Skip to main content ↑ ↓
Topic: 87 EFI Mods? (Read 1241 times) previous topic - next topic

87 EFI Mods?

I have a 87 Cougar XR7 with the standard EFI 5.0 motor. I do no want to swap to an HO. I have one already in my 94 Stang GT. I want keep this car real driveable/streetable. I need to know what kind of upgrades and WHERE to get them. Headers, Exhaust System, Cold Air. Anything, Timing whatever! Free ugrades, expensive ones I DONT CARE. Please and Thank you.:burnout:

87 EFI Mods?

Reply #1 –
A stock or near stock H.O. motor in proper working order is quite streetable IMO.....

You would not have to swap out the ENTIRE motor to have an H.O.
You COULD upgrade to one if you so wanted.....
Read every link on the following page to get you started.  The first one will explain the differences between the standard and H.O. versions of the 5.0 liter motor. 

http://www.coolcats.net/tech/advanced/

In short, the BIGGEST differences will be the cam, injectors, fuel pump & ECU.  There are a myriad of other differences as well.  Upper intake manifold, exhaust manifolds, throttle body, cylinder heads......

In short, you have to ask yourself what you DON'T want to change......It sounds as if you don't want to swap the entire motor and would be against a teardown for a cam swap as well. 

If that is the case I'd recommend something along the lines of a good exhaust (to include headers), an upgrade to the H.O upper intake and throttle body, some 1.7 ratio roller rockers, a rear gear set to your liking (and an upgrade to a trak-lok rear if not so equipped), and lastly a bigger fuel pump.  Different people of course will tell you different things.  Ultimately, it's YOUR car and you will have to live with your decisions.  Hopefully the knowledge base here will steer you toward your goals.

Good Luck!
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

87 EFI Mods?

Reply #2 –
Quote from: V8Demon;307476




In short, you have to ask yourself what you DON'T want to change......It sounds as if you don't want to swap the entire motor and would be against a teardown for a cam swap as well. 

If that is the case I'd recommend something along the lines of a good exhaust (to include headers), an upgrade to the H.O upper intake and throttle body, some 1.7 ratio roller rockers, a rear gear set to your liking (and an upgrade to a trak-lok rear if not so equipped), and lastly a bigger fuel pump.  Different people of course will tell you different things.  Ultimately, it's YOUR car and you will have to live with your decisions.  Hopefully the knowledge base here will steer you toward your goals.

Good Luck!


I ran my T-bird just like that for awhile. It was much more responsive than stock but can't even compare to the engine I have in it now;)
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

87 EFI Mods?

Reply #3 –
Right now my car has the HO upper, TB, 2.25" true duals with high flow cats, K&N air filter with the air box silencer removed, a good tune up with a MSD coil, MSD cap & rotor, autolite plugs and autolite pro series plug wires and 3.45 gears with a track-lok. And it made a huge differance. Future plans are HO swap with GT40 heads, Explorer intake, 19lbs injecters, 65mm TB, mustang short tube headers, mustang H-pipe, and 2.5" tail pipes. Which should be good for an extra 75 to 85 hp. In opinion that is well worth the HO swap. Stock SO motors have 150 HP. The stock HOs have around 200 to 215 HP. Just the stock HO conversion is worth about 50 HP.
88 Cougar LS 5.0 .030 over, ported E7s with GT40 valves & trickflow springs, Proform roller rockers, HO cam, removed air silencer, K&N filter, smog pump delete, 2.25" dual flowmasters, Pacestter H-pipe & headers, HO computer, 65mm TB, Explorer intake, 19# injecters, 3.45s, rebuilt posi, and TCI shift kit.

87 EFI Mods?

Reply #4 –
That was my problem. Not knowing the difference between EFI and HO. Basically I want to boost the cars performance without changing engines or computers. I have a total electronic digital dash and I don't want to screw that up. I just didnt know what HO parts bolt on the EFI motor without modification or messing up the way the computer does its job. Will HO headers bolt to EFI heads or would I have to change heads? I know the firing order is different. Can I still boost timing? I will probably do gears and other stuff later. Is there a Cold Air Kit or will I have to fab one? What kit for Exhaust or is it all have to be custom hung and bent?

87 EFI Mods?

Reply #5 –
Thanks for the link. that should help

87 EFI Mods?

Reply #6 –
The 'Stang headers will bolt onto the E6 (what you, and every NON-HO 5.0 Tbird/Coug have) heads fine.
Pretty much the ONLY difference between SO, and HO engines are the cam, injectors, intake, headers, and of course the EEC.

I dunno about you, but if you could find an HO for 300 bucks or so, swap your Tbird's accessories, change mounts, and get the corresponding EEC....

wouldn't be any less streetable than what it is already.



I have a Sport, I pulled the SO motor, dropped in an HO from an '89, and used an '88 EEC. Runs great.
Instant 75 horsepower gain ;)

I even used the Stang accessories, belt, etc.
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

87 EFI Mods?

Reply #7 –
Quote
I have a total electronic digital dash and I don't want to screw that up.

Swapping to an H.O. computer WILL NOT interfere with the operation of the full electronic instrument cluster.  My car is proof of that as are many others here.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!
 

87 EFI Mods?

Reply #8 –
What is the big deal with changing the EEC if it don't mess with that stuff?

87 EFI Mods?

Reply #9 –
If the stock E6s will work with 86+ Mustang headers. Ill probably do that so I can at least get my exhaust system ran properly in case i do a full conversion or rebuild. I don't want them custom fabing anything because of manifolds. Im doing my exhaust system next weekend. Than, one thing at a time after that. The car is totally bone stock XR7 117,000 miles in case you were wondering, so im just getting started on her. The only thing Ive done is 225/60 BF Goodrich Radial T/A on the factory 10 holes wheels.

87 EFI Mods?

Reply #10 –
You have to do some splicing and moving of wires if you do a Mass Air swap.  If you were to run a speed density type ECU for the H.O. upgrade, it's pretty much plug & play.  You simply re-route the spark plug wires.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

87 EFI Mods?

Reply #11 –
You can run any cold air kit for a 86-88(?) non mass air. I had one but I think they're a waste of money. The stock air box pulls cold air from out of the engine compartment. Just remove the air silencer from inside the fender and get a K&N filter.
88 Cougar LS 5.0 .030 over, ported E7s with GT40 valves & trickflow springs, Proform roller rockers, HO cam, removed air silencer, K&N filter, smog pump delete, 2.25" dual flowmasters, Pacestter H-pipe & headers, HO computer, 65mm TB, Explorer intake, 19# injecters, 3.45s, rebuilt posi, and TCI shift kit.

87 EFI Mods?

Reply #12 –
Quote from: PRO50Mustang1;307634
What is the big deal with changing the EEC if it don't mess with that stuff?


The HO computer is cal'd for the larger 19lb HO injectors and firing order of the HO cam, it's a must change when going HO... The instrument cluster hasn't a clue as to what computer is in the car...