Euro 1977 308 GTB Steel -vs- US, 77 GTB Steel body

My questions are how the 1977 Euro version compares to the US version. Aside from the Euro GTB having the dry sump motor (F106 A) type. and the US (F 106 B) wet sump type motor. Is it true that both motors share the same Euro type aggressive cams for 1977?

Next is it true that there are about 250 lbs. or more in weight differences between the two? If so, can you easily modify the US version to get very close to the Euro spec car in weight? Would it just be a case of changing out the US spec bumpers, their braces, etc for the Euro type bumpers? Also changing the exhaust system, and any air pumps for the non - Cat 1977 US version?

Thank you, I would appreciate any insight, and advice.

 

Can't comment on the specific differences between US and Euro version, but I've been keeping track of weight deltas in changes I've made, and thus far have removed over 200lbs (more than I weigh) from my US version '77, not counting the spare wheel. See the attached .pdf of my excel sheet.

 

Steve,
Where’d you source your Ti wheel studs and lug nuts? This is on my diet list as well.
- Dave

 

This is a great resource, and I'm compiling my own list of weights as I remove/replace parts. I also went to an aluminum radiator, but I forgot to weigh the stock one - is your 23lb weight for the oem rad something you recorded yourself, or did it come from another source?

 

Don’t forget the extra steel in the doors

 

Dave-they came from AcerRacing.com. You need the 70 and 80mm lengths due to the difference in brake disc top hat thickness front/rear.
I didn't change to the Ti studs to save weight, I simply wanted studs/nuts, and found these. Price per pound saved is not very cost effective
They also sell Ti wheel bolts in Ferrari spec.

 

The weights listed I measured myself, most using a 100lb shipping scale (hence the round numbers), a digital bath scale for a couple of items, and a small digital postal scale for the wheel studs/nuts.

 

This is what my US '77 weighs. No spare tire, Aluminum radiator, no smog pumps, euro GT4 Ansa exhaust, US bumpers pushed in.

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For people looking at Ti wheel nuts, In some cases they can be heavier than aluminum; I bought a set for another car, and when I weighed them against a set of aluminum nuts, the aluminum nuts were actually lighter. I've found this to be the case in other small-part applications (for bicycles, for example).

 

Lug nuts?
Man, you’re a braver soul than me.
- Dave

 

WOW!! This is outstanding data! Thank you. Have you noticed a performance increase?

 

I’ve converted two US spec 76-77 GTBs to Euro bumpers. I weighed them using corner scales that I know for certain were dialed in accurately.

The engines are essentially the same these years, euro cars just had no sound deadening in the airbox while US cars did, removing that frees up some air flow, cams and compression are same. The dry sump engine is actually a bit heavier due to the tank and oil pump.

The US cars rear and front structures have a bit more metal for bracing the impact bumpers, I’d say it’s around 20lbs total, mainly at the rear. The additional steel in the US doors for side impact weighs very little, maybe a pound or two as it’s just a piece of thin gauge steel bent in a U shape and tack welded to the inside of the door.

parts removed and replacement:

-Two air pumps and plumbing (around 50lbs)

-Bumpers and front bumper shocks (rears bumper shocks were kept but pushed in) and replaced with fiberglass units which are actually a bit lighter than Euro bumpers. Net difference is just under 100lbs.

-thermo reactor muffler (weighs some 100lbs) replaced with stainless Nouvalari on one and a custom unit on the other. Net difference about 70lbs.

In the end both with about half a tank of fuel and spare tire weighed in at about 2850lbs. The net weight removed was on the order of 220lbs so it does make a noticeable difference in how they drive once the conversion is complete.

 

This is great information! My target car was a Euro 1977 308gtb. However, given this very interesting information on weight saving measures I am reconsidering, and just going for a US spec car! Does the Euro dry sump motor add any performance advantages? Last question: What does a 1977 Euro steel body 308GTB actually weigh?

Thank you all very much! This has been huge!!

Sincerely

 

Intersting. How much fuel was in the car? Using my Proform scales, I got 2818lbs with the fuel gauge showing just over half, so about 60lbs of fuel.

 

I wrote this here before sometimes but my '78 US GTB, when imported and registered was weight at 420KG or 3130 lbs , probably with half a tank of fuel.

After my race-car conversion it was weight again on the same scale and it brought 1060KG or 2336 lbs, also with half a tank of gas.
I added some weight to in a full steel FIA roll cage and a turbo-setup

Sure i did some odd things but there's an awful lot of weight in these cars when stock. Btw the car is still registered and road legal

 

Steve,

About 1/4 tank. The scale was at the dragstrip.

 

Wow! This has been very informative, and enlightening. I have a new perspective on my target 308gtb. This opens up much more possibilities!
Thank you all.

 

Do you have pictures of your car? What were the heaviest items you removed/replaced?

 

the heaviest single items where the front and rear bumper, each about 18Kg and the doors, each about 37kg
both where replaced by very light-weight race parts

For the rest it was a vast variety of items I replaced, or removed.

there's a complete thread on f-chat. I even think it listed all items there.
But in total 360KG, or 793 lbs was removed . Needless to say, it transformed handling.


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No, not per se, but the dry sump system does eliminate the wet sump cars' infamous issue with oil starvation in RH corners. As the former owner of multiple cars with wet sump transverse engines - that never experienced starvation issues - it was shocking to me how easily the 308 could be goaded into starvation. Fortunately, aftermarket baffles are available to help control it and I've read positive feedback from those that have installed them.
Were I keeping my '83 GTS I'd be installing one too, but a dry sump car sort of fell into my lap last year so the spyder has to go.
Best of luck in your GTB search,
- Dave

 

The old racer's adage is don't look for a place to save a pound, look for sixteen places to save an ounce.
If I can get half that amount of weight out of my car I'll considered it a job well done; 800 lbs is almost unfathomable.
- Dave

 

Indeed it was an exercise..

Painstakingly going through every bit and piece. But it was well worth the effort. And it was fun!
I was not only looking at the small stuff only btw. As example, i replaced the complete front clip and rear-end for glass fiber parts.
There's still some more weight that can be taken of, but that would mean spending hundreds, or more per kg. In the end I was happy with the result, It would have been nice to bring it under 1000kg however. Just for the fun of it.

The turbo brought the output close to 300bhp so the power to weight ratio now improved to about half of the original car. Also part of the fun

 

What was the resulting front to rear weight balance?

 

Don't forget to remove that chunk of ugly laminate plywood under the rear boot carpet.

 

The rear laminate is heavy. Maybe only on USA cars(or catalyst ones)? The 1980-85 cosmetic door pockets are also very heavy. Like 6 lbs each. It's either solid wood or solid fiberglass.