Alfa Romeo Giulia TI, Giulia Super & 105 Berlina Boot Spring [403.17200]

Alfa Romeo Giulia TI; Super; 1750 & 2000 Berlina Boot Spring      P/N 403.17200    Sold as a SINGLE SPRING – discount for 2 purchased together [see order quantity panel]

Spring for the boot [trunk] lid on all 105 Berlina cars

Giulia TI; Giulia Super; 1750 Berlina; 2000 Berlina

Replacing the original 105 14 56 172 00 Alfa Romeo Springs.

These springs have been produced after a long period of investigation into the requirements to ensure they perform exactly as Alfa Romeo intended originally.

“The lid would pop from the initial locked down position and then will raise with minimal effort by hand, and can be stopped, and will remain, at any position from closed to full open as required”.

Unfortunately as most owners are well aware, this situation only lasted for maybe a couple years of operation [if you were lucky] before a prop was required to hold the lid up or extra springs were jury-rigged alongside the originals in an effort to stop the lid coming down on an unsuspecting person’s head.  

Our springs can be fitted to any of the 3 positions provided on the support brackets to enhance the lift if so required by the owner, however it should only be necessary to use the first position.

Springs are priced SINGLY. However we recommend the springs be purchased and fitted as a pair. [Discount applies, see order quantity panel above]

Our springs have been computer designed to travel through the functional arc of the hinge without ever reaching the critical stretch position that causes any spring to take and hold a “Set” which is the problem with the design of the original springs fitted to these Alfa Romeo sedans.

As hardly any thought is given to these springs other than to condemn them as useless, no-one has taken the time to ascertain the actual reason for the problem.

Virtually no-one realises that the reason for them failing is that they are in a state of almost full tension ALL THE TIME THE LID IS CLOSED.

They are only ever, almost – but never quite, in a relaxed state when the lid is fully raised. Consequently, if the spring is at, or very nearly at, its critical stretch or extension position for virtually all the time, this is why they fail. 

The original Alfa Romeo springs were actually far too short for the job function. There is a comparison photo here of original Alfa Romeo springs and the new springs we have designed and made.
The difference is significant.

Original Alfa Romeo springs, our new springs 

TOOL REQUIREMENT FOR REMOVAL & REPLACEMENT OF SPRINGS.
Very simple tool is all that is needed. Don’t try using long nose pliers or screwdrivers.
1] A piece of strong [laminated 13 ply 11/16” marine timber is strongest for size] [see photos] 2’6” long x 1-1/8" to 1-1/4” Wide.
2] A 9" length of 1/16" mild steel welding wire, minimum diameter, no thinner.
3] Our small shaped aluminium block.   alloy block here

Pass the wire through the hole in the block, twitch around the wood and twist ends together a number of times, leaving a space between the block and the wood, with the hole in the block 3/4” from the edge of the wood [photo on additional images page]  

The alloy block should be positioned about 6” from one end of the wood. There is a blind hole in one face of the alloy block, the end of the spring hooks into this hole [photo]. The short end of the wood is held against the end of the rib on the inner guard and the long end pulled down against the spring and then away from the bracket. Does not need to come down very far, then slowly release pressure and allow spring to contract. Remove tool and lift upper hook of spring away from the mounting hole.

Fitting new spring is reversal of operation. Place upper hook in mounting hole in body, position lower hook in alloy block [photo], hold short end of wood against rib-end and while pressing spring against the bracket, pull down on long end of wood. Move lower hook of spring back towards the bracket. slowly raise the wood allowing the hook to engage with the bracket.
The sequence of photos should explain this process.    

Our springs have been designed and manufactured right here in Queensland from Australian spring steel. We commisioned a renowned spring specialist to study the problem and he worked through all the computations to compensate for the causes.

For those interested, the following are the calculations required to determine the requirments of extension springs

CALCULATIONS

Close coiled spring

R = Mean radius of the spring

N = No. of Coils.

d = diameter of the wire.

N = Shear modulus of the spring materials.

W = Load applied.

= Deflection

Spring Test Standards used to develop our springs

Springs have individual design specifications, derived from materials used, manufacturing method, and finish. These characteristics each have their own industry standard specifications in turn. But the only way to ensure performance to specification is to test in line with standard test methods for springs. Using British Standard 1726-2: Guide to methods of specifying, tolerances and testing, Extension springs and Cylindrical helical springs made from round wire and bar.

Video showing ease of removal of spring using this method.

»  https://www.flickr.com/x/t/0093009/photos/52357060@N08/36746628366/

With a pair of our new springs fitted the boot lid will now remain in any position from closed to fully open