Thinking of building a new engine for my 95 GT

[maillemaker]

So, my 1995 Mustang GT has low oil pressure. Reading 20 PSI at speed, 3-5 PSI at idle when hot.

I'm guessing worn out main bearings.

I'm thinking of slowly building a new engine to swap out with the old one.

I'd like to make 300 HP.

Here is a place I could get a short block:

Ford 5.0 302 Short Block 1982-1995 - NO CORE REQUIRED - 90 Day Limited Warranty

I was thinking of putting on some higher flowing aftermarket aluminum heads, and a higher flowing intake manifold. And a better cam.

Going to stick with my factory headers and would like to run the engine with the stock ECU and wiring harness.

I'd like the engine to continue to run on 87 octane gas.

Car will only be driven as a daily driver. I seldom go over 3000 RPM.

What do you all think?

 

[95opal]

300hp with stock headers and 87 octane is a stretch.

 

[maillemaker]

300hp with stock headers and 87 octane is a stretch.

Do SN95 Cobras require premium gas?

 

[green5point0]

That looks fairly expensive. To have OE spec replacements would require adding hundreds of dollars of options to the $999 sticker. The flat top cast pistons and flat tappet lifters being a couple of examples. I’m far from an expert but it might be worth considering other options.

It makes a lot of sense to get a new motor ready before you pull the old one if you want to minimize down time driving the car though. Looking forward to seeing progress pics and finding out what you do.

 

[maillemaker]

That looks fairly expensive. To have OE spec replacements would require adding hundreds of dollars of options to the $999 sticker. The flat top cast pistons and flat tappet lifters being a couple of examples. I’m far from an expert but it might be worth considering other options.

It makes a lot of sense to get a new motor ready before you pull the old one if you want to minimize down time driving the car though. Looking forward to seeing progress pics and finding out what you do.

I have no idea what costs are involved here. I figured getting a complete short block for around $1000 was a pretty good deal.

Here is one for $795 (plus core):

Ford 5.0 302 Short Block Engine Sale, Remanufactured not Rebuilt

Our Ford 5.0 liter Engine is on Sale. Much more than a rebuilt 302 Short Block Engine, this OEM replacement is completely remanufactured with upgraded parts.

spprecision.com

But I don't know what kind of pistons I'll need to go with heads, etc. Don't know how to compute compression yet, either. I've never built a 302. Last engine I built was for a 79 Chevette about 30 years ago.

 

[Musturd]

the last thing I’d wanna do is run 87 octane on my fresh engine with nice heads . Personally I’d get aftermarket headers as well

 

[maillemaker]

the last thing I’d wanna do is run 87 octane on my fresh engine with nice heads . Personally I’d get aftermarket headers as well

If I can't build a 300 HP engine that will run on 87 octane then I guess I'll probably just get a stock longblock and swap everything over onto it.

The thing is expensive to run already at 15 MPG with 87 octane...don't want to have to put 89 or 93 in it for a daily driver.

 

[RAU03MACH]

That seem a little low price
Makes no sense I'm paying 581 for an intake
And over 2 grand for a set of heads
Hmm 795 I don't know

 

[Musturd]

If I can't build a 300 HP engine that will run on 87 octane then I guess I'll probably just get a stock longblock and swap everything over onto it.

The thing is expensive to run already at 15 MPG with 87 octane...don't want to have to put 89 or 93 in it for a daily driver.

Run it on e85 if you got it around you and don’t wanna spend money on 93 . I just find it confusing you wanna build the engine up and still run it on the worst possible fuel available .

 

[maillemaker]

Run it on e85 if you got it around you and don’t wanna spend money on 93 . I just find it confusing you wanna build the engine up and still run it on the worst possible fuel available .

I hoped it would be possible to get more horsepower while still running 87 octane gas for cost reasons. I would think that increased airflow and overboring would give me better HP even without increasing compression?

 

[Randall Garner]

Yes 300 hp at the flywheel can be ran on 87, there are full race big blocks out there making 7-800 hp on 93. It requires the right parts and a bit of math. Compression needs to be kept under 10.0 static. Most short blocks are under 10.0. As far as 95 blocks . They are hydraulic roller cammed. Which means there is a thousand different cams available. You need to talk to hum ever your thinking for heads. I have read about AFR enforcer series. Appears to be a pretty decent head for a stock , mild build. Rhs has a good head that in the same price range. If your smart about the parts. Know the math, and the parts are working together , for the best bang for the buck. 300-350 is doable all day long. If you can find a 347 short block. It'll be much easier to accomplish your goal. I have a 94 347 stroker in a early ford . Runs on 87 . Just fine with timing pulled back just a few degrees probably near 400 HP.

 

[302hobronco]

Go to the junkyard and get the explorer top end, gt40 heads and intake. Get a cam with 114 lobe sep or greater and with a new short block, those parts and some work on your part. (Modify throttle linkage and some hoses) you could be real close or just at 300hp.
My previous engine was the stock 94 short block. Gt40 heads, milled .040 off them. Ported lower explorer intake and upper intake. Modified stock tb linkage, 4 hole 19lbs injectors, comp nx264hr cam, 1.7rr, full exhaust. It ran very strong and reliable. 18mpg and I was not easy on it. I did run premium though. And eventually I did a bama tune. But it was very spirited.

 

[Wood's 5.0]

Stock 94-95 Cobras came with 240 (factory rated) flywheel horsepower, IIRC. That's with REAL GT-40 heads with 1.6 Cobra roller rockers (made by Crane, IIRC), a REAL Cobra upper & lower intake, don't remember about the TB and MAF, #24 injectors, a 5-speed manual, and an "E" Motorsport/SVO cam (which was made by Crane, IIRC). With a good set of aluminum heads, top-shelf intake, a good cam that will play well with the automatic and computer (ask me how I know. Consider a Ford Racing "E" or a Steeda #19 cam), matching 65mm TB, 77 or so mm MAF, and #24 injectors and an upgraded fuel pump (IIRC, a 190 lph. is good to about 375-400 HP), 300 RWHP on regular pump gas is not unrealistic. 93 would be better but regular should work. If I am incorrect then I will stand corrected. If you are going to try this at home, you could rebuild your stock block; .030 over equals a 306 IIRC and that will help it a bit. However and IMO, you might as well stroke it to a 331 or 347 and match the components accordingly. Now 300 RWHP is (or at least should be) easily attainable and then some. Really should not be a whole lot of additional expense in machine work either; couple hundred bucks, maybe? Doing so will make it a different animal compared to what you have now. Not going to help you on fuel mileage either but after feeling it when you mash the right pedal you prolly will let that part slide . Also, you won't see that 300 RWHP below 3,000 RPMs either; more like in the 3,500 - 5,000 range so at that level fuel mileage is out the window any way. You will also need it dyno tuned to really maximize the performance potential of the package you assemble; ours requires a chip attached to the back of the computer which is in the passenger's front kick panel. Not talking down to you or being condescending I just don't know how familiar you are with the subject so please do not take offense as that is not my intent. I bought mine brand new, didn't make a lot of money, and used it as my daily driver for several years so I understand your concern regarding reliability and expense to operate. Our headers, believe it or not, actually flow pretty well. Not as well as a good set of aftermarkets but fairly well for a production part. IMO, a full exhaust would be a must-have. However, if you want the stock exhaust then right on and bolt it right up - it will fit and work. Lots of people here way more knowledgeable than I so please take all offers of advice, figure out what will work best for you and your goals, make a plan, and carry on. My experience with this stuff was when it was all new and I have been down this rabbit hole. Things have certainly changed since 1994 -1995 so my experience and information may be outdated. Keep us in the loop with good pictures and narration like you did with the gauges. Like most here, I am glad to help or offer my advice/opinion whenever I can. Oh, another option I almost forgot to mention. Not that I'm a fan or proponent as I am an "All throttle, no bottle" kind of guy buy you could always slap a 125 shot of the giggle gas on it and call it a day. That would give you 300 to the dirt on-demand and you could be done with it in an evening. Didn't know if you considered that or not. Anyway, take care and good luck.

 

[maillemaker]

I originally thought of doing a 347 stroker, but holy cow things get expensive in a hurry. I saw some YouTube videos of people porting the bottoms of the cylinder bores with a carbide bit to clear the connecting rods...I could do it myself. But really, I'm not looking for a 400+ monster. Just would like a little extra pep getting off the line. I don't speed and this is a daily driver. I think 300+ HP would do fine.

I was thinking a low-compression setup with a better-flowing set of heads and intake, like GT40 or aftermarket. Was also going to go with roller lifters and roller rockers.

I'll need to figure out how to compute compression. I know there are online tools.

 

[maillemaker]

Stock 94-95 Cobras came with 240 (factory rated) flywheel horsepower, IIRC. That's with REAL GT-40 heads with 1.6 Cobra roller rockers (made by Crane, IIRC), a REAL Cobra upper & lower intake, don't remember about the TB and MAF, #24 injectors, a 5-speed manual, and an "E" Motorsport/SVO cam (which was made by Crane, IIRC). With a good set of aluminum heads, top-shelf intake, a good cam that will play well with the automatic and computer (ask me how I know. Consider a Ford Racing "E" or a Steeda #19 cam), matching 65mm TB, 77 or so mm MAF, and #24 injectors and an upgraded fuel pump (IIRC, a 190 lph. is good to about 375-400 HP), 300 RWHP on regular pump gas is not unrealistic. 93 would be better but regular should work. If I am incorrect then I will stand corrected. If you are going to try this at home, you could rebuild your stock block; .030 over equals a 306 IIRC and that will help it a bit. However and IMO, you might as well stroke it to a 331 or 347 and match the components accordingly. Now 300 RWHP is (or at least should be) easily attainable and then some. Really should not be a whole lot of additional expense in machine work either; couple hundred bucks, maybe? Doing so will make it a different animal compared to what you have now. Not going to help you on fuel mileage either but after feeling it when you mash the right pedal you prolly will let that part slide . Also, you won't see that 300 RWHP below 3,000 RPMs either; more like in the 3,500 - 5,000 range so at that level fuel mileage is out the window any way. You will also need it dyno tuned to really maximize the performance potential of the package you assemble; ours requires a chip attached to the back of the computer which is in the passenger's front kick panel. Not talking down to you or being condescending I just don't know how familiar you are with the subject so please do not take offense as that is not my intent. I bought mine brand new, didn't make a lot of money, and used it as my daily driver for several years so I understand your concern regarding reliability and expense to operate. Our headers, believe it or not, actually flow pretty well. Not as well as a good set of aftermarkets but fairly well for a production part. IMO, a full exhaust would be a must-have. However, if you want the stock exhaust then right on and bolt it right up - it will fit and work. Lots of people here way more knowledgeable than I so please take all offers of advice, figure out what will work best for you and your goals, make a plan, and carry on. My experience with this stuff was when it was all new and I have been down this rabbit hole. Things have certainly changed since 1994 -1995 so my experience and information may be outdated. Keep us in the loop with good pictures and narration like you did with the gauges. Like most here, I am glad to help or offer my advice/opinion whenever I can. Oh, another option I almost forgot to mention. Not that I'm a fan or proponent as I am an "All throttle, no bottle" kind of guy buy you could always slap a 125 shot of the giggle gas on it and call it a day. That would give you 300 to the dirt on-demand and you could be done with it in an evening. Didn't know if you considered that or not. Anyway, take care and good luck.

Thanks, great info.
I have considered rebuilding the engine in the car but I do not want the car to be out of service that long. If I build a new engine I can swap it out in a week or two.

 

[Wood's 5.0]

@maillemaker
Yes, sir, they surely can and do. A real GT-40 intake is old-school cool. Beware the fakes or what people call a GT-40. Below is a link to a real one and a picture of the one I had on my 90 GT 'vert.

1986-1995 Ford Mustang GT40 Tubular Upper Intake Manifold Cobra 5.0 302 5.8 351 | eBay

Find many great new & used options and get the best deals for 1986-1995 Ford Mustang GT40 Tubular Upper Intake Manifold Cobra 5.0 302 5.8 351 at the best online prices at eBay! Free shipping for many products!

www.ebay.com

 

[RAU03MACH]

I may be putting this engine up for sale
Once my 351 is done
It has quite a few mods

 

[302hobronco]

Just some food for thought on the gt40 heads with a very mild 94-95 friendly cam.
Granted I know the exhaust and induction is not what the OP will be running. But it shows what a good cam and the gt40s is capable of.

 

[maillemaker]

Just some food for thought on the gt40 heads with a very mild 94-95 friendly cam.
Granted I know the exhaust and induction is not what the OP will be running. But it shows what a good cam and the gt40s is capable of.

Thanks, I've watched a lot of his videos.

 

[Randall Garner]

I originally thought of doing a 347 stroker, but holy cow things get expensive in a hurry. I saw some YouTube videos of people porting the bottoms of the cylinder bores with a carbide bit to clear the connecting rods...I could do it myself. But really, I'm not looking for a 400+ monster. Just would like a little extra pep getting off the line. I don't speed and this is a daily driver. I think 300+ HP would do fine.

I was thinking a low-compression setup with a better-flowing set of heads and intake, like GT40 or aftermarket. Was also going to go with roller lifters and roller rockers.

I'll need to figure out how to compute compression. I know there are online tools.

I have a 347, did not require any clearancing . Sure that wasnt for a 363 stroker, I see a lot of people talking the gt40 heads. But you still get better gains with a aluminum head with much better flow