Turbo systems for X1/9's

Bjorn Nilson said:
Could the restriction be in the manifold?
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I'm certainly not a turbo expert. Before beginning this project a few years ago I had no prior experience. However I've been fortunate to have direct access to several top turbo engineers, builders, and other experts at various trade events and was able to learn a lot from them. Very knowledgeable people that were kind enough to give me their contact info for further communications later. Definitely helped to understand the things I was reading in books, etc., much like attending one of those "turbo/EFI schools". Great to be able to ask questions and have a discussion to fully comprehend things.

So while I may not be able to use all the proper terminology or offer a lot of technical support, my understanding is any restriction in the system's flow (before the head, in the head, or after the head) will increase resistance and combustion temps will soar up exponentially. And efficiency drops accordingly. Furthermore if you have a knock sensor set up in your ECU then it will pull back the timing as detonation begins. But even if there is no knock control and/or charge temps don't get out of control, the restriction will have a negative effect. And that increases as flow rates increase - i.e. as RPM's go up, further compounded as the turbo gets larger and boost levels go higher. This is why you see performance turbo set-ups with huge diameter exhaust piping, very large intercoolers, big charge piping, modified heads, etc; anything to reduce flow resistance.

Therefore it would stand to reason if the exhaust manifold is 20mm smaller than the turbo, then there is restriction. Is there much room to open up ("port") the size of the manifold to match the turbo? Although the rest of the manifold may still be restrictive, as the runners are likely too small also. Hopefully one of the turbo experts we've heard from here in the past can offer a more technical explanation.
 
fiatfactory said:
and I'm afraid I totally disagree with the statement regarding relative cost/ cheaper than building a performance NA engine... it costs me absolutely nothing in dollars to port a head and gain Hp
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Possibly for you to do it yourself, given your expertise with that. But consider what you would charge me to do that for my engine. Not to mention the shipping expense. I worked up the cost for me to go both ways - performance NA SOHC, and turbo stock SOHC - and it was more expensive to make a NA engine. I'm able to do some of the work but it is the difference of getting it done right and making a real improvement in performance, vs a DIY home build that won't product the results. And from what I've learned it looks like a mild turbo system will produce much more than 105HP, plus a ton more torque. But as I said, we'll see.

Regarding the thought of putting a turbo with a carb on a Lemons racer, I think you will have definite reliability issues. Ask Bernice about the punishment that constant racing for 24 hours does to an engine. Add to that you will not be able to get a carb to feed accurate AFR's across all boost levels, RPM range, load levels, etc - not to mention inaccurate ignition timing - and it is certain to detonate when heat soak and demand go up.

The ability to digitally tune a EFI system to deliver accurate AFR's and accurately control timing is what's made it possible for the automobile manufacturers to offer production turbo engines that are reliable, dependable, and perform consistently the way they do. And this was the reason why old school carb turbo builds from years ago did not work that well. It may make power for a period, but it won't last. Read up on the tuning maps that are involved with a EFI turbo set-up to get an idea of the difference it makes.
 
Dr.Jeff said:
Ha, what century are you living in? :p There is good reason why carbs are not used for turbo systems - or just about any engine - any more. But that doesn't mean someone can't still do it, along with their breaker points ignition. :D
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In the UK we had such as the turbo/carb Maestro & Metro MG turbo with there stylish go faster body kits 🤣. Taking up Steve's point, the complexity they engineered into them was hardly worth the output.
 
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speedy fiat said:
In the UK had such exotic turbo/carb motors as the Maestro and Metro MG turbo 🤣. Taking up Steve's point, the complexity they engineered into was hardly worth the output.
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That is something like the US spec X for the California market in 1979. The state's smog/emissions requirements were much more stringent than the rest of the country. And with the ancient technology Fiat was still using - a carb system - they were struggling to even meet the national levels, let alone the Calif requirements. So they added everything in the book onto the engine to try and make it meet those limits. As you say, the complexity (or perhaps in this case 'complicatedness') of it made the car virtually undrivable.
 
I believe I've heard the stock Mk2 UT/Punto GT manifolds are much better flowing than the Mk1 was? They also allow for more turbo options (different mount type). Not sure who has which manifolds here, but is that a possible upgrade without going tubular?

That being said, I see there are some very affordable tube type turbo manifolds available for the SOHC. However I've also heard plenty of comments about the tube types cracking as @speedy fiat said. Even in cases where they attempted to add additional supports to reinforce it. Although I have to say my stock Mk1 UT manifold had lots of cracks in it, so maybe not so different in that respect. For what it's worth I was able to port the MK1 manifold considerably.
 
Dr.Jeff said:
I believe I've heard the stock Mk2 UT/Punto GT manifolds are much better flowing than the Mk1 was? They also allow for more turbo options (different mount type).
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As far as I know Mk1 and Mk2 exhaust manifolds don't differ (but plenum/intake runners do). They have both the IHI VL2 or VL3 Turbo and there's not much else that is a direct fit.
Worth to mention is that there is a support bracket bolted between the manifold and engine block as well. By removing it is a big risk that the manifold will crack so make sure sure you arrange for something similar on the 1500 engine. I don't know why PO replaced the bracket/steel plate with a tube on my engine but it works almost as good:
IMG_20200621_183336.jpg
 
Bjorn Nilson said:
Worth to mention is that there is a support bracket bolted between the manifold and engine block as well.
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I thought the Mk2 had a different turbo with a different flange pattern from the Mk1. Maybe that's the Punto GT.

I was fortunate enough to get that support bracket with the manifold. I fabbed up an extension for it to connect to the 1500 block where the EGR valve mounted - which is pretty close to where it fits in the UT block (I know, very odd place to locate the EGR). Despite the manifold having the bracket it still had cracks. Mostly at the branch to the #1 exhaust port, but also a couple around the middle of the manifold. The've been welded up and I'll just have to see how it holds up. Worst case I get the tubular one and deal with it's cracks. :D
 
Some mk2 UT had mk1 1301cc engines with IHI turbos, but normally we understand that mk2 UT had same engine as Punto GT 1,4 with Garret turbo if not mistaken

Mk1 1301 had VL2 and VL3
 
mkmini said:
Some mk2 UT had mk1 1301cc engines with IHI turbos, but normally we understand that mk2 UT had same engine as Punto GT 1,4 with Garret turbo if not mistaken

Mk1 1301 had VL2 and VL3
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You could be right. All manuals and documents I've found is unclear about many things.
 
Bjorn Nilson said:
You could be right. All manuals and documents I've found is unclear about many things.
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The Mk1 and Mk2 manifolds are very different due to the different turbo set ups. My Mk2 manifold developed some minor cracking, but I found replacement Uno ones to be none existent. However, Fiat might have sussed that there were issues, as the early Punto GT manifolds are the same and have the addition of extra ribs running along the casting, I would imagine to make them stronger. They are also easier to obtain.
7765191-exhaust-manifold-fiat-punto-gt-turbo.jpg
 
speedy fiat said:
the early Punto GT manifolds are the same and have the addition of extra ribs running along the casting
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I'm sure you are correct the ribs were to help with cracking. The one I have cracked somewhere around these areas (I'd have to go look again to remember exactly where):
7765191-exhaust-manifold-fiat-punto-gt-turbo.jpg


speedy fiat said:
They are also easier to obtain.
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Curious what the going market is for used ones in good condition?
Although I believe the later Punto GT manifolds were more improved and accept better turbos (flange wise)? Or is this the one I've heard about?
 
Since this thread has a lot of discussion about exhaust systems and the design/style of them, I thought I'd share a picture I saw online. It's a Enzo Ferrari with a custom exhaust. The question here is "how big is too big for exhaust tips"? Reminds me of those "cans" on tuner cars from the 90's.
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Ferrari-Enzo-Dragster-Cropped.jpg


I imagine this is a photoshop fake, but you never know - someone might have made such a drag car just for show; a jet powered Enzo does sound like fun.
 
Dr.Jeff said:
I'm sure you are correct the ribs were to help with cracking. The one I have cracked somewhere around these areas (I'd have to go look again to remember exactly where):
View attachment 38216


Curious what the going market is for used ones in good condition?
Although I believe the later Punto GT manifolds were more improved and accept better turbos (flange wise)? Or is this the one I've heard about?
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I paid £40 for mine. They do come up for sale second hand on a reasonably common basis as they are swapped out for tubular versions. You can still but them new, but quite pricey. Not sure about later ones
 
speedy fiat said:
I paid £40 for mine. They do come up for sale second hand on a reasonably common basis as they are swapped out for tubular versions. You can still but them new, but quite pricey. Not sure about later ones
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Thanks. That is a very reasonable price. Honestly I think I'd prefer one of these later "improved" cast iron ones to a aftermarket tubular one. Particularly considering the tendency for the tube ones to crack. But since we never had access to these cars and factory parts here, the tubular manifolds are actually more available to get here (online).

As for "later" Punto GT ones, I probibly got that mixed up with the UT Mk1 vs Mk2 styles - with a different flange for a different turbo. I don't know much about UT's and Punto GT's so it is easy for me to get things confused. After thinking more about it I vaguely recall seeing something about Punto GT being like the Mk2 UT - I think. :rolleyes:
 
Very hot weather today, about as hot at it can be in Sweden so I took the car for testing my setup. I used to have overheating problems but the aluminum radiator solved that issue. Next problem was high intake temps. I've been running a barrel type water to air IC but it didn't do a very good job above 15 deg C ambient. After watching a video on YouTube I decided to try a different "squared" type. The results are very good.
IMG_20210612_192409.jpg
Today ambient was 30 deg C. When cruising in 130 km/h intake temp was 34 deg C. While accelerating hard on 2nd, 3rd and 4th gears, intake temp climbed to 44 deg C which I think is ok. The barrel type temps easily climbed to 55 deg C and took minutes to cool down even in much lower ambient temperatures. The squared IC cooled down in seconds after a heavy turbo boost. My conclusion (just like Spyder Lee) is that the cheap Ebay squared IC is more efficient than any barrel type IC. -Even an expensive barrel from PWR. Some people mean that the cheap ones do no flow as much, but I do not notice any kind of power degradation.
If you are going for a water to air IC, I strongly recommend a cheap squared type, and not the barrel type IC regardless of price and manufacturer.
If you haven't watched Spyder Lees video I link it here:
 
Bjorn Nilson said:
Very hot weather today, about as hot at it can be in Sweden so I took the car for testing my setup. I used to have overheating problems but the aluminum radiator solved that issue. Next problem was high intake temps. I've been running a barrel type water to air IC but it didn't do a very good job above 15 deg C ambient. After watching a video on YouTube I decided to try a different "squared" type. The results are very good.
View attachment 48414Today ambient was 30 deg C. When cruising in 130 km/h intake temp was 34 deg C. While accelerating hard on 2nd, 3rd and 4th gears, intake temp climbed to 44 deg C which I think is ok. The barrel type temps easily climbed to 55 deg C and took minutes to cool down even in much lower ambient temperatures. The squared IC cooled down in seconds after a heavy turbo boost. My conclusion (just like Spyder Lee) is that the cheap Ebay squared IC is more efficient than any barrel type IC. -Even an expensive barrel from PWR. Some people mean that the cheap ones do no flow as much, but I do not notice any kind of power degradation.
If you are going for a water to air IC, I strongly recommend a cheap squared type, and not the barrel type IC regardless of price and manufacturer.
If you haven't watched Spyder Lees video I link it here:
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Excellent results Bjorn. That is a big improvement in the temps. Even the maximum of 44C charge temp isn't bad at all. ;)

So 30C is as hot as it gets there? :rolleyes::) Imagine trying to cool it in 49C ambient (or 70C air temp at the radiator). o_O
 
Dr.Jeff said:
Excellent results Bjorn. That is a big improvement in the temps. Even the maximum of 44C charge temp isn't bad at all. ;)

So 30C is as hot as it gets there? :rolleyes::) Imagine trying to cool it in 49C ambient (or 70C air temp at the radiator). o_O
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Yes 30C is about max. I am so happy, all fans; radiator, injectors, oil are doing the expected job. I would probably even handle the 49C you have (not intake though). But as someone said, it is better to put the car in garage for two months and enjoy it the rest of the year. I put my car in garage for 8 months and enjoying it for 4 months. -You are welcome to Sweden anytime😆.
 
Oil pumps.

I started a discussion about oil flow, pressure, volume, and the available oil pumps for the X engine:

Oil pumps for performance engines

The topic of "performance" oil pumps has been discussed, here's a good example: https://xwebforums.com/forum/index.php?threads/oil-pump-design-changes.37599/ The bottom line is there isn't a "performance" pump available for the X. By "performance" I mean high volume and/or high pressure...
xwebforums.com

I probibly should have posted that discussion here in this "turbo" thread because that was my intended application for a high output oil pump. Post #11 in that thread addresses why.
 
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