Turbo systems for X1/9's

Yes, thanks for all input it has been very useful. This is a world class forum.
I had difficulties finding EV1 injectors in range of 350-400cc so yesterday I ordered 440cc MSP injectors that will work with my hose mod and top adapters. Lots of people in UK are running their UT's with even bigger injectors w/o problems, and I think the super fast MaxxECU wll handle it just like you say Speedy Fiat. I also ordered individual Bosch ignition coils and a 4 channel (sequential) trigger so I am slowly getting there. Fueling done, ignition done, sensors done. Turbo and IC next... And I almost forgot, clutch. -Seems to be tricky with a X1/9 gearbox on an UT flywheel. OR, I'll eventually go for the X1/9 flywheel but finding a clutch capable of 200-250hp and lot of torque is not easy.

The only clutch I found that could handle the extra power and torque was a Helix ( http://www.helixautosport.com ) competition plate and cover for a 1.3 Uno Turbo. From memory they say they are good for at least 200hp and so far it's been faultless, albeit a little harsh on take up. I agree with Jeff in thinking you only need the Uno 1300 flywheel if you are using it to trigger the ignition. The 1400 Uno flywheel won't fit without a lot of grinding of the bell housing. I was advised against going too mad with lightening the flywheel as apart from the obvious safety concerns it was suggested that the benefits to be gained are no so great with turbo engines.
 
I am in contact with Helix and they are very helpful. They did not recommend the rally/race clutch for street use as it is very aggressive. But the Fast Road clutch also handles +200hp and lots of torque. However, It seems to be a problem finding a clutch if not keeping the UT flywheel. But keeping the flywheel would eventually create another problem with the starter from X. I will not use the UT flywheel for triggering as there will be a 60-2 trigger wheel on the crank, so if possible I go for the flywheel from X. And here starts the problem: A strong clutch is not available for all 1.3 and 1.5l X engines and Helix refer to engine codes that even not exist, and I suspect my engine comes from a Fiat Regatta 85S (138 B3 046) which makes it even more complicated. -All 1.5l do not have the flywheel in common it seems.
I will remove the engine from the car later this week, tear it apart and measure the clutch. I hope that will help Helix to make something that works out for me.
Having a X sometimes requires detective skills ️‍♂️
 
Bjorn, are you saying the flywheel that you will be using is not a X1/9 flywheel, but a Regatta one? We did not get Regattas here so I do not know anything about them. Is the flywheel the exact same as a X unit? Are the starters the same?
 
I am not 100% sure Jeff. In my world European 1.5l X1/9, Strada, Ritmo and Regatta share the same engine and gearbox with very small differences. Strada is just a renamed Ritmo and Regatta is basically a Ritmo Coupé. Based on the engine code, my engine comes from a Regatta. I will measure and have a picture of my (Regatta?) flywheel and hopefully someone on the forum can help to verify it is the same as X1/9. I've heard that the UT flywheel is slightly smaller than the one from X, and the X starter might slip and damage the flywheel teeth over time. I will measure and verify that as well.
https://www.wikiwand.com/en/Fiat_128_SOHC_engine is a good page for comparing engines in the family but unfortunately not other things.
 
I've also heard the X1/9 starter will not work with the UT flywheel. Check with "mkmini" on this, he went through it with a few different Fiat engines and trans for his X1/9 - UT project. Also keep in mind the 1300 and 1500 X1/9 flywheels and clutches are different, so there may be more to look at in terms of upgraded parts with that change.
 
According to my Regata Haynes manual the clutch is 200mm diameter. The X1/9 is 190mm same as the Mk1 Uno turbo.

From the Ultimate SOHC guide,

" Flywheels.

Uno Turbo -122 tooth count
1300 X1/9 (4 speed) -120 tooth count
1500 X1/9 (5 speed)-124 tooth count"


Therefore the starter needs to be matched to the flywheel.

BTW the Regata is basically a Strada/Ritmo with a boot not a hatchback.

Andy
 
I'm not at all sure about this, but I sort of recall something about the clutches also being different aside from their diameters? Therefore they are not interchangeable even if the flywheels are the same diameter? But I really do not know any details.
 
Its the spline count on the clutch/input shaft of the gearbox.
One is 17 the other is 20 but off the top of my head I can't remember which way round it is.
 
That makes since. Could there also be any differences in the overall thickness/offset of the pressure plate (relative to the engine, transmission, clutch arm movement, etc)?
 
Strada/x1/9/ bottom change Uno turbo 17 teeth.
late Mk1 and Mk2 uno turbo 20 teeth.
200mm Regata ?
 
I am not certain but I recall something about the UT flywheel is not a direct fit with the X's gearbox?

Actually, I think it fits just fine - but the X1/9 starter motor won't engage the teeth. You would need the UT starter. If you scroll down this post, you'll see FastX19's response (Eric Armstrong). I can't remember where I put my UT starter motor! I currently have a reduction gear starter motor, so I'll see if I can change the gear to match the UT flywheel.

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https://xwebforums.com/forum/index.php?threads/uno-turbo-cams-1-3-vs-1-4-in-a-mk1.22700/#post-185769
 
My thinking about the clutch pressure plate differences, verses the friction disk differences (number of splines), is if the pressure plates are interchangable (with the same diameter) then you can use a higher pressure rated one from any model that is available, with the friction disk that fits your transmission shaft (splines) and diameter. That may allow for more options in finding something that will fit and have greater performance. The friction disk can always be reworked to have a better material added if it does not offer enough bite.
 
I was there abot Year and a half ago, so everything I can remember is not worth to post. At the moment I have flywheel from X19 I suppose, because all UT management system I sold including flywheel. UT flywheel was different, not in diameter but it had 2 more teeths IIRC, at the moment I have X19 flywheel with Punto starter motor, does it work that way I don’t know yet. To be sure about difference in starters and flywheels You should scroll throgh my thread ~ 1981 X1/9 Uno Turbo , if I had mentioned it there
 
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few pictures of my thread.
That means that I used UT flywheel with X19 starter motor, for few days when it was in running condition :D I don’t remember that I drilled starter to pit screw through.

*but I sold UT starter with flywheel and managememt system, oooh my input here is too much questionable, sorry
 
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I have two gearboxes. One was included in the UT deal, and the seller told me it is a X1/9 box. On that one the shaft messures 18.3mm and has 17 splines. The bearing inner diameter is 28mm.
The other one is still in the car and is most likely also a X1/9 box. I will measure it in a couple of days once it's out of the car. I will try to use the tranny that came with the UT engine. It seems to be in a good condition. Helix can manufacture a clutch for this box and an UT flywheel. The gearbox currently in the car is leaking (a lot) and need overhauling.
 
That means that I used UT flywheel with X19 starter motor, for few days when it was in running condition :D I don’t remember that I drilled starter to pit screw through.

*but I sold UT starter with flywheel and managememt system, oooh my input here is too much questionable, sorry
Seems like a Catch 22...
To be safe I will use the flywheel and starter currently in car (X1/9 or Regatta). The UT flywheel would just cause problems, and I do not need it for triggering purpose.
Hopefully I'll find a clutch that's strong enough. I'll send Helix my measurements and hope for the best.
 
To be safe I will use the flywheel and starter currently in car (X1/9 or Regatta).
Sounds best.

Hopefully I'll find a clutch that's strong enough. I'll send Helix my measurements and hope for the best.
If it is a known flywheel and clutch (e.g. for X1/9 or Regatta) then I imagine Helix will know the dimensions and already have something available for it (or can easily make it). I think they could design it to your specific needs; pressure plate force, friction disk material, etc. That should be a good solution.
 
Regarding the recent conversations on injector sizes. This fuel injector service company's website (link below) has a couple of calculators that you can play with. The variables include things like fuel system pressure, ECU duty cycle settings, turbo vs NA, fuel type, etc. There are two calculators; one to input your engine/fuel system parameters and calculate the suggested injector size, the other to input an existing injector size and see what it can support. These calculators are generic and do not account for specific engine design variables (efficiency, etc). But there is also another calculator that is vehicle specific. Naturally it does not include older vehicles and certainly no Fiats. But you might play with it as well to see how things change between various vehicles (engine designs).

Link: http://fuelinjectorclinic.com/index.php?route=product/category&path=258_456
One of the calculators: http://fuelinjectorclinic.com/flow-calculator

A little look seems to confirm pretty much what I previously understood - at least for my requirements. That is, for a mild turbo on a basically stock X engine, the BMW injectors I referred to earlier have more than sufficient flow rate (roughly 280cc). The fact these injectors fit the stock fuel rail and integrate easily with the rest of the system, not to mention were extremely affordable, made them the perfect choice for my project.
 
Regarding the recent conversations on injector sizes. This fuel injector service company's website (link below) has a couple of calculators that you can play with.
One of the calculators: http://fuelinjectorclinic.com/flow-calculator

A little look seems to confirm pretty much what I previously understood - at least for my requirements. That is, for a mild turbo on a basically stock X engine, the BMW injectors I referred to earlier have more than sufficient flow rate (roughly 280cc). The fact these injectors fit the stock fuel rail and integrate easily with the rest of the system, not to mention were extremely affordable, made them the perfect choice for my project.
I used the same calculator on BJP Race web site, it seems to be a common method for calculating injector size. The only difference is that BJP recommend a Duty Cycle of 80%.
The BMW injectors seems to be a good choice of not going wild in hp like me. For my application I need at least 417cc injectors, and 440cc MSP EV1 STANDARD injectors is the closest I can get. As they are shorter than ex Volvo injectors I had to revise my previous "hose mod":
I changed the injector bore to 12,5mm to allow the injector go further in to the injector tube to compensate for the shorter length. I used a combined O-ring/hose made for Japanese cars/injectors and enlarged inner diameter to 11.5-12mm (the one to the left in pic.) for tight fitting injector - larger injector bore. -No longer need for the original lower O-ring (right in pic.). I used a Hose Adapter to connect the injector to the fuelrail.
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