Greetings, I am new to this message board but have already found tons of useful information!
Anyway my project is a 1969 Opel GT. For those of you that don't know the US model GT came in two engine sizes 1.9L and 1.1L. The 1.1L can regularly get 50-55mpg and the 1.9L was about half that. The 1.1L is significantly lighter, everything from the radiator to the motor to the rear axle is smaller and lighter.
My goal is to break 65Mpg in mixed driving. There are several things I am going to modify that I believe will get me to that number. The first is the rear axle ratio. I am changing the 4.11 rear axle with a 3.89 from another model Opel, I have considered adapting a 5 speed manual (currently 4sp man) but I think the new rear end will give me the proper OD ratio. I am building a programmable FI system, the stock engine has two hard to adjust carburetors. I will also have a custom fabed exhaust system. I have not done a cost benefit of raising the compression but I may raise the compression. Beyond that the only engine modification I may experiment with is different cam ratios, but because I would have to have these custom made as there are none readily available, this is last on my list.
I also plan to do as much weight reduction as possible. Replace the metal hood and belly pan with fiberglass. Replace the steel wheels with light weight aluminum. Replace the steel radiator with modern aluminum. I don't know how heavy the stock seats are but I am guessing I can find lighter modern seats. Remove any unnessicary interior pieces.
I don't have the shell of the car yet but I do have the complete drive train. This weekend I am going to be tearing down the engine to rebuild it. If anyone is interested I will upload some pictures of my progress.
Yes I think this is a great project I am currantly restoring a 1969 opel gt 1.1 and am trying to get max mileage from it. Got it 2 years ago on ebay. Will be interested in things like the light weight rims Good Luck Also you can get fiberglass shells i think for entire body Might do a google search for it. Later opeldog52