Stilo1.8 16v swap

[My1stCar]

Sorted the coolant reservoir with a new mount at the bottom and some struts I made from left over 10mm tube (that I used to extend the shifter cables):

I use the original stainless reservoir of the 1300 engine, as it's much nicer en bigger than the plastic one of the Stilo. Bigger to better deal with the coolant expansion when it gets warm (I need to find a new cap though, or paint this one).

I had to flip the reservoir as the main connection at the bottom/front was interfering with the engine mount. Now it is at the bottom/rear.

It also had to be raised too, so that 3/4 full is about the max. level of the original reservoir.

The lid closes without touching anything (the EPPM intake tube was easy to nudge down with some heat).

 

[My1stCar]

Working steadily on finalizing the engine bay before painting it the same color as the car.

I repurposed part of the admission of the Stilo, paired to a K&N pod filter.

And fabricated a shrould that boxes the pod filter in the left air duct.

But having seen the super tidy K20 fitment by @Matt Brannon - Midwest Bayless in today's post of @JimD 's car https://xwebforums.com/forum/index.php?attachments/20221205_142632-jpg.68617/
I wondered if the shroud is a good idea?

It does make sure the engine breaths cold air, but the trade-off is that the size of the filter is limited due the space left in the "air filter box". A bigger filter could be fitted otherwise, but that would aspirate also warmer air from the engine bay.

Any opinions?

 

[dllubin]

I hooked up my 1300 air cleaner with a 4" hose to the driver side scoop. Opening the air cleaner intake to 4" made a difference but connecting it to the air scoop did not help.

 

[Jonohhh]

Working steadily on finalizing the engine bay before painting it the same color as the car.

I repurposed part of the admission of the Stilo, paired to a K&N pod filter.
View attachment 68648
And fabricated a shrould that boxes the pod filter in the left air duct.
View attachment 68649
But having seen the super tidy K20 fitment by @Matt Brannon - Midwest Bayless in today's post of @JimD 's car https://xwebforums.com/forum/index.php?attachments/20221205_142632-jpg.68617/
I wondered if the shroud is a good idea?

It does make sure the engine breaths cold air, but the trade-off is that the size of the filter is limited due the space left in the "air filter box". A bigger filter could be fitted otherwise, but that would aspirate also warmer air from the engine bay.

Any opinions?

That air filter size *should* be adequate, however if you aren't convinced, perhaps you could get a similarly dimensioned one with additional filter media on the end, as some K&Ns have?

As far as the side vent for the intake, I really like that idea and have the intention of doing the same to my car, once it gets to that point. The intake area should be adequate for that engine, however, if I remember correctly, there's a complex and restrictive-looking "grate" of sorts. It does not appear that it'd be particularly effective in filtering out water droplets, only larger debris, and could probably be easily replaced by a less restrictive mesh. Drag properties of some common mesh materials can be found online, if you go that route.


Additionally, I'm very excited to see how it sounds with the engines induction noise all piped through the left hand side vent. It should sound absolutely fantastic , perhaps removing the Helmholtz resonator on the intake tube could give a nice boost in volume as well, if it ends up sounding strangely muffled at certain rev ranges.

 

[Dr.Jeff]

That air filter size *should* be adequate, however if you aren't convinced, perhaps you could get a similarly dimensioned one with additional filter media on the end, as some K&Ns have?

As far as the side vent for the intake, I really like that idea and have the intention of doing the same to my car, once it gets to that point. The intake area should be adequate for that engine, however, if I remember correctly, there's a complex and restrictive-looking "grate" of sorts. It does not appear that it'd be particularly effective in filtering out water droplets, only larger debris, and could probably be easily replaced by a less restrictive mesh. Drag properties of some common mesh materials can be found online, if you go that route.


Additionally, I'm very excited to see how it sounds with the engines induction noise all piped through the left hand side vent. It should sound absolutely fantastic , perhaps removing the Helmholtz resonator on the intake tube could give a nice boost in volume as well, if it ends up sounding strangely muffled at certain rev ranges.

I agree with @Jonohhh. You can get a filter that isn't tapered and includes additional filter material on the end to replace the one you have. That will add a reasonable amount surface area without necessarily getting larger overall, so it will still fit in your box. Maybe one that is slightly longer or slightly greater diameter will still fit in the box as well? A little more surface area can definitely help if the current one is a borderline size.

The stock side vents are actually quite restrictive. The design is a bit complex; a grate on the front side of the scoop, more grates/grills on the back side, a transitional piece between the scoop and the body, a foam block, all going through a rather small hole in the inner body structure. If you want to improve the airflow then you can cut out those grates/bars, modify the transition to the bodywork, and smooth out the whole shape. Here are what some of the plastic bars/grates look like:

Or if you REALLY want an improvement you can do this:

 

[My1stCar]

I agree with @Jonohhh. You can get a filter that isn't tapered and includes additional filter material on the end to replace the one you have. That will add a reasonable amount surface area without necessarily getting larger overall, so it will still fit in your box. Maybe one that is slightly longer or slightly greater diameter will still fit in the box as well? A little more surface area can definitely help if the current one is a borderline size.

The stock side vents are actually quite restrictive. The design is a bit complex; a grate on the front side of the scoop, more grates/grills on the back side, a transitional piece between the scoop and the body, a foam block, all going through a rather small hole in the inner body structure. If you want to improve the airflow then you can cut out those grates/bars, modify the transition to the bodywork, and smooth out the whole shape. Here are what some of the plastic bars/grates look like:

View attachment 68668View attachment 68669

Or if you REALLY want an improvement you can do this:

View attachment 68671View attachment 68672View attachment 68673

That is sleek and increases airflow for sure. From the looks of it it's preserving the structure and even adds torsional stiffness by boxing in the top.

For the moment I'm going for the as close as possible to stock external looks, but will definitely open the side vent as you and @Jonohhh suggest

 

[Dr.Jeff]

adds torsional stiffness by boxing in the top.

Actually I boxed all sides of the enlarged openings so hopefully it is at least as strong/stiff as it was originally.
Not shown are the custom air scoops that will be attached to the outsides of those openings...the new scoops are also MUCH larger than the stock ones. But all of this is definitely a non-stock looking mod, which my car is full of.

 

[kmead]

Sorted the coolant reservoir with a new mount at the bottom and some struts I made from left over 10mm tube (that I used to extend the shifter cables):
View attachment 68155
I use the original stainless reservoir of the 1300 engine, as it's much nicer en bigger than the plastic one of the Stilo. Bigger to better deal with the coolant expansion when it gets warm (I need to find a new cap though, or paint this one).

I had to flip the reservoir as the main connection at the bottom/front was interfering with the engine mount. Now it is at the bottom/rear.

It also had to be raised too, so that 3/4 full is about the max. level of the original reservoir.
View attachment 68156
The lid closes without touching anything (the EPPM intake tube was easy to nudge down with some heat).

You might consider the VW spherical one used on the Kswaps, It might be able to go over the intake towards the firewall or where you have it. It doesn’t protrude downward nearly as much. It might be easier to run the hoses with the VW part.

 

[Lowtechprime]

Out of curiosity, what is that c635 trans out of? Will it mount to a SOHC by any chance?

 

[kmead]

Out of curiosity, what is that c635 trans out of? Will it mount to a SOHC by any chance?

The 635 is a modern transmission which is used in a variety of modern Fiat based cars. It can be found in the Jeep Renegade, Jeep Compass, Dodge Dart, Fiat 500L, Fiat 500X. Alfa Romeo Guilia and a few others in the USA. It is also the basis for the dual dry clutch automated transmission.

It is a modern 3 shaft transmission for transverse application which makes it shorter transversely and deeper longitudinally.

Like anything it can be made to fit… I am sure you could make it fit

No it isn’t intended to fit to a 138 based engine. The first biggest issue is it would put the starter on the exhaust side of the engine. The ratios generally available are decidedly biased towards economy and not sporting in my experience with our Jeep Compass.

 

[My1stCar]

Indeed, like the 635 gearbox, the 510 (that I have) has the starter on the inlet side. The Pratola Serra engine is a crossflow design with the exhaust on the front.

I made it more complicated for myself by opting for the Punto HGT's exhaust (same engine base and identical exhaust header). That one also has two catalytic converters, albeit smaller. It makes matters complicated because the O2 sensors stick out, which is why I had to make room by cutting, folding, bending and stitching it all back together with some added sheet metal:

No primer or paint yet, as it's too cold at the moment.

Same for the inside, when it's cleaned, sanded, primed and painted red it will look much better.

It does document the modifications better, tough...

 

[Dr.Jeff]

Those firewall mods are not nearly as extensive as I imagined they would be. I was picturing removal of the entire wall.

In your earlier pics it appears the rear bulkhead panel (between the engine bay and rear trunk) was not cut?

In retrospect, do you think with the use of a different exhaust manifold, perhaps a slightly different placement of the engine, and/or some modification of the rear panel, that the front firewall could have remained uncut?

 

[My1stCar]

Those firewall mods are not nearly as extensive as I imagined they would be. I was picturing removal of the entire wall.

In your earlier pics it appears the rear bulkhead panel (between the engine bay and rear trunk) was not cut?

In retrospect, do you think with the use of a different exhaust manifold, perhaps a slightly different placement of the engine, and/or some modification of the rear panel, that the front firewall could have remained uncut?

That's correct, the firewall between the rear trunk and engine is stock, no cuts needed there.

If one would opt for a cat-less exhaust (such as the Supersprint for the Punto HGT) less modifications would work, but the exhaust header needs some place at the upper region of the lower cross beam. The valve cover of the twin cam head needs the space I made at the top, specifically at the right engine lid hinge (the lower bolt interferes with the aluminium part of the valve train belt cover).

 

[KBabcock]

Actually I boxed all sides of the enlarged openings so hopefully it is at least as strong/stiff as it was originally.
Not shown are the custom air scoops that will be attached to the outsides of those openings...the new scoops are also MUCH larger than the stock ones. But all of this is definitely a non-stock looking mod, which my car is full of.

Would like to see how the new intakes look and integrate the lines of the car.

 

[Paolo]

Hi all,

I'm new to the forum, but have researched the wealth of information available with great attention because I recently pulled my first car out of its 20 odd years of storage.
My project is to swap a 1.8 16v engine and c510 gearbox from a 2002 Fiat Stilo into my X1/9. As far as I've seen this swap has not been documented, so I thought I'll give it a try.
The engine is the final evolution of Fiat's 4 cylinder naturally aspirated 1.8l Pratola Serra engine that was previous versions in the Barchetta, the Punto HGT and the entry level version of the Coupé. In the Stilo it delivers 133hp and 162Nm of torque, not the 160+ of the Abarth 1.4 (or more for the K swaps), but plenty of power to make the X even more fun to drive.

Marc,
Normandie France

Yep love your work can’t wait to see the end product bravo

 

[Dr.Jeff]

Would like to see how the new intakes look and integrate the lines of the car.

I don't want to get too far off topic here, but look through the thread below...I believe I showed the scoops mocked in place:

Side vents/ducts, and now Snorkels!

I don't recall this being discussed before (although I'm sure it has been at some point). This falls under the "customized X" category, so if you are a purist then you might go to the next thread now. :D I've been considering a custom "large intake duct" modification for the side vents (that...

xwebforums.com

 

[Lowtechprime]

Kmead said: "No it isn’t intended to fit to a 138 based engine. The first biggest issue is it would put the starter on the exhaust side of the engine. The ratios generally available are decidedly biased towards economy and not sporting in my experience with our Jeep Compass".
First off, I'd be considering it for a 128, plenty of room on the exhaust side for a starter, and I was thinking that with 6 forward gears, the ratios couldn't be that far apart, no matter how 'unsporty' they were..?

 

[kmead]

Kmead said: "No it isn’t intended to fit to a 138 based engine. The first biggest issue is it would put the starter on the exhaust side of the engine. The ratios generally available are decidedly biased towards economy and not sporting in my experience with our Jeep Compass".
First off, I'd be considering it for a 128, plenty of room on the exhaust side for a starter, and I was thinking that with 6 forward gears, the ratios couldn't be that far apart, no matter how 'unsporty' they were..?

128, 138 same same.

They are pretty unsporty, as in over driven on the top three gears. Finding info on these is pretty spotty.

Found it. 500L gear ratios. Intended for a turbo…

Gear Ratios
1st: 4.154
2nd: 2.118
3rd: 1.361
4th: 0.978
5th: 0.756
6th: 0.622
Reverse: 4.00
Final-drive Ratio: 3.833
Overall Top Gear: 2.38

There is a version of the C514 with 6 speeds, it is a standard configuration so longer than the 5 speed.

 

[My1stCar]

128, 138 same same.

They are pretty unsporty, as in over driven on the top three gears. Finding info on these is pretty spotty.

Found it. 500L gear ratios. Intended for a turbo…

Gear Ratios
1st: 4.154
2nd: 2.118
3rd: 1.361
4th: 0.978
5th: 0.756
6th: 0.622
Reverse: 4.00
Final-drive Ratio: 3.833
Overall Top Gear: 2.38

There is a version of the C514 with 6 speeds, it is a standard configuration so longer than the 5 speed.

That is much longer than the numbers I found for the C510 of the Stilo 1.8 16v:
1st 3.909
2nd 2.238
3rd 1.520
4th 1.157
5th 0.897
Reverse 3.909
Final 3.867

Which makes an overal top gear ratio of 3.47, only barely longer than the C635's 4th gear at 3.75, but with one more gear in between.

If I calculated correctly, the Stilo's C510 ratios with my tire diameter (562 mm) would mean I will have top speed at about max power. Not that I will drive that often, I need to keep my licence to be able to drive it
It also means relatively high rpms at highway speeds, ah well I'd better take the scenic small roads then.

 

[kmead]

That is much longer than the numbers I found for the C510 of the Stilo 1.8 16v:
1st 3.909
2nd 2.238
3rd 1.520
4th 1.157
5th 0.897
Reverse 3.909
Final 3.867

Which makes an overal top gear ratio of 3.47, only barely longer than the C635's 4th gear at 3.75, but with one more gear in between.

If I calculated correctly, the Stilo's C510 ratios with my tire diameter (562 mm) would mean I will have top speed at about max power. Not that I will drive that often, I need to keep my licence to be able to drive it
It also means relatively high rpms at highway speeds, ah well I'd better take the scenic small roads then.

In the EU I would expect a wide variety of ratios given the C510 and related transmissions were fitted to low displacement engines with relatively low torque. EU 500s came with a 6 speed manual so there is that.

Your project is looking good, that is a bunch of welding you have done to accommodate the exhaust. Can’t wait to see the next installment of what you are working on.

All the best.