Cylinder Heads

Jul 13, 2017
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i have a 2004 GT. Since new heads are pretty pricey. Can the stock heads be ported and polished? If so, is it a waste of money? If not what mod would be the next logical step in building a street car? The car currently has cold air intake, x pipe and hi flow mufflers, and a tune. Any advise would be appreciated.
 
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Your next mod should be gears. 3.73 is the best ratio for a street car IMHO.

The stock heads can be ported and polished. Depending on who does the porting they can be made to flow almost as much as TFS heads. That will add a solid gain in power.

I think you should save up and get a base supercharger kit. It will cost you about what a head porting job would cost but make much more power.
 
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Your next mod should be gears. 3.73 is the best ratio for a street car IMHO.

The stock heads can be ported and polished. Depending on who does the porting they can be made to flow almost as much as TFS heads. That will add a solid gain in power.

I think you should save up and get a base supercharger kit. It will cost you about what a head porting job would cost but make much more power.
Your next mod should be gears. 3.73 is the best ratio for a street car IMHO.

The stock heads can be ported and polished. Depending on who does the porting they can be made to flow almost as much as TFS heads. That will add a solid gain in power.

I think you should save up and get a base supercharger kit. It will cost you about what a head porting job would cost but make much more power.
What supercharger do you suggest and where do you get a base kit? Most of the super chargers I seen cost $5000 and up.
 
LMR has the base Vortech kit for $3500 and the base intercooled Prochager kit for $3600. (Both prices using their 6% off coupon code)

If you figure on porting heads then you're talking $1200 just for the porting. Any changed parts would be extra. Might as well put new chains, guides, tensioners in while it's all off since they are a known issue. New gaskets and bolts. Labor to pull and install the heads. Dyno tune. You would quickly get to almost the same price as the kit.

Ported heads alone might get you 30-40 hp and a bit more torque with a tune. A supercharger would give you 100 hp easy and similar torque increase.
 
If I was doing the heads I would also upgrade the cams and possibly the TB which would definitely put you up in forced induction cost. IMHO adding a super charger is less work and less to go wrong during install than heads etc.I prefer the 3.73's also, especially on an auto trans, because it is not unusual for frwy speeds to be 75-80 mph during off times and the 3.73's work best for me..
 
And if doing cams because the heads are off might as well do headers too. Cams, ported heads, headers, probably a t-body and upper plenum...now you need to buy injectors as well. It adds up fast and still won't make the power a base supercharger would on a stock engine.

Save up and get the supercharger. The kits come with everything you need including injectors, fuel pump and the tune. Can install it in a day in your garage with hand tools. (Might have to get the fuel pump installed at a shop if it's too much to do in your garage on the floor) Then down the road, if the HP bug bites you again, you can dig into the engine. The difference will be that ported heads, cams and such will give much higher gains when a supercharger is there vs N/A. Although at that point you will need to build the bottom end to handle the power. The stock bottom end is on borrowed time once you hit 450-500hp at the crank.
 
And if doing cams because the heads are off might as well do headers too. Cams, ported heads, headers, probably a t-body and upper plenum...now you need to buy injectors as well. It adds up fast and still won't make the power a base supercharger would on a stock engine.

Save up and get the supercharger. The kits come with everything you need including injectors, fuel pump and the tune. Can install it in a day in your garage with hand tools. (Might have to get the fuel pump installed at a shop if it's too much to do in your garage on the floor) Then down the road, if the HP bug bites you again, you can dig into the engine. The difference will be that ported heads, cams and such will give much higher gains when a supercharger is there vs N/A. Although at that point you will need to build the bottom end to handle the power. The stock bottom end is on borrowed time once you hit 450-500hp at the crank.
 
LMR has the base Vortech kit for $3500 and the base intercooled Prochager kit for $3600. (Both prices using their 6% off coupon code)

If you figure on porting heads then you're talking $1200 just for the porting. Any changed parts would be extra. Might as well put new chains, guides, tensioners in while it's all off since they are a known issue. New gaskets and bolts. Labor to pull and install the heads. Dyno tune. You would quickly get to almost the same price as the kit.

Ported heads alone might get you 30-40 hp and a bit more torque with a tune. A supercharger would give you 100 hp easy and similar torque increase.
Sorry but I don’t see anything in that price range for an 04 GT.
 
https://lmr.com/item/VOR-4FA218150L/mustang-gt-vortech-supercharger-kit-satin-tuner-00-04-v-3

Vortech kit. Subtract the 6% online coupon...$3074. Add in injectors and FP with different online coupons and at about $3500. It's a tuner kit so this one would need a dyno tune although a dyno tune will make more power than a vortech box tune.
I really appreciate your help. I have always owned cars from the 70”s and feel I maybe over my head with this Mustang. It has only 4000 miles on it and seemed a good idea at the time to buy it. What size injectors would you recommend for this car? I only drive it once in a while on the weekends if I have the time. Can I still keep the mods on the car or do I need to take it back to stock? I know American Muscle has a supercharger where the car has to be stock.
 
A CAI wouldn't be used with the supercharger as it would come with its own but any other mods can stay and would be taken into account with a dyno tune.

The base vortech kit comes with 39 lb Lucas injectors so 39-42 lb injectors would be perfect for a basically stock engine. A SVT focus pump would be just fine for a FP or take your pick of several other performance FPs.

These cars are actually not bad to work on. If you can change spark plugs and oil you can install a vortech V3 kit.
 
Just so you know what you can expect....

I bought my 90k mi 04 GT auto a year ago. Came with a Vortech V3 and full aftermarket exhaust headers back. Was fast. I installed the CX racing A/A intercooler kit, changed to a 3.33" pulley, 75mm t-body and TFS upper plenum. Dyno tuned last fall at 370rwhp which the tuner said is about 500hp at the crank considering the auto with a slightly slipping converter. It's de-tuned to allow the engine to live till I can build a new engine for it. It's stupid fast IMHO and the engine itself hasn't been touched.

You will be very happy with just the base vortech kit. It will make you smile like a little kid.
 
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Just so you know what you can expect....

I bought my 90k mi 04 GT auto a year ago. Came with a Vortech V3 and full aftermarket exhaust headers back. Was fast. I installed the CX racing A/A intercooler kit, changed to a 3.33" pulley, 75mm t-body and TFS upper plenum. Dyno tuned last fall at 370rwhp which the tuner said is about 500hp at the crank considering the auto with a slightly slipping converter. It's de-tuned to allow the engine to live till I can build a new engine for it. It's stupid fast IMHO and the engine itself hasn't been touched.

You will be very happy with just the base vortech kit. It will make you smile like a little kid.
+1. Had the same experience. These cars love boost.

These cars are easy to work on. Find a reputable local tuner that is familiar with mustangs. Go ask them what tuner device they prefer and the best way to get your car to them. Take your time and read the install instructions. The install instructions are online: https://cdn.shopify.com/s/files/1/0...4_Ford_4.6_Mustang_GT.pdf?9690377850305210013

Get an upgraded fuel pump or even easier- add a boost-a-pump: http://kennebell.net/products/accessories/boost-a-pump/
 
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