Alfa Romeo Owners Club of Australia Forum

State Divisions => Victoria => Topic started by: t-rev on May 25, 2014, 12:04:45 PM

Title: 156 compared to spider weight
Post by: t-rev on May 25, 2014, 12:04:45 PM
Hi,i'm just wondering why a 2 litre spider is nearly 100 kilo's heavy-er than the 2 lire 156 when it actually looks smaller,is it because of extra reinforcement due to the design?And would this make the spider somewhat slower when both cars have similar horses?I find this subject quite interesting and would be happy to hear people's thoughts on the subject. Thanks Trev
Title: Re: 156 compared to spider weight
Post by: colcol on May 25, 2014, 08:36:04 PM
Cut the roof of a car and it will collapse in the centre, so you have to run extra reinforcement under the car to stop this happening, most spiders also suffer from scuttle shake as their is still some flex in the body when for example you go over a railway line or speed bump or as the local council calls them 'traffic calmers'.
The 2 door coupes are a lot more rigid and lighter than a spider, and they are shorter than a 4 door they are based on.
The Australian GTV's and Spiders are based on the older 155 Alfa Romeo that wasn't sold here, the later Spider and Brera were based on the then current 159 Alfa Romeo.
I have seen a few 'backyard' attempts at making a convertible out of a sedan, one was a original Mini that pulled up outside a country bakery, and everyone had to jump over the doors, due to the bodyflex, the doors wouldn't open!, and at a wrecker, there was an original Beetle that looked quite good but had actually broken in half, due to lack of rigidity, also i saw at the old Morwell hillclimb an original Alfasud of about 75 vintage was roofless, but with lots of steel tubes welded in where the roof used to be, and the 4 people that got in and out of it, seemed to think that it was a good thing, with not too much flex, never seen this car since, did anyone else see this car or know of its whereabouts?, Colin.
Title: Re: 156 compared to spider weight
Post by: t-rev on May 26, 2014, 05:07:02 PM
Thanks for that info Col. Are the 'twinsparks' in the gtv's and spider's tuned differently that say a 147?
Title: Re: 156 compared to spider weight
Post by: colcol on May 26, 2014, 06:20:13 PM
There are 3 different versions of the twin spark, or so i am told, early, as in 155, not sold here, then early 147 and 156 with alluminium manifolds and late 147 with plastic manifolds, the late 156's had the direct injection JTS motor.
The early Spiders and GTV's would have had the early twin spark and the late ones had the JTS, they still continued making the twin spark motor along with the JTS, the JTS was a more expensive motor to make, so it was only in the 156 and GTV and Spider, the 147 was a more price sensitive car, but some overseas 147's had the JTS motor, Colin.