C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

85 chip tuning

Thread Tools
 
Search this Thread
 
Old Aug 22, 2013 | 08:16 PM
  #1  
Jakez89's Avatar
Jakez89
Thread Starter
Intermediate
 
Joined: Nov 2012
Posts: 30
Likes: 0
Default 85 chip tuning

Hello I have an 85 vette with quite a few mods on it (cam,half dome pistons, race chip and racing exhost).

Im sure this question has been asked to death and I apologize if it has already been answered but I did search and found not a lot of info. At any rate from the mods that are currently on it it has a horrible lope at idle (sometimes will die).

I have some spare time a soldering iron and a spare laptop. Is there any way I can hook up to my ecu and tune it while driving or is this completely out of the question. Im extremely new to car computer tuning. I am a pc tech at a local shop so I can handle the learning curve. Just a nudge in the right direction.

Thanks in advance for all the help
Jake
Reply
Old Aug 23, 2013 | 02:20 AM
  #2  
Cliff Harris's Avatar
Cliff Harris
Race Director
15 Year Member
 
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Default

Your year has a couple of issues. One is that the data rate is limited to 160 baud. That is a big problem when trying to tune because you're only seeing snaphots of what is happening.

If you're serious about tuning I advise swapping in a 1227165 ECM, which was used from '86 through '89. It has a 8192 baud data stream. The swap is relatively simple and mostly involves swapping some of the pins in the ECM connectors. There are several sites online that spell out what is required.
Reply
Old Aug 23, 2013 | 04:12 AM
  #3  
vetteoz's Avatar
vetteoz
Safety Car
20 Year Member
 
Joined: Jan 2004
Posts: 3,556
Likes: 13
Default

Originally Posted by Jakez89
Is there any way I can hook up to my ecu and tune it while driving or is this completely out of the question.
As noted there is no support for the slow , one year only '870 ECM in your car.

Once you have upgraded to the later '165 ECM
http://www.eecis.udel.edu/~davis/z28/ecm_swap/

then you can buy this device
http://www.moates.net/ostrich-20-the....html?cPath=95

" a emulator" that takes the place of the memory chip (memcal ) in your ECM and allows real time ,as you drive adjustments and tuning from a laptop
using cheap ($30 ) software

You also need this adapter
http://www.moates.net/g1-memory-adap....html?cPath=31

which replaces the stock memcal in the ECM and allows the ribbon cable supplied with the Ostrich unit above to connect the ECM.

FWIW,
The '165 MAF ECM (# 1227165) was used on many GM vehicles

http://home.earthlink.net/~cliff_har...age/usage.html

Only the tune on the installed memcal determines what it is setup for ; do not pay extra for a "Vette" '165 ECM
Reply
Old Aug 23, 2013 | 10:04 AM
  #4  
Jakez89's Avatar
Jakez89
Thread Starter
Intermediate
 
Joined: Nov 2012
Posts: 30
Likes: 0
Default

Hey Thanks a lot Cliff Harris and Vetteos I've at got a plan of action that I can move forward on and maybe finally get my idle a little smoother.
Reply

Get notified of new replies

To 85 chip tuning





All times are GMT -4. The time now is 12:13 PM.

story-0
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-1
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-2
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-3
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-4
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-5
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-6
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-7
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-8
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-9
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE