GTA Atmo Buyers Guide

Rust on an Alfa wasn't a shock. Par for the course

The welded up coil springs were.
I have never seen anyone do that in all my days.

It wasn't even that they had welded the pigtail back on, it was snapped in the middle.......

The Dgas is probably the simpler conversion but by its very nature, if you are after improved performance it will be limited. Firstly by the manifold design and by the air volume through the carb. Lee, there is little point in changing the cam becouse of this.
I have ported my heads and have the holly carb which is in effect two twin choke carbs one for each bank, but the inlet manifold ports are the restrictions so the max power out of the stock manifold is about 170hp becouse of air flow. I am going to make a new manifold larger even port and duel plan which should give mour torque and hopefully about 185. Btw Jo has friended you on FB.

Rust on an Alfa wasn't a shock. Par for the course

The welded up coil springs were.
I have never seen anyone do that in all my days.

It wasn't even that they had welded the pigtail back on, it was snapped in the middle.......

Well you said it! Didn't want to say what you expect with an Alfa!

The Dgas is probably the simpler conversion but by its very nature, if you are after improved performance it will be limited. Firstly by the manifold design and by the air volume through the carb. Lee, there is little point in changing the cam becouse of this.
I have ported my heads and have the holly carb which is in effect two twin choke carbs one for each bank, but the inlet manifold ports are the restrictions so the max power out of the stock manifold is about 170hp becouse of air flow. I am going to make a new manifold larger even port and duel plan which should give mour torque and hopefully about 185. Btw Jo has friended you on FB.

Interesting comments on the carb mods. What's the best solution to keep stock if you don't want the extra power and keep as original as possible.
Is the engine/gearbox able to cope with 20 or more extra BHP?

20 more BHP will be fine.

Well in the standard setup 158hp was ambitious achieved in factory conditions with no ancillaries 130/40 was the max.

Well in the standard setup 158hp was ambitious achieved in factory conditions with no ancillaries 130/40 was the max.

So you're saying that in standard road trim it topped out at 140 at best? Bit cheaky to quote 160. My Grand Scenic quotes that but probably won't do 0-60 in 6.5...........Oh I don't know though!! Or was that a misnomer too?

I am no longer a flat out speed man as there are to many cars on the road now, but I do love cornering and the Atmo is amazing because of its instantaneous smooth power delivery and balance. I also have a 610 it is an amazing car comfortable and very good for long journeys but when you're in the corners on the road and you start wanting to put power on and off it is very frustrating, as you put your foot down where is it and then it comes in.
All I am trying to do with my Atmo is to increased the output to a level where it matches the grip of the car when cornering hard with your foot hard down which I recon is about 180hp on standard rubber.

Personally...I'm not so sure they were short leaving the factory...30 years on if not maintained then yes.
Speaking personally...the atmo on a twisty track and short straights is a match for a (stock) turbo.
The reality is that atmos are not a regular feature on rolling roads...so there is not much data out there.
(As sessions are expensive relative to car value...and the tuning potential limited to I guess ...25%...whereas a turbo starts at this level and can go up another 30-50% ).
Stock carbs are fine if they work well..but it might take £600 to get a rebuild and professional set up...and it might still not be 100%... that's why the Holley kit from JL Engineering or similar is popular for ~1000 and a DIY install.
I have stock carbs (rebuilt 12 years ago by Paul Sage and a sports exhaust)..and it's served me well..feels quick enough.(although it's running rough in the last month ..but not carb related.)



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[Alpineandy]

Well in the standard setup 158hp was ambitious achieved in factory conditions with no ancillaries 130/40 was the max.

I think you may be getting a bit confused between the 2.68 Litre A310 V6 (150bhp) and the 2.85 litre GTA (160bhp).

thats pretty much the same, for an old car that is not likely to be making original power levels any more.

[stephendell]

Speaking personally...the atmo on a twisty track and short straights is a match for a (stock) turbo.

Quicker actually in the early factory testing

that was just in "testing".
Hopefully we will see some Atmo cars sprinting and hill climbing soon ???

When my one is finished it may be going up the hill.

Glad to see this topic has started some lively debate and discussion! Very informative. Shame I haven't got one to contribute........yet!

Any other pearls of wisdom?
Les