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Discussion Starter #1
Hi there,

Does anyone know if the Autodelta GTA engines/blocks were numbered back in the period?
Reason asking, is that I have in my pocession a (damaged) period correct block with a number starting AD ...
I was going to make a coffee table out of it......:)

Best regards,
Per
 

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I have a GTA block unnumbered, A customer had an unnumbered GTA Junior block. Neither had/has AD prefix, both just blank number pads. Below is my GTA block. The "thing" under the pad is a blue aluminum gallery plug as this block is now drilled as a 5 oiler. The Jr block looked the same.
As I restore quite a few GTA and Jr oil pumps, the series 1 GTA pump upper bodies all only had a "A" stamped on them, as shown. These upper bodies gauged minimum machine tolerances as compared to others. Some were used on non-race street pumps, but not many. Very few ever had the same A on the pump bottom.
 

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Discussion Starter #4
Spiderserie4, yes.
It looks pretty original to me.
The number in a 3 digit number and one could imagine it does correspond to the last 3 digits of a car's chassis number 613xxx.
The xxx in question is not registered in Allegerita which would very well match the car it came from (which I sold years ago)
Per
 

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Hi, certainly not production GTA blocks, but SOME previously un-numbered special purpose blocks were numbered with an AD prefix.
I think this would have been done when Autodelta provided a new special order engine. Over the years I have seen 16valve, GTAm 8v and I think one of the 1900 GTA engines I've rebuilt with such markings. Although, having said that, most of the special purpose blocks I've been in contact with have been blank like Gordon's.
I've also seen the sliding block differential housing with AD on it, & I know this came from a '65 Autodelta race car.
regards,
Vince.
 

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Very likely an Autodelta special of some sort. Anyone else have any GTA race parts with AD markings we can get photos of for this thread?
 

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I have seen a block, most likely a monosleeve block, stamped AD #. I cannot remember how many digits but think it was 1 or 2. The mono sleeve block that I had was a 1750 prefixes 00548.

The yolk that the block slides in on the sliding block rear suspension has Autodelta cast in both sides.

Ciao

Ken
 

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engine blocks Autodelta

All engines prepared by Autodelta using new unstamped blocks had the prefix AD.....for example 45 .
If they used a custumer block , the block had the number of the GTA *005.59 * 125669*

The A on the oilpumps has nothing to do with Autodelta, is common on varios pumps i saw.
 

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Thanks! This is a help to me. I've always wondered.
The series 1 GTA oil pumps we received from Autodelta at AUSCA were all marked with the "A". Those were the early ones with the main-shafts that did not break. Rockwell testing showed different hardening was used on early and late GTA pump main shafts.
 
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i am astonished, we never had broken oilpumpshafts???? This is more due vibrations than harding fault , i would say ? But will learn about.
 

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Block looks fixable to me ...
Pete
 
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If you have never broken a series 2 GTA main shaft, or had an original magnesium front cover crack at the distributor mount base / front cover interface, count yourself LUCKY. It ruins your race day. Most of these incidents happened in the Trans Am series here in the USA, but it was not limited to only Ausca prepared GTA's. The earliest shafts would absorb more abuse and twist than the less springy later shafts. When those broke, we made "shaft-links" out of them, if enough was left, allowing us to use a race prepared (double steel helical geared) 1600 Veloce pump with the broken off and now modified series 2 shaft top to drive the GTA distributor. See pictures below.
The cracked or sometimes shattered magnesium front covers were replaced with aluminum front covers also as seen below. We also broke quite a few of the early magnesium bellhousings, the second Autodelta version was better, the third Autodelta Mg housing the best. Early on as replacements, we used 1300 Alfa truck bellhousings made for column shift trucks in Europe, as they were physically heavier and thicker castings than the passenger car versions. I sold my last old column shift truck housing to a racer last year.
Most race-stress-testing was with the earliest cars, and both Alfa and Autodelta provided upgraded components over time.
Today I still build quite a few GTA oil pumps for racers and most have better components than we had in '65 with better metallurgy and more precise machining and hardening techniques.
 

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Fascinating history here for us youngtimers (51), thanks !
 

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Yes , the early frontcovers from magnesium were a problem, nevertheless we spoke over distributoeshafts!
The much more problem was the corosion of the early frontcases from magnesium , they are all changed on waranty by Alfa Romeo Frankfurt 1965 till 1968 .....water found the way to oilarea in engine....
And the cracked bellhousing are common problems on all Alfas till 2000 series . We used the aluminium part from Sprint GT or TI ....
The original GTA startermount are integrated silentblocks , often forgotten to reinstall after starter change....the result was also cracked magbells...
I am not sure , if the frontwheeldrive bellhousing from lorry fits? never used, why , the bell from GT was strong enough.

By the way , i never saw a coloured inside of an GTA engine , does this has any reason or its only for the optic ?
 

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Hi Gordon,
Interesting with the short little oil pump/distributor shaft. I came to basically the same arrangement back in the '70s when adapting a GTA head & distributor only to a 2000 bottom end.
Also about the 1300 truck bellhousing; what model was that? OR perhaps they were form column shift 101/105 Giulia?
The reason I wonder is that the Romeo vans & trucks had a ZF transaxle & the bellhousing is nothing at all like needed to attach to a Giulia type 'box.
regards,
Vince.
 

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They were OLD Vince, No idea how Ausca sourced them. Mechanical F & S clutch type. Hole for flywheel timing marks. 1300 101? Some had column shift parts hanging on them.
 
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