ok, so i have a 383 that i built up when i was in high school and have been upgrading ever since.

specs:
HSR intake
52mm TB
Kirban afpr
30lb injectors
pro comp heads
1.5 roller rockers
11:1 compression ratio
cam specs: flat tappet version of tpis zz409 cam
Intake Exhaust
Advertised duration 280 280
Duration at .050 224 224
Gross lift .495 .495
Lobe separation 112

now my issues:
I went to tpis for a chip to put in my computer. Ever since it cuts out when i first give it gas and then runs crazy rich when WOT. I had to replace my spark plugs 3 times so far and am getting really tired of it. I downloaded tuner pro rt and have been reading on how to tune for the past 2 weeks. I would really like to be able to tune my car myself but i know that since the car is a 85 that the computer is really slow so im guessing data logs would be useless. Also if you didnt catch it in the specs, it has 11:1 compression so it pings at higher rpm (i was young and thought if an import can run 11 to 1 then my 383 can, wish i knew then what i know now). So heres my questions.

Do i have to swap computers to be able to tune my engine?
Is it just the compression screwing with the computer?

 

Compression won't screw with an ECM but it does not like low or fluctuating vacuum which your cam could cause.

You don't need another ECM the old slow ones will tune for what you need. If you want to learn tuning and do it yourself look at Moates.com or search here for RBob and his EBL conversion done to your ECM for complete tuning. The EBL does have advantages over the stock ECM programming. HTH

 

I have been looking at the ostrich 2 system so i can tune in on the fly. it seems to be the best way for me to go considering im still on a college budget for another year.

i was concerned about the compression because of the knock sensor telling the ecu to retard the timing. Does that affect much?
I just don't get it because it idles and cruises fine its just the fouled plugs and cutting out i dont get

 

After the Ostrich you still need a burner. So go up one more step to AutoProm and never look back!

 

i heard you could just leave the ostrich plugged in instead of burning a chip

 

That is true. I have done that very thing in my Datsun for the last 3 years.

A programmer is nice to have, so that you can read the EPROM you have now, and start from that, and/or be able to program the file tune to an EPROM and run off of it, saving the Ostrich for another day or being able to use it on another vehicle.

You could start with a stock bin though, that you could likely find at moates.net or http://www.eagle-mark.com/Forums/ and tune from there.

Swapping ECMs is also an option, this would allow you to change to a newer code, that could be argued as "more refined," or just more supported so it would be easier to get advice on. The quicker datastream is also very nice. Personally I prefer to tune ECMs that have the faster (8192 baud) data rate, than the slower (160 baud) ECMs.

 

So the ostrich is left in the vehicle, hooked up to? the AutoProm hoks to the chip socket.

I'm guessing but when the ostrich is left in vehicle no laptop is required...

 

That is correct, The Ostrich doesn't need a laptop to operate. The only exception I have found so far is in the '7747 ECM, since it doesn't seem to power the Ostrich in the same way that the '7730 style ECM does.

The Ostrich also plugs into the EPROM socket, since it is also an EPROM emulator, just like part of the AutoProm.

 

also i should mention that tpis has fitted an adapter to my ecu so that a different style chip could be used. since im a civil engineer and not an electrical i cant really tell the difference

 

would the ostrich be able to tune a procharged 383? I am planning on buying some forged dished pistons and a procharger after i graduate and would like to be able to tune it myself by then

 

You can run aluminum heads on pump gas without pinging at 11 to 1 but need a decent sized cam for it. That cam is abit small for a 11 to 1 383. Your likely running too much timing for the motor and just need it tuned to stop pinging. its gonna need 93 oct gas for sure. Try 30-32 deg max at WOT and see what happens. That chip may have 34-38 deg and will be too much for that higher dynamic compression.

 

The Ostrich can be used in place of an EPROM, so yes it can be used to tune the 383.

 

with out having a tuner i got the distributor in a spot were its a toss up on wether it will ping or run like a raped ape. My car seems to love cooler weather. I am going on an engineering co-op in a couple weeks so ill have some money to buy the ostrich and see whats going on with this thing.
The ostrich will come with the cables buying it from moates wont it?

 

The Ostrich comes with the EMU cable, that plugs into the EPROM socket and the USB cable.

What cables were you asking about?

 

those were the ones i was talking about... Thanks for all the help guys
Is there a site where they upload bin files so i can compare my tpis tune to a tune of a similar set up? I want to be able to see how screwed up it really is

 

check .bin's at Moates site under downloads.

 

There are also about 600 bin files and 200 definition files in the phot gallerey at:
http://www.gearhead-efi.com/

Hope you find that useful!

 

I just got an ostrich and downloaded a stock 85 870 bin. Is there anything i should change on that bin before i try running my engine on it and do some datalogs?

 

I never messed with 85's because the 86-89's are so much better to work with. I'd seriously consider upgrading to the 86-89 ecm stuff. Wiring diagrams can help with the swap. you'd need an ecm which are cheap and a new MAF which is not all that cheap but if you found used it wouldnt be so bad.

 

yea i've looked in to that. Thats not something i want to get into right now. maybe over winter

 

so i did a couple datalogs and i noticed its throwing a code 34 low MAF and for some reason its in closed loop and the fans on. I dont get whats going on if you got some input to whats wrong please let me know.

this is what tunerpro is telling me at idle.

1025 engine speed
.55 TPS
131 coolant temp
55.42 coolant temp
75.2 MAT
24.0 MAT
10.5 MAF
1.25 injector pulse width
100 BLM
112 INT
328.56 O2 sensor
86 O2 crossover
104 IAC position
19.14 EGR Duty Cycle
67 Load variable
CLOSED Loop Status
ON Fan Request
YES ALDL Mode
Yes Crank Pulse
ERROR 34 MAF Low

 

check your MAF wiring and relay for that code 34 maf low. Also may need to open up the throttle blade abit at base idle settings, to lower that IAC. 104 is abit high, get that down into the 20's or so.

100blm 112 int is reading abit rich but that o2 reading is abit lean. Not sure if that o2 sensor value was randomly picked while it was switching or if it just stuck to that value. Either way check the plugs and see if its indeed rich at idle. Make some corrections to the MAF table 1.

 

If it was the MAF burn off module i would think the MAF woulnt work at all. Since it seems to be reading ok from what i logged Im assuming its something else. The MAF i got is the adjustable type... Im leaning toward replacing it with a stock replacement.

And yes it runs very rich at idle. i want to fix the code before tuning. From what ive read on here that code can make the engine run like crap. i reset the TPS, replaced my valve cover breather with just a plug, and made sure i didnt have any vacuum leaks.

 

From what I've read and seen on these forums, the adjustable MAF's do not work well. Replace with a stock unit if you can.

 

Your numbers don't look all that bad. But I agree with Orr89 that the o2 is low trending rich but may be in change over so you need to watch that and see what it is really trending. Rich or lean? Being in closed loop it needs to be over 400 so it seems like it was just a one time shot. Fan on at that low a temperature is a problem. Probably a programming error. I'd certainly look at the TPIS chip as it may be the problem. They are a great small company nearby and I have recently worked With them and supplied them with converted memcals as the factory source for these older Memcals has dried up. Programming can always be a source of problems especially on heavily modified engines. I agree with others that the 85 ECM and memcal can be problematic. But if you are going to change anything, upgrade the complete system to a 90-92 SD system and 1227730 ECM and Memcal. Search EBay for AUJP memcal and you will find what you need.

 

Im guessing my problem with the fan being on and my alternator not charging is in the wiring since it worked fine before i took the motor out. Ive taken the motor out 4 other times with no problems so i dont get why its deciding to be a btch this time.
Also I've always heard MAF is better for modified motors than SD. Would that require my to change out the whole harness? I plan on getting a procharger or turbo when i get out of college and get myself an engineering job. Which set up would be better?

 

Technically MAF is better but MAP is simpler and does the job very well. Ever wonder why GM went from MAF to MAP during that time? Probably to save money but still it is a well engineered system. I'm sure once you have that degree, you'll know which is best for you so I wouldn't worry about it until then. As for fan, if the SES light isn't on continuously, then you are probably correct that it's a wiring issue. One of the signs for being in limp home mode is a constant running fan so take that into consideration.

 

By the way, was the motor that cold when you logged it? only 131f? over 1000 rpms and IAC at 104 counts and throttle almost closed. Does it idle down when warmed up?