secondaries

[smokinshogun]

so why is it on my 3.2 the secondaries open at 3600 instead of the standard 4000. Just what exactly makes it a better idea for the 3.2's to open earlier? Also with boost are they really unneccasary?

 

[SHOtime2511]

chances are your tach is off.

 

[AREA 91]

3.0 and 3.2 have the same secondary RPM opening. Your tack is off (very common).

 

[doclees]

Ok what does that mean when the tach is off? My 93 kicks in earlier than 4k and my 89 kicks in after 4.3k Can/should it be adjusted?

 

[AREA 91]

No way to adjust the tach's that I know of. I've owned 13 SHO's and most of them are off on the tack reading by a little bit.

 

[smokinshogun]

the service guide says that the 3.2's open at 3600. I can see them open in nuetral too....

here is the page copied
The Air Intake System «Figure 7» is immediately visible upon opening the hood. The primary feature of the air intake system is the dual surge tank and dual runner design «Figure 9». The surge tanks are fed air by a single throttle body that faces toward the left side of the vehicle. Two PCM controlled components are mounted on the throttle body. These are the Idle Air Control (IAC) valve and the Throttle Position (TP) sensor.

Attached to the throttle body are the right and left side surge tank assemblies. These surge tank assemblies run along each bank of cylinders and conduct air to the intake manifold runners. The large size of these surge tanks allows the maximum volume of air required by the engine to be available at any time. In addition, the surge tanks reduce the amount of air turbulence so that a smooth flow and even amount of air is admitted to the IMRC runners.Surge tank assemblies attach to the intake ports (two intake ports per cylinder) with individual IMRC runners «Figure 8». The long, primary IMRC runner comes from the surge tank on the opposite side of the engine. This runner has no obstructions or throttling mechanisms. The short, secondary runner originates from the surge tank on the same side of the engine as the cylinder. The secondary runner contains a butterfly throttle valve plate «Figure 8» which opens, allowing additional air into the cylinders during periods when maximum performance is desired (above 4000 rpm on the 3.0L SHO and above 3600 rpm on the 3.2L SHO). The extra air is channeled through an air horn, reducing turbulence and improving low and mid-range performance.

 

[cowsareholy]

before my lpm my secondaries opend just at 4000rpm on my 3.2 auto after the lpm they open around 3500rpm

 

[JoesSHO]

The secondary runner contains a butterfly throttle valve plate «Figure 8» which opens, allowing additional air into the cylinders during periods when maximum performance is desired (above 4000 rpm on the 3.0L SHO and above 3600 rpm on the 3.2L SHO). The extra air is channeled through an air horn, reducing turbulence and improving low and mid-range performance.

I'm not sure about this, but I do think that the secondaries physically open at the same RPM, but the "desired performance" RPM range of the MXT and ATX are different. The MTX has a "sweet spot" slightly higher than the ATX- it doesn't mean that the secondaries physically open at those RPS's listed.

Anyone?

 

[dantheman68]

mine open at like 4152.34 rpm according to my tach

im just glad they open now... they didnt when i bought the car

 

[armerdan]

Mine open at 4,000 on the dot according to my fluke 88, also my tachometer also appears to agree perfectly with my fluke.
Mine is a 92 MTX with X2J.

 

[Axianator]

the service guide says that the 3.2's open at 3600. I can see them open in nuetral too....

Your manual is incorrect. As Brian (AREA91) pointed out, the secondary runner opening point is essentially the same for all V6 SHO computers (or 3950 RPMs for the '89-'95 3.0L MTX computers and between 3900-3950 RPMs for the '93-'95 3.2L ATX comptuers, depending on throttle position). These values did not change for any of the V6 SHO computers between model years. IOW, an '89 MTX and a '95 MTX will both have the same secondary runner opening point. This same condition applies to the '93-'95 ATX SHO.

If anyone doubts me on these points, please let me know and I will post a snippet of the factory code for your perusal.

 

[smokinshogun]

Ya wish I could prove myself. I found it on the ford service cd when I was reading the description and purpose of the intake. So how do you think they threw this peice of info in there?
Just wanted to know my secondaries before I mess with them. Thanks

 

[jelloslug]

Ya wish I could prove myself. I found it on the ford service cd when I was reading the description and purpose of the intake. So how do you think they threw this peice of info in there?
Just wanted to know my secondaries before I mess with them. Thanks

Well, the Ford service manual did have the coil pack firing order wrong in the '89 manual and I believe it also had a listing for changing the supercharger oil....

 

[dantheman68]

Well, the Ford service manual did have the coil pack firing order wrong in the '89 manual and I believe it also had a listing for changing the supercharger oil....

im pretty sure that was a 3rd party manual....

 

[Off Road SHO]

The butterflies just start to open on the ATX when you rev it up to 4000 in neutral or park but then the PCM commands rev limiting. I don't know what it does to inflict rev limiting but it sounds like spark and fuel cut-off. I hear it all the time on The Other Woman; it sounds like this: verooooooommmmmm ow ow ow ow ow.

Tom

 

[AREA 91]

The butterflies just start to open on the ATX when you rev it up to 4000 in neutral or park but then the PCM commands rev limiting. I don't know what it does to inflict rev limiting but it sounds like spark and fuel cut-off. I hear it all the time on The Other Woman; it sounds like this: verooooooommmmmm ow ow ow ow ow.

Tom

Tom, that's actually a very good description of the sound.

P.S. Quanto Questan on the Eaton???

 

[AREA 91]

Your manual is incorrect. As Brian (AREA91) pointed out, the secondary runner opening point is essentially the same for all V6 SHO computers (or 3950 RPMs for the '89-'95 3.0L MTX computers and between 3900-3950 RPMs for the '93-'95 3.2L ATX comptuers, depending on throttle position). These values did not change for any of the V6 SHO computers between model years. IOW, an '89 MTX and a '95 MTX will both have the same secondary runner opening point. This same condition applies to the '93-'95 ATX SHO.

If anyone doubts me on these points, please let me know and I will post a snippet of the factory code for your perusal.

Remember the old drug comercials on TV?
I learned it by watching you!!!

 

[Off Road SHO]

P.S. Quanto Questan on the Eaton???

Speak English man, or I'll report you to the INS or the Idaho Militia.

Tom

 

[AREA 91]

How much for your SC??? I guess I don't have enough power, yet.

 

[Axianator]

Ya wish I could prove myself. I found it on the ford service cd when I was reading the description and purpose of the intake. So how do you think they threw this peice of info in there?

Just in case I wasn't clear enough with my original reply, let me reiterate: the secondary runner opening point for the '89-'95 V6 SHO is not in doubt, and the runner opening values that I posted above (3950 RPMS for the '89-'95 MTX or 3900-3950 RPMs for the '93-'93 ATX, depending on throttle position) have already been proven accurate. Unfortunately, as Mitchell pointed out, you cannot always accept every single bit of information that you read from Ford service manuals as the gospel truth.

Case in point: if you look at the AX4N Theory and Operation manual, you'll see it clearly states that the AX4N torque converter is capable of locking in second, third, and fourth gears. However, none of the '96-'99 V8 SHO computer programs command any second gear converter lock. In fact, these calibrations don't even contain the necessary code for modifying second gear converter behavior like you would find on other Ford vehicles. Despite these facts, though, we still had a fellow drop by the V8 forum some time ago who swore up and down that, just because his factory service manual said so, the '96-'99 V8 SHO AX4N transmissions could (and did) lock up in second gear, even when I told him that the V8 SHO computers (which control all manner of transmission behavior in the first place) were incapable of commanding second gear converter lock. He was either incapable or unwilling to understand that--just because the transmission was mechanically and/or hydrualically capable of performing a certain function--doesn't mean that the feature is utilized.

Of course, I'm not saying that this is the case here. I'm just using this story to illustrate the point that you can't always trust what you read, even if it comes straight from the "horse's mouth"--or in this case, a Ford technical service manual.

I don't know what it does to inflict rev limiting but it sounds like spark and fuel cut-off.

Like it's counterparts, the soft engine speed limiter that you feel in park or neutral on the Gen 2 ATX is a fuel-based limiter that cuts all fueling to either half or all of the cylinders (depending on vehicle computer calibration) to limit engine speed. The hard rev limiter that you feel at 8,000 RPMs while in a forward gear on the Gen 2 ATX is a fail-safe, spark-based limiter that can cause you to think that you just popped a piston or caused other cylinder damage due to the noticeable alteration in engine behavior that can ensue afterwards.