Q Re Ad for 1990 Supercharged Avanti Convertible

[Rich]

I thought I've done quite a bit of Avanti history reading/investigating, but this was a new one for me. I'm wondering if anyone can illuminate the issue.

In Hemmings is a 1990 Avanti Convertible with a supercharged Tune Port Injection engine - very sweet. I did not know anything other than 4-doors were licensed in 1990. I knew of the 15 Convertibles for 1991 and however many there were in 1989. If they did sell something other than 4-doors in 1990, what were they and how many? Anyone?

The second surprising thing about this ad is that Avanti sold a supercharged engine. Anyone have any knowledge or information about it?

Thanks,
Rich

[stude dude]

I thought I've done quite a bit of Avanti history reading/investigating, but this was a new one for me. I'm wondering if anyone can illuminate the issue.

In Hemmings is a 1990 Avanti Convertible with a supercharged Tune Port Injection engine - very sweet. I did not know anything other than 4-doors were licensed in 1990. I knew of the 15 Convertibles for 1991 and however many there were in 1989. If they did sell something other than 4-doors in 1990, what were they and how many? Anyone?

The second surprising thing about this ad is that Avanti sold a supercharged engine. Anyone have any knowledge or information about it?

Thanks,
Rich

I think its a 1989 model thats been updated with a few mods. Everything about the car says 1989. Looks pretty good though.

[studegary]

AFAIK, only four door sedans were made for the 1990 model year. This is probably a 1989 the was left over and first titled during the 1990 model year. What is the serial number? That should tell the story.

[Rich]

Gary - they state the "stock number" as #1003. Not sure if that represents the Serial Number or not, but it's pretty close to what it could be. I've left a message, hoping to get a call back to find out more. If the current motor is post factory build, I'd love to track who did it and get specifics on the supercharger set-up, ECM programming, etc. Anyone know if Avanti installed a supercharger set up after the LSC and anniversary models?

Rich

[studegary]

Gary - they state the "stock number" as #1003. Not sure if that represents the Serial Number or not, but it's pretty close to what it could be. I've left a message, hoping to get a call back to find out more. If the current motor is post factory build, I'd love to track who did it and get specifics on the supercharger set-up, ECM programming, etc. Anyone know if Avanti installed a supercharger set up after the LSC and anniversary models?

Rich

That is probably a stock number and not a serial number. If it is a true serial number, it is a 1990 number, not a 1989 number. Maybe it was a 1989 left over at the factory and it was titiled as a 1990, with serial number plate, by Avanti. If so, it is news to me and also makes the number of four doors even smaller.

[Rich]

I doubt that it is a 1990 Serial Number, unless Avanti used a different prefix for the Convertible. AAU-1003 is a 4-door model owned by Arnold Hoskovec from Bates, City, MO (Arnold also owns 1006 and used to own 1077). I'll email John Hull to see if he has additional info.

Thanks,
Rich

[N8N]

I seem to recall some discussion about the supercharged engine being a very limited production option and also there having been issues getting the engines to run correctly, but I don't recall where I read this so it might be somewhat anecdotal. I don't think it was here; might have been some Avanti-specific web site.

nate

[grobb284]

If the current motor is post factory build, I'd love to track who did it and get specifics on the supercharger set-up, ECM programming, etc. Anyone know if Avanti installed a supercharger set up after the LSC and anniversary models?

Rich

Rich, a similar setup can be accomplished with a TPI and Paxton supercharger utilizing a Holley Commander ECM and a 2 bar reading from a Buick GN. This makes all the sensors GM. By the way, the Holley ECM may be able to handle up to 3 bar.

The Holley ECM is easy to program, and fired the engine the first time.

[Rich]

This has me very interested! I was not aware of the Holley Commander 950 ECM, but a few minutes reading Holley's website, it seems it could replace my GM (#730) ECM and allow more precise fuel maps than what I have. Are you using this setup? Do you have a custom program or are you using one from Holley? Do you know if it's a plug-and-play solution for a GM TPI ECM? Guess, I should call Holley and discuss my particular application. Thanks for letting me know...

Rich

[grobb284]

This has me very interested! I was not aware of the Holley Commander 950 ECM, but a few minutes reading Holley's website, it seems it could replace my GM (#730) ECM and allow more precise fuel maps than what I have. Are you using this setup? Do you have a custom program or are you using one from Holley? Do you know if it's a plug-and-play solution for a GM TPI ECM? Guess, I should call Holley and discuss my particular application. Thanks for letting me know...

Rich

I used it on a TPI with SN60 setup. The Holley Commander 950 comes with an assortment of programs that you can load, and once running, can modify. I don't know if you can use your existing harness, I purchased a harness with it from Holley. Contact Holley for more information. Their chief engineer for the ECM participates on the Chevytalk forum, in the ECM catagory. He is accessible, and quite helpful. That was one of the reasons I went with the Holley. You might go to the Chevytalk forum, just to garner more information. He also answers questions about other ECMs. I was not dissapointed the the Commander 950, I was quite pleased. There is newer technology now, but more expensive.

[studegary]

I doubt that it is a 1990 Serial Number, unless Avanti used a different prefix for the Convertible. AAU-1003 is a 4-door model owned by Arnold Hoskovec from Bates, City, MO (Arnold also owns 1006 and used to own 1077). I'll email John Hull to see if he has additional info.

Thanks,
Rich

You didn't give a prefix with the 1003 number. Aha! - I see that you are pointing out that sedan 1003 is accounted for. I thought that the serial number prefix was RBK.

[8E45E]

I seem to recall some discussion about the supercharged engine being a very limited production option and also there having been issues getting the engines to run correctly, but I don't recall where I read this so it might be somewhat anecdotal. I don't think it was here; might have been some Avanti-specific web site.

Nate, that was a feature of the '25th Anniversary' model that appeared in 1988, of which very few were produced.

Craig