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So.. I've got closed loop idle configured, 170 step homing (park) position, 5 step increments, etc. It idled well but my headers started glowing a little which indicated to me that my idle PW was still erratic. (due to large injectors and low PW).
So I switched to alternating injection based on Junk's recommendation, and I re-did my VE table (actually needed more fuel, go figure ?). It seems to idle quite well now at around 900 RPM. Probably the best I've seen it run so far. No weird hunting crap I used to get on $58.
Now that's the good. The bad is that my engine bay is a freaking toaster oven. I probed around with my IR gun. I'm getting nearly 200 degrees on the body, heater box, firewall, wheel wells. The K&N filter was over 150 degrees, the silicone couplers and such the same 150-200 degrees. It's heating the air in the immediate area.
I probed around and pretty much anything besides the headers is stupid hot. I can intercool the crap out of it, but I still don't want my blower inlet temp that hot. All it's going to do is wipe out the seals in my Vortech. So I need a plan for that. I was thinking maybe clock the blower differently and try to do a 180* near the shock tower and pick the air up in the battery tray like Dan did. I dunno.. Might have to make blower mount bracket #4 haha
Next problem is, I'm idling around 180 degrees water temp, but my dash gauge shows like 240-250 degrees. When I shoot the IR thermo at the connector on the CTS (head) I get 336 degrees which is freaking insane. I had this exact same problem 2 years ago with the procharger and SLP headers. I can't bury the CTS any deeper into the head so I don't know. I don't have a spare NPT port on the intake to pick the gauge up. I wonder if I should just use an output from the MS. (can I even do that??)
My shop has some epic echo, plus I had the 24" big fan on to blow the fumes out the door. Once I align the front end I'll pull it out and get some better audio. I just swapped to some Coleman tube-style adjusters for the tie rods and jam nuts.
It runs, and I finished the alignment last night. Now I can pull it out of the shop and put it in storage and start working on something I actually enjoy.
So it didn't make it to storage. Brakes wouldn't stop the car.
So after spending two days troubleshooting that, I swapped to 2.75" front calipers w/out low drag seals, and a 24MM master cylinder. I still have a small problem with my heim joint sticking and the pedal not completly returning, but it's bled and the brakes appear to function properly.
The IAT temps really got to me, so I decided to go back to a front mount intercooler like I had with the Procharger. So I got that bolted up and started the plumbing. I had to move the trans cooler to the bottom of the air dam, so the trans goes into the radiator and then into the cooler.
I have a ram-air 1 hood I need to prime and paint, and them I'm going to try and rig the suction side of my blower to draw air through the hood nostrils.
My IAC stepper circuit fried, but I hooked up with a guy out of Canada who makes these cool PWM IAC adapters for 4 wire GM IAC's, which is great because tuning %open is a lot easier than steps in my opinion. So once that comes in the mail I'll have a working IAC again.
Also moved the Wideband o2 to the Y-merge by the tail shaft, and re-welded some of my exhaust as I had a pin hole here and there.
Very little, that's why I tied it into the radiator first. My water temp never goes above 190 so I think it will be OK.
I'd like to try and snake the IC pipe through the fender by the horns. I really don't wanna relocate my battery to the trunk.
-- Joe
Yea that's what I figured. Maybe throw a tiny dedicated fan on it and move it to a remote location?
I looked at what you were trying to do lol... The horns is why I ran mine by the fender on the pass side (no horns and I run a 75 series battery on pass side) then ran the pipe through the battery tray on the driver side. No way I could squeeze a 3" pipe near the horns.
Yea that's what I figured. Maybe throw a tiny dedicated fan on it and move it to a remote location?
I looked at what you were trying to do lol... The horns is why I ran mine by the fender on the pass side (no horns and I run a 75 series battery on pass side) then ran the pipe through the battery tray on the driver side. No way I could squeeze a 3" pipe near the horns.
Doesn't the procharger IC piping run through that hole by the horns?
My IAC stepper circuit fried, but I hooked up with a guy out of Canada who makes these cool PWM IAC adapters for 4 wire GM IAC's, which is great because tuning %open is a lot easier than steps in my opinion. So once that comes in the mail I'll have a working IAC again.
-- Joe
So you retrofit a PWN valve too it or it acts like a pwn valve?
So you retrofit a PWN valve too it or it acts like a pwn valve?
No, I'm using a regular GM IAC stepper valve. The little box takes in power, ground, and FIDLE and outputs the 4 wire stepper. 0% is 0 steps, and 100% is 255 steps. Makes life easier.
Intresting, I wonder how much more reliable it is, Mine still loses its position once in a while and i have to cycle the key a few times to get it to bottom out.
That intercooler fits in there nice too. What brand and how well did it work?
Last edited by 86CamaroDan; Sep 15, 2016 at 09:46 AM.
Intresting, I wonder how much more reliable it is, Mine still loses its position once in a while and i have to cycle the key a few times to get it to bottom out.
That is what mine was doing, and also sometimes it wouldn't move in a certain direction when commanded. I don't know if it's a problem with the UDN2916 chip that MS uses for the stepper, or the code itself.
Originally Posted by 86CamaroDan
That intercooler fits in there nice too. What brand and how well did it work?
I don't know, I bought it locally a few years back. When I ran the P1SC it got heat soaked pretty quick, but I didn't really road test it.
That is what mine was doing, and also sometimes it wouldn't move in a certain direction when commanded. I don't know if it's a problem with the UDN2916 chip that MS uses for the stepper, or the code itself.
-- Joe
Well please, keep us posted with how it works out. Im on the fence between buying a new GM IAC for 3X the price vs deleting the IAC all together.
Well please, keep us posted with how it works out. Im on the fence between buying a new GM IAC for 3X the price vs deleting the IAC all together.
I've been running mostly without an IAC. I've got my minimum idle speed set to 900 RPM by the throttle stop, but I'd like cold start idle (warmup), and I'd like the closed-loop idle control to work properly as a stall saver. It's not as important on an auto car, but even the little 'bump' in idle I get when the fans kick on would be nice to stabilize.
I've found the majority of MS users are either using fast idle valves, or Ford PWM valves. Very few are using GM or Mopar steppers, and of the ones I talked to none were using closed loop IAC (which is a nightmare to get configured properly, and is the most complex stuff in the world). I wouldn't be surprised if there was a bug in the 'last known steps' vs 'reported steps' code.
yeah i gave up on trying to figure out closed loop. Go figure, i get in it this AM to go to work and its idling high. *Sigh*
Yeah. I had mine wired wrong initially, but even after wiring it properly the movement was inconsistent. The "test mode" would stop working until I recycle the power.
I tried using known correct settings, 170 park position, etc. Still problematic.
GM IAC or aftermarket IAC? My buddy is running a 4 wire(The newer version) in is turbo saturn and hes somehow got it working with a GM one. I wonder if the aftermarket ones are just junk.
Procharger runs by the horns but its uses some funky rubber/silicone couplers so It goign to be pretty hard to mimic that without that specific molded peice. Or maybe they ask you to relocated the horns?
You guys have no many issues with the MS and aftermarket crap lol... Swap to a GM LS PCM/harness with HPT and call it a day lol.
Closed loop...hahaha.... Open loop FTW! I tried closed loop a few times... not a fan. Now I only do open loop and leave the crappy 02 sensors in as bungs. I bought cheap $30 for the pair 02s thinking if I dont get it to work I'm not out too much. They were fine around town and getting on it but once I got on the freeway cruising they went pig rich. I'm already rich in the cruising range but they made it like 9:1. I might revisit it once I verify I have no exhaust leaks.
Aftermarket IACs from my understanding are poo. At least for the LS. The IAC for my 5.3 was $100!!! I wasn't sure if mine was bad but I purchased a cheap one $15 and have it for testing down the road or if I really need it.
Good luck guys... more verification I prob won't ever use MS stuff.
GM IAC or aftermarket IAC? My buddy is running a 4 wire(The newer version) in is turbo saturn and hes somehow got it working with a GM one. I wonder if the aftermarket ones are just junk.
I suspect aftermarket. It's what came in my BBK 58M throttle body,which I purchased from a forum member along with the miniram.
I have a new style (lt1, ls1) style on the shelf but when when it screws in the connector conflicts with the bottom of the trottle body.
I may go buy a new one this weekend, just cuz. I don't *need* IAC, but it's nice to have one.
You guys have no many issues with the MS and aftermarket crap lol... Swap to a GM LS PCM/harness with HPT and call it a day lol.
Closed loop...hahaha.... Open loop FTW! I tried closed loop a few times... not a fan. Now I only do open loop and leave the crappy 02 sensors in as bungs. I bought cheap $30 for the pair 02s thinking if I dont get it to work I'm not out too much. They were fine around town and getting on it but once I got on the freeway cruising they went pig rich. I'm already rich in the cruising range but they made it like 9:1. I might revisit it once I verify I have no exhaust leaks.
Aftermarket IACs from my understanding are poo. At least for the LS. The IAC for my 5.3 was $100!!! I wasn't sure if mine was bad but I purchased a cheap one $15 and have it for testing down the road or if I really need it.
Good luck guys... more verification I prob won't ever use MS stuff.
My car runs mint on open loop IAC settings, I just dont trust the $40 IAC from autozone that looks exactly like the $7 IAC i got straight from ebay/china. "How can you screw up a IAC"...... last time i say that, or buy from autozone at that. I think its time to pony up the cash for a GM one like i had to do with the ICM - Aftermarket crap just doesnt cut it.
Procharger runs by the horns but its uses some funky rubber/silicone couplers so It goign to be pretty hard to mimic that without that specific molded peice. Or maybe they ask you to relocated the horns?
I think they move the horns, which is easy. I may end up just putting the battery in the trunk. I've got the kit, minus the box.
Originally Posted by customblackbird
You guys have no many issues with the MS and aftermarket crap lol... Swap to a GM LS PCM/harness with HPT and call it a day lol.
I couldn't live without some of the functionality the aftermarket stuff has. Plus I really like tunerstudio.
Originally Posted by customblackbird
Closed loop...hahaha.... Open loop FTW! I tried closed loop a few times... not a fan. Now I only do open loop and leave the crappy 02 sensors in as bungs.
That's not what we're talking about. On the MS code you have two different 'modes' for idle control, open loop which is basically a steps (or duty cycle) vs coolant temp. This mimmics the GM code for warmup.
The other mode is 'closed loop' which simply provides RPM feedback. So rather than steps vs coolant temp, it's idle speed vs coolant temp. It also does the a/c idle up and all that fancy stuff.
'closed loop' in Megasquirt speak simply means a feature is using feedback.
Originally Posted by customblackbird
Aftermarket IACs from my understanding are poo. At least for the LS. The IAC for my 5.3 was $100!!! I wasn't sure if mine was bad but I purchased a cheap one $15 and have it for testing down the road or if I really need it.
Good luck guys... more verification I prob won't ever use MS stuff.
I honestly don't know what or where the problem is, but I've found that most megasquirt users either use a PWM valve (ford, etc) or just use open loop mode. I don't know if the software has a bug, or if the UDN2916 chip used to control the stepper motors is a problem.
MS isn't for everyone. There is way too many settings that an average user could completely screw up and be stranded on the side of the road, for example:
For most guys who want aftermarket but are not experts at engine controls, I'd push them to Holley. The only thing I don't like about Holley is the bizarre "lbs fuel" fuel map, but that's probably because I'm used to VE.
The MS was never intended to be used by everyone, and the developers simply couldn't give to sharts if people can't figure out how to use it. It's very powerful if you are an EFI geek. Not everyone wants that level of intimacy with their EFI.
I just like picking on Rob and getting his goat over the EBL. He reminds me of some of the Apple fan boys that work for me.
FYI Joe, The voltage compensation on those injectors isnt .140 like i told you, Its .055 - Ive been fighting a unsteady afr this whole time thinking its my heat soaking IAT and its not just that, Its the damn voltage compensation too. My bad for throwing bad info
FYI Joe, The voltage compensation on those injectors isnt .140 like i told you, Its .055 - Ive been fighting a unsteady afr this whole time thinking its my heat soaking IAT and its not just that, Its the damn voltage compensation too. My bad for throwing bad info
I have my voltage compensation set to .200 and my dead time set to 1.0.
You are running the same siemens deka 60's as me, right?
So your turn on time is 1.14
Your turn off time is .85
This is where I get fuzzy.
Let's say we want to deliver .5msec of fuel. If our open time is 1.14, we need to command the injector 1.64.
However, it takes .85 msec to close. So we're getting a minimum of .85 msec of fuel if we energize the solenoid, so that .5 msec of fuel actually is 1.35 msec.
How could the ECM deliver fuel properly without knowing both the open and close time, in addition to the latency (offset) ?
So.. I've got 5+ inches above my throttle body to the ram air 1 hood, so I think the most logical thing to do is build a ram air box that feeds the blower.
(yes that is child's clay)
I also added the PWM to stepper iac adapter to my ECM, so that should be all set.
The only problem now is, even with a new heim joint my brake pedal won't return the last 3/8" or so. Something is binding (you can hear it) unless I loosen the bolt. Kinda aggravating me. I think the proper solution might be some type of eyelit that has a female 3/8-24 RH so I can just mount it like the oem brake rod.
holy moly thats a mess. you are a software guy, right? lol
i ran a factory style iac with my ms2. it seemed to work correctly, but i had an issue where the idle would be high when i got back to the pits for whatever reason. after 20-30 minutes i could fire the car up and idle would be correct once again. i never looked into it.
holy moly thats a mess. you are a software guy, right? lol
Yeah. EE was a minor. I can solder stuff together, but I'm not. neat. Everything ohms out ok though
Originally Posted by DIGGLER
i ran a factory style iac with my ms2. it seemed to work correctly, but i had an issue where the idle would be high when i got back to the pits for whatever reason. after 20-30 minutes i could fire the car up and idle would be correct once again. i never looked into it.
I dunno. The PWM mod I think will work for me just fine.
I put the driveshaft loop in today.
I've got some brand new MAC subframe connectors I've been thinking about welding in, although, looking at them I'm not convinced they do much.
Also re-routed the air cleaner so it's right above the throttle body. I've got about an inch of clearance to the hood. So now I just need to build an insulated airbox to draw air in from the hood nostrils.
Also re-routed the air cleaner so it's right above the throttle body. I've got about an inch of clearance to the hood. So now I just need to build an insulated airbox to draw air in from the hood nostrils...
This is going to be interesting to see how you fab one up...
So your turn on time is 1.14
Your turn off time is .85
This is where I get fuzzy.
Let's say we want to deliver .5msec of fuel. If our open time is 1.14, we need to command the injector 1.64.
However, it takes .85 msec to close. So we're getting a minimum of .85 msec of fuel if we energize the solenoid, so that .5 msec of fuel actually is 1.35 msec.
How could the ECM deliver fuel properly without knowing both the open and close time, in addition to the latency (offset) ?
-- Joe
Yeah, I never really understood how i was supposed to get a accurate number on it. Everybody on the MS facebook forum kept telling me to unplug the alt, and adjust it untill the afr didnt change from alt plugged in to alt charging. All i know is i dont have any afr issues with day time vs night now.
Are you sticking with the RA hood, or maybe going with a cowl induction in its' place?
I've got both in my other shop. Right now I have the RA-1 hood bolted on and it's got really nice clearance. My thoughts are to use the nostrils to feed the air cleaner (think C4 style box), and maybe cut the back open as a cowl to exhaust engine heat.
The cowl is a harwood 3". I think the RA-1 hood looks better on the formula.
Honestly, I'm tempted to take the blower off and put it on my '75 and just run the firebird n/a, but.. Then it wouldn't be as fast haha.
Yeah, I never really understood how i was supposed to get a accurate number on it. Everybody on the MS facebook forum kept telling me to unplug the alt, and adjust it untill the afr didnt change from alt plugged in to alt charging. All i know is i dont have any afr issues with day time vs night now.
Yeah, I read some of that. I understand what they are doing but it's an experiment to find the correct numbers because the software doesn't have the proper functionality. I brought a number of things up to James and he told me to **** off.
The code is very straight forward, but if I "fixed it" and released a patch that would be in violation of the license agreement. It's quite frustrating.
There is also some confusion over the reported pulsewidth, if it's accounting for the dead time or not. I gotta take a look at that when I have some time, but I'm pretty sure it doesn't account for dead time (meaning your fuel use usage calcs are off if you are using tunerstudio to report fuel economy).
I've got both in my other shop. Right now I have the RA-1 hood bolted on and it's got really nice clearance. My thoughts are to use the nostrils to feed the air cleaner (think C4 style box), and maybe cut the back open as a cowl to exhaust engine heat.
The cowl is a harwood 3". I think the RA-1 hood looks better on the formula.
Honestly, I'm tempted to take the blower off and put it on my '75 and just run the firebird n/a, but.. Then it wouldn't be as fast haha.
-- Joe
I say go for it! I'm going to dyno the 305 without the boost pressure while I wait for the right rebuild kit to show up at my door, so until then the long tubes are going back on and I am going to see just what the 305 with everything I did will do. Would like to see what your Formy will do naturally aspirated myself. Slap that blower on the '75 Corvette. Man I love that style, w/those the "coca cola bottle" style fenders. Last year for the 454 too..
I say go for it! I'm going to dyno the 305 without the boost pressure while I wait for the right rebuild kit to show up at my door, so until then the long tubes are going back on and I am going to see just what the 305 with everything I did will do. Would like to see what your Formy will do naturally aspirated myself. Slap that blower on the '75 Corvette. Man I love that style, w/those the "coca cola bottle" style fenders. Last year for the 454 too..
I think my 412 should make around 480hp naturally aspirated. That's not terrible for a street car, but not impressive either.
I probably could have gotten away with a V3-S trim though to meet my power goal (600hp) rather than the T-trim.
If I put the blower on the vette though I'd have to do a new motor unless I put the whole engine in the vette and did the 5.3 in the Formula.
Well 480 is a lot more than 300 lol, that's what mine puts out. 480 is nothing to sneeze at. My 95 C4 bone stick ran high 13's when I took it to the track last year, the GTA needs to best that without the turbo and only on motor...
Edit: just realized you said naturally aspirated, I calculated mine at a tad under 300 to the tire during my datalog. I'm intrigued to get it to the track now, is there a track near you Joe...?
Originally Posted by anesthes
I think my 412 should make around 480hp naturally aspirated. That's not terrible for a street car, but not impressive either.
I probably could have gotten away with a V3-S trim though to meet my power goal (600hp) rather than the T-trim.
If I put the blower on the vette though I'd have to do a new motor unless I put the whole engine in the vette and did the 5.3 in the Formula.
-- Joe
Last edited by Street Lethal; Sep 26, 2016 at 10:53 AM.
Well 480 is a lot more than 300 lol, that's what mine puts out. 480 is nothing to sneeze at. My 95 C4 bone stick ran high 13's when I took it to the track last year, the GTA needs to best that without the turbo and only on motor...
Edit: just realized you said naturally aspirated, I calculated mine at a tad under 300 to the tire during my datalog. I'm intrigued to get it to the track now, is there a track near you Joe...?
I'm talking about flywheel horsepower, not whp.
New England Dragway is about 20 minutes away. I have a trailer and everything. Our track is a legit NHRA national event track, and tech is black and white. We can't get away with the stuff you guys get away with (running 8 and 9 second et's on 11 second cars). The tech inspection is a legit tech inspection, not a wink and a nod. I've broken out on a pass, and have been suspended for running a faster ET than the car was inspected for.
I'm just not sure what I want to do with the car. Like performance wise, I'd like it to be a 130mph street car. But I'm not really interested in bracket racing anymore, and haven't been in over a decade. I may run it a few times on a street night, but that's all.
If I ever got back into competitive racing, It would be a rail car not a production car.
