Mass air conversion question

Topic: Mass air conversion question (Read 10106 times) previous topic - next topic

Mass air conversion question

Reply #15 – October 24, 2014, 06:51:50 PM

I had installed a switch in my vss while I was still on HO SD, I had a Mark VII EEC that had a speed limiter. I'd flip the switch off when it was time to run.

Mass air conversion question

Reply #16 – October 24, 2014, 06:55:52 PM

I'm also happy to report that the wiring install improved the car significantly!!!

I spliced in the wires from that module and to the EEC. Before you sometimes could hardly get around the block without it dying 5 or 6 times, plus you would have to use both feet when coming to a stop, one foot on the brake and the other on the gas when slowing down. I drove the car around for about 30 minutes through town trying to get it to die...it did...but only three times but never when coming to a stop. It was when going about 25 mph or so and I would hit the gas and then let off quickly. I tried that a couple dozen times and only the three times it died and no more "two footing" it to a stop!! I'm happy!

Thanks for the responses!! I appreciate it!

Mass air conversion question

Reply #17 – October 24, 2014, 08:22:31 PM

I've never had any issues like that. Cranky idle on startup in cold weather yes, but after about a minute or so it would go away. I always attributed it to the camshaft. I replaced my IAC and did a base idle reset a few months ago and it's been pretty much flawless. It does get a wee bit cranky when humid. The only time I've ever had the car stall while braking was during an emergency stop situation. near dented the floor board I hammered the brakes so hard. I've never had an issue in drive or had to 2 foot it like you did.

I actually ran out to the car and hooked up the scanner. No code 29......

I think I'm gonna hook up the wires anyhow. While I'm at it maybe I'll finally run the one for the fuel pump secondary circuit.

Quote

I drove the car around for about 30 minutes through town trying to get it to die...it did...but only three times but never when coming to a stop. It was when going about 25 mph or so and I would hit the gas and then let off quickly.

Mine's NEVER done that. How are the baffles in your gas tank? You got any codes still?
What ECU do you run? I'm running a C3W1 that came with the Ford Racing Mass Air Conversion kit. Maybe that one doesn't use VSS? weird.....

My idle is 830 in park 680 in drive right now.....

BTW - I have a full engine harness from an 87 Cougar 5.0 in a box in my garage that came from a car that was totaled out. It's been boxed up for years and in amazing condition. I don't know if it came from a full digi dash or not, but pins #3 and # 6 are empty on that too.

Mass air conversion question

Reply #18 – October 24, 2014, 11:27:55 PM

To add to the craziness:

My 88 Thunderbird had the vss wires in pins 3&6 from the factory. When I did the MAF swap I didn't have to run the wires. The odd thing is that all the wiring colors in my car match the 87 harness. My car was built in September of 87. From what I can tell only the 88 cars had the vss wiring in pins 3&6 from the factory.

Mass air conversion question

Reply #19 – October 25, 2014, 11:05:39 AM

Dave is in Texas. I wanna get a look at his when he gets back.... 87. buttstuffog dash.

Mass air conversion question

Reply #20 – October 25, 2014, 06:24:54 PM

Quote from: V8Demon;439692

I've never had any issues like that. Cranky idle on startup in cold weather yes, but after about a minute or so it would go away. I always attributed it to the camshaft. I replaced my IAC and did a base idle reset a few months ago and it's been pretty much flawless. It does get a wee bit cranky when humid. The only time I've ever had the car stall while braking was during an emergency stop situation. near dented the floor board I hammered the brakes so hard. I've never had an issue in drive or had to 2 foot it like you did.

I actually ran out to the car and hooked up the scanner. No code 29......

I think I'm gonna hook up the wires anyhow. While I'm at it maybe I'll finally run the one for the fuel pump secondary circuit.

Mine's NEVER done that. How are the baffles in your gas tank? You got any codes still?
What ECU do you run? I'm running a C3W1 that came with the Ford Racing Mass Air Conversion kit. Maybe that one doesn't use VSS? weird.....

My idle is 830 in park 680 in drive right now.....

BTW - I have a full engine harness from an 87 Cougar 5.0 in a box in my garage that came from a car that was totaled out. It's been boxed up for years and in amazing condition. I don't know if it came from a full digi dash or not, but pins #3 and # 6 are empty on that too.

The only code I'm pulling now is 95 for the secondary fuel circuit. The ECU is a A9P from an '89GT. The baffles seemed good, I installed a Walbro 400LPH pump and fuel filter probably 3 weeks ago, hopefully everything is good there and must say an easier pump to install then a same year Mustang!!

So, your instructions say nothing for the VSS?? I know the Mustang had the same issue on the SD cars with those PINS and others that you mentioned.

The way the car runs overall is very good, no surging, weird noises, sputtering, hesitation or anything and pulls really hard; It was just that slow cruise and stop. I have my idle at about 900-950ish in park. I could go a bit lower but the cam doesn't seem to like that when coming to a stop, I've read that when the cam gets quite big the IAC has a hard time trying to compensate for it. I've read you can mod the IAC to help with that elsewhere.

Interesting you don't have those PINS either, I was starting to think I had a flukey car or something. What mods do you have on your car what cam do you have?

Mass air conversion question

Reply #21 – October 25, 2014, 07:51:33 PM

Trick flow heads and intake, Ed Curtis custom cam (230 duration at .050" lift max lift .565), 24 pound injectors set to 48 psi, 255 lph pump, 70 mm tb, 73 mm mad, 3.45s, 2800 stall converter, AOD with Silver Fox valve body. Wot shifts are at 6200. This car is the reason I supercharged my Mustang. Will pull on a new 5.0 Mustang without issue.

Mass air conversion question

Reply #22 – October 25, 2014, 08:35:59 PM

Quote from: V8Demon;439736

Trick flow heads and intake, Ed Curtis custom cam (230 duration at .050" lift max lift .565), 24 Pou d injectors set to 48 psi, 255 lph pump, 70 mm tb, 73 mm mad, 3.45s, 2800 stall converter, AOD with Silver Fox valve body. Wot shifts are at 6200. This car is the reason I supercharged my Mustang. Will pull on a new 5.0 Mustang without issue.

I'm assuming you've had the thing tuned? It actually does make use of the extra fuel pressure? (I do have 24's as well)
Just gotta pull the intakes, VC's and front....wouldn't be hard...you keep making me wanna do a cam change LOL. I'd love to get my powerband stretched out that far.
Would be a good easy winter project.

Mass air conversion question

Reply #23 – October 25, 2014, 09:27:10 PM

At stock pressure the duty cycle is Pretty close to maxed. At that pressure the increase is enough to where it stays in the parameters of the EEC-IV processor.

I SHOULD pony up to 30 pounders, but she runs good and strong while being tame when I want -- so long as everything is working.

What cam is in the black car?

Mass air conversion question

Reply #24 – October 26, 2014, 10:04:06 AM

This is why I'm glad I pasted the CL ad into a Word doc.
He said "Trick Flow Cam" but listed .499/.510 for the max lift numbers.

Punched it into google.....http://www.summitracing.com/parts/tfs-51403001 This sounds like the "Stage 1"?
Why the hell does everyone refer to it as the Stage 1 when it seems like the vast majority of vendors and on TF's own site never call it that...? :hick:

Sounds like your cam is similar but with additional lift.
Is there any massive repeating evidence of no PTV clearance with 1.7:1 rockers with that cam and the TW pistons?
I've always been curious why the TW kit comes with 1.6's.

Also...I don't *know* what fuel pump is in there, but it is slightly louder than the one in my '87 Grand Marq and has a very different tone. So someone didn't try to just get away with the stock pump. Though I'd bet the car wouldn't make it past 2500 lol....
I did find a thread where I think TMoss was discussing fuel quantities per hp and yes, to shoot for ~80ish % duty cycle, this top end setup should have 30s. Interesting.

Mass air conversion question

Reply #25 – October 26, 2014, 10:26:09 AM

Trick Flow has 3 cams for Sbf motors designed for the TW heads. Yours is a stage 1. I've had both the stage 1 and mine side by side. The new one has a much more aggressive ramp rate and dwell over the nose.

1.7s with the stage 1 and TW heads should clear no problem.

Mass air conversion question

Reply #26 – October 27, 2014, 04:15:41 PM

Quote from: ZondaC12;439670

I wonder if the dash cluster has its own processor / circuitry necessary to turn the VSS signal into speedometer movement. Might be a really simple execution electrically. I would definitely expect the full digi-dash to have its own CPU.

My black cougar DOES idle high until the moment I come to a stop. Now, I wouldn't want to intentionally cause a stalling like described....but dammit I want to DISconnect this feature on my car...I hate high idling in neutral as I'm coasting...it hides the cam chop . Especially with my cutouts open. When it settles down to 800 RPM or so, it's the perfect shake rattle 'n' roll.

Paul, on your black car are you still running the stock harness? Can you check to see if the wires are in fact not in place at pin #3 and #6? Is your car the full digi dash? Also, what ECU are you running? Lastly, any way you can pull codes and report to us if there is a code 29? It's a continuous memory code, so KOEO should suffice.

I wonder if my car is
A) Haunted
B) Is somehow sending VSS signal to the PCM through other means
C) Has had a glitch in the PCM from day one concerning this.

Mass air conversion question

Reply #27 – October 27, 2014, 05:28:38 PM

Since our cars completely pre-date any kind of automotive networking, you must assume that each module to use a particular sensor is both hardwired to it, and configured to interpret it independently.

Mass air conversion question

Reply #28 – October 27, 2014, 05:37:43 PM

In my particular instance a module was put in place (the PCM) that should use the sensor (VSS) however is APPARENTLY missing the wiring to do so, yet is giving no indication that it is missing the same. IE a diagnostic reveals NOTHING as in for this particular circuit things are working as they should.

I find this extremely difficult to believe with the information I currently know concerning these systems. I'm either missing something that may be in the EVTM, the updated C3W1 I have does not use VSS signal, OR I have had a latent PCM issue for 9 years.....

Mass air conversion question

Reply #29 – October 27, 2014, 06:50:20 PM

Demon - would be more than happy to check these things. I'm feeling like shiznit after a hard day at work...but maybe later I'll feel a little better. I had wanted to do some outside stuff during the light...got out LATE of course, killed that. So as usual the headache will go away an hour before bed and I'll be stir crazy

Remind me about it should I fail to do this tonight or tomorrow.
To my knowledge, the wiring harness is stock. It sure looks like a factory unit and seems to have all of the auxiliary ends over at the ignition coil, etc.