Race Engine Forum UK

Hello,

I have just joined the forum. I have recently aquired an X1/9 1300 Lido and was wondering if you could spare some time to help me with ideas for a 'hotter' engine. Basically I don't want anything too extravagant and I want to keep it a 1300 but I want to improve performance.

Hope you can help, thank you

Adam.

Staying with the 1300 isn't a problem at all, the question is how far do you want to go?

For modest road use you can still extract a healthy power figure and very brisk performance for the X1/9.

Personally (and keeping it brief) I would start with replacing the original rods and pistons with forged items and raising the compression ratio a little at the same time. Balance the bottom end to monopolise on the revvy nature and you have the beginnings of a winning formula. The head is fairly good to start with but needs some porting and polishing with the inlet valves enlarged. For the exhaust manifold I would recommend a copy of the Abarth system, for the induction side you need to chose if you want carburettors or throttle bodies. For carbs you will need a pair of DCNFs or equivalents as the side draught carbs simply don't fit without butchering the boot and that would be a very sad thing to do to a Lido. Throttle bodies tend to be more compact and you may find they fit just fine. An off-the-shelf inlet manifold can be tricky to source but having one made isn't. The choice of camshaft is down to personal taste, we've developed a couple with the aid of Piper that gave excellent results but were really intended for racing but there is certainly a fairly broad range to choose from.

What you are left with is some knock-on effects. The top engine mount will need to be changed for something a little stiffer. The bottom engine mount will need to be kept in near perfect condition - on your car this means a new item at the least as you can be sure after 30 years the big rubber bush is not up to the job. Strangely the side mount is likely to be ok although I would still recommend replacing it.

The gearbox is your last big hurdle, the 1300 box will handle a surprising level of torque but only if it is in good condition to start with. The driveshafts however will not. A set of custom made driveshafts is relatively cheap and makes sure you have no major disasters. The rest of the gearbox will need treating with kid-gloves still - it is likely the most significant weak point in the entire drivetrain. Most people I know have opted to use a relatively lightweight clutch in order to create a controlled point of failure. The alternative is an expensive gearset or if you are feeling like the need for an extra gear is overwhelming I would suggest a later 1500 5-spd (this requires a different LHS wishbone and the later driveshafts) which gives you the opportunity to use the tougher (early) uno turbo internals.

This all sounds like a lot of work, I'm sure, but it gives you a very strong and capable engine that retains the versatility of the original. The power hike while modest in actual bhp figures is still significant - between 30% and 40% and unfortunately that generally means some fairly thorough work to ensure reliability. I really do not believe in building a tuned engine if it only works for a few days at a time and certainly wouldn't want to encourage such things in others.

Some good advice there Julian.

Worth knowing that the flow gains from porting, seat and valve work and deshrouding are very significant. That's where I would put my money, do the head if the bottom end is in good shape if the budget was limited. The gains in airflow mean more torque and power, bhp, say, could typically go up by 12 or more on the X19 1300 with vastly superior throttle response. And she will pull higher rpm too. I have not enlarged the ports by much, about 1mm typically.

Graph below is the similar SOHC Tipo 1.4 head, same valves but doesn't flow as well as the X19 in standard trim because the smaller bore shrouds the inlet valves quite badly, but good gains can be had if done with care.

The inlet manifld in this case (for rallycross in Eire) is a single one for 40 DCNF Weber carb, bigger than the stad X19 1300 carb by a big margin so less restrictive, but gains will still be very real on the standard carb, BUT to make sure I certainly would be for fitting a good tubular race header and silencer. What's available? That I don't know, I don't trade in exhausts.

I'll post some photos, they are on another computer.

GC

Hello,

Well thank you both for such a comprehensive reply to my question. I have decided that I need to consentrate on the head as I am sure I am unable to afford all of the suggested work in one go. I think porting and polishing the head as well as adding better carburation and a more efficient exhaust manifold would be a good start. I believe C.S.C. make a Primaflow performance exhaust and manifold for the X1/9 but I have yet to hear of any comments on the quality and performance. I am completely open to suggestion on this subject as I myself have very little experience with building engines. What sort of price will I be looking at for the suggested head work? I need to ensure I can afford the work before I go any further. Thank you,

Adam

You'll have to email on price Adam,

I apply the same rule to everyone incl myself, no quoting of any prices on this site (except sales and wants!)

GC

I have tried the CSC system but only on an otherwise stock engine and that was a 1500 too so I don't feel that the results would be representative of what you would experience on a 1300.


I know more than a few people who have been astounded by how high their 1300 engines will rev reliably but this has been a matter of luck rather than judgement as the consistency of production from the factory is not particularly good.
In short some engines will rev forever while others seem to run out of steam quite early on. I've put this primarily down to the quality of balancing (or rather the acceptable production tolerances) maintained by Fiat but there is an issue with some blocks twisting bringing the crank slightly out of alignment with the bores.
It is a fairly rare thing to see on the older engines but the later forced induction engines (which tended to get that much hotter) have a very pronounced problem in this respect that really saps power.

Some pictures of head prep, as I said the Tipo SOHC and X19 heads are very similar.

GC

Very clean work Guy. I must admit I have never really seen any of your work until I saw my friend Bernie's Volumex engine you rebuilt for his Lancia Montecarlo. I am still urging him to install it. I have spoken to a few people about the work you produce and have heard nothing but praise and reassurance. I will make a point of calling you when its convenient so we can discuss ideas and you can pass on advice. Thanks to those I spoke to I have absolutely no doubt that my engine will be in the safest of hands. Julian, I must say that the spec you offered has really helped me in deciding how far I want to go. I have decided on cylinder head work as I am not looking to build a full spec engine. I wish to mildly tune the car as it will only be for road use (for now!). Thanks again,

Adam