I'm Back Into The Mustang Scene With A Rescue Project.

JeffC

Member
May 31, 2017
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Hi everyone...
I'm new to the mustang forums. Although I've been doing a lot of forum reading for the last few weeks.

I'm back into the 5.0 scene after a couple decades away.
I figured I'd go the project route on my welcome back, and it's being a real burner.

I purchased a 90 LX notch, 4cyl conversion, with 91 gt drive train. The owners plan was to turn it into a drag car. It was done not so well. My plan was to salvage this notch and make it into a thing of beauty.
I only chose this route because I love the fox body notch stangs. That was what I owned previously. And this fox body has a frame and body in very good shape for the year.

Specifics:
The engine has all the vacuum, ac, smog etc deleted from it. The egr is still electrically connected but the vac port isn't.
It has BBK headers and the SLP exhaust system.

I upgraded with the ac delete bracket to move the ps pump, installed a shorter belt, new cap, rotor, coil, new battery cables.
The plugs and wires look new. I haven't inspected them yet.

Here's my first issue:
The car idles rough and runs rich. Even after what I have replaced.

I've researched the egr and delete possibilities. There are so many yes's and no's on this topic.

Should I purchase the delete kits and go that route?
Should I turn this into a carburetor engine?
Should I try to locate all the missing vac components and re-install?

Is there a best / better solution that won't break the bank?

I'd like it running well before I go and tackle the engine upgrades and transmission issues it has.
 
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Welcome to Stangnet.

I'm going to move your thread over to our fox body general talk section. You'll get lots of help there.

Include some pictures for us, that'll help us to help you as well.

Good to have you with us.
 
It's simple really..

You've gotta make an either/or choice.

Either you reinstall all of the necessary sensors that the factory ECU needs, including the catalytic converters, or you'll have a difficult time getting the engine to idle properly, and w/o polluting up the place. The engine needs so many things for the factory ECU to do it's job,..taking away part of them is like me duct taping your arms to your body and then telling you to lift something up.


Or..

You can put either an aftermarket ECU like a MS, or a Carburetor that doesn't need the deleted sensors to idle properly.
 
Take an inventory of missing/cobbled up sensors and wiring, look to see what computer it has, try to run the codes, and as I also suggest, check the grounds to make sure all of them are present and have good contact.
 
It won't be a minute before Jrichker puts his 3 page "Build goal" thread on here.. and others are gonna ask as well.

Is this a street car?
Why would you delete the AC if that's the design intent?
Nothing in the existing smog circuit/EGR robs the engine of any significant power,...If this is a street car, and by that I mean it will be primarily driven, w/ occasional trips to a drag strip, you'll be better off doing what you can to completely restore the engine w/ all of the factory vacuum and egr in place if idle quality, good power, and low emissions are part of that goal.
 
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It won't be a minute before Jrichker puts his 3 page "Build goal" thread on here.. and others are gonna ask as well.

Is this a street car?
Why would you delete the AC if that's the design intent?
Nothing in the existing smog circuit/EGR robs the engine of any significant power,...If this is a street car, and by that I mean it will be primarily driven, w/ occasional trips to a drag strip, you'll be better off doing what you can to completely restore the engine w/ all of the factory vacuum and egr in place if idle quality, good power, and low emissions are part of that goal.

I'm running a little slow this morning....
Step 1 - Dump the codes...
Dump codes sticky.
Look at the top of the 5.0 Tech forum where the sticky threads are posted. One of them is how to dump the computer codes. http://www.stangnet.com/mustang-for...codes-from-eec4-in-86-95-5-0-mustangs.889006/ I highly suggest that you read it and follow the instructions to dump the codes.

Step 2 fix the codes - Post them here and I can give you 5.0 fox Mustang specific fixes.

Step 3 once you have the codes fixed and the car running good, decide what you hand to do with the car...

noobie-help.png

Far too many people put a dab of this and a dollop of that, and then wonder why the car doesn't run worth beans. Then they think off the shelf computer chips will fix their mismatched parts problem. It won't

You have to have a plan for what kind of performance you want: Hot street. Street/Strip, Pure strip, Autocross or Road course. Each one requires a different strategy and a different set of components.. Mismatch the components and you’ll have a car that falls flat on its face when you demand performance.

Everyone thinks HP! HP! HP! and thinks that peak HP is what they need. Peak HP is great for a drag strip car when it has the proper gears and tires to get the car up into the high RPM range where it develops that high peak HP near the finish line. On a street car, that strategy will have Honda Accords outrunning you, because you will never get the engine RPMs high enough without running over everything in your path.

Here’ the strategy: Always remember that there are some tradeoffs in any engine combination. Most of us don’t have enough money to “have it all” as if it was possible by some masterful combination of parts and tuning.

The following recommendations are for 5 Speed Manual transmission cars without NO2 or pressurized induction, stock short block.
1.) Hot street: Broad flat torque curve, high velocity airflow in the intake and heads for best throttle response. Gears suitable for reasonable gas mileage and long road trips without excessive engine RPMs. Stand on the gas pedal from a rolling start to squeeze into that gap in traffic in front of you, and it jumps quick and hard to get you there. Max RPM’s are 5200-5500 RPM for best power. Lopey cams may sound cool, but run poorly in a low RPM street environment.
Use stock cam, stock, GT40 or mildly ported stock heads, Cobra or Explorer/GT40 intake, advanced timing, stock 19 lb injectors, stock fuel pump. Use some good 1.6 or 1.7 ratio roller rockers for extra punch. Use a King Cobra clutch, with stock iron or steel billet flywheel. MAF cars can use a 65 MM TB from the Explorer intake manifold and a 70MM MAF from a 94-95 Mustang. Drive train: 3:55 gears with soft tread compound tires. Use some Ford Racing unequal length headers, stock 2 1/4” cat pipe and some mufflers that don’t drone or get too much attention from the law enforcement or neighbors. The stock computer will handle all this with no problems and doesn’t need any help in 90% of the cases. No skinny or grossly undersize tires for the front: remember you still have to stop quickly in traffic. Make sure all the rubber bushings in the front and rear suspensions are in first class shape. Leave the emissions equipment intact and working. Removing or disabling it won’t get you any more HP or performance. Do not convert to carb or remove A/C: either one will reduce the resale value. Carb conversions cannot be titled for street use or get tags in some places. They definitely won’t pass smog inspections.

Street/strip: A little more slope to the torque curve with a gently sloping peak. Use slightly larger port volumes on intake and heads for more peak HP. Uses 3.55 or 3.73 gears to get the RPM’s up into a higher range quicker. Be prepared to sacrifice some low RPM throttle response in exchange for high RPM power. This by necessity will be a Mass Air or Mass Air conversion on 86-88 5.0 Mustangs, since stock speed density will not run well with the changes in engine airflow. Don’t get too crazy on any one engine part since you still have to drive the car on the street, and a mismatch can make street driving miserable.
Use stock or mild aftermarket cam, Ported GT 40, or 165-180 CC port volume aftermarket aluminum heads. Use a Trick Flow, Edelbrock Performer or equal intake manifold. Take a 73 MM aftermarket MAF calibrated for 24 lb injectors, and 24 lb injectors, 155 LPH fuel pump, Kirban adjustable fuel pressure regulator. Be prepared to shell out some $$$ for a custom burned chip using data gathered from a dyno run. Mass market chips will not get the job done. Use some Ford Racing unequal length headers, aftermarket 2 1/2” cat pipe and some mufflers that don’t drone or get too much attention from the law enforcement or neighbors. Drivetrain: expect the stock T5 to fail, so save your money for a super duty 5 speed trans. Tremec 3550, TKO 500 & TKO 600 are the best choices. Different gears in a stock T5 case work for some, but there is only so much power you can pass through a T5 in race mode before it breaks, even with stronger gears. Next are the Chassis mods: full length subframe connectors, different springs, different shocks, aftermarket lower and upper control arms with rubber or urethane bushings. Buy all the parts from someplace like Maximum Motorsports, Griggs or Steeda as a kit so that you know that all the parts fit and don’t argue with each other. Carry spare tires and wheels for the drag strip: skinnys for the front and drag radials for the rear. No skinnys for street driving! Over 85% of the breaking power is generated by the front tires, so skinnys won’t do the job in a panic stop situation. Disconnect the front anti-roll bar at the strip; reconnect it before you drive home. Leave the emissions equipment intact and working. Removing or disabling it won’t get you any more HP or performance. Do not convert to carb or remove A/C: either one will reduce the resale value. Carb conversions cannot be titled for street use or get tags in some places. They definitely won’t pass smog inspections.

Strip only: High RPM, High flow heads (185-215 CC port volume), wild cam, high flow intake manifold, 70 MM or larger TB, 80 MM or lager MAF, strip everything out of the car that doesn’t make it go faster. Carbs are OK if that’s what you want, but remember that as the temp/humidity/ barometric pressure/altitude changes, you have to re-jet and readjust the carb. EFI eliminates most of that with its built in compensation or you can tune of the fly with a high end Motes or Tweecer system combined with a wide band air/fuel ratio meter. Use custom headers, dumps and minimal mufflers. How fast you can go on 5 liters is a function of the skill level of the driver/mechanic and the size of your wallet.

TRAILER the car to the race track since it won’t be legal to drive it on the street. Drag slicks in the rear, skinnys up front, use 3.73 or bigger gears (4.xx) in the rear axle. Since you won’t be driving on long trips, the big gears with work with the high RPM power curve to get the best results. Drivetrain: TKO 500 & TKO 600 are the best choices. Different gears in a stock T5 case work for some, but there is only so much power you can pass through a T5 in race mode before it breaks, even with stronger gears. Next are the Chassis mods: full length subframe connectors, different springs, different shocks, aftermarket lower and upper control arms with rubber or urethane bushings. Buy all the parts from someplace like Maximum Motorsports, Griggs or Steeda as a kit so that you know that all the parts fit and don’t argue with each other. Remove the front sway bar, put an airbag in the rear spring of the side that spins the tire the most. Plan on a roll cage if you are truly serious about going fast: most strips will require it once you get to a certain ET range.

Autocross is a combination of Hot street engine and street strip chassis prep. The engine must accelerate quickly from low RPM and needs a broad, flat torque curve. Next are the Chassis mods: full length subframe connectors, different springs, different shocks, aftermarket lower and upper control arms with rubber or urethane bushings. Buy all the parts from someplace like Maximum Motorsports, Griggs or Steeda as a kit so that you know that all the parts fit and don’t argue with each other. Most of the time you’ll never hit third gear, so some 3.73 or bigger gears (4.xx) may help a lot. You’ll have to spend some more money on brakes since it kills brakes quickly. Rear disks, larger rotors up front, stainless steel brake lines, different brake pads. A 87-88 T Bird Turbo Coupe or SN 95 rear axle will be your best bet. Autocross will severely strain 1st & 2nd gears, so your T5 may take a premature dump. Save your money for a super duty 5 speed trans. Tremec 3550, TKO 500 & TKO 600 are the best choices.

All out road race is the most difficult of all: an engine that will run at high rpm hour after hour and never fail, yet pull hard out of the hairpin turns that will require a lot of torque at lower RPMs. In my opinion, guys that can successfully build a winning road race engine are the cream of the crop. Top this off with a chassis built for strip only duty, but with changes to the settings of springs, tires, roll bars brakes and shocks. It’s a whole other world of racing.
You’ll have to spend lots more money on brakes since it kills brakes quickly. Rear disks, larger rotors up front, stainless steel brake lines, different brake pads. Air ducting to cool the brake rotors will be a must. The brake rotors of cars on a high speed road course glow red after several hard laps of racing. Drivetrain: TKO 500 & TKO 600, and T56 close ratio are the best transmission choices.
 
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Thanks for all the responses.

My plan is to make this into a high performance street car only. No track.
Not necessarily a DD, as I have another vehicle.

I haven't even made a full list of what parts I want to install, as I'm just trying to get it running correctly and keep the thing charged.
The interior needs to be replaced.
The AOD transmission wasn't set up properly and needs work.
The rear clunks.
I want to keep it an AOD with a shift kit.
Overhaul the engine with cam etc.

I don't have a good history on the car from the previous owner. He wasn't too informative or had a lot of knowledge of everything. His plan was to make this a drag car.
Everything looks original, outside of the cold air intake.
Except for the IAC, cap and rotor, solenoid I put on.
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It's a 90 4cyl notch conversion with a 91GT drive train.
The "mechanics" supposedly used the 91 harnesses. They all seem to be there. But I haven't gone through everything yet.

The previous owner deleted the AC, smog pump and all emissions, from what I can tell.

I've started going through my 90 mustang mechanics manual to try and get somewhat of a handle on what's there and what's missing.

Charging issue: I've replaced the battery cables and solenoid.
I tested the battery and it's low.
The alternator was tested as a 5 out of 6 on my meter.


Here are some pics.
 
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That car is a 5 out of 10 in my opinion, looks like a good save.
Keep us posted.

Thanks!
It definitely needs some TLC.
The car only has 41k on it.
If sat for a few years after the original 4cyl owner got a DWI.

I'm hoping to get it done in a similar fashion as the "nasty notch" was done.
 
i'm always leery about 4cyl conversions because you are relying on someone else to have done the conversion correctly. There are so many vaiables to consider did they address- wiring, braking, suspension, brakes, transmission, harnesses, etc. that unless I know the guy or he can document what has been done, I won't consider it.

The car looks fairly clean and straight, but you are going to find out probably that things need to be fixed to bring it up to just being a normal 8cyl car before you can think about modifying it.

I would go from bumper to bumper and address anything that needs repaired as far as maintenence first, then also look at items such as improving the suspension and braking first.
 
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As mikestang63 has said, there is a lot of territory on a 4 cylinder to V8 conversion that can be done incorrectly or poorly. Brakes, suspension, fuel system are all different between 4 cylinder and V8 cars. The 4 cylinder and V8 cars are really different. Just about the only common parts are the interior, body shell itself and rear body electrical harness.


Here's some help for you to find out what's right and what's wrong. Print it off and take your time reading and digesting it. Then take the printed copy and start comparing it with what you actually find on the car. That will go a long way towards getting it done the right way.

https://www.stangnet.com/mustang-fo...ctly-do-i-need-to-convert-mine-to-5-0.516785/
 
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When I bought the car it had Weld drag wheels on it. The car bounced when driven. I assumed it was out of balance wheels. So I bought the current set on there now. I was correct. Out of balance.

I knew I was going to have to spend a lot of time on this, making sure everything was / is done correctly. I've been reading about the conversions. The do's and don't's.
I did a basic bumper to bumper check, over and under one evening.
Here's what I found:

The front frame bumper was removed.
Front nose piece is attached by 4 screws.
Headlights are missing rubber seals. Broken plastic. (Purchased new one piece clear)
The full suspension up front needs to be replaced. It's all original. Tie rods etc.
Front brakes are original.
Steering is original.
No leaks anywhere. (Shocking)
Has tranny V8 cross member.
Speedometer not hooked up to tranny.
V8 gas lines were run.
GT exhaust with SLP mufflers.
BBK headers
All fluids were clean. Recently replaced.
The master cylinder appears to be a V8.
Drive shaft and 8.8 rear ended look and operate rough.
The 4cyl AT shifter isn't hooked up properly. The car only operates all gears through the D option.
Blinkers and dash lights don't work. (Blinkers fixed outside)
Tach gauge is still on 4cyl.
Oil pressure gauge is reading real low. Only increases a small amount when revving. (?) incorrectly wired pressure sending unit?
Rear shocks were replaced with ones for a drag wheel set up.
Rear upper and lowers need to be replaced. A arms too.
Rear brakes need replacing.
All window and door seals need replacing.
Door pins / hardware need replacing.
Power locks don't work.
No cruise.
Horn works.
Airbag light is on. (Know that's because the front internal bumper is gone and there's nothing plugged into the connector.
Torque boxes are 4cyl and will need upgrading. No damage here.
EEC was replaced. I have to locate the box for that info.

I think that's it for now.

I've been told by a couple mustang guys to find a wrecked donor car and compare. I've been looking.
 
I know that some of the instrument clusters are V8/year specific, At least thats my understanding, if your's is not compatible you may need to change it or at least some parts of it, someone will chime in to verify, there is also a thread here dealing with a 4 to 8 swap that may help.
 
Ok... finally had some time to do testing.
I used my ford OBD1 code reader and ran a koeo test.
The results were 67, 81, 82, 85, 87, 84.

It wouldn't let me run the koer test. Although, when I engaged the reader on test, the car accelerated quickly then dropped down in idle. No codes ever appeared on the screen. It sat at 000. No flashing square.
I ran the test 3 times. Same result.

I've read all the code info and will dig into it.
I know the emission codes are due to the lack of the emission components.
 
I did not have the car in neutral.
I guess I missed that part in the instructions for an AT.

No ac on this car.

I'll run it again tomorrow in neutral if that's what needs to be done.
 
Ok... ran the koeo test again. This time in neutral.
Same codes. 67, 81, 82, 85, 87, 84.

I'm wondering if the 67 code is appearing because the transmission isn't adjusted properly.
This car has a park, neutral and all 3 speeds are used in the D position.
OD and 1 do not work.