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Discussion Starter · #1 ·
I have a 94 GT, just bought it in sad shape this summer, got it back to decent condition just in time to park for winter. It's absolutely stock and unmolested. 250k miles but the motor feels tight.

I've replaced the timing chain and harmonic balancer. Not really in the mood to put a cam in, and there's no budget for a new set of heads and exhaust headers (as I understand the spark plug angle is a problem with different heads.. )

So... other than a cam and heads, what else should I do with the top of the engine as long as I'm putting a Cobra intake manifold on? Do aluminum valve covers fit under the Cobra manifold? Should I put new valve springs and rockers on?

Specifically talking about stuff on the top of the engine that's accessible with the intake removed, not talking about chassis stuff or exhaust stuff.

Thanks!
 

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I'd consider swapping from the 19lb UREMCO style injectors to some 19lb Jetronic style injectors commonly found on Explorers. The four hole Jetronic style injectors give better fuel atomization than the single hole UREMCO. No need to mess with the MAF either, as they're both 19lb injectors.

Maybe a 70mm or 75mm throttle body if you can find one.

New PCV valve and screen.

1.7 rockers if you're up for it. Would go well with the intake swap.

That would be a pretty solid start to the mod list: fresh Intake, better injectors, throttle body, rockers.
 
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Plug angle is only an issue on gt40p heads which are straight. Stock and aftermarket heads have angled plugs AFAIK. I'm not aware of any aftermarket heads that are straight plug angle. 87-93 aluminum covers won't fit due to the alternator. You can clearance them to make them work but the oil fill often causes issues. Aftermarket valve covers almost never fit without an intake spacer. I personally wouldn't put money into roller rockers on the stock heads with a stick cam. Do rockers when you do a nice set of heads. The stock hole on the intake is 65mm if i remember correct. 70 or 75mm tb wouldn't help without increasing the hole and even then without porting especially with stock heads, It's not going to really help.
 

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Get a good set of valve cover gaskets. Something like the Felpro’s that are metal w a rubber coating. I believe the call them Perma-dry. I don’t think I’d spend any money on valve covers though since you can’t hardly see them anyway on ‘94/‘95’s. If it has the stock strut tower brace I don’t believe it’ll clear the explorer intake.
Where’s Waldo? He’s on the valve covers but you can’t hardly see ‘em.
 

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Discussion Starter · #5 ·
I figured I would need the BBK strut tower brace, it's funny how you can pretty quickly add up to the price of a newer, faster Mustang piece by piece on these old ones. Especially if you're trying to do things cleanly rather than cobbling together scrapyard pieces.
 

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I figured I would need the BBK strut tower brace, it's funny how you can pretty quickly add up to the price of a newer, faster Mustang piece by piece on these old ones. Especially if you're trying to do things cleanly rather than cobbling together scrapyard pieces.
I hear you on how it takes relatively a lot of money to add one part because it requires a bunch of other parts to make that one part work. Cylinder heads for instance. If one is starting from stock even a set of $900 knock-off heads will turn into several thousand and that’s not even with a new manifold. If you could just slap on the heads and go it’d be good. But you’d need all of the miscellaneous stuff (gaskets, bolts, maybe pushrods, etc, etc. As well as fuel, injectors, fuel pump, and some sort of way to tune it. Even after all of that it really wouldn’t be worth a darn w/out a new intake manifold so that’s another pretty big chunk of change. It’s kinda the pits.
 

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Discussion Starter · #7 · (Edited)
It’s kinda the pits.
The money thing of course is common to any platform right? How fast do you want to go and how much money do you have are the same question.

I'll be pretty satisfied I think with modest horsepower; my truck makes 400 and my jeep makes 170.. the Mustang is supposedly 215 and I don't have a target in mind I just want it to pull over 5k rpm so it's rewarding to stay in the gas a little longer.. right now while getting on the highway I feel like shifting at 4k because it's rough and gutless above that.

So instead of a horsepower target my target is I want it smooth as butter up to at least near the top of the tach.

What's difficult for me at this time is knowing what works with what. I come from working on Mitsubishi engines and I have fair skills, tools and patience under the hood but I'm new to small block Fords.

Well I know mine feels rough and weak over 4k rpm, everyone says the stock valve springs are junk and mine have a quarter million miles on them.. so a new set of springs sounds like a good idea and maybe an upgraded (lighter, stiffer) set of rockers.

But there are so many choices and I can't tell what works with what! Some things will or won't clear the valve covers, some valve covers will or won't clear the intake, there are pedestal and stud mount rockers, I don't even know what that means. There are 7/16 and 3/8 studs, some rockers need guide plates and some don't. There's something about the exhaust valves spinning and some valve springs don't work with that... I can't find anywhere to read into this other than chit chat on forums with no in-depth discussion. I don't even want to get into changing rocker ratio because then I need to take the heads off to clay the pistons and I really don't feel like taking the heads off unless they're getting upgraded but then.. like you said, another $2k+ worth of assorted parts.

Really I'll be happy with ~225-250 horsepower as long as it's smooth, my wife's 3.8 New Edge is smoother than this 5.0 🤣😂

Where can I go to learn what works with what? I hate guessing! Is there a 302 bible I can buy?
 

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The money thing of course is common to any platform right? How fast do you want to go and how much money do you have are the same question.

I'll be pretty satisfied I think with modest horsepower; my truck makes 400 and my jeep makes 170.. the Mustang is supposedly 215 and I don't have a target in mind I just want it to pull over 5k rpm so it's rewarding to stay in the gas a little longer.. right now while getting on the highway I feel like shifting at 4k because it's rough and gutless above that.

So instead of a horsepower target my target is I want it smooth as butter up to at least near the top of the tach.

What's difficult for me at this time is knowing what works with what. I come from working on Mitsubishi engines and I have fair skills, tools and patience under the hood but I'm new to small block Fords.

Well I know mine feels rough and weak over 4k rpm, everyone says the stock valve springs are junk and mine have a quarter million miles on them.. so a new set of springs sounds like a good idea and maybe an upgraded (lighter, stiffer) set of rockers.

But there are so many choices and I can't tell what works with what! Some things will or won't clear the valve covers, some valve covers will or won't clear the intake, there are pedestal and stud mount rockers, I don't even know what that means. There are 7/16 and 3/8 studs, some rockers need guide plates and some don't. There's something about the exhaust valves spinning and some valve springs don't work with that... I can't find anywhere to read into this other than chit chat on forums with no in-depth discussion. I don't even want to get into changing rocker ratio because then I need to take the heads off to clay the pistons and I really don't feel like taking the heads off unless they're getting upgraded but then.. like you said, another $2k+ worth of assorted parts.

Really I'll be happy with ~225-250 horsepower as long as it's smooth, my wife's 3.8 New Edge is smoother than this 5.0 🤣😂

Where can I go to learn what works with what? I hate guessing! Is there a 302 bible I can buy?
Well my ‘95 GT made 205 rear horse with a fresh 306 and everything else stock other than a .512 lift 281 duration cam & Comp “beehive springs.” After having the lower intake ported it made 223 rear horse and with a 6-8 psi supercharger kit it makes 332. My exhaust system is “basic” as well. Stock headers, stock mid pipe w the front cats removed n the rears replaced with “high flows” followed by chambered mufflers. It sounds nice.
The typical 170cc ish aftermarket cylinder head with “matching” intake and cam makes in the 300 rear horse ballpark. GT40 headed combos make somewhere in the 240-270 rear horse ballpark.
Here’s a good read on “bolt-on” mods. The gist of it is that they’re worth very little with a stock motor. If me met severs they “test” 1.7 rockers in this article as well.
 

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The money thing of course is common to any platform right? How fast do you want to go and how much money do you have are the same question.

I'll be pretty satisfied I think with modest horsepower; my truck makes 400 and my jeep makes 170.. the Mustang is supposedly 215 and I don't have a target in mind I just want it to pull over 5k rpm so it's rewarding to stay in the gas a little longer.. right now while getting on the highway I feel like shifting at 4k because it's rough and gutless above that.

So instead of a horsepower target my target is I want it smooth as butter up to at least near the top of the tach.

What's difficult for me at this time is knowing what works with what. I come from working on Mitsubishi engines and I have fair skills, tools and patience under the hood but I'm new to small block Fords.

Well I know mine feels rough and weak over 4k rpm, everyone says the stock valve springs are junk and mine have a quarter million miles on them.. so a new set of springs sounds like a good idea and maybe an upgraded (lighter, stiffer) set of rockers.

But there are so many choices and I can't tell what works with what! Some things will or won't clear the valve covers, some valve covers will or won't clear the intake, there are pedestal and stud mount rockers, I don't even know what that means. There are 7/16 and 3/8 studs, some rockers need guide plates and some don't. There's something about the exhaust valves spinning and some valve springs don't work with that... I can't find anywhere to read into this other than chit chat on forums with no in-depth discussion. I don't even want to get into changing rocker ratio because then I need to take the heads off to clay the pistons and I really don't feel like taking the heads off unless they're getting upgraded but then.. like you said, another $2k+ worth of assorted parts.

Really I'll be happy with ~225-250 horsepower as long as it's smooth, my wife's 3.8 New Edge is smoother than this 5.0 🤣😂

Where can I go to learn what works with what? I hate guessing! Is there a 302 bible I can buy?
You'd want 1.7 Pedestal Mount rockers for your factory e7 heads.
Stock 6.250 length pushrods will work.
Stock SN95 valve covers will work.
No need to clay the pistons; e7 heads have a very small valve size at 1.78/1.45 and you'd effectively only be raising the lift of your stock cam by about 0.33/0.33 for a minor bump in power. The pedestal mount rocker upgrade is worth it.

My 94 GT made 212hp/278ft.lbs with only 1.7 rockers, X-pipe, 75mm throttle body, explorer injectors, 255 fuel pump
Rectangle Slope Line Font Parallel


I put a Nitrous Outlet X-series kit on it jetted for the smallest possible shot (35) and it made 252hp/361ft.lbs.
Rectangle Slope Font Parallel Pattern


Here's a picture of the engine. Still had stock headers, stock e7 heads, stock GT intake, stock bottom end...
Motor vehicle Automotive design Vehicle Automotive air manifold Car


I wouldn't steer you in the wrong direction by suggesting something I hadn't done myself. These small mods definitely wake up these SN95s. The engine I was working with had an unknown amount of miles on it because the odometer was broken. It was something over 150k. The previous owner had neglected it in a major way and I was able to save it from getting parted out. But anyways, this stuff is a good starting point, it's not entirely expensive, and it's easy to do. I hope you get what you're looking for out of your mods.
 

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You'd want 1.7 Pedestal Mount rockers for your factory e7 heads.
Stock 6.250 length pushrods will work.
Stock SN95 valve covers will work.
No need to clay the pistons; e7 heads have a very small valve size at 1.78/1.45 and you'd effectively only be raising the lift of your stock cam by about 0.33/0.33 for a minor bump in power. The pedestal mount rocker upgrade is worth it.

My 94 GT made 212hp/278ft.lbs with only 1.7 rockers, X-pipe, 75mm throttle body, explorer injectors, 255 fuel pump
View attachment 1078789

I put a Nitrous Outlet X-series kit on it jetted for the smallest possible shot (35) and it made 252hp/361ft.lbs.
View attachment 1078790

Here's a picture of the engine. Still had stock headers, stock e7 heads, stock GT intake, stock bottom end...
View attachment 1078791

I wouldn't steer you in the wrong direction by suggesting something I hadn't done myself. These small mods definitely wake up these SN95s. The engine I was working with had an unknown amount of miles on it because the odometer was broken. It was something over 150k. The previous owner had neglected it in a major way and I was able to save it from getting parted out. But anyways, this stuff is a good starting point, it's not entirely expensive, and it's easy to do. I hope you get what you're looking for out of your mods.
I think you might’ve made the same with the stock TB. Apples & oranges, but when I went from the stock ‘95 TB to a 65mm I didn’t feel anything different. I went 65mm bc it matches the stock intake open the best. Maybe I should’ve went 70mm but I don’t think the TB is ever going to be a restriction with E7 heads.
 

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I think you might’ve made the same with the stock TB.
I think I might have made more with the 75mm. We can't really back up either of our claims without proven data.

But now that we're on the subject of TB's and whatnot, heres a BBK dyno test of a stock SN95 5.0 going from 100% stock trim to a 70mm throttle body and their cold air induction. Take it for what it's worth, as it's a company ran test. Through an AOD.
Rectangle Product Slope Plot Line



I don’t think the TB is ever going to be a restriction with E7 heads.
This statement I can agree with.
 

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Discussion Starter · #12 ·
I figured I probably wouldn't fool with the throttle body just yet, that's easy to do later anyway if I decide to but it seemed like the two biggest bottlenecks outside the heads are the stock intake manifold - both its average restriction and in particular the huge difference in flow between different runners - and the stock mid pipe.

I have a BBK catted midpipe in the garage ready to go in, got the 94/95 cobra intake manifold that needs to get cleaned up a little but basically ready. Just need to figure out what 1.7 rockers to pick up and what springs will work with them I guess and pick up all the random gaskets/etc needed.

Still a few more weeks of driving weather, maybe we'll take a short road trip next weekend then put the Mustang away for the season.

Somewhat related, I made this little chart using data I found on various forums, take it with a grain of salt since it's from random people and not verified or validated by anyone.

Rectangle Product Azure Slope Font
 

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I think I might have made more with the 75mm. We can't really back up either of our claims without proven data.

But now that we're on the subject of TB's and whatnot, heres a BBK dyno test of a stock SN95 5.0 going from 100% stock trim to a 70mm throttle body and their cold air induction. Take it for what it's worth, as it's a company ran test. Through an AOD.
View attachment 1078822




This statement I can agree with.
24 horsepower from a throttle body!? Get it together BBK. These are the days of the internet, we know things now. 😂
Back when K&N filters first hit the scene they claimed 25 horsepower from a drop in filter.
 

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Discussion Starter · #14 · (Edited)
While distracted at work I threw some numbers into excel and worked out approximately how much value 1.7 rockers can provide on E7 heads, based on the scattered (plausible) information I was able to find from a number of google searches. Seems a lot of people have put E7 heads on flow measurement tools and achieved all sorts of different results so I took all the results I could find that seemed close to each other and averaged them. Not very scientific but I'm not landing robots on other planets here so it's OK.

The results are minimal because even though a higher ratio does very little at small cam elevations and a lot at maximum cam elevation, the E7 heads plateau on flow already with 1.6 rockers so most of the benefit really shows up in the early and late events, the valve is a little more open a little earlier and stays a little more open a little later.

Light Rectangle Azure Slope Plot

BTW if anyone reads this and is better at Excel than I am, a lot of those values were done "by eye" because I don't know how to calculate off a trendline. If you know how to calculate off a trendline directly I can share my sheet somewhere and you can improve the accuracy of these numbers.
 

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While distracted at work I threw some numbers into excel and worked out approximately how much value 1.7 rockers can provide on E7 heads, based on the scattered (plausible) information I was able to find from a number of google searches. Seems a lot of people have put E7 heads on flow measurement tools and achieved all sorts of different results so I took all the results I could find that seemed close to each other and averaged them. Not very scientific but I'm not landing robots on other planets here so it's OK.

The results are minimal because even though a higher ratio does very little at small cam elevations and a lot at maximum cam elevation, the E7 heads plateau on flow already with 1.6 rockers so most of the benefit really shows up in the early and late events, the valve is a little more open a little earlier and stays a little more open a little laterr
View attachment 1078862
BTW if anyone reads this and is better at Excel than I am, a lot of those values were done "by eye" because I don't know how to calculate off a trendline. If you know how to calculate off a trendline directly I can share my sheet somewhere and you can improve the accuracy of these numbers.
Super Ford say they gained 4.3 hp with 1.7’s. Which could either mean they gained near five, zero, or maybe more but doubtful. A dyno won’t read the same thing twice really and 4.3 hp could’ve been gained or lost (according to the dyno) with no other changes made.
Slap the manifold on and call it good.
 

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Discussion Starter · #16 ·
Super Ford say they gained 4.3 hp with 1.7’s. Which could either mean they gained near five, zero, or maybe more but doubtful.
That's actually reassuring, if you look at the sum of all differences in flow (the red text in black cells at the lower right corner of that graphic I posted) it's almost exactly a 3% increase in flow. The cam doesn't spend precisely the same amount of time at each aperture but that's the amount of difference you would realize if it did. A 3% increase on 215 horsepower is in the vicinity of 5 and 4.3 is also in the vicinity of 5 so that's the expected result.

I didn't do the math in order to talk myself into doing more work, I just like working out numbers as a reality check and it's reassuring that the prediction is relatively inline with somebody's observed result.
 

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I wouldn't do anything to the stock engine unless it's a full H/C/I + tune all at once. Better mods would be full exhaust, and 3.73 or 4.10 gears with better rear control arms for now. If you have a 5 speed those mods can get you into the 13.8-14.0 quarter mile zone with sticky tires. An intake, 1.7 rockers, and throttle body won't do anything you can feel at this stage.
 

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I wouldn't do anything to the stock engine unless it's a full H/C/I + tune all at once. Better mods would be full exhaust, and 3.73 or 4.10 gears with better rear control arms for now. If you have a 5 speed those mods can get you into the 13.8-14.0 quarter mile zone with sticky tires. An intake, 1.7 rockers, and throttle body won't do anything you can feel at this stage.
I gained 18 horse by having the stock lower intake manifold ported and I could feel it. Prior to that I went from 2.73 to 3.73. I could feel that too but it was mostly just feel. I’ve since went to a 3.31 gear and I prefer that “feel” to the 3.73’s.
 

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Discussion Starter · #19 ·
I considered sending my stock intake off to Big Dogs for porting but with that 21% difference between the worst and best runners it seemed like the best option would be just trying to bring the two worst ones up enough to match the rest. I'm not saying it would be wasted effort but basically every other choice starts out much closer to balanced and with tons more airflow so it was hard for me to make a case for keeping the stock one. It's still an option though if something goes wrong with the Cobra intake install.

I'm pretty sure my axle has 3.08 gears, I'm OK with that - if I ever decide to change the diff out for a helical LSD I might try to put some 3.31 or 3.55 gears in at the same time but that's way over the horizon at the moment. My wife's V6 has 3.27's and it definitely needs 3.73's :)
 

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I considered sending my stock intake off to Big Dogs for porting but with that 21% difference between the worst and best runners it seemed like the best option would be just trying to bring the two worst ones up enough to match the rest. I'm not saying it would be wasted effort but basically every other choice starts out much closer to balanced and with tons more airflow so it was hard for me to make a case for keeping the stock one. It's still an option though if something goes wrong with the Cobra intake install.

I'm pretty sure my axle has 3.08 gears, I'm OK with that - if I ever decide to change the diff out for a helical LSD I might try to put some 3.31 or 3.55 gears in at the same time but that's way over the horizon at the moment. My wife's V6 has 3.27's and it definitely needs 3.73's :)
The reason I went w the ported lower was because it was a little cheaper. At the time Explorer “GT40” intakes we’re running around $300 and I’d still need to buy the $100’ish elbow adapter to make it work. Granted it was around $300 to have the lower ported. Having the lower ported didn’t leave me with any growing room but neither does my wallet so it is what it is I guess. Even if I went with the Explorer intake you’d probably want the lower ported if you went with anything other than GT40 heads. So then you’d be into it for $300 for the intake, $100 for the elbow, and another $300 to have it ported. By that time one could’ve bought a “better” brand new intake.
 
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