Project Lex (aka: Teh Bean) '92 SC300

[Halon]

Well made a discovery last night. Realised that I have no IAT sensor anymore since I ditched the stock MAS. Because of that, my IAT signal in MS was sometimes at -40*, and sometimes at 170*, and sometimes some blip in between there. That caused some random bouncing around in my AFR's.

So I will eventually have to get some kind of IAT sensor installed. But for the time being, I've bolted the stock MAS down in the engine bay, and plugged it back in. That way I atleast have a signal so it doesn't bounce around, and it atleast corresponds to the temp in the engine bay.

Car is cruising around and idling much better now. However I do need to tweak some of the settings now because I was tuning around that goofy issue this whole time before realising it. Oh well no big deal.

Anyhow, here's a quick little vid I put together for you guys to see how she drives around town. Maybe Megasquirt will start to get seen as an affordable option to consider, and grow in popularity

http://www.youtube.com/watch?v=59L06JGwnrc

 

[toyotanos]

3/8npt weld-in bung and a GM IAT sensor and pigtail FTW. Super easy to install and readily available if it were to fail.

 

[Halon]

Sweet. Any pointers on where to pick one up at?

 

[toyotanos]

The IAT sensor and pigtail should be stocked at NAPA stores (they were when I went last time) otherwise you can go online(ebay) and get a kit. As for the bung, same situation- ebay should have them or you can buy a 3/4"od slug of Aluminum and weld it ont your intercooler piping, then tap the threads into it. I prefer the sensor to be near the TB for the most accurate readings. in your case I'd put it right where the piping passes through the fender wall.

 

[Halon]

If I go to napa they are gonna ask for some kind of year and model of car. What year and model did these come on? I'm guessing if I just walk in and ask for a Gm IAT the dude is going to give me the blank stare of death.

 

[toyotanos]

This is what I'm using:
http://cgi.ebay.com/ebaymotors/AEM-...r_Truck_Parts_Accessories&hash=item5191eee7e3

Not sure where the GM sensors come from, I was just told that they were mostly the same?

 

[Halon]

Thanks for the pointers. I ended up ordering one of these today:
http://www.diyautotune.com/catalog/gm-open-element-iat-sensor-with-pigtail-p-62.html


Tune appointment setup for Monday of next week with Shane Can't wait. For some reason I fully expect to find some issues while on the dyno, which is OK because it seems like that's the point. Uncover issues never noticed on the streets, and hopefully end up with a full tune, or a small action item list of things to fix for the next dyno appointment

Also I drove it appx 400miles this weekend to Ottertail and back. It drives around excellent! WOT is still a bad idea (ignition break up) but as far as cruising around/low throttle/part throttle/idle, all is doing just great! I averaged a speed of around 75mph on the trip up there, and got 19mpg on E85 at AFR's right around 15-15.5 mostly. Also hit a bit of rush hour that I'm sure didn't help. But im hoping once the car is really running well, consider going to a slightly leaner burn at hwy cruising speeds to try and better that.

And also ordered up a dozen BCPR7ES spark plugs so I have some in hand in case we need to change them out on the dyno for any reason Getting ready!!

 

[Halon]

Just bought all the parts required for the IS300 ignition setup (IS300 coils & wires, DS62 igniter). This will have to be done post dyno tune, but still it'll be exciting to ditch that big ugly distributor.

 

[toyotanos]

:bigthumb: Its a great setup IMO. Easy to deal with and it usually works with the factory tacho (not sure if your SC is similar to the Supra, though)

Good luck, Shane's the freaking man! If you make more power than me I'm going to cry myself to sleep for a week.

 

[Halon]

I will too because if it makes that much power, my tranny will be in a million pieces lol. This is going to be a low boost tune, running straight wastegate spring pressure (pretty sure it's a 1bar spring). So I'm aiming to be closer to around 400hp for now. I must resist temptation to turn it up until I get a better tranny in there because it will blow.

 

[Halon]

Got the IS300 ignition setup in the mail. Was planning on installing it this winter but ignition issues are making me reconsider.

Also bought some raw materials that I will be using to make my own FFIM. Spending over $800 on an aftermarket plenum, yeah right :uh:

Lastly, hopped on the dyno today for my first official tune. Low throttle type stuff is pretty good. WOT is an issue. I'm not completely sure what the issue is yet, but soon as I was hitting about 8psi the car would break up really bad. Tried a bunch of stuff in the tune but nothing really helped. We swapped out the coil, coil to cap wire, and igniter with one from the shops car. Seemed to improve a lot but boost shot way up (we thought it would be around 15psi steady). Think I may have hooked up to the wrong Port on the WG. Decided to call it a night. I'll be fixing the WG port issue, and then using the parts off his car, see if the break-up goes away. May just be my coil is degraded.
Big thanks to Shane at DB Performance for doing his best with her on the dyno. Will have to get the stuff fixed on my end and bring it back.

 

[Halon]

Well big thanks to Shane for letting me borrow parts from his car. I did some troubleshooting tonight and looks like I've narrowed down my mis-fire issues to my old degraded coil. With his coil, the car hasn't mis-fired yet. I do have a spare coil laying around I believe. I will try that tomorrow and if it works then great. If not, then I will be on the hunt for a new coil.

Also found out that I had made a mistake hooking up my wastegate. That is now fixed as well. Think I will see what the dyno schedule looks like for next week and try again

 

[Halon]

Did some more troubleshooting. Problem was definitely my old coil. Luckily my spare junkyard coil appears to be good. Boosting at 10-12psi on the junkyard spare, and no signs of misfires Dyno appt has been setup for next Tuesday, should be more successful this time around.

Spare Junkyard coil installed and working like a champ!

Pile of troubleshooting parts Thanks again Shane.

 

[toyotanos]

Nice job figuring the ignition thing out, Brandon! I know its a big pita when stuff goes bad, but I think it might have been a saving grace given that WG issue!

 

[Halon]

Yeah thanks man. I call yesterdays session a "Successful Failure" because although I failed to make a full clean pass and get a full complete tune, it helped me successfully diagnose a couple issues, so it was still a successful session in that aspect. I already feel much more confident about next weeks dyno session

 

[Halon]

Car is still running like a champ. So I'm not going to touch a thing until dyno day. So for the time being, started planning some misc stuff. Since I'll be making my own Intake Mani, I was thinking about what to do for vacuum ports on it. So made this crude drawing showing the simplest and cleanest way to run to run these lines. It involves using a couple Tee's which I'm not 100% a fan of, but seems like it would end up being the cleanest and simplest way of doing things, because some of them it means I only have to run one line and the 2 components are somewhat close to each other so then I just Tee it right near the components, rather than running 2 separate lines. Just a little simpler and cleaner. And where I use a Tee, I use a larger line feeding the Tee which is 2 smaller lines to hopefully reduce any issues with pressure loss or whatever could be caused from running a Tee.

But, interested to hear other peoples thoughts...

 

[toyotanos]

I've been told that wastegates should not see vacuum. I'm not sure on the reasoning, but until I find definitive evidence otherwise I'm sticking to that.

 

[Halon]

Hit the dyno today, went much better this time around. Dyno video with results will be posted in the next day or so Here's some teaser pics:

 

[Halon]

Alright so here's a rundown of the dyno.

To start from the beginning, I dyno'd a week ago. Got all the cruising type tuning done, car is running and starting great. But couldn't do any WOT tuning because of what turned out to be a bad coil. With the coil replaced, I returned to the dyno yesterday for the WOT tuning.

You'll see the first run was at about 339hp. Shane did his thing, 2nd run we were already up nearly 50hp. A handful of more pulls and we stopped it at 406hp which far exceeded my expectations (I was thinking more like 360). This is on straight WG boost, no boost controller. You can see how soft boost comes on with this WG. I thought it was a 1bar spring but maybe it's more like a 10lb. Will have to look into swapping that out this winter.

I can't thank Shane enough, I'm very happy with the entire experience (as always). One thing you'll notice is a random blip in the curve at around 3500rpm. It would occasionally miss at that spot very slightly. Not exactly sure why but not that worried about it either.

So I've attached the 3 charts (HP vs. Boost vs. TQ vs. AFR). Creeps up to about 12psi at the end.

Also attached is a little video. Thanks to Kerry for taking some good footage at the dyno, enjoy!!

http://www.youtube.com/watch?v=cRN1QyANeS8

 

[toyotanos]

:bigthumb: Nice work, Brandon! Looks a bunch like my first dyno in the Supra, but you're 5lbs less than I was!