Alfa Romeo Forums banner
41 - 60 of 78 Posts

·
Registered
Joined
·
58 Posts
You see I'd prefer that somebody created a GTA replica out of a 4 bolt front cross member as you will still get the GTA driving experience, but very easily identifiable as a fake ... but I know I am a different planet to you Steve :)
All 848xxx GTA's have 4-bolts... so this won't help you out in identifying a replica as fake ;-)

Dont' forget that this forum contains a "GTA observatory" so any fake GTA that pops-up will soon be noticed :cool:

But if you want to pick a starting point for builiding a GTA "look a like" or "replica"... I'm with Steve, value wise it's better to start with a car from the same period (pre sept. 1967).

The chances are greater that it contains all the right bits and pieces for builidng a car that fulfills FIA appendix K for 1965-period racing if you want to take that option (or leave that option open).
 

·
Registered
Joined
·
5,035 Posts
PETE, If I ever get my 64 Sprint GT to more or less look like a GTA from 50 feet, it will not be to any FIA spec, it will just be for my pure pleasure and if someone here in North America should want to Vintage race it later, FIA rules are not an issue as far as I know. So you won't be crushing my dream. now or later.

Cheerfully

Ken
 
  • Like
Reactions: brad fischer

·
Administrator
Joined
·
15,955 Posts
Ken, Are you going to alloy body your Sprint GT?

You already have 3 GTAs, confused. And yes of course I don't ever want to see anybody's dream crushed, but shouldn't our primary goal as Alfisti be to save the surviving original cars?, not post incredibly detailed instructions on how to make the most authentic forgery
Pete
 

·
Registered
Joined
·
5,035 Posts
Pete, I am against forgery, always have been. I would only alloy the door skins, boot lid, license light plinth and maybe hood on a Tribute GTA.

Ken
 

·
Administrator
Joined
·
15,955 Posts
Pete, I am against forgery, always have been. I would only alloy the door skins, boot lid, license light plinth and maybe hood on a Tribute GTA.

Ken
Beaut. So your car would never be in danger of my theoretical crusher :)

It is time I left this thread again, and for good
Pete
 

·
Moderator
Joined
·
1,241 Posts
Of course some owners of original GTAs are really not in a position to exercise their car/s as much as they would like. Of the 500 say GTA 1600s made there would be say as a guess 150-250 which are derivable, the rest say about 150 are sitting in garages and may take another 10 or more years to restore. (exact numbers are listed some were on Alfabb or in some of the recent books)
So sure building a Tribute GTA for the look or even an authentic GTA replica for the driving experience is one way original owners of GTAs can enjoy the GTA experience while they wait for their GTA to be restored or those with running cars with out risking their original GTA car/s collection on the track/road.

If you don't have an original GTA a Tribute GTA for the look may suffice but if you want an authentic GTA driving experience it has to be an authentic GTA replica.

I did have another thought for those whom still want the authentic GTA driving experience, but want a second choice with regards to brakes. Since the GT Veloce 1600 group 2 cars had numerous GTA options in 1966 as part of their homologation, they had the ATE brakes in 1966 while the GTA had to wait until 1968. From a technical start point, you can use a GT Veloce 1600 group 2 car with it's ATE brakes to still build an authentic 1968 GTA replica as per 1968 FIA rules. This would give you an authentic FIA 1968 GTA replica. This 1968 version probably won't be allowed under in the latest FIA appendix K for 1965-period rules for racing.

So the check list for donor cars is
To participate in FIA appendix K for 1965-period use a Dunlop braked GT Veloce 1600 Group 1 car or a GT Sprint 1600 or back date brakes on a GT Veloce 1600 group 2.
or
A GT Veloce 1600 group 2 car with it's ATE brakes to build an authentic 1968 GTA replica as per 1968 FIA rules.

The GT Veloce 1600 group 2 cars with their ATE brakes could be an intermediate step to building the easiest car first an authentic 1968 GTA replica as per 1968 FIA rules using the GT Veloce 1600 group 2 ATE brakes, then if you choose back date the ATE brakes to Dunlop to go racing under FIA appendix K for the 1965-period.

In some society somethings tend to be sent to the crusher rather than re-purpose it. Unfortunately many cars like the GT Sprints 1600 and GT Veloce 1600 and others where destroyed and were sent to the crusher for reasons I've mentioned before. For those cars that remained I'm sure we know of a story where a car was pulled out from under trees and from open fields and the like riddled with rust and missing many parts. Some times these cars were cut up and sent to the crusher as well or sliced up and used to fix other cars. Other times we as enthusiast stored them thus saving them.

The authentic GTA replica will give you the authentic GTA driving experience and as a consequence the car will certainly be making a statement.

Steve
 

·
Registered
Joined
·
5,035 Posts
Ken, Are you going to alloy body your Sprint GT?

You already have 3 GTAs, confused. And yes of course I don't ever want to see anybody's dream crushed, but shouldn't our primary goal as Alfisti be to save the surviving original cars?, not post incredibly detailed instructions on how to make the most authentic forgery
Pete
BTW PETE. Ken does not have 3 GTAs.

Ken
 
  • Like
Reactions: PSk

·
Moderator
Joined
·
1,241 Posts
If you consider many GTAs had at least one race livery, those with two and three or more race liveries result in a dilemma even before the owner starts a restoration as to what colour and style to restore the car back to. Or say the owner is contemplating converting a stradale to a corsa. I'm sure questions discussed in another forum. Sometimes when the car is sold, the car is transformed by the new owner to another look paint scheme and there is nothing you can do about it.
I think there is a place for authentic GTA replicas either in stradale or corsa form.

Steve
 

·
Registered
Joined
·
5,035 Posts
Steve, I know what you mean.

Ken
 

·
Registered
Joined
·
7 Posts
Reading with interest. I am in the UK near the home of Aston Martins and have seen what some owners do to their cars with a £200k plus restoration. I would not worry about FIA regs etc if that's where you are going. Their cars always look stunning and the owners are proud of what they have also some of them actually drive them.
There are some of the best body builders in the world around here and would change panels from steel to aluminium with as many variations as you want you just have to get in line and your cheque book ready.
 

·
Registered
Joined
·
783 Posts
I'm sure that the original poster of this topic has long left this post and the endless .....advice (?).
As he stated in the very first thread he was going to have Alfaholics build him a car, and right there he has all the background knowledge and specification choices whether he chooses period correct or otherwise, and A/holics are in the perfect position to advise him with correct information for a period replica or retromod.
 

·
Registered
Joined
·
58 Posts
I do not think Alfaholics build "replicas", they do a wonderful take on a modernized GTA, ie lookalike but modern Alfa 75? running gear. Yes, it looks like a '65 GTA but much different.
Alfaholics can built you a GTA acc. FIA Appendix K... be it a 1300 or a 1600. They don't reproduce the historic GTA engine heads (twin spark) for nothing :)

You are confused with the GTA-R models they built... those are indeed based on modern Alfa 75 twin spark engines (if you want).
 

·
Registered
Joined
·
58 Posts
The main question is, did the stock GTA 1600 had a different roadholding capability that was noticeable on the road?

GTA's have special up-rights at the front...do they actually work different as their design intended?

Or in other words, can a Sprint GT keep up with a GTA if both had the same engine and drivetrain (gearbox, rear axle, wheels and tires)? (And driver...).
 

·
Moderator
Joined
·
1,241 Posts
A steel Sprint GT 1600 with an exact copy of the GTA drive train, using magnesium sump, cam cover, gearbox tunnel and diff housing would still be at least 180 to 200kg heavier than a GTA. That means it's spring rates would be different, so it would be different to drive. For the steel Sprint GT 1600 (or steel GT Veloce group 2) you would have to come on the brakes earlier and it would be slower to accelerate out of the corners so the steel cars would not keep up (timed with the same driver). (I'm sure Autodelta when developing 1300 GTA would have found this out when they used some steel GTJ 1300 shells as reported by Alfaholics 'an evolution of the 1600 GTA Corsa and enabled Autodelta to experience the 1300cc race class before the 1300 GTA was ready for 1968')

That's the whole point of building an authentic GTA replica with the same running gear and an alloy body. Your authentic GTA replica would keep up! thus you would have the same driving experience, same lap times.

If you are using a duplicate in geometry (using a standard upright instead of the GTA upright) and the authentic GTA replica has about the same lap times as a GTA, then I would keep standard upright and run the car in as many events as you can to get race hours behind the wheel. So in effect using the historical race details of GTA cars as a start point (spring rates etc) to 'dial in' your authentic GTA replica.

Steve

.
 

·
Registered
Joined
·
783 Posts
A genuine 1600GTA upright is basically a 'drop spindle' upright which places the wheel centerline at a different height and geometry to a stock upright. It is a step in correcting the subterranean front roll center when the car is lowered. The top knuckle risers are also another step in this direction.
 

·
Registered
Joined
·
58 Posts
A genuine 1600GTA upright is basically a 'drop spindle' upright which places the wheel centerline at a different height and geometry to a stock upright. It is a step in correcting the subterranean front roll center when the car is lowered. The top knuckle risers are also another step in this direction.
And my question is/was, does it actually work? (*)

Autodelta's sliding differential block came in jan 1969 (with the GTA 1300 Junior and in july with the 1750 GT Am) as an even more drastic modification to lower the roll center, be it at the back (changing the overall roll axis). So apparently, there was still room for improvement ;-)

Looking at the FIA-documentation, Autodelta's sliding block differential was never approved for the Sprint GTA, only for the GTA 1300 Junior... So if you want to drive around period correct with an sliding block diff. then the 1300 is the preferred model option to replicate.

(*): Maybe it is almost impossible to compare a stock Sprint GT with a stock Sprint GTA due to the weight difference (as Steve pointed out) but I'm interested in the roadholding (handling) differences.
 

·
Registered
Joined
·
783 Posts
Yes that re-engineered front geometry of the 1600GTA does work. For years we have been applying variations of it to normal GTVs for historic racing, and cars always increase front end cornering power. The rear end then becomes the focus for improvement, and here at least we have to run the high t'arm type set up in most classes.
Without me searching the papers, I'm sure the first version sliding block was available around '66 or '67. These had the pivot mounting face welded to the differential alloy housing, not cast in as part of the housing itself like the later version. I think they were used and tested at non-championship events before homologation for Gp2 FIA. Certainly the Mildren team cars here were running the sliding block in '66/'67 on.
 

·
Registered
Joined
·
3,134 Posts
While the original poster may have departed long ago, I am following with interest. Picked up a ‘66 GT Veloce this year. It’s complete, but would be VERY expensive to restore as original. I’m thinking fun road car in the GTA spirit, but don’t care about alloy panels. It would probably get a spare set of Beck drop spindles I already have. And they would require later ATE’s.

Were the GTA bodies really 180-200kg (396-440 lbs) lighter? That is a huge amount of weight.
 

·
Registered
Joined
·
783 Posts
Were the GTA bodies really 180-200kg (396-440 lbs) lighter? That is a huge amount of weight.
Earlier this year I wondered just that question, and having a 1600GTA and a 1600GTV in for work, plus a 1750GTV available, I set them up on the corner weight scales.
Totals were: Completely stock and original 1750 : 1040kg/2292 lbs
" " " " GTV1600 : 995kg/2193 lbs
Restored*** 1600GTA : 870kg/1919 lbs ***Non original aluminium, wheels, sump, bell & rear housing, non-drilled gear set, steel half-cage and non original slightly heavier seats, thicker springs and swaybar. I've checked original components and calculate that this particular GTA is about 45kg over at the moment, so a figure of 825kg/1818 lbs is more realistic. This car is Stradale spec. with all glass windows and chrome steel bumpers as well.
All cars had 1/2 tank of fuel and spare wheel in. '
Vince.
 
41 - 60 of 78 Posts
Top