph lol Thanks so much for all of your help guys!

i put my advice in red welcome to the forums man!

[alarsen1325]

Thanks for your response. You're right, the svo parts would have been aftermarket from Ford Racing. I think the SVO heads are still available from Ford Racing but are called FRPP rather than SVO. The below link has more information about them.

4.6 liter Ford Engine Cylinder Heads

The intake was also aftermarket from Ford Racing. I've sometimes heard them referred to as a "Zeus" intake. More info at the link below:

4.6 liter Ford Engine Intake Manifolds

One for sale currently on ebay:

FORD MUSTANG 4.6L FORD RACING ZEUS INTAKE MANIFOLD ALUMINUM BULLITT STYLE | eBay

The computer was used to compliment these two parts. See a discussion about the computer at the link below:

tuning svo head combo | Mustang Forums at StangNet

I have verified that the ECM in my car is in fact the SVO version. I even hooked it up to a scanner could clearly see the ignition timing was well advanced compared to stock. And I agree, the Doorman intake obviously is an aftermarket version like those sold at Autozone so certainly didn't come with the car. My thoughts were that the former owner removed the heads and intake sometime prior to me purchasing the car.... guess I'll never know.

Thanks for your input on the heads. I guess I'd like to stay with Romeo mostly so I don't have to buy new valve covers. I have been able to find some locally off 01+ Crown Victorias, and even saw some yesterday off a 2005 F-150. I appreciate the picture of the head with the PI stamp, I'll be sure to look for it.

I didn't quite understand your note below regarding PTV. Are you saying I should not use the PI cams? Or rather just warning me about more aggressive cams that have more lift especially with NPI pistons that aren't dished as much as PI?

Thanks again for your help!

[deedub97GT]

just a warning about more lift i used pi heads with aftermarket cams with more lift and got ptv. the stock pi cams work just fine.

and if you interested pm me i got a set of windsor heads cams and valve covers for sale for $200 plus shipping. they also have comp cams behive springs that are rated up to .7 inches of lift at 250 lbs.

[97S281]

That ecu is the only svo part I don't have. You are right though, it was designed to work with the heads and intake combo but not the blower so more than likely the car had the combo at some point. The svo intake was manufactured by Zeus, that is why some people refer to them that way. If you actually turn a zeus intake over the ford part numbers are cast in the bottom of it. The zeus logo is more obvious on the top of the intake so some people don't realize it is the same thing.

Sorry you got screwed like that, It always sucks to hear about shit that.

I am sure a P.I. swap will make you more power than you are currently running though and it is alot easier to find than a svo setup. Though you do have a link to the intake and I have a set of heads for sale that need some machine work.

[alarsen1325]

Thanks for the replies guys. I agree it kinda sucks that the car doesn't have the svo parts on it, that would have been really cool. Given that I paid under $5K for it I'm still happy. The car had low miles, flawless leather interior, body kit, etc., which still made it a good purchase in my mind. I think the Borla side exhaust and side skirts are cool too. I loaded some pics in my garage if you want to have a look.

Thanks for the note on the heads DeeDub97GT. I'll send you a PM.

[Jhoward93]

Originally Posted by deedub97GT i put my advice in red welcome to the forums man!

Does every PI head have pi written inside?

[deedub97GT]

every one ive ever seen does

[Jhoward93]

Originally Posted by deedub97GT every one ive ever seen does

I have 2 sets both off a 2001 an neither one does.

[deedub97GT]

post a couple pics?