Worth Repowering my 1991 Convertible?

[Stacey]

Have a 48,000 mile 1991 Avanti Conv that is in really nice looking shape. Has a few minor issues like the a/c doesn't work, but overall is really nice. It has the 305 slug of a motor,  that runs perfectly just not really powerful and lacks the get up and go. I've toyed with the idea of pulling that 305 and dropping in a 350/or 383 chevy with some real power, changing the rear axle ratio and making it a fun hot rod. Need some opinions on if this will kill any resale value or ??  make it more desireable. As it is it gets a lot of thumbs up and is fun to drive, as it is quiet and comfortable and no rattles or odd noises. 

[studegary]

I do not think that the change would have much of an effect on the value of the car in either direction.  Some will like the change and some won't.  If it runs good, I would leave it alone and just enjoy it for what it is/does.  Part of the answer lies in how long you plan on keeping the car.  It is built to be a cruiser, not a sports or muscle car.   

[mfg]

Interesting question!...I agree the 305's run OK, but really don't have much "snap"!......In my opinion, the Chevy 350 seems to be the replacement engine of choice for later Avantis....and, if anything, I feel a fresh 350 would only increase the value of your Avanti!

Unlike the Studebaker Avantis, "numbers matching" original engines don't seem to mean much on the later cars, and, I suppose if you wanted, you could save the original engine anyway!

PS.........Your Avanti is really gorgeous!...I'd sure like to own an Avanti convertible someday!....Good luck!.....Ed

[Gunslinger]

It's your car...future resale value is your decision...not ours.  Post-Studebaker Avantis don't usually see much, if any difference in values with an engine change as long as it's done correctly.  A crate engine 350/383 would essentially be a drop-in with little modifications necessary...if any.  If you really want to make it special...get a GM LS-based engine installed.  While there would be some mods necessary it's been done before so it's not an unknown quantity...they're plentiful and easily found...less weight and outstanding performance.  

 

[mfg]

8 minutes ago, Gunslinger said:

  If you really want to make it special...get a GM LS-based engine installed.  While there would be some mods necessary it's been done before so it's not an unknown quantity...they're plentiful and easily found...less weight and outstanding performance.  

 

Mods like this would appeal to some....however, would be questioned by most.....Going with a traditional 350 CI small block Chevy keeps the originality of this nice Avanti convertible intact at resale time.

[Avanti83]

Personally, I'd drop in an LS but the most cost effective option is a crate 350/383. If you plan this option, I'd use the original computer control and find someone that can burn a new performance chip for the ECM. The current 305 chip will be underwhelming in it's control of the engine and possibly make it run just crappy. There used to be a number of folks that burned chips but a Google search should get you there. Remember you have basically a Chevrolet engine control system so whatever fits them should work in yours. I uses the Camaro ARAP control code in my 91 350 I put in my 54 Stude and it runs well using the OEM harness and computer modified for the setup.

Please don't convert to a standard carb setup, if you do you will need to change the distributor and buy a controller for the transmission which is a pricey option. 

It's a nice car and deserves to perform as well as it looks.

Edited August 8, 2020 by Avanti83

[Footer]

I guess a question I would have is at what point does the “make it special” factor get outweighed by the cost factor?  My 305 certainly is no hot rod, but I wonder if the cost of an LS vs a crate 350, say 330 hp or so would make it that much more fun. Kind of limited by tires, suspension, and brakes at some point,  but a LS would look good at show. I realize there is probably no right answer for this,  but  how about some of you with high hp conversions weighing in if you feel like you got a good bang for your buck. Thanks, Mike

[Stacey]

I do like the car, as I said it is a nice cruiser and is Quiet & Smooth driving, my wife likes that fact. I'm pretty sure it would not spin the tires on gravel and for sure you need to plan any accleration into traffic. It is a dog.,but looks good. I've kicked around selling it and buying something else already repowered and made quicker. Will attempt this week to investigate with the local hot rod shops to the cost and effort needed to swap in more power.  As it is it runs as well as it can and has not given me a lick of problems power train wise. Have upgraded the radiator and now it runs cooler..  

[Avanti83]

1 hour ago, Stacey said:

I do like the car, as I said it is a nice cruiser and is Quiet & Smooth driving, my wife likes that fact. I'm pretty sure it would not spin the tires on gravel and for sure you need to plan any accleration into traffic. It is a dog.,but looks good. I've kicked around selling it and buying something else already repowered and made quicker. Will attempt this week to investigate with the local hot rod shops to the cost and effort needed to swap in more power.  As it is it runs as well as it can and has not given me a lick of problems power train wise. Have upgraded the radiator and now it runs cooler..  

You are asking the right questions. If you don't do your own work then turning to the experts is the best course of action. As far as selling and buying all over, you know this car, whereas another vehicle has unknowns. Your vehicle with a professional upgrade should give you the best of both worlds. I could probably take a wild guess at pricing but getting the numbers from your local pros will top any prices we supply.They can also discuss the SBC vs LS upgrade nuances.

Avanti, Bob

Edited August 10, 2020 by Avanti83

[studegary]

IMO, if you have to pay to have all of the work done, either live with your car as it is or sell it and buy something else.  If you do farm the work out, at least have "time is of the essence" in the contract with a reasonable end date.