Here comes another single turbo TPI 5.7 87 Iroc - Page 2 - Third Generation F-Body Message Boards

Orr89RocZ · 10-08-2009, 12:54 AM

nice how is megasquirt treating you?

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ZZ3Astro · 10-08-2009, 01:20 AM

The megasquirt has been great so far. I'm still trying to figure out the accelerator enrichment setup but the overall tuning and driving experience has been wonderful. I am still chasing an IAC issue on occasion that seems to be related to high temp conditions only. Did you get your code 59 running good yet? I don't miss the rominator box but I do wish I could haven't made this work with OEM stuff and 59 just on principle. It would have been cooler, especially since I'm keeping the stock TPI setup. The autotune feature in the MS though, that really makes it worth the change alone.

Here's another pic I thought I'd ad to show the heat shielding I did for the AC system. I used thermal barrier tape (came from autozone) on the AC lines, AC box and on the exposed side/top/bottom of the drier/filter. I also zip tied a strip of header wrap to the AC line where is is close to the turbine housing. I added a piece of aluminum (cut from duct material from home depot) around the drier/filter and used a stainless ziptie to secure it. And now I have the PTP turbo blanket along with the wrapped downpipe.

Orr89RocZ · 10-08-2009, 07:39 AM

Car is running on 59 alot better now. Actually idles fairly well and have no other real issues. Drove it around abit but havent really gotten on it. Just heavy part throttle rolls to near 4000 rpm. I am looking into a FAST setup just because I may beable to get one at a decent price and the local shop near me can tune it in a couple of pulls. Expensive upgrade but atleast the car will be tuned and done and I can start racing it before the year is over

BirdsOnly · 10-08-2009, 10:14 PM

Sorry if I missed it. Are you still running MAF or MAP? How do you handle the fuel? Does the megasquirt have a boost reference or are you using a boost reference Fuel pressure regulator?

ZZ3Astro · 10-08-2009, 10:35 PM

Running the built in 2.5 bar map in the Megasquirt. I also have a 3 bar map in my PLX vac/boost unit that I may hook up so I can use the built in one for barometric calibration. I'm still using the stock fuel pressure regulator with 65# precision turbo injectors. The megasquirt handles all fuel requirements and I'm using a PLX wideband O2 for automixture and autotuning.

BirdsOnly · 10-09-2009, 02:04 AM

So your running a MAP with positive pressure resolution? The car was originally MAF? Awesome job getting it going!

ZZ3Astro · 10-09-2009, 11:18 AM

That's correct.. it was orginally a MAF car and then I converted it to speed density with a 7730 ECM from a new third gen. It ran and drove great on the 7730 with the 8D bin. I was planning to use Code 59 and 3 bar map but I had a lot of problems getting it to work right once I went to the larger injectors. I finally yanked the factory harness and computer out and went to the Megasquirt. Haven't looked back since :-)

BirdsOnly · 10-10-2009, 03:13 PM

I didnt see it in the photos, but how doe the driver side exhaust enter into the turbo/log set up? Does it go around the back of the engine or the front?

ZZ3Astro · 10-10-2009, 07:32 PM

The crossover follows the stock location of the Y pipe from the driver side manifold, across the bottom of the oil pan just behind the crossmember and then turns up and into the passenger side turbo manifold instead of turn towards the back to form the Y.

BirdsOnly · 10-11-2009, 12:52 AM

Quote:

Originally Posted by ZZ3Astro

The crossover follows the stock location of the Y pipe from the driver side manifold, across the bottom of the oil pan just behind the crossmember and then turns up and into the passenger side turbo manifold instead of turn towards the back to form the Y.

stupid question.... does it enter into the passenger side manifold itself or are they joined in a y-pipe just below the turbo?

ZZ3Astro · 10-11-2009, 03:20 PM

Look at the middle of page 1 of this thread and there is a photo of the manifold before I mounted it. You can see the merge inlet.

Bones232 · 10-15-2009, 08:58 PM

zz3astro - what fuel and timing are you running? Did you have to go with 93 or better?

ZZ3Astro · 10-15-2009, 11:06 PM

Running 93 octane. Timing is fairly conservative at this point. It really falls off above 7 psi but peak timing is around 18-20 degrees (maybe 22 over 5000 rpm) at 6.5 psi then starts taking a lot out. Once I get my fuel pump and intercooler in place I'll change that a bit. I also have it start pulling timing out pretty aggressively when the IAT exceeds 140. Mostly its intake heatsoak producing readings like that, but I don't want to take any chances now.

V8Astro Captain · 10-19-2009, 10:08 PM

Glad to see it working so well. I've kinda been skeptical about the MS system over the years. I just checked out the website and it seems they've come a LOOOONG way from what I remember.

Sadly I'm stuck with this Holley Commander train-wreck. Arg...what a cumbersome system....

ZZ3Astro · 10-20-2009, 10:24 AM

I felt the same way but I've been pretty impressed with the overall experience. My biggest complaint is lack of sensors and outputs. I'd like to see inputs for speed, AC on among others and some additional outputs. As I understand it, a new megasquirt-III prototype is already in testing and it will have a lot of the things I miss on the II.

Would be nice if it was a plug and play changeover from the II to the III. Hopefully all these new features won't run the price up to the levels of other ECMs out there.

ZZ3Astro · 11-03-2009, 11:03 AM

Another update on this car...

Overall things have gone pretty well. I took it for a 135 mph run (it pulled hard to 120, after that it wanted to downshift to 3rd so I kept having to back off the gas) and came back with a strange sound in the exhaust. Fast forward about two weeks and I was under the car to check plug #8 because the wire lays across the downpipe. The pipe is wrapped and the wire has an insulator boot, but I figured it was burnt. It was not! However I found a pretty big problem in terms of a major exhaust leak and a missing lock washer - arrow points at #6 cyl:

The manifold material under this missing washer is very rough for some reason. I think it cracked the lock washer causing it to fall out. So I took everything back off, ground it smoother and welded a flat washer on to protect the new lock washer. I also tried flipping the copper gasket over the other way (it is oversized for this manifold)

Everything went back on and I fired it up. The leak was even worse! Bear in mind I was trying to make it to the dragstrip that same day. Everything back off again far enough to remove the gasket completely and put it back together. I started it up and the leaks are gone!

Back under the car for final inspection, I realized the #4 spark plug wire was hung up on the v-band clamp for the crossover pipe. This is very bad because #4 is the worst plug to get to. It is blocked by the crossover pipe on front and below, the manifold above and the downpipe behind and outside. Somehow I got the wire off. It was burned about 4" of its length, having been exposed to the exhaust leak. This one I didn't have an insulator boot on either since it ran under the manifold. Obviously I didn't make the dragstrip this weekend.

All turned out great though once I replaced the wire. It's running great and I'm really seeing an improvement with getting on the boost. I can actually launch at 1 psi on the stock converter now (on concrete) and I have been able to brake boost to about 3 psi. That leak has probably been there since day 1 from the looks of things.

If I don't break it and the weather is good, I am hoping to have it to the track this coming weekend.

noboostnogo · 11-03-2009, 10:29 PM

Glad to see this thread is still alive!!! ahh it sucks you didnt get a chance to go to the dragstrip, ive been following this thread since the day you started it. what do you think the car will run if you get it to hook?? great job on everything

ZZ3Astro · 11-04-2009, 09:34 AM

Thanks noboost. I'll be running 8.5 psi and originally expected 8.20's 1/8 mile on 12 psi (with a 2.0 60 foot, before I knew this thing would launch this hard) so somewhere in the mid 8's is what I'm hoping for. I've had to pull a lot more timing out of this thing than I expected (total timing is around 14-15 at full boost) so that will be my excuse if I run crappy numbers. Saving up for the intercooler supplies now.

Hope I don't break anything.. planning on a 200 mile drive on Thanksgiving day to visit some relatives in style.

My wife doesn't think it's a good idea to stick my elderly mother in there for the trip, knowing I won't be able to resist some highway boosting.

junkcltr · 11-04-2009, 12:24 PM

Your 14-15 timing numbers seem reasonable for a stock compression 5.7 liter TPI. I run about 16* BTDC max. with my completely stock 9.5:1 compression 305ci TPI at 9 PSI of intercooled boost with 87 octane. I add in some timing when the water/alky comes on.

Orr89RocZ · 11-04-2009, 12:51 PM

I dont think you'll have any problems reaching low 8s 1/8 mile with that setup. my buddys bolt on L98 with procharger at 10psi-12psi was in the mid lower 12's in the 1/4. i'd expect you would be near high 7's in the 1/8 if the launch is strong

ZZ3Astro · 11-05-2009, 12:09 AM

High 7's would be killer. I took it out today and kept having issues with breaking up at higher boost. Also it pulled great at 4 psi and 8 felt like someone holding the brakes. Finally I got out an checked the wire coming out from #4. The crossover pipe had some funny marks on it and when I pushed the wire a bit closer it started arcing over to it (about 1 inch). So during low boost it was still able to fire the plug but in higher boost it was easier to arc over. That wire must have touched at some point and ruined the insulator. I have some new wires to put on and heat insulators but that means I have to take the downpipe off instead of spending the day driving it! What fun is that?

Anyway I made a vid today even though the ignition problem was present. Not as much go here as before the wire problem but it's more fun to look at than a boring post alone. Also you can hear the blowoff valve releasing. These are 0 psi launches so nothing amazing to see...

http://www.youtube.com/watch?v=7vTeKzSbUtg

ZZ3Astro · 11-08-2009, 08:55 PM

Finally got it to the local 1/8 track today. There were no surprises (good or bad) as it ran several 8.67's at 82.x mph. Pretty much where I expected it to be, especially with this 80 degree weather today. 60 footers were 1.9x mostly, no 1.8's as I'd hoped. I redlighted two or three times on the first runs trying to find the stall point for launch. Basically with this stock converter about all you can do is load up the brakes. When I get a converter so I can leave on a few pounds of boost it will be a different car.

Overall I'm very pleased with the results today. I did five passes hotlapping, rested it for an hour and made another pass. After that I turned it over to my wife and she pulled out a 8.68 with me in the car and then matched my previous 8.67 alone. She was all smiles as it was her first time down the track. I think she's addicted.

http://www.youtube.com/watch?v=SISnh...eature=channel

Orr89RocZ · 11-08-2009, 09:38 PM

Not bad, that car reallly needs sticky tire and converter and you'll be well into the 8's. Cooler air and less hotlapping would help alot too

ZZ3Astro · 11-08-2009, 10:26 PM

Well no tire spin at all.. tire spin would have helped because I wouldn't have kept redlighting. The front brakes just won't hold the car if I stall it up much at all. A looser converter and some 50 degree temps will put it low 8's for sure.