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Swapping 85 ECM to newer?

LD85

Well-known member
Joined
Nov 14, 2002
Messages
83
Location
Indy
Corvette
1985 Coupe
Which is the best swap from an 85 to a what? I dont want to swap any wiring just want some faster computation.
 
Unfortunately that is a problem. The ECM in the 85 has a 160 baud rate , the next upgrade is to one that has 8k speed and needs rather extensive rewiring to make it work...the following site has a ton of info concerning the swap....it is for a Z28 but you will get the idea. Actually you will see that the Z has the same ECM as the 85 vette and the upgrade requires changing the connectors and some repinning as well as getting a new eeprom for the newer ECM. It looks like a decent winter job...good luck...

http://www.eecis.udel.edu/~davis/z28/ecm_swap/
 
you dont want to swap any wiring? Well then your not gonna get a different computer in that 85.

There is NO WAY you can put a different computer in your car w/o swapping at least one wire.

The easiest conversion is to put in a '165 ecm (still maf).

I run a gm '7730 speed densit set up (map sensor) the conversion is not easy, but not hard. You can do it in a day if you stay with it. But my car is no where near stock, despite my stock signature!

Why do you want to swap ecm's? If you car is stock and everything works fine, then I say leave it alone. IMHO your not gonna run any faster.

check out http://thirdgen.org under the diy section and their prom/ecm swapping section (I forget what its called)
 
ld85, I know who you are! You are putting in a 406 in your 85.

Lets talk ecm swaps......

How much do you want to spend?
Do you really not want to do any wiring moving/splicing?
Do you want speed density or maf?
Do you want the ecm to easily manage changes as time goes by?
 
If you will go to the site I referenced in the above post you will find there are various reasons to switch ECM's. Faster processing time is one as well as a faster sampleing time for those interested in what the various sensors are doing in any given situation. The site shows exactly how to upgrade the ECM and is pretty straight forward. Don't have to be a brain surgeon to see the difference between 160 bits per second versus 8 thousand bits per second. Also there are several sites and or threads where this has been done and shows greater performance.
 
Eagle85C4 said:
Unfortunately that is a problem. The ECM in the 85 has a 160 baud rate , the next upgrade is to one that has 8k speed and needs rather extensive rewiring to make it work...the following site has a ton of info concerning the swap....it is for a Z28 but you will get the idea. Actually you will see that the Z has the same ECM as the 85 vette and the upgrade requires changing the connectors and some repinning as well as getting a new eeprom for the newer ECM. It looks like a decent winter job...good luck...

http://www.eecis.udel.edu/~davis/z28/ecm_swap/

OK I will check this out in a few hours when I have some quiet time, and I guess I was just hoping that I would not need to swap pins etc. I thought someone on the other board went from an 85 to an 86 ECM and just swapped them out!?

Hey TNTCORVETTE! yes I am putting the 406 in my car, and have decided on the minram setup with the TPIS 409 Cam with retro rollers and stamped roller tips,, all from TPIS.

If I an going to have to do reprogramming then I really want to do it with an ECM that I can actaully communcaite with. So if I have to swap pins I guess I will.
 
if thats your final combo, then the only way to go is speed density and that means either after market or the gm '7730 swap. If you do the '7730 swap the instant/average mpg wont work but thats no big deal.

Im gonna ball park the '7730 swap to be ~$100, less the chip. If you decided to do your own chips, you need a memcal adapter. I have one I can sell you for the '7730 swap. Let me know
 
LD85 said:
yes I am putting the 406 in my car, and have decided on the minram setup with the TPIS 409 Cam with retro rollers and stamped roller tips,, all from TPIS.

I would spend the little bit extra and get the Comp Cams Pro Magnum rockers (full roller) 7/16" and be sure the heads have the 7/16"

You can get those from TPiS as well.
 
Jeff, will they fit under the valve covers or do I need to mod the valve cover?

Also, do you know of anyone running the 409 TPIS cam on an L-98?
 
LD85 said:
Jeff, will they fit under the valve covers or do I need to mod the valve cover?

Also, do you know of anyone running the 409 TPIS cam on an L-98?

Drip Tabs will need to be trimmed but since you have perimeter style covers you should be okay..

as for the ZZ409, I just bought one off of someone and will be installing it in Feb/ March.. if USPS ever delivers it.

I did know someone who had a Miniram and 409, I know it worked well.. but don't remember the #'s for it..
 
LD85 - I have the Mini Ram II/ZZ409 cam combo on my ZZ4 crate engine I put in last spring. The heads are the stock 113 D ports as installed on the ZZ4 crate engine. With full exhaust treatment a 52MM TB cut lid and foam filter it all works pretty well with my 89 MAF set up and a chip Jeff burned for me. It still needs work at idle and low speed but runs well to 6,300 plus. I'm now in the process of putting on a worked set of 113 D port heads to make better use of the cam and still try to pass emissions using only the main cat. The ZZ409 cam is a single pattern cam. It has the same exhaust lobe as the ZZ9 but has a bigger Intake lobe. I believe this set up works well in a head like the 113 casting with a great exhaust ratio. The basic specs are .520 lift (Intake and Exhaust) with 1.5 ratio rockers/duration at .050 of 226 degrees (Intake and Exhaust)/112 degree lobe separation. Its the GM Hot cam with a tad less gross lift (but only have to use 1.5 ratio rockers) but with a bit more intake duration.

I agree with Jeff you should at least put on roller rockers (I run the bowtie self-aligned 1.5 roller rockers) BUT what heads are you installing on this 406 monster? The ZZ409 will be toned down quite a bit with those cubes and you would probably at least want to go with a 1.6 rocker ratio as you need a lot more head flow than a stock 113 casting would provide. On my stock setup with stock heads and injectors etc it's very streetable with no vacumn problems.

Phil (aka 89ZZ4)
 
Well when I talked to Chris at TPIS today they stated that the 190 or 195CC head is what would be best to help promote low end torque and still top out at 5800 RPM.

Another guy I know (Ol RJ) went from the 195's to a 210 CC head and picked up @ 30 HP if I rememebr correctly.

Dont know which exact head yet just that they will likely be Canfield or Dart heads, unless a set of 195-AFR's turn up between now and the end of February.

I have not seen many people running the ZZ409 cam but the numbers were very very impressive on the 409/ LT-1 which TPIS built with this cam, 528-TQ at 4750 RPM and 523-HP at 5750RPM!
 
i just finished swapping my 85 over to the 165 ecm,,,its actualy really easy,,,there are a few things posted on the above site the are not correct for corvettes,,,,if you decide to go to the 165 i can email you simple instructions,,,,,,i did mine in less then a hour :beer
 
I would be interested in see what you have ...if nothing else just for reference...thanks...
 
There's a lot of info out there so ask lots of questions. I was just looking at the TPIS web site and saw that they had a 383 build up with the ZZ409 cam/TPIS-AFR Heads to get over 500 HP but they used the 1.6 ratio rockers which would give a gross lift of over .550. I like the idea in their 2003 catalog you can get the Mini Ram II with a bigger port size to match your heads. The one I have is matched to the smaller 1204 Fel-Pro gasket size which is the direction I am heading as my new heads are being ported to the 1204 size only with larger stainless valves with 30 degree back cuts, bowl work and springs that will handles upper five gross lift with a reasonable seat pressure. I want a reliable street motor in the 400-420 flywheel HP range that will hopfully pass emissions in IL and will keep up with the latest Rustangs etc. while looking like a nice harmless stock 89. I want a very balanced package that works well together. I already have the Z51 package, six speed, BFG KD's, a chamber brace and brake bias spring so after the heads is the rear gear. A fun street machine for summer running without spending a bundle. It's a never ending journey.

Phil (aka 89ZZ4)
 
do you know anyone in Illinois who has passed emissions with the ZZ409 cam?
 
Swapping 85 ECM to newer

Hey , Anyone swapped the 85 ECM to newer ECM ? If so anyone have directions ? Repinning locations , Etc ?
 
i just finished swapping my 85 over to the 165 ecm,,,its actualy really easy,,,there are a few things posted on the above site the are not correct for corvettes,,,,if you decide to go to the 165 i can email you simple instructions,,,,,,i did mine in less then a hour :beer
If possible could you send me copy of the I instruction
 

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