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Diff cams have diff. vac. (which the map sensor reads), I wonder if the Fitech uses like a fixed fuel map, and uses CL comp. to add/rem fuel. The Holley system you can change the fuel map to lower CL comp.
If it was a fixed map, I would imagine getting the cam closes to their expected vac for that cam would put it in range for CL to adjust.
I may be 180 degs off on my thinking, lol
Kirk responded about using it for trans control only, said it wasn't designed to work that way (I figured that) and it might throw codes w/o controlling the engine.
Diff cams have diff. vac. (which the map sensor reads), I wonder if the Fitech uses like a fixed fuel map, and uses CL comp. to add/rem fuel. The Holley system you can change the fuel map to lower CL comp.
If it was a fixed map, I would imagine getting the cam closes to their expected vac for that cam would put it in range for CL to adjust.
I may be 180 degs off on my thinking, lol
Kirk responded about using it for trans control only, said it wasn't designed to work that way (I figured that) and it might throw codes w/o controlling the engine.
Not sure on that but I do know that the FItech system (tuning software on the computer) you can have direct control over the fuel tables. So it would be like tuning in HP tuners where you can put it in open loop and hard tune the VE values. But the FItech basically uses the WB02 to populate the VE table constantly but saves the values like the stock PCM (long term fuel trims) and basically just adjusts them with short term fuel trims after a while. Its constantly learning but I know you have to run it on the street and hit all the load points and RPMs so the system can adjust. So it will take multiple hits on a single VE point (MAP vs RPM) to adjust the fuel trim down and fine tune. Once the value is set (meets the AFR commanded) it saves the LTFT and then it will adjust STFT to meet that commanded AFR constantly. Point being once the LTFT value is saved if something was to happen to the WB02 you would probably still be able to limp it home on the already sorta accurate LFTF saves in the table.
Makes sense about the engine and tranny control. Other standalone kits prob just require a TPS signal and Tach signal along with power and grounds.
Ive read too many things about the MS stuff having issues. Sure they have a ton of features, small package but the PCMs arent even water tight... says alot about the company (which is a computer company not a automotive performance company). Lots of guys chase there tails tuning just to find out a hardware problem in the PCM causing issues. Again this is just me and my opinion and what ive read just randomly searching.
I've found that the folks that have trouble with the prebuilt MS systems, are the same folks that "nothing" works right for.. I hang out with road racers and rally guys mostly and they tend to be more receptive to having to fiddle to get a ECU working,, The MS-Pro I've yet to see a problem with , probably worked on a dozen cars with them. Also a bunch of guys running in cheap classes seem to have decent luck with Microsquirt on small 4 banger NA motors.
The hot ticket in my area used to be the Simple Digital Systems unit, but haven't seen as many of those lately..
120lb injectors? You wanted to run 160lb injectors? That's like 1,600hp on pump gas. Unless your running E85 that's a crazy amount of injector. This is a not a serious all out EFI system. It's a basic intro system that's boost capable. Basically performance on a budget.
120lb injectors? You wanted to run 160lb injectors? That's like 1,600hp on pump gas. Unless your running E85 that's a crazy amount of injector. This is a not a serious all out EFI system. It's a basic intro system that's boost capable. Basically performance on a budget.
Decided to plug in the handheld and go over the tune and setup. This **** is confusing! Even compared to hp tuners lol, going to take some time to get used to.
Where are you finding the MAP vs RPM AFR tables, specifically for boost? A lot of the tables have huge jumps like they tried to simplify the tables for less values. The MAP stuff goes from 90kpa to 120kpa then 150, 200 and 250.
I haven't seen anything about map vs rpm timing retard, map vs rpm VE table or anything.
Just a lot of cam AFR targets etc. I did adjust the spark table which lacks a lot of resolution compared to the stock PCM so i have it set for 18* at 150kpa, 15-16* at 200kpa and 13-14* at 250kpa.
Decided to plug in the handheld and go over the tune and setup. This **** is confusing! Even compared to hp tuners lol, going to take some time to get used to.
Where are you finding the MAP vs RPM AFR tables, specifically for boost? A lot of the tables have huge jumps like they tried to simplify the tables for less values. The MAP stuff goes from 90kpa to 120kpa then 150, 200 and 250.
I haven't seen anything about map vs rpm timing retard, map vs rpm VE table or anything.
Just a lot of cam AFR targets etc. I did adjust the spark table which lacks a lot of resolution compared to the stock PCM so i have it set for 18* at 150kpa, 15-16* at 200kpa and 13-14* at 250kpa.
Presumably it interpolates between the table values...but I don't know that for sure.
Emailed Kirk about MAP values and boost timing and fuel ranges. He's waiting on the software people to get back to him. They use a 3 value MAP system and not just a standard value and scalar.
I have yet to find a thing definitive for timing or fuel in the boost ranges. Like in HP tuners it was a clear VE table and PE AFR in boost etc. I want to make sure I don't go into boost without a solid idea of what it's going to do or I'm commanding.
I also changed directions slightly. Going to pull the supercharger which the other day was only making 9psi at 5500 at WOT. I'm going with a single 76/65 .81 AR turbo and kit. 12psi wastegate spring so hopefully 12-15psi so instead of maxing out my GM 2 BAR MAP I decided to get the 3bar LS9 they recommend and base there kits off of. Now I don't have to mess with the MAP values which is a plus. Bad news is all you guys trying to put LS9 3 bar map sensors in the truck intakes it isn't going to work. The map sensor probe is way to big for the OE hole. You will have to drill out the stock hole to accept the LS9 map but then you won't be able to put a stock truck map back in. Also it uses a through hole mounting so the stock tangs and clip won't hold it either. Not sure how I'm going to get it to work yet.
Attached are the 2 tables I've been focusing on. If you guys have yours setup let me know what u got in these tables as well as the boosted fuel tables.
I actually ended up installing the MAP sensor otherwise I wouldn't have been able to sleep.
Stock truck intake Map hole was too small and the LS9 sensor uses a single oring seal vs a grommet like the LS1. I measured the LS9 map nipple and it was 11.8mm in DIA so the hole had to be at least that big. But the closer the better for sealing. Ended up measuring a 31/64" drill bit and it was 11.87mm so I drilled out the hole in the intake. The sealing area in the intake is only like 3/16" deep and then it's a large open cavity. So to stop the sensor from pushing in too far and past the sealing area I added an oring out of a universal kit to slip tight over the nipple and keep the sensor from going all the at down. That way the sensor sealing ring stays in the area for a tight seal. My intake was broken due to shipping so I jb welded on of the tabs a few months ago. I broke it back off and broke the other tab as the sensor is blocked by them. Some dialectic grease on the oring and pushed it on. It's a very tight seal and would have issues trying to pull it off if I wanted to. But I will fab a bracket to hold it on with one of the mounting bosses near by.
Took 5 min and it gives it an OE look. Side note the LS9 sensor is a very nice solid feeling sensor... looks worth the $32 I paid for it (normally they are $50+) compare to the $50 acdelco LS1 2 bar OE one I have.
Now the sensor will plug right in and shouldn't have to mess wiTh the tune for map values.
Hope this helps some of you guys.
Grey oring is the original and the black at the base is the one I added.
Tabs that I later broke off, hole is enlarged here.
All done! Just need to fab up a Z bracket to keep her down for high boost!
No problem. If you look in the pic I posted of the table it says how to calculate the value but I just don't understand it lol. I tried to back math the 3 bar and it doesn't make sense.
Thanks for chiming in truck Doug. But the 3 bar value they already input is at 5270 with a neg 25 offset. My guess is they they are also including the 3 bar of vacuum? Since the sensors go into -kpa or vacuum as well. So say 26" vacuum to 3 bar or 30psi?
I haven't messed with mine but **** just got real lol. I just received my 76/65 turbo kit. So I could rip everything off and swap this on and then figure out my exhaust and hook up the FItech at all the same time.
I emailed Kirk, it took him a few days to respond.
I asked him about the PWM fuel pump power and he said he wasn't sure and suggested I speak with yet another guy, he would be number four.
I asked if we could chat by phone, he said yes. We set a time.
We spoke today. Unlike his co-workers, he didn't seem to rush me off the phone and he didn't make me feel that he was annoyed by having to answer support questions.
Pump power. He says it's definitely not PWM. Then after some more chatting, he said he was pretty sure it wasn't PWM. But if I was using their fuel tanks, it would need to be PWM. HUH???
Fuel pressure. Does the system need steady state or varying pressure? He said set at 58PSI all the time. Then he started talking about using a fuel pressure regulator with a vacuum line to compensate the pressure (which of course changes the pressure). So, again: HUH???
These are decent systems-and there's certainly people using them without issue. But their support is agonizingly poor.
I agree with the support. If i remember correctly it says to set fuel pressure at 58psi on the regulator as it's an aftermarket setup with there complete kits. Then hook a vacuum line to it like an OE setup. I think it will compensate for the reduction in fuel pressure depending on the amount of vacuum you pull. A boosted setup will increase fuel pressure on a 1:1 scale with boost/psi so essentially it's always reading the same psi (base set at 58, 12psi boost = 70psi fuel pressure but bc 12psi is pushing back on the fuel the engine is still only seeing 58psi. The ECM should still compensate for the fuel pressure drop with vacuum so I wouldn't worry about that.
It can't be a PWM fuel system as they used standard relays in there kits... they would need solid date relays to achieve this. Setup your fuel system so it's 100% all the time and be done with it. Hook the vacuum to the reg or don't it shouldn't matter, just input the correct flow rate at 58psi and be done.
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