Disadvanteges of a higher cam in an uno turbo

There are a couple of Piper cams for UT on the market that seems interesting, and if any member has any experience from them I would love to hear from you. I am especially interested in the "rally cam" that eventually would give me more revs and a wider powerband.
-Sorry for hijacking the thread😏
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When I was looking at cam options for my 1500 X1/9 engine turbo project I considered the UT cam. The thought was it is a turbo spec cam for a very similar engine so it might be an improvement over the X's 1500 (US spec) cam with a boosted application. And obviously no one makes a turbo spec cam for the 1500 X engine. I was very surprised at the very low specs for the stock UT cam. Frankly it is rather lazy and not any real improvement over the US spec NA 1500 cam. In fact I read where some UT guys have installed the X's stock cam for an improvement. So I looked at what's available from the aftermarket cam makers for performance cams for the UT. Again, I was rather surprised at the specs. Several of them had a lot of overlap, which as I've said is considered the worst thing you can do on a boosted engine. And some were extremely radical in terms of the RPM range, obviously intended only for race application. The only advantage I saw with any of them was the increased lift - and some had a LOT of lift. Possibly too much depending on what valve springs you run, what valve to piston clearance you have, etc. But again, on most of them the biggest problem was the overlap; as lift got higher so did duration and overlap. And the prices were significant, particularly when shipping to the US and the exchange rate were considered. The bottom line is the best option I found was the stock Euro spec 1500 X1/9 cam. Almost no overlap, good lift, plenty of torque in the lower to mid range, great idle, and smooth acceleration to redline. I think that might be one of the best choices for a UT engine that is intended for road use (race track use only is a different story). Particularly a relatively stock one with the original ECU.
 
I presume that the extra air by the 1 bar boost is measured by the afm? Which tells the ecu to inject more fuel.
 
And obviously no one makes a turbo spec cam for the 1500 X engine.
Yes, the stock UT cam is lazy and it doesn't rev much more than 6k. -Boring! An X1/9 EU cam is probably a better choice, but I don't have one. My cam is from a Regata engine and it provides a lot of torque but is completely dead above 7k as I said, and I would like more top end from it, especially on the race track. I am almost sure an X cam would provide more top-end power than the Strada cam, but less midrange torque.
As you say, the bad side with high lift is that overlap is hard to avoid. But Cat Cam manufactures a cam for turbo converted 1500 X engines. Unfortunately Cat Cam do not offer modification of existing cams so they are more than twice as expensive as Piper, so again the X cam is probably the best choice (if you are lucky to have one). A rebuilt Piper cam costs 167 GBP.
I wonder what kind of cam the Italians have in their crazy 400hp Unos on Youtube. They are revving like 9-10k.
 
But Cat Cam manufactures a cam for turbo converted 1500 X engines.
I'm surprised. Is that something new? I did not find any cams for a boosted X SOHC when I looked, but that was a couple years ago. I'd like to see the specs for it out of curiosity, but I'm with you - I'm not going to pay the price to get one.

Henk in the Netherlands has some new Euro spec 1500 cams listed. A bit expensive but they have become very hard to find:


I wonder what kind of cam the Italians have in their crazy 400hp Unos on Youtube. They are revving like 9-10k.
Most likely one of the wildier race cams from someone like Cat or Piper. Makes a big HP number, but I doubt they are very drivable.
 
And what do they refer to? Uno Turbo? Fiat 128?
The specific link goes to the "Fiat 1.3-1.4 Turbo 128 (engine)". But I also looked in the "Fiat 1.0-1.6 SOHC 8-valve 128 (engine)" section and found only high performance ones.

It appears the reference to "new" cams is opposed to "reground" cams, which they also offer, both in "performance" grinds. But not to "new stock spec" cams.
 
I've also read that a Mk2UT 1.4L cam is a decent upgrade - but I'm going to run a stock Mk1 cam with the boost turned up :)
 
I've also read that a Mk2UT 1.4L cam is a decent upgrade - but I'm going to run a stock Mk1 cam with the boost turned up :)
When I looked into the Uno cams as a possible choice for my 1500 turbo build, I compared the stock ones from the Mk1 and Mk2 UT and the Punto GT Turbo. There really wasn't much difference between any of them. A little, but I don't think enough to make a lot of difference in performance. Honestly I would not waste my money and time switching between them if I already have any one of them.
 
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