Marco79 Posted April 21, 2013 Share Posted April 21, 2013 Are NA camshaft caps the same as TT ones? Are they interchangeable? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 23, 2013 Share Posted April 23, 2013 NO NO NO, they are matched and line bored to the head, and must stay with the head they came on, and stay in sequence (numbered) order. Same as big end and main bearing caps!! Quote Link to comment Share on other sites More sharing options...
Marco79 Posted April 23, 2013 Author Share Posted April 23, 2013 NO NO NO, they are matched and line bored to the head, and must stay with the head they came on, and stay in sequence (numbered) order. Same as big end and main bearing caps!! I have a head without any cam caps surely I can get them replaced? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 23, 2013 Share Posted April 23, 2013 No, the caps are line bored and honed to the head in manufacture. It's effectively scrap I am afraid sorry. Other caps *COULD* be fitted and line bored, but the cost would be huge, *FAR* more than another head. Quote Link to comment Share on other sites More sharing options...
james_cbr Posted April 23, 2013 Share Posted April 23, 2013 NO NO NO, they are matched and line bored to the head, and must stay with the head they came on, and stay in sequence (numbered) order. Same as big end and main bearing caps!! so how do people fit titan main caps ? Quote Link to comment Share on other sites More sharing options...
Marco79 Posted April 23, 2013 Author Share Posted April 23, 2013 No, the caps are line bored and honed to the head in manufacture. It's effectively scrap I am afraid sorry. Other caps *COULD* be fitted and line bored, but the cost would be huge, *FAR* more than another head. Are the caps themselves the same tho in essence? For example say I did have them honed could I use NA cam caps? If in the future I wanted to upgrade the head is there anything that could be done? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 23, 2013 Share Posted April 23, 2013 (edited) james_cbr: They have to have the block line bored and honed by one of the VERY few companies in the UK capable of doing this. It's commonplace in the USA, but over here it's costly and a lot of places do not do it correctly and you get a scrap block back. I have just done this for a customer, if you can possibly avoid steel caps it's far safer. In manufacture Toyota have a dedicated machining centre, at HUGE cost, for each engine family. Line boring "a block" is rarely as accurate as a manufacturer will achieve in production, unless you have F1 style budgets, and access to places like Engine Developments. Edited April 23, 2013 by Chris Wilson (see edit history) Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 23, 2013 Share Posted April 23, 2013 Are the caps themselves the same tho in essence? For example say I did have them honed could I use NA cam caps? If in the future I wanted to upgrade the head is there anything that could be done? I believe N/A caps, except the front ones, are probably the same. Trust me, if you have no caps with the head, it's a scrapper. I have several here I use for cutting up, or for spare caps and collets and valves. If you are thinking what I think you are thinking, stop! Just get a TT or N/A head complete. Quote Link to comment Share on other sites More sharing options...
Marco79 Posted April 23, 2013 Author Share Posted April 23, 2013 I believe N/A caps, except the front ones, are probably the same. Trust me, if you have no caps with the head, it's a scrapper. I have several here I use for cutting up, or for spare caps and collets and valves. If you are thinking what I think you are thinking, stop! Just get a TT or N/A head complete. What you mean a half round file isn't the right tool to match the profiles........ Seems a massive shame to class a perfectly good Tt head as scrap I have another compete head but was hoping to use this head as the for upgrading, machining etc while still being able to run the car. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 23, 2013 Share Posted April 23, 2013 (edited) I have several TT heads with no caps, and there's no way it's cost effective to attempt a repair. If they were ERA or Bugatti heads, different matter! For the record, NEVER buy heads with no, or mismatched, cam caps, nor blocks with missing mains caps, unless you intend having the block and a set of steel caps machined to fit. The caps need to stay with the donor head, or block (or con rods), and remain in their numbered order. The caps are stamped with their position number. 1 is at the front E1 is exhaust cam, number 1 cap. I1 is inlet cam front cap. It matters which way round they go, they have an arrow on them pointing to the front of the engine. They need evenly torquing, they need checking for wear, which is more likely in the cap half due to lobe thrust. Buy a genuine workshop manual!`Some people will happily spend a fortune on chromed bits, then try and be a cheapskate over the (high) price of a genuine assembly manual. RTFM!!! There's a LOT to know and learn about engine assembly, unless it's your day job you NEED a manual. One saved mistake and it's paid for... Edited April 23, 2013 by Chris Wilson (see edit history) Quote Link to comment Share on other sites More sharing options...
Marco79 Posted April 23, 2013 Author Share Posted April 23, 2013 I know about the order and placement of the caps etc i also knew about the crank caps but hadn't appreciated the camshafts were to the same tolerance as i thought there would have been a part produced to a nominal size that would suffice. We can produce parts like that to a nominal tolerance for aircraft engines but obviously the car industry isn't there production wise. Ah well live and learn! Cheers for the help Chris Quote Link to comment Share on other sites More sharing options...
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