Engine flatlines/jumps

Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

headed to test & tune tonight.

gonna try, new wideband sensor, open loop, more timing. And also try running in OD, i have a hunch this might be the problem. On the freeway is wants to shift to 4th at around 100mph, no matter what springs/weights i change.

hopefully that solves it and i just gotta through down $6k for an 80.
 
It's just a six

It's just a six

Super Member
Re: Engine flatlines/jumps

I worked on a co-workers Mustang 2 1978 ish., it did not run, no oil getting to rocker arms =sludge., anyways

V-6 ran fine flooring it in first & second gear ( 3 spd automatic) when in third gear floored, the tranny would bog the engine down so bad, it would feel like the brakes were on, while keeping it floored, it would downshift back to second gear, start pulling fine, shift into 3rd, then the same thing all over again.

I do not know if that can happen to our 700R4's but just thought I'd share.

.
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

no positive results from the track. I had time for 3 passes.

First pass I left the tune alone and ran 13psi off the wastegate to compare with the run 2 weeks ago. I left it in 3rd gear.

about 3psi launch. 13psi boost
1.71 60ft, 12.10@109mph clean run

2nd run I added 1 deg of timing, same boost and put the shifter in OD. 7psi launch
1.61 60ft, 11.80@111mph clean run, the truck shifted to OD just before the line.

the 3rd run I put good gas in, and put the boost controller on. When I launched the gauge pegged at 30psi+ so I got out of it and idled down the track. I tested the controller at home with my compressor and a pressure gauge and it worked fine. So I gotta figure that out,

Running off the spring at 13psi I am just on the cusp of the 3-4 shiftpoint. So adding boost and timing will push the truck to mph higher and I can test the 3-4 upshift.

So no improvements for right now, With the boost controller working and a hard launch it should take off pretty good. More to come.
 
RealFastV6

RealFastV6

@jb_and_his_coffee
Re: Engine flatlines/jumps

I didn't go back and read the thread so it could be in there earlier - but since you're running a FAST now, how much ignition advance are you commanding (at let's just say 15psi area) ?

ETA: Nevermind I see it now. 17 degrees above 5xxx on a FAST is pretty likely going to give you the results you're seeing. This may not be a popular opinion here and I haven't fully explored this yet (so far my personal data sample is only 1 - I've *heard* about it also from 1 other person), but I literally don't think there's enough inductive delay adjustment in the FAST ECU to work with our distributor to actually deliver the timing that you're setting up in the ECU. I'm going to bet that's also why your boost went nuts on the controller. Retarded timing spools the turbo like woah - but delivers exactly the result you're seeing which is "Hmmm I'm at 18psi but I feel like I'm not going anywhere".

Let's try a couple things...

What's the inductive delay set for in the FAST - and is this an XFI or a Classic FAST?

When you put it in test mode and put a timing light on it and rev it to let's say 3-4000rpm - how much timing retard do you see on the balancer? (I bet a lot.)
 
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Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

inductive delay set at 96. (FAST Classic)

I have revved the engine to 3000 with a light on it, and the timing mark doesn't fall off.

I recently found a vacuum leak, not sure how long it was leaking, but it only leaked under boost. Athough the boost gauge reads solid, and the laptop shows a steady MAP

I am still leaning towards shift point rpms in the transmission. The last pass at the track I put the shifter in 4th, and trapped 115, about 5 higher than the last pass with the same tune.

2gear and 3rd gear are shifting at 400rpm higher than 4th gear. So if I raise my shift weights to 400 over my target in 3rd gear, I think it will work.
 
RealFastV6

RealFastV6

@jb_and_his_coffee
Re: Engine flatlines/jumps

Aeroking said:
inductive delay set at 96. (FAST Classic)

I have revved the engine to 3000 with a light on it, and the timing mark doesn't fall off.
Click to expand...

Of the guys here running BS3 \ FAST, most are upwards of 600+ just to get CLOSE, and I suspect some people are fudging their ignition timing table (either knowingly or unknowingly) to get to where they actually need to be.

Not to belabor the point; but are you sure? I don't recall if the classic fast had a test mode. Did you have to set the entire timing table to X or is there a test mode enable box with a value that you can enter?
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

i set the whole spark table to 30 and ran the RPMs up in neutral with a timing light set to 30adv.
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

I did some street testing yesterday. I run a standalone computer without lockup control, so I lock up manually with a toggle switch wired straight into the solenoid. If I switch it locked under part throttle then roll into it my RPMs match my mph perfect, meaning TCC is locked 0% slip. But if I go WOT, say from a stop, then try to lock it up I have a 5-7% converter slip between the RPM and mph. I ohmed the lockup solenoid at 26ohms, so it should be fine. I'm going to pull the pan and check the position of the TV piston to make sure I get full pressure at 75-80% tps. I still won't turn the boost up cause it will just blow through the converter. I'll update soon.
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

P.s. I changed governor springs and extended my 3rd gear rpms. Just have to
massage it to hit 6000
 
Aeroking

Aeroking

e.i.
Re: Engine flatlines/jumps

I have been running #2 & #5 Blue & Yellow with 5400 rpm shifts. OD at 57mph. Now I am using #4 & #5 Blue & Green 5700 shifts OD at 61mph
 
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