Widget 0 Posted February 7, 2008 Afteroon all. First post for this newbie; I'd be grateful for your help and guidance. I'm looking at two TU 1360 engines: One with an Iron block (UK Rallye) and one with an alloy block (from an XS). My understanding is that the alloy engine is substanitately lighter - circa 20kg. However, I've read posts, which infer that some people prefer the iron block. Firstly, would anyone be kind enough to enlighten me as to the reasons (durabaility? reliability? performance?) why the iron block might be preferred by some. Secondly, given the choice to re-build and 'enhance' the head and cam of the iron or alloy engine, which would you recommend...and why? Many thanks Widget Share this post Link to post Share on other sites
DrSarty 90 1 Cars Posted February 7, 2008 Hi Widget & welcome, First off... I've read posts, which infer that some people prefer the iron block we imply, you infer As with all things in life it's a matter of compromise. Iron blocks whilst heavier are very durable, don't corrode like alloy ones can and are open to easier methods of rebore for upped diplacement . This can be done with alloy blocks by way of different liners, but I believe the complexity and cost goes up to. And forged pistons ain't frickin' cheap! Were I to choose again I would stay alloy to save weight. Many people comment that it doesn't make a difference, but it must as the laws of physics say it must. In practise though they are right, as unless - and you haven't stated your engine application - you were going balls-out racing, those extra kgs probably won't matter. A GTi6 XU engine is a perfect example. My answer is a bit generic just relating to iron vs alloy, but is my 2p worth. Sandy309 is extremely knowledgable on TU engines having created some screamers. Head work needs specific advice as some are fine as is, and you may either waste money for very little or no gain, or even lose performnace. And it can also be a road into nowhere, as one mod depends another mod to get the benefit. It unfortunately very often relates to the depth of your pockets and how long your arms are. You'll get proper technical answers off other people here I'm sure; but that was my philosophical, down to earth harsh reality bit. Good luck and welcome again. Rich Share this post Link to post Share on other sites
Sandy 191 Posted February 7, 2008 I prefer to build alloy 1360s and save the 23kg difference in built up weight, but there's alot more to go wrong, building an alloy block TU and if you don't have the budget to use a high proportion of new genuine parts, consider buying a late low mileage alloy 1360 (such as the ET3 16v engine) to re-build into an earlier block or simply drop a head on. Going with the Iron block gives you a better choice of bore sizes and capacity, along with machining processes being much simpler. With the exception of the 1.4 XSi Iron block (thinner cylinder walls), they can usually be safely bored to nearly 80mm. The cranks from 1.1 to 1.6 all fit (69mm, 73.5mm, 77mm, 82mm). Share this post Link to post Share on other sites
DrSarty 90 1 Cars Posted February 7, 2008 As Sandy says, a very flexible engine indeed. If you haven't read about this TU build, then you ought to. Share this post Link to post Share on other sites
Widget 0 Posted February 7, 2008 DrSarty, Sandy309, thanks to both of you for your thoughts on this and your welcome to the forum; it's much appreciated. Not just a technical education either; a little Hobbesian philosophy and a grammar lesson thrown in for free - I really will better myself on here! I've come away with the feeling there's no 'nailed on' better choice out of the two. Any potential regret will probably be due to choosing one engine over the other for the wrong reasons. I'm almost sure you've helped me make the definately maybe right choice... Thanks again Widget Share this post Link to post Share on other sites
NeilGTi85 5 Posted February 20, 2008 Hello all, When i was looking for my MI 16, i went to see a alloy and iron. Both in about the same conditionbut i went for the iron. Reason's being it was about 50% quiter inside...and also had the 16v loom instead of the std loom converted....which the alloy one had. (did not notice the weight diffrence at all) So far its been very good, i have been exploring my options for getting more bhp's and have found with an iron block you have more choice. I am looking to bore it to 88 and fit some bigger valve's etc.....or turbo it, Neil Share this post Link to post Share on other sites
