The leak is from the iac not being able to fully close and seat because I dug into it with a carbide bit while opening up the OD of the larger hole that IAC body sits in. I'll have to check on the kpa
BUILD THREAD Project long time coming
- Thread starter Streetbu
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Alright. Next issues LOL
MAT sensor reads WAYYYY off. Like 50 degrees off. And so does fuel pressure. I'm using the Low Doller fuel pressure sensor and this MAT sensor which is what I was told would work. Any ideas?
MAT sensor reads WAYYYY off. Like 50 degrees off. And so does fuel pressure. I'm using the Low Doller fuel pressure sensor and this MAT sensor which is what I was told would work. Any ideas?
Do you know how to scale a sensor in the software?
I wouldn't get too excited about a sensor offset until you have it running enough to drive. Once you get to that point adjusting any sensor is pretty easy.
I've bought all of my open air IAT's from here : https://www.diyautotune.com/product/gm-open-element-iat-sensor-with-pigtail/
I've tested and adjusted them with Holley and Megasquirt systems. Dialing them in is really easy and nothing to be concerned about at the point you're at presently imho. FWIW, that sensor in original GM form will rarely if ever read erroneously. I scour the local yard for them but they are rare in stock form.
The link I attached give the ohm readings at various temps. Check yours against those numbers.
I wouldn't get too excited about a sensor offset until you have it running enough to drive. Once you get to that point adjusting any sensor is pretty easy.
I've bought all of my open air IAT's from here : https://www.diyautotune.com/product/gm-open-element-iat-sensor-with-pigtail/
I've tested and adjusted them with Holley and Megasquirt systems. Dialing them in is really easy and nothing to be concerned about at the point you're at presently imho. FWIW, that sensor in original GM form will rarely if ever read erroneously. I scour the local yard for them but they are rare in stock form.
The link I attached give the ohm readings at various temps. Check yours against those numbers.
I went to the scaling section, but from what I saw, that's only for the minimum and maximum readings and where you want it to alert you it is out of range.
I guess my concern is that the fuel/air ratio is reading 13.8ish, but it's so rich it almost burns your eyes. Worse than my sbc with a quadrajet. Which doesn't make sense if it's actually around the ratio. So that made me look at those two and noticed they were reading way off.
I guess my concern is that the fuel/air ratio is reading 13.8ish, but it's so rich it almost burns your eyes. Worse than my sbc with a quadrajet. Which doesn't make sense if it's actually around the ratio. So that made me look at those two and noticed they were reading way off.
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If it’s burning your eyes at 13.8 : 1 , then you’re afr reading is incorrect. You have an exhaust leak, intake leak, wrong O2 sensor picked or something fubar’d.
I know it’s hard to do what I’m about to recommend, ignore the o2 reading until it’s hot. I cold start and warmup at 12.5:1 on gas. And once warmed up 13.8-14.2:1 at idle.
What kpa idling at 1100, 1000 and 850 rom
Mr. 64nailhead you are a treasure to this forum.
Thanks Tony, but not really. I’m anal retentive, and I’ve struggled with these little things that turn out to be so minor after you figure them out, that it seems silly to worry about them.
If Shawn can get it to idle smoothly at 16-22degrees of timing, and 900 rpm’s , then he can adjust the fuel table by smell - I know that sounds crazy, but it can be done. If you turn off all of the o2 feedback, you can actually tune the car by plug reading, performance and sound. I’ve fried an Innovate lc2 sensor and worked around it. Naturally aspirated it can be done, I wouldn’t try it with nitrous or boost. Just the same as a carb and dizzy.
51 kpa at 775rpm idle. I'm 99.9% sure I don't have any exhaust or intake leaks. I turned off idle smoothing and set idle timing at 15°.
Is it running smooth?
Set idle in the tune to 875-900 and let the iac get it there. Then once it’s warmed up adjust let Holley adjust it to the afr of choice.
I know I've asked before, but what are the cam specs?
Set idle in the tune to 875-900 and let the iac get it there. Then once it’s warmed up adjust let Holley adjust it to the afr of choice.
I know I've asked before, but what are the cam specs?
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Yes it's seems to be running great other than the rich exhaust smell. Idles smooth, revs great. Has the SS2 cam, .585 lift intake and exhaust, 228 intake duration 230 exhaust. Small cam really.
Don't sell the SS2 short - it's a giant cam in a 4.8, really big in a 5.3 and large in a 6.0. By modern standards of Brian Tooley Racing, Texas Speed, etc, it's not viewed as somewhat small. But for a street driven vehicle it's 50+hp over a stock 19_/19_ duration in a 300+hp stock engine. And easy on the valve train as well as compared to 620+ lifts on a crazy ramp. In old school thinking, it would be considered a mild (small) cam on a 555 BBC.
A datalog and tune fie attached would be great.
