Great info againAs regards availability, I'll repost some websites in the U.S. that I provided recently that are major stockists of124 Spider parts - some of these stock pistons of various compression ratios (cast or forged), some can even supply rebuilt engines, cyl. heads, and manual transmissions:-
There are also 124 Spider parts suppliers in the U.K. (an internet search will find most of these), but here's a couple in Europe that are worth perusing:-
As regards different cams, I've seen mention that the cams fitted to the 124 Sport 1438cc engine were better that those fitted to the larger capacity engines, but there's not much difference in valve timing figures and minimal if any difference in lift - I don't have any info on the Lancia cams, which is a little funny as I worked for a Fiat+ Lancia dealer and worked on lots of Beta's (Saloons, Coupes, Spiders, HPE's) and remember them fondly - terrible pity that they withdrew from the U.K/Ireland and didn't stand firm against their critics, could have pointed out that other makes of cars rusted just as badly, if not worse. Oh, well.
I did play around with some Piper cams with reasonably good results, Also tried having just the base circles ground down on standard cams to increase lift (i.e. leaving the valve timing more or less unchanged) without much noticeable improvement but a bit of a palaver setting them up to work - had to even machine the cam-boxes to set the valve clearances, sufficiently thick shims not being available, might have overdone the grinding of the base circle.. Did a bit of reading on cam design/valve timing/ acceleration/deceleration rates of valves and the problems that can arise. It's a massive and complicated subject and imho modifying cams is probably best left to 'the experts'. Also read the famous book - The Scientific Design of Intake and Exhaust Systems - made me feel very ignorant!
You seem to have gotten your dual twin-choke carb set-up to work ideally, so well done to you and your 'rolling-road' specialist, unfortunately, many others have been disappointed, probably due to incorrect set-up/jetting, inability to adjust/balance the carbs themselves or find someone capable of doing so, which is why I urge caution to those thinking of spending quite a bit of cash on such a conversation to be aware of the possible downsides.
I was going to purchase Guy Croft's excellent book shortly after it came out, but having read a friend's copy, I decided it was too much race/competition modifications oriented for my needs at the time so didn't buy. Given how much these books are now being advertised for sale at, I wish I had bought one when it was c. Euro 38 (iirc, books are dearer here in Ireland than in the U.K.), saw a couple of ad's from the U.S. on eBay? recently @ $500 - 600!!
I fully agree with your advice about not overdoing things on a car, just set it up to suit your intended usage and include the little modifications that make it a nice place to be - I believe classic car ownership and driving, should be a pleasure not an uncomfortable ordeal.
Interesting that you mention 'polybushes', there was a feature/write-up in Practical Classics magazine in the U.K. (April 2025 issue) about a guy that restored a Fiat 124 Spider from the 'States (this car also had a broken oil pump and a dented sump, sound familiar to you?), he had fitted 'polybushes' and now intended to revert back to standard bushes... In the same magazine issue, the editor has now gotten 2 x 124 Spiders and intends to make one good car out of 2, there's quite an amount of body repairs needed, it'll be interesting to see how things progress in future issues. I'd scan and upload the relevant pages from the magazine but I don't want to possibly contravene copyright rules or upset anyone at the magazine. But issues of this magazine can be viewed digitally/online, (will require a digital subscription c. $62/year for U.S. ,13 issues) if anyone is interested. To order a digital subscription :-
Practical Classics Magazine
Practical Classics is an original classic car magazine that has been providing help and inspirations for car enthusiasts since 1980. Become a subscriber today!www.greatmagazines.co.uk
Ref Cams……
In my youth I experimented with reground cams in my Beta Coupe. I went for race profile as the regrind was the same price!
Unless you buy new cams with the correct base circle and you want a track car dont waste your time and money
Regrinding the base circle to increase lift means you need to machine down the cam boxes to keep within the range of standard shims
I decided to make my own shims! I measured the hardness using a Brinell tester then selected silver steel which could be hardened post machining
The resulting shims were very thick and heavy! The accelleration forces in the valve train are immense. Heavier shims resulted in massively increased cam wear! The lobes went asymetric within a few hundred miles! Initially the car was virtually undriveable with no power below 3500rpm! Then it went like a scalded cat!
I like the approach advocated by Guy Croft, he spent ages evaluating stock parts and interchanging them between different engines.
In the extract below fitting stock 1608 cams. In a 2lit engine can result in 8hp increase.( no machining, stock shims)
The downside is the time taken to find the parts as they become more rare. Buying a spare engine for £500 is a great idea if you see one, but check the spec carefully (block & head casting numbers) Lancia TC’s generally perform better like for like than Fiat TC’s but the engine is inclined so you cant use sump and cam boxes
