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The Turbo 3500 F23 swap (Page 73/80)

ericjon262

AUG 28, 11:47 AM

Fuel economy isn't the sole objective, but anytime I can improve it without sacrificing power is a good thing. I'm not sure what kind of driving you're doing with your car that fuel economy isn't at least a consideration, in drag racing and autoX, if you can run less fuel you can remove some weight, and in road racing you can go further between pits. I'm curious about the delay you speak of in power delivery with speed density. most modern cars run speed density or mass air, and the only time I've felt any delay from one was when a DBW throttle was acting up.

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"I am not what you so glibly call to be a civilized man. I have broken with society for reasons which I alone am able to appreciate. I am therefore not subject to it's stupid laws, and I ask you to never allude to them in my presence again."

I invited Lou Dias to trash me in my own thread, he refused. sorry. if he trashes your thread going after me. I tried.

pmbrunelle

AUG 28, 01:18 PM

quote

Originally posted by ericjon262:
Fuel economy isn't the sole objective, but anytime I can improve it without sacrificing power is a good thing.

I thought about trying lean cruise on my car, NO_X douchebag style, but I decided against it.

I did spend a fair amount of effort making my exhaust pipes; I didn't want to have oxygen in the exhaust gas that could accelerate corrosion of the exhaust pipes. So my highway cruise is at stoichiometric instead.

I don't know if this fear is justified, but I didn't want to take a chance.

ericjon262

AUG 28, 02:51 PM

quote

Originally posted by pmbrunelle:

I thought about trying lean cruise on my car, NO_X douchebag style, but I decided against it.

I did spend a fair amount of effort making my exhaust pipes; I didn't want to have oxygen in the exhaust gas that could accelerate corrosion of the exhaust pipes. So my highway cruise is at stoichiometric instead.

I don't know if this fear is justified, but I didn't want to take a chance.

I wasn't meaning to imply crazy lean cruise AFR's, but that Alpha-N tuning isn't as dynamic as speed density, and therefor your fuel map doesn't account for conditions that would be accounted for in speed density.

25% throttle in third gear will require different amounts of fuel than 25% throttle in in fourth gear at the same engine speed. Speed density will see the difference in manifold pressure and adjust fuel accordingly, whereas, unless my understanding of Alpha-N tuning is wrong, it will see 25% throttle and command the same fuel either way, so it has to be tuned for the most limiting factor, or maximum power.

ericjon262

AUG 30, 02:42 AM

well, this is an interesting saga...

The other day I noticed fuel pressure isn't trending as expected, in the past, I hadn't been watching fuel pressure closely, it had always been more of a go/no-go check instead of a more thorough analysis.

we'll start with the my early findings, I removed the sensing line, set fuel pressure to 43.5 psi, and then went for a drive.

that's with no sensing line hooked up at all... pressure all over the place. with the sensing line hooked up, fuel pressure is almost static. vacuum, boost, doesn't matter, fuel pressure stays in a ~2 PSI band.

at this point, I'm not 100% sure that to think, what I do know for sure though, is that as I try and adjust my fuel pressure regulator, I'm not getting the response I expect. and it's not responding very smoothly per turn of the adjusting screw.

I wanted an excuse to go to Summit racing, the local track requires a helmet at test and tune, and I didn't want to buy one I couldn't try on first, so I decided I'd pick up a new fuel pressure regulator while I was at it. I picked up a new fuel pressure regulator, and when I got home, I started transferring over fittings.

This images is larger than 153600 bytes. Click to view.

the pictures make it pretty hard to see. but there's witness marks on the end of the pipe threads, and on the spring.

the diaphragm also had metal shavings on it.

This images is larger than 153600 bytes. Click to view.

As I removed the fitting, I heard the spring move in the housing, which explains the abrupt adjustments, and pressure not staying stable without the sensing line hooked up. right? I shaved the threads down on the fitting, and put everything back together. As I adjusted fuel pressure, it now closely followed the turns of the adjuster. everything fixed?

well, kinda, but not really.

With the sensing line connected, pressure doesn't change much at all. I decided my next step was to remove the sensing line from the port I was using on the throttle body and try a spot that would be more representative of plenum pressure, I removed the brake booster line, installed a -6 to -4 adapter and connected the FPR to that. problem solved? nope. still flat as a pancake.

there's really not much else that can be going on here, all that's left is the going to the regulator. lets try that! I took the entire line off, gave it a blow, and it's clear as can be... WTF?

I didn't think it would fix anything, but I thought maybe raising fuel pressure higher more towards the middle of the band of the regulator would help? I took it to ~58 PSI, gave it another try.

nothing.

erg. this is quite the odd problem.... I emailed Aeromotive to see if they have any insight, at this point, I'm not sure what's going on, all of the ingredients are there, in the right order. For the time being, I'm going to run "Fixed" fuel pressure, since it's staying very static.

I found a thread on a mustang forum that suggests it could be leaking air past the adjustment screw, I might try and make a cap for the screw that seals it with an O ring or something, there were several commenters who believe this model regulator is junk, if that's the case, it's expensive junk.

https://www.corral.net/thre...-with-boost.1332227/

La fiera

AUG 30, 08:11 PM

quote

Originally posted by ericjon262:
25% throttle in third gear will require different amounts of fuel than 25% throttle in in fourth gear at the same engine speed. Speed density will see the difference in manifold pressure and adjust fuel accordingly, whereas, unless my understanding of Alpha-N tuning is wrong, it will see 25% throttle and command the same fuel either way, so it has to be tuned for the most limiting factor, or maximum power.

Yes, that's why I have the SD map as a secondary fuel load to take care of that. The difference between your engine and mine is that yours is Turbo and mine is not and the deal breaker is the camshaft overlap which is what I use to measure how BIG a camshaft is. The more overlap the less resolution there is in the SD table to tune. My engine idles at 80kpa where yours idles probably at 25kpa. That means you have several rows to adjust where I only have a few. That's the main reason I use Alpha-N as a primary fuel and load table. I could make the timing load to be SD but since I want to throttle steer the car and have instant throttle response, Alpha-N timing load is the way to do it.
I mentioned overlap as a deal breaker, so lets compared your overlap VS mine. Lets assume you have the Racecam from WOT-Tech which is their "biggest cam" and its specs are as follows:
Advertised (.006) Duration= 268/270 (I'll use the intake only because thats the one that counts.)
Duration @ .050= 218/218
Lobe Separation Angle (LSA)= 113
That's all the information I need to see how aggressive and BIG this WOT-Tech camshaft is.
Right away I know its a street cam. Its mayor intensity is 50 and its overlap is 43*.
Since you have a hydraulic cam, for it to be considered aggressive its mayor intensity should be in the low 40's. and when it comes to how BIG the cam is it should be between 60* to 70* of overlap in a V6 60 Degree NA with the right intake and exhaust according to my years of research. There is a specific Duration you can run based in the overlap for maximum power based on the application you want to run.
So basically what you have is a watered down Strip cam with long duration and extended LSA to get the vacuum required to tune on a SD map and that is what camshaft companies do. They want your business and since your cam idles with high vacuum while having "big duration" you are enthused because they sold you the perfect cam. SURE!!
Now lets see about the tuning. At 80kpa at idle the ECM interprets is under heavy load with my cam. Now I have to tell the ECM that 80kpa is Idle. How do I do that? The best way is to command the ECM to use the TPS position as a load and tell it that at 0 TPS is Idle and 100 TPS is WOT. How about if there is a change in load, like going up a steep hill or changing gears? That's where a dual map table comes into play. By adding a SD table as a secondary map to take care of the changes in air densities, gear changes, hill slopes, etc it complements the engine and the tune.
Now lets add another dimension to it. Instead of using the O2 sensor to read the oxygen content and use that information to let the ECM decide how much fuel to add or subtract, lets just tell the ECM that at X TPS I want X fueling and X timing along with X kpa to add X amount of fuel. I'm no longer relying on the O2 oxygen content to adjust the fuel and that is called Closed Loop Tuning. Think about it, If my engine idles at 80kpa it means unburnt gas mixtures ends up in the exhaust and now the ECM sees that and wants to compensate by taking away fuel and leaning the engine. That will result in my engine hunting up and down a couple of thousand RPMs. I can't have that.

fieroguru

AUG 30, 09:22 PM

This graph looks like what you would expect to see when there is a restriction in fuel flow at the entrance of the fuel rail (or anywhere from pump to fuel rail). More fuel used = lower pressure, less fuel used = higher pressure.

This one looks more expected when running a large fuel pump, non-referenced FPR, and everything is properly sized to eliminate any flow restrictions. Fuel pressure remains constant at varying loads.

[This message has been edited by fieroguru (edited 08-30-2022).]

La fiera

AUG 30, 09:28 PM

https://youtu.be/IEoPDi0_oJk

ericjon262

AUG 31, 03:37 AM

I'm happy with my cam, could I have installed a larger cam, sure, I don't particularly want a cam much more aggressive than I have right now. I am installing a bigger cam in my other car, it's not outrageous, but should still make for a fun ride. it's a Grand Am that I'm throwing together with a bunch of stock take off 3500 parts I had laying around, so it have 3500 heads/intakes, a cam, and exhaust manifolds. it'll be interesting to see how it does on the dyno compared to other NA 3400's/3.4's.

quote

Originally posted by fieroguru:

This graph looks like what you would expect to see when there is a restriction in fuel flow at the entrance of the fuel rail (or anywhere from pump to fuel rail). More fuel used = lower pressure, less fuel used = higher pressure.

This one looks more expected when running a large fuel pump, non-referenced FPR, and everything is properly sized to eliminate any flow restrictions. Fuel pressure remains constant at varying loads.

most of the issues in the first graph, I suspect were due to the fitting touching the spring and affecting spring rate.

The second graph is with the sensing line hooked up, so it should be moving up and down quite a bit, but instead is flat as a pancake.

Today I made, what I hope, solves my fuel pressure issues, we'll find out in a few hours. it's based on the idea that the adjuster screw threads are the cause of the leak.

That's a cap that uses the remaining threads of adjusting screw and an O ring to seal the adjusting screw threads.

installed it will look something like this

ericjon262

AUG 31, 11:43 PM

PTT flywheel fits ok, on the LX9 flywheel

This is primarily because the LX9 flexplate has a reinforcement plate on it that spaces the flywheel away from the flexplate. part number 12579453

the PTT flywheel can't stack on a LA1 3400 flywheel

it doesn't have the reinforcing plate. so it doesn't sit flat.

the flexplate is only part of the problem though, it also needs a means to center on the crankshaft. The reinforcing plate on the LX9 flexplate pushes the flywheel out far enough to only contact the flexplate at the mating flange, but it also puts the entire flywheel beyond the register on the end of the crank. so I need to find a way to keep center the flywheel. the fastest, simplest solution is to make a centering ring, much like the hub centric ring used on a wheel, the issue with that, is that can lead to stacked tolerances and sub par alignment.

one of the other ideas was to machine the flexplate side of the flywheel down, but leave a ridge at the ID to register on the crankshaft. the ridge could fit inside the ID of the reinforcing plate, and around the OD of the crankshaft register. I'm not super fond of this idea, unless I could talk PTT into making me a blank flywheel with a thicker mating flange. I'm going to take some more accurate measurements and call to try and talk to one of their engineers and see what they say about that plan.

I'm OK with modification of both the flexplate, and to a degree, the flywheel, the flexplate is a brutally simple part, that doesn't really wear out, the flywheel, requires machine work to fit the engine either way. I do not want to modify a crankshaft in any way to fit this. at this point, a centric ring looks preferred, the cut required to make the reverse register on the flywheel would be pretty meaty, to go the full depth of the reinforcement plate, the cut would be about ~2.5mm, on a flange that's only ~7.25mm to begin with.

anyone have another idea?

Edit: Will mentioned an idea to me that I had already dismissed, but on second thought, it may be worth exploring, if I make a part that going into the crank where a pilot bearing would go, I could extend the length of the register as long as I need. My biggest concern about this was input shaft clearance, I'm going to take more measurements when I get home. if I do that, I wouldn't machine the pilot bore full depth, I would make it slightly short, in order to make sure the register extension is captured and can't walk out.

also, fwiw, PTT flywheel, resting on a LX9 flexplate, has a stack height of about 1.05"

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back to the fuel pressure shenanigans...

I made another interesting series of discoveries today...

My BOV and my FPR use the same manifold source, which tee's off the side of the throttle body. I disconnected this tee, connected a mity vac to the tee, and started pumping, vacuum dissipated almost instantly. so I split off the FPR, tested it seperate, with my new fancy cap installed, wouldn't you guess, it holds vacuum no problem. Unscrew the cap, and it instantly dissipates. well, I fixed one issue. I triggered the fuel pump output in test mode, and vacuumed it down, now everything appears to be in working order...

now, connecting to the other side of the line, going to the BOV, still, nothing... I mean absolutely nothing. as fast as I can pump, it's not holding at all, piston doesn't move either...

I took the BOV off, and disassembled it. the spray gun needle is not part of the assembly.

notice anything here?

how about in here?

well, without any kind of seal, I would imagine it wouldn't seal worth a **** . I'm not real happy about that finding, it's a legit Turbosmart BOV, not some no name china crap, I'd prefer not to rework the charge pipe for another BOV, but I'm not sure this flange is shared by a diaphragm style BOV. For now, I think my smartest move, will be to reinstall the existing BOV, it does relieve air like it should, but I'm not cool with a boost/vacuum leak just because something is a poor design. but because the BOV leaks, I can't have it, and the FPR tied to the same source, my plenum has a cast boss next to the brake booster line, I'll pull the plenum, drill and tap the boss, and take the FPR off of that, then, I'll leave the BOV attached to the TB. When I pull it apart to fix the cam bearing wear, I'll cut the BOV flange out, and weld in a diaphragm style valve to replace this piston style.

------------------
"I am not what you so glibly call to be a civilized man. I have broken with society for reasons which I alone am able to appreciate. I am therefore not subject to it's stupid laws, and I ask you to never allude to them in my presence again."

I invited Lou Dias to trash me in my own thread, he refused. sorry. if he trashes your thread going after me. I tried.

[This message has been edited by ericjon262 (edited 09-01-2022).]

zkhennings

SEP 01, 02:31 PM

For a sanity check you could hook up a vacuum bleeder or a bike pump to your fuel pressure regulator and see if you can get the fuel pressure to increase or decrease. If it is not changing then the FPR is the problem, if it does change then something is going on with your reference line. I know you said it was not clogged but this could help you further isolate your issues.