[FrankieT/A]

After two years of my self learning through trial & error, forums, google searching and of course the inept, improperly trained FITech tech support team. I have a manually shifted car and when using the A/C the car would stall every time I came to a stop. Without the A/C the car ran fine.

When going in to the A/C control on the hand held nothing is adjustable with the joy stick. Silly me I assumed none of this stuff was adjustable, turns out if you go into "Edit" you can change stuff. I found this out inadvertently. I reloaded factory settings, started from scratch and started adjusting in A/C control and fixed all my woes. Couple other adjusts from there and voila! The car runs great all around including a fantastic idle.

Bottom line... FITech needs better training in tech support and better definitions of hand held nomenclature. The pure definition is not enough. A little explanation or example of what each thing does. "Going in this direction does this or going in that direction does that" that sort of thing. Also, the definitions are not complete, There are a bunch of menus that aren't even mentioned. I mean WTF?

[Formulajones]

Holley is the same way. Their tech sucks. Luckily they have a forum with some helpful people on it, but even that still doesn't help you navigate through things or understand how some tables work and affect other tables.

Unfortunately the instruction tuning booklet that the forum constantly refers you to isn't provided with the Holley EFI kits either, and they act like you should have read all this stuff already, lol. Well maybe if it came with the kit. Pffff You'd think when you pay $2000 for a Holley Super Sniper Stealth 8 Injector unit, they could provide the tuning booklet.

So there is a ton of online searching and reading that has to be done and even then you probably won't find everything you're looking for unless someone directs you to it. So yeah, I understand your frustration.

It's been a new learning curve for me as well. Luckily I've had a bunch of experience tuning with HP tuners on LS engines back in the 90's and early 2000's so some of the Holley stuff already made sense. Actually a lot of the Holley stuff is dummied down compared to the OEM factory tuning software making some of it a little easier to understand.

[FrankieT/A]

Good to know...My next move was to go to the Pro Flo 4 being that is port injected and eliminates manifold wetting. I owned a car shop back in the day so not everything is foreign to me. Right now I'm pretty happy with way it is performing. The stalling was driving me bezerk. A little tweaking here and there and ill be good.

[Formulajones]

Originally Posted by FrankieT/A

Good to know...My next move was to go to the Pro Flo 4 being that is port injected and eliminates manifold wetting. I owned a car shop back in the day so not everything is foreign to me. Right now I'm pretty happy with way it is performing. The stalling was driving me bezerk. A little tweaking here and there and ill be good.

I kind of like the manifold wetting, acts as a cooling charge and tends to make a little more power on the dyno but that's neither here nor there for most people. Port injection is pretty sweet though. Mike, a member here just converted his 455 to Edelbrock port injection with a turbo he custom made. Used an LS crank trigger and stuff with coil per cylinder. I was just looking at it this weekend, it's a very nice setup.

I did 2 Holley EFI Sniper installs on our cars here recently, and didn't have stalling issues with either, but the cold and hot starts have been a real chore to nail down. I have one fixed and working fine, the other one, dad's GTO, the cold starts are better, but hot starts are still hit and miss.. It's been a real pain. I'm starting to believe the IAC isn't big enough for his 571ci engine. I'm trying to figure tuning ways around it. But idle and running has been really good.

[FrankieT/A]

Makes sense on the IAC for big cubes. My cold start is pretty good. Hot start like you hit and miss. That's one of the things I need to get to. Drivability was my first concern. Now that I have that pretty much under control I can start fine tuning. I would love to have coil on plug for a Pontiac. This particular car I'm working is an LS. The motor I took out was a 325 CFM E headed 455 .030 with a road paver. The LS likes a lot more timing and less fuel than the 455, but the car rips.

[Formulajones]

I like the LS stuff. They make great power for their size. Won't find much love on this site for them but those that have owned them know. I had 4 of them over the years and did a couple of retro swaps as well, it's just a fantastic engine, so I'm with ya.

You made me feel a little better with your hot start hit and miss issues. LOL I thought I was the only one.

[FrankieT/A]

Absolutely NO love on this site, lol. That's why I haven't changed my signature.

[Formulajones]

LOL It's all good with me

[JLMounce]

Manual shift cars will typically need changes to decel fuel cut off, both for amp setting at cut and return and may also need some adjustment to loop rate down.

When the clutch is depressed, load bottoms out and the system will tend to go into fuel cut too early and bring the fuel back in too late. The loop rate down might be an issue in your circumstances as the AC is likely increasing the deceleration rate of the engine, also cutting fuel.

Sounds like your AC controls have this smoothed out, but I would run a log to see what your MAP does and how quickly the engine decelerates with clutch in coming to a stop with both AC on and off. Adjust the parameters for dfco and loop rate accordingly.

[Formulajones]

Originally Posted by JLMounce

Manual shift cars will typically need changes to decel fuel cut off, both for amp setting at cut and return and may also need some adjustment to loop rate down.

When the clutch is depressed, load bottoms out and the system will tend to go into fuel cut too early and bring the fuel back in too late. The loop rate down might be an issue in your circumstances as the AC is likely increasing the deceleration rate of the engine, also cutting fuel.

Sounds like your AC controls have this smoothed out, but I would run a log to see what your MAP does and how quickly the engine decelerates with clutch in coming to a stop with both AC on and off. Adjust the parameters for dfco and loop rate accordingly.

Don't you have the option on the Fi-Tech to turn on or off the fuel cut off?

I know on the Holley system you can turn that on and off. In fact on the base tunes that are configured to start with, the fuel cut off is turned off already. I've never turned it on.

[JLMounce]

Originally Posted by Formulajones

Don't you have the option on the Fi-Tech to turn on or off the fuel cut off?

I know on the Holley system you can turn that on and off. In fact on the base tunes that are configured to start with, the fuel cut off is turned off already. I've never turned it on.

Yes it can be completely disabled if you wanted to do so.

[Formulajones]

Originally Posted by JLMounce

Yes it can be completely disabled if you wanted to do so.

Ah okay. That seems like the thing to do if it's troublesome. I used to have that enabled on a couple of LS tunes and all it really did was cause pop and cackle out the exhaust when I was coasting down the mountain

I simply leave it disabled on the Holley Sniper, figure it's just another tuning variable that I don't need in the mix right now. Maybe when I'm happy with the tune nailed down I'll play with it at some point.

[72projectbird]

Originally Posted by Formulajones

I like the LS stuff. They make great power for their size. Won't find much love on this site for them but those that have owned them know. I had 4 of them over the years and did a couple of retro swaps as well, it's just a fantastic engine, so I'm with ya.

You made me feel a little better with your hot start hit and miss issues. LOL I thought I was the only one.

The hate they recieve makes it more fun! lol

[Formulajones]

Originally Posted by 72projectbird

The hate they recieve makes it more fun! lol

This guy was hating my LS swapped Blazer

https://youtu.be/msgSc3S-yHA

.......

[1980 TA]

Is the AC control a new feature in the FITECH or did I miss something on my install? I'd love to be able to bump the rpms a bit when the AC is on.

[JLMounce]

I believe that's a Power Adder model only option. However a lot of the standard non-power-adder models have the software buried in them still. Check the Pro-Tuning section of the hand-held. You may find it there.

[1980 TA]

Thanks. I looked at my wiring diagram and there is no wire to use as a switch in my harness.

[FrankieT/A]

The A/C signal wire is in the plug with Fan 2. And yes it is a power adder thing. The messed up part is you can't adjust the A/C stuff with the joystick, its only adjustable through the edit feature.

[HWYSTR455]

Originally Posted by Formulajones

I kind of like the manifold wetting, acts as a cooling charge and tends to make a little more power on the dyno but that's neither here nor there for most people. Port injection is pretty sweet though. Mike, a member here just converted his 455 to Edelbrock port injection with a turbo he custom made. Used an LS crank trigger and stuff with coil per cylinder. I was just looking at it this weekend, it's a very nice setup.

I did 2 Holley EFI Sniper installs on our cars here recently, and didn't have stalling issues with either, but the cold and hot starts have been a real chore to nail down. I have one fixed and working fine, the other one, dad's GTO, the cold starts are better, but hot starts are still hit and miss.. It's been a real pain. I'm starting to believe the IAC isn't big enough for his 571ci engine. I'm trying to figure tuning ways around it. But idle and running has been really good.

One thing that helps is cracking the throttle blades a more, especially on larger displacement engine, that way the IAC doesn't have to 'work' as hard. Target idle compensation for IAC is 5-7%, but it will creep some after full heat soak.

Obviously, you need to do a TPS autoset after any throttle blade adjustment.

.


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[Formulajones]

Originally Posted by HWYSTR455

One thing that helps is cracking the throttle blades a more, especially on larger displacement engine, that way the IAC doesn't have to 'work' as hard. Target idle compensation for IAC is 5-7%, but it will creep some after full heat soak.

Obviously, you need to do a TPS autoset after any throttle blade adjustment.

.


.

Yeah, basically what I've had to do for now to sort of fudge it, is to set the idle screw while in neutral until I have zero IAC, so that when it's in gear, it gives the IAC more room to open and maintain the idle. There are instances where it would sometimes just peg the IAC in gear and then slowly idle down and die.

It's been a fine line of adjustment that has been a real pain on dad's engine. On my engine (110 cubes smaller) it was a piece of cake.
I really think the IAC just needs to be bigger and I'm almost certain a couple of small holes in the throttle blades would help but mention that on the holley forum and they have a fit LOL.
For what it's worth, the HP 950 that was on the engine came out of the box from Holley with all 4 throttle blades with holes just for this purpose and that thing would idle at 750 rpm all day. This engine really likes a lot of idle air, and fuel.