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Unichip

jstkrsn

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59
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Parrish, FL, USA
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1992 LT1 White Conv.
Does anyone have any experience or know anything about the Unichip programmable computer for OBDI cars. It's very expensive but it will reprogram like they do with the OBDII cars(ie Hypertech Power Programmer). It fits in between the ECM and the Engine. The stock chip remains intact. It's like $600 plus programming on a dyno @$80/hr for 3-4 hours.
 

Edmond

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2003 Z06
Wow, you're looking at a minimum of $840 for that chip! I'm sure someone in here knows a high roller who has had that done.
 

JT ZR-Won

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Bradenton, FL
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'90 ZR-1 #3010
I really can't see it being that much better than a custom burnt chip. You can take your car to a tune shop and have one custom made to your cars specifications for probably half that price.

Jay
 

-=Jeff=-

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Bartlett, IL. (Chicago Suburb)
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JT ZR-Won said:
I really can't see it being that much better than a custom burnt chip. You can take your car to a tune shop and have one custom made to your cars specifications for probably half that price.

Jay

or do it yourself for a lot less
 

jstkrsn

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Messages
59
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Parrish, FL, USA
Corvette
1992 LT1 White Conv.
Jeff, where can you get the chip burner and knowledge to do it yourself. I watched a guy burn one for me in 1987. It didn't look like much of a machine. Just a little box you put the chip in. Unfortunetly he doesn't do it anymore (he now works for Callaway in Conn). But where can you get one, and directions. Would love to just do it myself.
 

WhalePirot

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SoCA
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1984 White Z-51/ZF6-40/Shinoda body
hardware=easy - knowledge=priceless

The hardware to burn a chip is not much. The knowledge about spark advance, the fuel table, and all else controlled by the ECM, plus the instrumentation to see what the current chip is commanding, is quite another.

This is as risky as redoing the BIOS on your computer, but a lot more complicated. One had better understand quite a lot before messing with it. Many seasoned Vette techs, cannot re cut chips.
:w
 

-=Jeff=-

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Bartlett, IL. (Chicago Suburb)
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1990 ZR-1
a good Star tis www.diy-efi.org

also on www.thirdgen.org there is a good PROM burning article.

Most people use the hardware from Xtronics I have yet to get that one, I have an older programmer I got really cheap and seems to work for now

I am doing the custom PROM for my 89.. I am using 1991 code since I have the 1991 dash and ECM and have left the stock timing tables alone but have been concentrating on getting the fuel mixture right.
 

jstkrsn

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Messages
59
Location
Parrish, FL, USA
Corvette
1992 LT1 White Conv.
You're right Mike, I looked at the Web sites that Jeff Posted, and that stuff does look pretty complicated. I've got a lot of reading to do on this one. May not be worth the trouble to do myself. Just pay the piper.
 

-=Jeff=-

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Bartlett, IL. (Chicago Suburb)
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jstkrsn said:
You're right Mike, I looked at the Web sites that Jeff Posted, and that stuff does look pretty complicated. I've got a lot of reading to do on this one. May not be worth the trouble to do myself. Just pay the piper.

Why do you want to reprogram you ECM? If it is just for the fans, I could do that for you. Looking at yoour Signature with the mods you listed that UNICHIP is not worth the $$$
 

jstkrsn

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Jun 3, 2002
Messages
59
Location
Parrish, FL, USA
Corvette
1992 LT1 White Conv.
Jeff, I'm just looking for a chip that does something besides just turning on the fans early. And I don't really care about that either. I've put switches in my 86 Vet and 87 Firebird that did that. But the Hypertech chip I have doesn't seem to do any good except turn on the fans. The chips I had in the 86 and 87 you could feel the difference immediately. Changes I have sitting in the garage right now are a 3.07 axel to replace the 2.59, and SLP shorty headers. I also plan on some kind of ram air and 1.6 roller rockers later this year. I just happened to see an ad for the Unichip so I started to check it out. Sounds like the only way to go is to finish all the mods and then have a chip burned on a dyno. I think that's the only way you would get it all right. So there must be someone in SoCal that does that. Anyone know of someone?
 

-=Jeff=-

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WhalePirot

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1984 White Z-51/ZF6-40/Shinoda body
I bet I have $1k in my chip. I posted all this on another thread.

I looked for 4 years to find someone in SoCal to do my chip on a dyno. Ron Z. did a friend's chip, for a 406 that I copied. His runs okay, but 'his' chip made my car run terribly; very, very rich. I saw the Z-man burning a RPOM for the Boydster and a Suburban, on a dyno in Whittier, years ago. That relationship has evaporated and I am not sure 'Z' does chips anymore.

Gary L. and Jack did my chip, based on a 427 they had done earlier. My car runs like nothing I have ever driven before! WOW! (and it passed SMOG easily). Gary did it manually, w/o a dyno, and is not interested in doing another.

I wish I had an answer, but definately check on this before you go with a cam that will lower your MAP, such that the computer enrichens the mixture. I put up with this for years, always irritated at the richness and sweating the SMOG check. It never got solved on my L83 engine.

Good Luck! Call me for a tour of this WILD '84!

:w MIKE
 

jstkrsn

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Jun 3, 2002
Messages
59
Location
Parrish, FL, USA
Corvette
1992 LT1 White Conv.
I talked to Ron Z, He wants $275. The thing that surprised me was he said he actually retards the timing 0.5 degree instead of advancing it. He basically adjusts the fuel mixture. He feels that the timimg is pretty much optimized already. Maby he's right, I don't know.

Jim
 

-=Jeff=-

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Messages
909
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Bartlett, IL. (Chicago Suburb)
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1990 ZR-1
jstkrsn said:
I talked to Ron Z, He wants $275. The thing that surprised me was he said he actually retards the timing 0.5 degree instead of advancing it. He basically adjusts the fuel mixture. He feels that the timimg is pretty much optimized already. Maby he's right, I don't know.

Jim

He is right on the Timing. I am running the Stock 91 timing tables in my car. I am just tuning the fuel.

Now on the 89-older I have added timing and gotten great results. Those old MAF cars love timing
 

Edmond

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Location
Louisiana
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2003 Z06
Vettelt193 said:
On LT1/4 cars timing is very optimized... this is the only good thing about having an opti-spark

And that's opposed to the traditional distributor right? The opti-spark has something to do with lasers right?

Some people I know absolutely dread the opti-spark because of it's cost to replace!
 

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