Advice needed for Foxbody build

FireGT1017

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Hey everyone I just bought a 1989 GT, manual. The car's got the following modifications done to it:
- GT40 Cylinder heads
- GT40 ported Intake Manifold
- Fuel Sending Unit
- Fuel pump with filter sock
- 24Lb injectors
- 76 mm BBK Map sensor
- 75mm BBK throttle body
- BBK cold air intake
- BBK short tube headers
- Flowmaster catback
- Engines bored 40,000 over
- E303 cam

So the car runs fine but it's been sitting on a farm for 4 years, so I'm gonna take my sweet time getting this car restored for next summer. Just for my peace of mind, I will be pulling the engine and inspecting it to see it's condition because apparently the engine was rebuilt but I have doubts.

My questions:
A) Should I keep the GT40 Intake manifold (not installed yet) or should I sell it and instead get a Edelbrock RPM II

B) Should I keep the GT40 heads or instead just invest in some AFR 165's or 185's

C) Any other modifications I can do to get the most out of my engine?

D) Any engine care tips considering the cars been sitting for a while.

Goal: Have the car making 400hp, 400 ft lb's of trq

Sorry in advance if I'm missing important details, its my first post.
 
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7991LXnSHO

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400 hp from a 302 5.0 is pretty ambitious without a power adder. AFR or TW heads will help.What are your plans for using the car when the mice are all out? Restored does not need that high strung of an engine to be fun, as it will require other driveline upgrades to not break or just spin the wheels before blowing chunks of the transmission etc.

Have @tmoss port the lower explorer intake, and you will be happier with the torque curve on a driver.
 
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General karthief

wonder how much it would cost to ship you a pair
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Keep the gt40 heads, wait, let me backup
if you are pulling the engine to check out the condition and verify the work claimed and clean it up fine but it likely is not necessary, compression test and/or leak down test will tell you if the engine is in good shape.
Checking rubber and plastic vacuum lines is a must. The usual brake component inspection too.
Keep the gt40 heads and, as suggested above, have the lower intake ported, the rest of the list you provided can give the car a snappy, fun personality, but if you are truly looking at 400 hp you need to make an entirely new plan and in reality will likely be less 'fun' to cruise around in.
Check out some of the build threads in the fox forums and see what methods, parts and problems other members have encountered during their quest for driving nirvana.
 
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2000xp8

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I wouldn't pull the engine to inspect it.
I'd change the fluids, clean out the gas tank and lines and run it.
You'll know if it's good or not. If it isn't, pull it (which you were going to do anyway), if it's fine, you will have wasted alot of time.

Would i purposely run gt40 iron heads? Not a chance, but if they are on there and the car runs well, i'd just start compiling better parts if you want more power while i enjoyed the car or at least gave it a few month of good testing so you know what else has to go.
Right now you are probably in the 250 to 265rwhp range.
You are 100rwhp short of even being at 400 flywheel.
 
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Mustang5L5

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If you truly want 400HP, keep the engine that's in the car and just enjoy it. Don't touch a part on it

Buy a 331/347, toss on some TFS 11R heads, a good camshaft and a Trick FLow intake. When then engine is done being built, swap it and that will get your your 400HP goal.

A GT40 headed and GT40 intake car is a fun, torquey street motor. I wouldn't bother selling the GT40 intake (is it a tubular intake) for an edelbrock if you just have GT40 heads and an E303 cam. Run what you have.
 
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Steel1

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Supercharge it, about 10-12 lbs. of boost will get you to your goal.
I'm only half kidding.....you would need to upgrade injectors, possibly fuel pump and figure out how you want to tune it.
 
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FireGT1017

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Thanks everyone, I'll take your guys advice and change all the fluids then do a compression and leak test. I've seen articles like this one, "https://www.hotrod.com/articles/ford-302-v8-engine-buildup/" and assumed I could also make 400 with my current supporting mods plus AFR's, Carb and Intake manifold. After looking around the website I found cars bored out like mine with similar mods plus AFR 165's and at most they're making 340ish. Thanks for also clearing that misconception up, I'll just save up for a 347 stroker kit.
 

7991LXnSHO

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Thanks everyone, I'll take your guys advice and change all the fluids then do a compression and leak test. I've seen articles like this one, "https://www.hotrod.com/articles/ford-302-v8-engine-buildup/" and assumed I could also make 400 with my current supporting mods plus AFR's, Carb and Intake manifold. After looking around the website I found cars bored out like mine with similar mods plus AFR 165's and at most they're making 340ish. Thanks for also clearing that misconception up, I'll just save up for a 347 stroker kit.
Great and best of luck! Have fun with it while saving up for the bigger displacement setup. What you hopefully have should be fun with the torque band in the weight of the car.
 
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revhead347

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Supercharge it, about 10-12 lbs. of boost will get you to your goal.
I'm only half kidding.....you would need to upgrade injectors, possibly fuel pump and figure out how you want to tune it.

Best advice I have seen so far. I have an expensive stroker engine. An expensive stroker engine usually gets you 400hp. A reasonably priced blower kit always gets you 400hp. A good condition used blower kit gets you the same power for way less.

Like other's said, don't pull the engine. Logic. It runs well right now. If it wasn't rebuilt, it might fail, and you have fix it. If you pull it to see if it was rebuilt, and it wasn't, then you will fix it. The GT40 intake is a great intake that will run great with that cam. Slap it on there. Don't port it, the GT40 intake out flows the GT40 heads. That's money down the drain.

Kurt
 

7991LXnSHO

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I re-read the article from Hot Rod. I rarely call BS on their tech, but remember doing so when I first saw it. 50+ HP with a carb manifold on stock E-7 heads is the first questionable reading. And I've never heard of that kind of return from 1.7 rockers. They needed to post the power curves and check the dyno's calibration.
AFR heads are good as are TW, and I think the model was good for a 302. But without a cam, there was more left with the manifolds and heads that should have been needed to get above 400 HP, and it was probably high end, peaked power, Or a dyno calibration issue.
I plan on using heads much like that when I upgrade from seriously ported iron pieces and would be very happy with those numbers, driveability and survivability.
 
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General karthief

wonder how much it would cost to ship you a pair
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I agree with the above, keep in mind that was done in 2003 and was likely done to help sell the heads, if you google 'small block ford head comparison' you will get more recent head comparisons, I personally like the Engine Masters series,
 
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93 teal terror

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I more or less just picked up this kit (I sourced the parts individually).


Anderson has a dyno sheet for a similar but less comprehensive top end kit at 318.7 rwhp which is probably a whole lot like 370 fwhp.

Once I get everything installed, I'll dyno and tune it and post the numbers. Dyno'd previously at 209 rwhp with equal length headers, underdrive pullies, 75mm tbody, and 1.72 rr.

This is going on a stock ~190k 93 block.

Not sure it really answers your question but may be helpful as a point of reference.
 

MustangIIMatt

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I re-read the article from Hot Rod. I rarely call BS on their tech, but remember doing so when I first saw it. 50+ HP with a carb manifold on stock E-7 heads is the first questionable reading. And I've never heard of that kind of return from 1.7 rockers. They needed to post the power curves and check the dyno's calibration.
AFR heads are good as are TW, and I think the model was good for a 302. But without a cam, there was more left with the manifolds and heads that should have been needed to get above 400 HP, and it was probably high end, peaked power, Or a dyno calibration issue.
I plan on using heads much like that when I upgrade from seriously ported iron pieces and would be very happy with those numbers, driveability and survivability.

I actually have the issue of Car Craft where they built that engine. There's info missing from the online article on Hot Rod's website (like there is on so many articles since the magazines all died off/merged/contracted). You've also got to take into account that the stock "225 horsepower" of that '91 Mustang engine that they started with was SAE net horsepower, meaning it was achieved running full accessories, where as their run with just a water pump on the dyno had about 20-25 horsepower less parasitic drag. The engine didn't magically gain 50+ from the carb/intake swap, it picked up 20-25 and lost 20-25 in parasitic drag. The article is also missing the full parts list for what went into the engine. The short block and cam really were stock, but they played with springs, rocker arms, carburetor jets and more to keep getting another horsepower here or there until they just barely got over the 400hp mark.

To put it into perspective, this is the basis for my current engine: https://mustangsandmore.com/ubb/BudgetSmallBlock.html I have 1.7 roller rockers, and only went .040" over instead of .060", but 267rwhp out of an iron-headed naturally-aspirated 308cid engine is, well, something that some would try to say can't be done, but if Alex Denysenko could do it, and then I could replicate it in my driveway, then it obviously can. The heads used in that old Car Craft article would probably get me close to 400rwhp, but that'd be the easy way, and you know we don't do that 'round here... :rlaugh:
 

Willybill32

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I more or less just picked up this kit (I sourced the parts individually).


Anderson has a dyno sheet for a similar but less comprehensive top end kit at 318.7 rwhp which is probably a whole lot like 370 fwhp.

Once I get everything installed, I'll dyno and tune it and post the numbers. Dyno'd previously at 209 rwhp with equal length headers, underdrive pullies, 75mm tbody, and 1.72 rr.

This is going on a stock ~190k 93 block.

Not sure it really answers your question but may be helpful as a point of reference.
I’m a bit of a noobie here, but my original ‘86 5.0 with 98K was redone in the last year with TW 170 heads, E303 cam, Comp Cams 1.6 roller rockers, BBK fuel rails and regulator, 24 lb injectors, BBK 65mm throttle body and 76mm MAF, and Bassani equal-length ceramic shorties. My car dyno’d at 314 HP and 346 lbs-ft.

Being the original owner, I’d collected most of the parts over the years. A friend who helped me wanted to keep it stock, but I wanted to use my parts. My only second thought is on the cam, as my tuner says it causes some “bucking” I notice at real low speeds.
 

MustangIIMatt

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I’m a bit of a noobie here, but my original ‘86 5.0 with 98K was redone in the last year with TW 170 heads, E303 cam, Comp Cams 1.6 roller rockers, BBK fuel rails and regulator, 24 lb injectors, BBK 65mm throttle body and 76mm MAF, and Bassani equal-length ceramic shorties. My car dyno’d at 314 HP and 346 lbs-ft.

Being the original owner, I’d collected most of the parts over the years. A friend who helped me wanted to keep it stock, but I wanted to use my parts. My only second thought is on the cam, as my tuner says it causes some “bucking” I notice at real low speeds.
I love seeing "alphabet" cam builds that work.

The alphabet cams are yester-year's tech, nobody will ever get argument from me there, but a lot of people act like they magically quit bumping lifters up when more modern camshaft designs came along. They still work, not as well as some of the newer tech, but when you can pick them up used on CL, FB, or a swap meet for next to nothing sometimes... they can be very cost effective, sound good, and make pretty decent power for the dollar when used in a well-thought-out setup like your own.
 

revhead347

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I love seeing "alphabet" cam builds that work.

The alphabet cams are yester-year's tech, nobody will ever get argument from me there, but a lot of people act like they magically quit bumping lifters up when more modern camshaft designs came along. They still work, not as well as some of the newer tech, but when you can pick them up used on CL, FB, or a swap meet for next to nothing sometimes... they can be very cost effective, sound good, and make pretty decent power for the dollar when used in a well-thought-out setup like your own.

The other side of that is when you price out a build, the cam is so cheap in the big picture no matter what you get. I would never recommend running an alphabet cam. I totally get how times change. I have 192cc cylinder heads. Would you believe that they were the biggest streetable cylinder head you could get at the time? At the time, the next step from the Canfield was the big Neal racing heads that you could never run on a street car.

Kurt
 
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Willybill32

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The other side of that is when you price out a build, the cam is so cheap in the big picture no matter what you get. I would never recommend running an alphabet cam. I totally get how times change. I have 192cc cylinder heads. Would you believe that they were the biggest streetable cylinder head you could get at the time? At the time, the next step from the Canfield was the big Neal racing heads that you could never run on a street car.

Kurt
Knowing what I know now, I’d look for a more modern cam than my E303...but it’s still a learning experience!
 

revhead347

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Knowing what I know now, I’d look for a more modern cam than my E303...but it’s still a learning experience!

Not to mention changing a cam is an 8 hour :poo: job where half the time you get 8 more hp, but now you have an oil leak. But yeah, if you are starting from scratch definitely get a better cam.

Kurt