'77 Fiat X1/9: This is all your fault GRM.

I just found this thread, nice work!  I still miss my X1/9's. 

Just to clear up a couple of items.  I had a set of 40 DCNFs on my '74, and they fit just fine under the standard 1300 engine cover, even with the rain tray.  It had at the time an ITG air cleaner, so your results may vary if you used a taller version.  If you did go to dual carbs, make sure you go with head work and a cam, as otherwise it's just too much fuel to run correctly.

When I updated to a 1500 I had to use the 1500 engine lid.  The block is a bit taller on the 1500 is the reason, not the carb setup.  Everyone is correct on the control arms needing to be changed, it also wouldn't hurt to update the hubs as the wheel bearings are stronger in the 1500 cars.  The 4 speed transaxle is a bit stronger than the 5 speed however, but you did get a drop in revs.  Reverse is a real weak point on the 5 speeds.  Go very easy on reverse when you use it or sooner rather than later you will be holding it into reverse when you try to use it.

In reply to racerdave600 :

I've heard that putting it first or second before trying for reverse helps.

I drive classic SAABs, so I know a fair bit about gingerly transmission use. Full stop, double de-clutch, and first gear before ever engaging reverse. Not exactly necessary, but it never crunches when I do this.

Thanks for the input Racerdave- whether the DCNF clear or not, I'm not afraid to cut metal for some long velocity stacks if that is what the dyno dictates to get the power band where I want it. Head is ported and has a FAZA 40/80.

If you make it to the challenge and Steve Hoelscher is one of the pro drivers, look him up.  Although it mostly sits in the garage these days, he still owns his DSP multi national championship winning X1/9, and it is an amazing car to drive.  The best autocross car I've ever driven, by far.  There's probably no one in the country with as much X1/9 knowledge as he has, and it would be well worth it to pick his brain for a bit.  His suspension set up is a bit unorthodox, but one drive and you wonder why you would ever do anything else.

To Stefan, that does help, but I also never let the clutch fully engage in reverse, keeping the torque off of it as much as possible.  Just get it rolling by as little engagement as possible.

A big plus one on using Hoelscher as a knowledge resource. His X1/9 was epic in DSP until it finally got outclassed by more powerful cars. Then, he took his mid-engine set-up know how and driving skills to D-Prepared(?) with a spectacular first-gen MR2.

Thanks guys! I want to attend the Challenge someday, but it won't be this year. Hoelscher is already a source for sure - I'm reading his five-speed bible right now as I look through by heap of trans parts.

Hopefully I can get a chance to meet him!

Flywheel lightening

I got two flywheels from a Fiat friend as mentioned earlier in the thread. The deal was I could keep one if I returned his to him lightened. So lets start with a stock weight:

This old kitchen scale looks crusty, but the weight it registers is about the same as what the internet told me the stock flywheel should weigh. 16 lbs, 2 oz.

Next to chuck it up on the lathe. I restored this old ~1944 Logan lathe a few years ago, and it's one hell of a machine for a hobbyist like me. You can see I started with my three jaw chuck in this photo:

Clearance was super tight - this is definitely the largest flywheel I'll ever turn on this ~11" lathe. Another 1/8" and I would have been paying to have this work done.

First thing I noticed is the large amount of runout I was seeing. The flywheel visibly wobbled radially when I ran the lathe. After a shifting it on the chuck a few times, I realized I needed to switch to my four jaw chuck to get the accuracy I needed. This flywheel will spin to almost 8k RPM on the engine, so accuracy is probably important. The jaws on a three jaw chuck all turn together when you tighten them up. They're ok for accuracy but you get what you pay for. Mine is old and kind of cheap and apparently not accurate when tightened on the ID of a flywheel clutch disc surface. Four jaw chucks have each jaw tightened independently, so you have to use the jaws to manually center the work using a dial indicator. With the four jaw, I was able to get it zeroed to the pilot bushing hole in the center of the flywheel down to .005mm. I'm not a machinist, but I feel like I got this as accurate as I possibly could with my equipment.

The manufacturing tolerances on these flywheels surprised me - they were out of round from the factory by about .050". I really was torn between zeroing the flywheel to the outer edge, or the center hole where the flywheel seats on the crank snout. Since they will still need to be balanced before use, I opted to use the center hole since in my mind it is better to be concentric to the crank than some arbitrary cut made in Italy 40 years ago. I really hope this was the right choice. If they come back from the balancer with issues, then I'll recut the backs concentric to the outside instead of the crank I guess.

First few passes made:

Turning this cast iron was a bear. It required the upper limits of torque the lathe could produce, and the tooling absolutely screamed wet or dry. I played with some different cutting tools, feed speeds, depth of cut, and eventually found it cut best as slowly as possible. Back gear on the lathe, and slooooow cuts with a small carbide insert. It would cut pretty deep passes if it weren't for the fact I was operating at the max power on the machine and I could still stop it cold if I tried to take too much. Here's a before and after of the two flywheels:

There was plenty of meat to remove from the flywheel without coming anywhere close to creating any structural issues. On the engine side of the flywheel is where all the cuts were made, and these things had a very broad sweep of iron getting progressively thicker the further out toward the starter ring you went. This iron was there to support the ring and to add weight. The starter rings needs to be supported, but could do with far less meat. I kept the removal pretty conservative overall - I've read about people taking stock flywheels down to 12 pounds, but I can only assume that would require some drastic measures. Catastrophic flywheel failure is not something I want to explore.

Here are the two finished flywheels:

Additional work included lots of cleanup. They were both rusty and gross from years of use, so I gave them an extensive scotchbrite pad treatment. One of the flywheels had a few starter teeth that needed a little love with a file to clean up some burrs. I also chased the threads on all the holes with a tap to ensure they were clean. This was a much needed step - the threads were gross on both flywheels. I gave the clutch disc surface a fresh surface too - one had been recently resurfaced and didn't need anything but some gunk removed from it.

Final weight: 14lbs 1oz.

I made a little video of the whole process. Two pounds of cast iron taking small cuts on each pass takes forever. It was at least three hours of lathe time for each flywheel.

https://www.youtube.com/embed/-zWDGXvz6g0

They say you've got to learn to choose your battles.

I was really hoping to rebuild this transmission myself. I travel for work, and lately the travel time has been in the neighborhood of 75% on the road, which is a far cry from the 25% I was told when I started with this company a bit over two years ago. As a result, my personal struggle is between doing this trans rebuild myself knowing that it would likely take me the better part of a year to complete *OR* pay to have it done to keep things moving. I'm electing to have it done by the master himself: Steven Hoelscher, so that meant shipping the damn thing all the way across the country.

One of the reasons I wanted to rebuild it was to get intimately familiar with how it works. Fortunately I had to assemble the trans from a box of parts - this was the coolest puzzle I've ever done, and I did it without cheating and looking at a manual.

Fortunately it seems to only go together one way. Upon close inspection, the fifth gear on this box is trashed. I'm worried about the cluster gear shaft because the woodruff keyway has some pretty bad damage. You can see it at the top right of the above photo.

Figuring out the shift shafts was the best part of the puzzle. Some pretty clever engineering went into this little box.

Once I got it all together again, it was time to get a weight to see what I was dealing with for shipping. Looks like ~62 pounds (the scale goes up to 150 - you just have to keep track of the number of times the needle goes around the scale).

$30 at Home Depot got me the supplies I needed to build a little crate. It's a bit much, but I'm worried about shipping this thing all the way across country.

Extra GRM points: for the UP stencil, I used the last of the can of wrinkle red that Hungary Bill gave me before he moved to Kuwait.

Your shipping crate makes me irrationally happy. Nice work!

Thanks Ransom!

In other Fiat related developments, these are in the mail all the way from the UK:

After months of watching eBay, someone finally posted a NIB set they never got around to using so I managed to save a few hundred bucks over new.

Now to get my cam position sensor and crank position sensors sorted out.

Jenvey DCNF throttle bodies came! I was so excited I skipped out of work for the afternoon to poke around in the shop. Temporarily mounted them up to my intake manifold and slapped them on my hill climb motor. I'm thrilled to report that the bore spacing of my manifold just so happened to match the throttles I bought. Success!

Then I started looking into how I could come up with a cam position sensor. This engine later had a cam driven distributor, so there is a removable cap at the end of the cam. I wheeled my 1500 motor (courtesy of Stefan) to see if it was any different. The end of the cam is smooth, so it doesn't look like a great option. I won't be using the block mounted distributor on this motor though, so I could rip an old distributor apart and make a cam position sensor there. The third option would be to create a flag on the cam sprocket and make a sensor bracket to read the flag. Either of the last two options are looking pretty good right now.

Here's my fiat engine collection:

The intake manifold will need a little time with the die grinder to make the ports match:

To do list for the engine and engine management:

1. Crank position sensor and trigger wheel. Burrito has a set for me...need to bug him.
2. Cam position sensor: I'll poke around with my spare distributor to see if I want to go that route. I also need to order an adjustable cam sprocket and see if it might be easier to make a trigger flag on it for a sensor to read.
3. Throttle position sensor: Jenvey is all set up for a TPS that was common on Rover engines...an engine never sold here in the states, so a TPS is like $50 at best. I'm going to order a GM sensor to see about adapting one with a bracket since those are cheap and plentiful.
4. Oil pump: need to take the sprocket off the one on the hill climb motor. It's either mounted backwards or the wrong one for this engine because it isn't aligned with the other sprockets.
5. Order a clutch assembly to go on my newly lightened flywheel.
6. Assemble all the ancillaries on the motor. Water pump, alternator, belts. I'm considering engineering up a serpentine belt arrangement to ditch the V belts and possibly open doors for belt driven forced induction options down the road.
7. Modify the rear control arms OR find some >79 control arms and rear knuckles.
8. Once the transmission comes back, I can bolt it all together with the starter. Then there's no reason not to get it installed!

I have some serious induction envy.  That is going to make some really incredible noises!

I still have that pile of parts sitting on my workbench for you, including a cam driven distributor and the matching cam.  It's probably not a terribly hot cam, but an enterprising gentleman could probably copy the distributor drive portion to a different cam if he had assorted machine tools. 

The crank sensor and related bracket are still bolted to the engine that is currently in the 128.  I'll see about pulling them off this weekend since the weather looks to be pretty prime for driveway wrenching.

If you need to free up some space, I will totally take that injected 1500 off your hands.  

In reply to Burrito :

Sounds like we've got the makings of a date...and maybe a trade. I don't know much about this 1500, and I don't recall Stefan knowing much either. It's marked '85, and there's also a rebuild tag on one of the freeze plugs. I turned it over yesterday and it made compression twice each rotation, so that's a pretty good sign. Part of me wants to hang on to it to add snail power somewhere down the road...the other part wants it out from under my bench.

Should I plan a road trip for a weekend in the near future?

Mezzanine said:

In reply to Burrito :

Sounds like we've got the makings of a date...and maybe a trade. I don't know much about this 1500, and I don't recall Stephan knowing much either. It's marked '85, and there's also a rebuild tag on one of the freeze plugs. I turned it over yesterday and it made compression twice each rotation, so that's a pretty good sign. Part of me wants to hang on to it to add snail power somewhere down the road...the other part wants it out from under my bench.

Should I plan a road trip for a weekend in the near future?

Bought off eBay from a salvage yard in Florida, so likely in ok shape, but probably should be poked, prodded and lightly freshened before serious usage.

That intake setup is thexy and I’m glad to see progress on the lil exxy.

if you guys get together and want a third wheel to point and laugh, let me know.

Look what's back already!

The new transmission is beautiful. It's pretty clear Steve H. has done a few of these.

I'm going to be on the road for the next 2.5 months; just home for a day or two a week if I'm lucky. So the next step of pulling the existing engine will have to wait until April.

Any update on the new transmission?

GIRTHQUAKE said:

Any update on the new transmission?

I'm on the road for work for the rest of the month...and half of April at this point, so it's just sitting in the shop, right where I left it shown in the photo above.

I did just spend a chunk of change on a new clutch and fuel tank and some other parts I needed...so when I actually get some time I'll have the stuff I need.

The one and only GRM famous Burrito and I have a date for the end of the month...he's going to come out and help me put my new motor in.

So I suppose I need to get the old one out first, right?

Parts have been ordered. Let the thrashing begin. I know we're not supposed to post porn on here, but I couldn't help but share this one tasty peek:

The population of Bonertown just went up by 1.

Wow.  Now that's just thexy for the exxy....

If you need another set of helping hands attached to an idiot let me know, I can probably make it up your way.

Good god are you planning to run that at redline all the time? With that header that's about where you'll have to be to make any power.

In reply to brad131a4 :

The header is from Vicks and is just about the most common X1/9 header on the market these days. That said I'm not satisfied with the collector arrangement, so I'm planning to rework the lengths a bit too. It'll probably end up as a tri-y configuration. I picked this steel header up locally for a song to play with too:

Engine is out. Things are happening! Pics to follow shortly.