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Messages - Aerocoupe

Electrical Tech / Re: 86-88 ECU Harness Differences?
So the A9L's came in manual cars and the A9P came in automatic cars that were mass air.  The A9P has some additional timing in the lower rpms to help with getting the auto trans moving.  There are also issues with using an automatic car O2 harness with the A9L or a manual trans O2 harness with an A9P (  With the Birds and Cats there were no 5.0 cars factory with a manual transmission so this is why with will work but if you stab an A9L in there you may run the risk of killing the adaptive strategy talked about in the Corral thread I linked above.

Again, I am still curious if the Birds and Cats have the interconnect between the dash harness and the ECU harness.
Engine Tech / Re: Holley Terminator X
I am aware of the stand alone harness like the stinger, holley, and painless but that does not solve the problem for those that want to keep the OEM ECU and harness.  Last time I checked on Ron Francis' website (couple weeks ago) the OEM style injector harness is right at $315 now for a V8 car.  I called them and from what I understand they are not going to build any OEM style harnesses for Mustangs as they cannot locate a couple of the connectors.  Sucks as the stock ECU harness are getting more brittle by the day.  Issues with the OEM harnesses on the Mustangs is they connect to the dash harness but I do not know if that is an issue with the Birds and Cats although I would assume it would be.

I am only going down this rabbit hole as my '93 Coupe needs the ECU harness, injector harness, O2 harness and AC compressor harness.  All of them I bought used when I converted the car from a 4 cylinder and they are not in the best shape.

Electrical Tech / 86-88 ECU Harness Differences?
What are the differences in the ECU harness in the 86, 87, & 88 cars with regards to the V8 multi-port fuel injection?  I know they are all speed density but are there any wiring or connection differences?  I say this as my experience with injection is on Mustangs and there are six different ECU harnesses.  One for the '86 cars, one for the 87-88 cars (88 California cars are the same as the 89 cars due to mass air), one for the 89 cars, one for the 90 cars, one for the 91 to 92.5 cars and then one for the 92.5 to 93 cars.

86 - non mass air, non air bag, and dash harness connection is specific to this year
87 to 88 - non mass air (except California cars), non air bag, and dash harness connection is specific to these years
89 - mass air, non air bag, and dash harness connection is specific to this year
90 - mass air, air bag, and dash harness connection is specific to this year
91 to 92.5 - mass air, air bag, dash harness connection is specific to these years (two plugs), and there is one relay under the MAF and one under the driver seat (fuel pump)
92.5 to 93 - mass air, air bag, dash harness connection is specific to these years (one plug), and there are two relays under the MAF (fuel relay moved)

That was a lot of crap most here could car less about but I have always wondered what the difference is in the V8 injected Birds and Cats.  Again, I am pretty sure that the 86-88 V8 are injected and they are all speed density but do these cars also have a dash harness connector(s) just under the brake booster and by the EEC test ports?  Were any of the late 85 V8 cars injected?
Engine Tech / Re: Holley Terminator X
Which computer harness from Ron Francis were you looking at?  As far as I know he only has the ECU harnesses for turbo coupes not V8 cars.  There is an ECU harness specific to the Pimp for V8 cars but I am pretty sure it is stand alone i.e. does not plug back into the dash harness.
Suspension/Steering / Re: Problems with Cobra brake swap
Other thing I forgot to mention is to make sure you have the caliper bleeder ports at the highest point on the caliper when installed.  You can flip flop the calipers as they do not care which side they mount on until you go and try to bleed them and realize the port is not at the highest point.  With the port flipped you will NEVER get the air out of the caliper.  You can see the bleeder port here in this picture in the correct position.

Suspension/Steering / Re: Problems with Cobra brake swap
So there are a couple things you need to check of which revolves around getting the proper vacuum to the booster.  The valve on your booster where the vacuum line plugs in is a one-way valve so I would start there.  See if the seal is in good shape.  I can pop mine out and you can check the one way action by blowing into the vacuum line connection side and then blowing into the booster side.  If it checks out then inspect the seal and if that is good pop it back in.  Next with the engine off, pump the brakes several times to remove any residual vacuum in the booster.  Now push the brake pedal firmly down and hold pressure on the pedal and start the engine.  You should feel the pedal go down slightly if and when adequate vacuum reaches the booster.  I have always gone off of if the pedal doesn't move at all, comes back at me, or if it goes down over an inch or more there is probably an issue.  I have seen them fail due to brake fluid leaking out of the MC and getting into the booster causing issues.

If you have one install a vacuum gauge in the line at the booster, start the engine and check the available vacuum. Typically you need around 17-22” of vacuum for the booster (and everything else in the car) to work right.  I think you can borrow a gauge from the parts stores if need be.

The other thing I have seen is plumbing the MC incorrectly.  Typically the primary port is the one closest to the booster and should be plumbed to the front  brakes.  This is due to the primary moving more fluid than the secondary which the larger front brakes need.  With a proper functioning MC this could cause the front brakes to not receive the volume or pressure necessary to work 100%.

The only way I know a booster can cause a mushy pedal is for the booster rod not being properly adjusted but it sounds like you have that covered.  Booster is just a multiplier for manual brakes.  To get the power you would need from a manual brake setup you would have to change the pedal ratio i.e. lever arm principle.
Suspension/Steering / Re: Problems with Cobra brake swap
So with all of that anytime I get a mushy brake pedal it is one of two things if there are no leaks.  MC or booster and I would say its most likely the MC but I have had two bad boosters.

The use of the Fox booster with the '94 Cobra MC is not a good choice.  The Fox booster cannot deliver enough boost to compensate for the additional pressure it takes to move the 15/16" bore '94 Cobra MC.  The 93 Cobra MC is a 1" bore, the '95 GT MC is 1-1/16" bore, and a '93 GT MC is 21mm (between 13/16" and 27/64").  As far as I know the 83-88 Birds and Cougars (other than the 87-88 turbo cars) came with a 21mm MC as well.  So with all of that you can see that a stock fox booster was meant to be coupled to a 21mm bore MC.  The 15/16" bore MC is roughtly 13.4% larger in area, the 1" bore MC is roughly 21% larger in area, and the 1-1/16" bore MC is roughly 46.3% larger in area than the stock 21mm unit.  So with that I would suggest not mixing and matching but either run a Cobra MC with a Cobra booster or SN95 GT/V6 Booster with SN95 GT/V6 MC.  The 93 Cobra MC will work just fine with the SN95 GT/V6 booster as many have gone this route so they did not have to change the brake line fittings being the 93' Cobra MC is SAE threads and the SN95 GT/V6 MC is metric.

So with the larger area on the MC bores you can see that they will move more fluid which the larger front Cobra calipers require.  This is also true if you are going from rear drum brakes to calipers.  And the larger area also equals more pedal pressure because you are not changing the pedal ratio hence the need for more boost.

Note - The reason the '93 Cobra runs a 1" MC is the calipers are not the same as the 94+ Cobras.  I know the rears are the Turbo Coupe calipers and the fronts are the same as the GT cars with the exception of the rotors having a taller hat which I believe was done to use an 8.5" wide wheel.  The 93 Cobra R uses the same exact brakes as the 94-95 Cobra.

If you use an SN95 booster you will have to slot the holes on the firewall or get a reman 93 Cobra booster as the mounting studs on it were meant to fit the existing firewall holes.  Massaging the driver side strut tower may be required with the 93 Cobra Booster (seems to be hit and miss) but the SN95 booster will most definitely require it and it can be a bitch with the motor in the car.

So back to your problem.  How did you run the brake lines from your MC to the brake calipers if you no longer have the stock combo valve?  I will wait to go any further until I understand what you did here.
Suspension/Steering / Re: Problems with Cobra brake swap
So here is how both my 93 Coupe was plumbed for the Cobra brakes.  The first round of brakes was a full blown 95 GT brake swap including the ABS.  I pulled everything off of the 95GT that I would need for the swap so the MC & booster cam off the firewall.  Off the front of the car I took the front spindles with hubs, dust shields, rotors and calipers.  Of the back of the car I took everything from the axles out so axles, calipers, rotors, caliper brackets, axle tube brackets, and dust shields.

I used the '95 brake booster out of the car and got a reman MC for a 95GT which has a 15/16 bore.  I gutted the stock Fox combination valve (proportioning / shuttle) on the proportioning side and installed a Wilwood manual proportioning valve to the rear brakes.  Screwing the adjusting knob all the way in (clockwise) produces zero reduction in pressure.  I then backed it out four full turns based on previous experience with other Foxbody Mustangs.   Installed the SN95 spindles, dust shields, new hubs, turned rotors, remaned '99 GT twin piston calipers, new pads, and the flexible lines to the front calipers were swapped to Maximum Motorsport SS braided lines.

The body hard line to rear end line and the hard lines to rear calipers were also swapped out to SS braided lines from Maximum Motorsports.  I pulled the stock Fox axles and all the Fox drum brake stuff and into the metal scrap bin they went along with all of the stock Fox front brake parts.  Installed the SN95 axle brackets, dust shields, axles, caliper brackets, turned rotors, calipers, new pads and connected the MM SS braided lines.

Adjusted the booster brake rod so that it was almost touching the MC plunger and I mean almost.  I have a brake booster rod gauge that I use and suggest you buy one.

Then it was a lot of work plumbing in the ABS and wiring the sensors so we will skip that but it does work and anyone that says they can manually modulate the brakes better is full of crap.

Next I bled the system with a power bleeder.  Again, get one and just be done with it.  They are mandatory on ABS systems and should be on non-ABS systems as gone are the days of pumping the brake pedal.

Dropped it on the ground and about choked myself with the seat belt the first time I hit the brakes.

Note - My Coupe was a 4 cylinder car converted to a V-8 car.  I used an 8.8 out of an '87 GT Mustang and then sourced the body hard line and bracket for the body hard line to rear end soft line off of a salvage yard car.

Engine Tech / Re: Contemplating motor build
So when you take all the parts to a machine shop they will most likely have to resize the rod ends, turn the crank on the rods and mains, and hopefully you are going to have them press in new rod bolts and get new main bolts or studs.  Hopefully they will line hone the block and torque plate when cleaning the cylinders up. The they will assemble the rotating assembly with your new pistons and balance it.

Go look at a 331 or 347 rotating assembly that your stock flex plate or fly wheel will bolt to and tell me how much you are saving by NOT ??? going with a striker short block.

Sure it will not perform like it would with a better cam and induction system but you can always put a cam in it now for the better induction and it will run better than a 0.030” over 302. Save yourself the headache and just stroke it now with a game plan to upgrade the induction later. I did it with my 93 Coupe and do not regret it.

Other Vehicles / Re: '70 F100 Short Bed Styleside
No progress whatsoever. Got the daughter graduated from University of Oklahoma yesterday so that has been our concentration the last couple of years. Hoping I can afford the Coyote and 6R80 next year which will move things along.

Family is good and healthy which is great and hope everyone else here is doing well.