Advice required for rebuilding an engine.

dcioccarelli

dcioccarelli

Dominic Cioccarelli
Hi all,

as the long summer days grow shorter, the time for doing serious work on an X grows closer.

I have yet to get any concrete advice on how I can improve the performance of my car, so apologies in advance for any repetition.

I have recently bought a US import FI car and am seriously unhappy with the performance (with respect to my previous euro spec 1500 carburettor car and my existing Australian 1300 cc car).

My conclusion (after asking and reading several threads) is that the issue is not so much the catalytic converter or the pistons but rather the head.

The constraint here is that I want to keep the fuel injection. Note that there was never a "euro spec" FI X1/9. So, the question is, how to achieve good (euro carburettor or better) performance whilst retaining the fuel injection?

  • I understansd that I wil need to shave the head. This, I assume, will mean (at the very least) new tappet shims. Anything else? I want to get close to 10:1
  • What about the cam? Have we any definitive answer about the best cam to run on a high compression FI engine?
  • I will probably loose the cat (until my next TÜV exam) but does this make a huge difference?
  • Megasquirt? Is it worth it? (I already have programmable ignition mapping, BTW).
  • What else can I do to make a tractable road car which will be reliable enough to use as a GT but will also have decent performance when required? FI, electronic ignition and emissions controls are a requirement...
I'll be having the engine rebuilt by an X1/9 specialist in Hungary, so my goal is to do the most that I can when the engine is out of the car. Remember that I want to end up with a car which is both fast, that can do 1500 Kms in a day (GT style) and can be driven in traffic.

Am I asking too much?

Cheers,
Dom.
 
Dom, you are on the right track....

I have built an engine similar to what you are proposing

The constraint here is that I want to keep the fuel injection. Note that there was never a "euro spec" FI X1/9. So, the question is, how to achieve good (euro carburettor or better) performance whilst retaining the fuel injection?

I built as close to Euro spec on my '81 as I could.

I understansd that I wil need to shave the head. This, I assume, will mean (at the very least) new tappet shims. Anything else? I want to get close to 10:1

Yes, you should be able to get 10:1 compression pretty easily by combination of milling the head and milling the block deck surface to bring the piston tops flush.

What about the cam? Have we any definitive answer about the best cam to run on a high compression FI engine?

Do not get fooled and put too hot a camshaft in the car. The very hottest that you want to go in a fuel injection car is a carb 1500 Euro cam. A better choice would probably be a 1300 Euro cam.

I will probably loose the cat (until my next TÜV exam) but does this make a huge difference?

Easy to switch it in and out. Beginning with a Euro style 4-2-1 manifold setup will help.

Megasquirt? Is it worth it? (I already have programmable ignition mapping, BTW).

Yes, MS is probably worth it, but there is a learning curve, which can be considerable.

What else can I do to make a tractable road car which will be reliable enough to use as a GT but will also have decent performance when required? FI, electronic ignition and emissions controls are a requirement...

Find a Ritmo final drive gear set. It allows you to use the torque of the 1500 motor and lowers your RPM by about 500 at any given speed.

And, to the subject of your transaxle, when you go through it polish the shafts so that they run really smooth. Make sure all of the shifting blocks line up well. Ensure that the bearings are totally smooth running, and the synchros and rings are in top, top shape. And run your choice of Redline MT-90 or MTL.

Follows is a brief description from when I put it up for sale of what I built up on my '81 X. Paulienoodles is driving the car now, and seems really well pleased.

Engine condition excellent. Head leak checked and valve job 2000 miles ago. Head milled to give 9.3:1 compression. All ports matched and throttle body bell mouthed. Abarth intake and exhaust valves. PBS SX-1 cam set to 1 degree advance. Cam was ground on a new blank; it is not a regrind. Fuel injectors replaced with spare set and all FI hoses changed 5000 miles ago in 2005. Exhaust manifold smoothed inside. New oxygen sensor in Feb ’06. Catalytic converter. 2 inch exhaust system with turbo muffler. Muffler 2 months old. Cooling system rebuilt in August 2005 and features welded aluminum coolant tank configured for Stant cap. New OEM radiator and rear coolant hoses at the same time. Original canister type air filter included.

Chassis condition excellent. IAP springs, KYB GR-2 shocks, semi-metallic brake pads, braided teflon brake hoses. Front Addco style front sway bar mounted to underside of trunk instead of trailing arms. Speedline Iron Cross wheels, with bolt on valve stems. Sumitomo HTR-200 tires, 185/60 tires with 8000 miles. Aligned to 1/8 inch toe in both ends. Motor mounts good.

Transaxle condition excellent. 1st, 2nd, Reverse slider replaced 2001. 3rd & 4th gear synchros and slider replaced in Feb.’06. Equipped with Strada/Ritmo 3.59:1 final drive gears. MT-90 transaxle lube. Reverse gear has a chipped tooth on cluster shaft, so it whines. PBS lightened flywheel. Shifting is sharp and crisp.

So, is that what you are looking for? Oh, and try to hook up with Ulix. I think he is in Stuttgart, and will be a fantastic resource for you.

Ciao,
 
Dom,

What you're wanting to do is pretty much identical to what i'm doing now to my '85. Don't have time to write it all down right now but will later. In the meantime, could you and would you be willing to acquire a used Euro head and maybe even cam?

I think you're better off starting with the Euro head so you've got more room to unshroud the valves and still wind up with a decent compression ratio without having to cut the head so much. And a Euro 1500 cam might well be an excellent an economical choice if you can get ahold of one for cheap.

Another option would be to retain the US head but instead bump the displacement and compression through use of a 1600 crankshaft. That's exactly what I would do if I had access to the crank.

///Mike
 
Euro head?

Hi Mike,

thanks for the input, but when you say:

///Mike said:
Dom,
I think you're better off starting with the Euro head so you've got more room to unshroud the valves and still wind up with a decent compression ratio without having to cut the head so much. And a Euro 1500 cam might well be an excellent an economical choice if you can get ahold of one for cheap.
///Mike
Click to expand...

I agree that the Euro head is much better (and I can get one easily) but I can't have a Euro head with fuel injection. Note that even the FI cars sold here were basically US cars. Unless I am missing something and it is possible to retrofit fuel injection to a carburettor Euro 1500 head...

Cheers,
Dom.
 
Yes, you can use a Euro head on an FI motor-- that's what I'm doing right now.

The functional differences are the reliefs in the ports for the fuel injectors, the mount for the auxiliary air valve, and the hole for the thermo time switch.

You can easily notch the ports for the injectors-- many have done this when fitting an 100 or 1300 head to an FI car. I plan on making a bracket for the aux air valve that sandwiches between the head and the thermostat housing.

The thermo time switch is not as easy to accommodate, as there is no extra boss on the Euro head which can be drilled to accept the switch. A couple of options come immediately to mind though-- you could make a T fitting to mount both it and the sender for the temp gauge. Or you could simply install a momentary push button switch in the cabin, which is what I've been thinking to do. The thermo time switch only controls the cold start injector so it doesn't come into play very often where I live. Maybe someone else has a better suggestion?

In any event, not all that much trouble to retrofit a Euro head. But like I said before, if you have easy access to Euro parts the crank would probably be easier still, and would make more power.

///Mike
 
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