205Rallee 59 Posted January 14, 2008 My TU24 has now been stripped down and have found out that the head which had been "modified" by a certain Peugeot Tuner, was completely standard apart from a light butchering of the inlet ports, a few chunks out of the valve guides and a fair old skim of the head. The cylinder head is now being modified properly. The standard bore is 74mm(?) and mine is currently fitted with standard 75mm pistons. I've been advised to bore the liners out to 76mm using Wossner forged pistons. Will the liners cope with being bored out to 76mm? Share this post Link to post Share on other sites
Sandy 189 Posted January 14, 2008 Standard bore is 75mm. The liners are pretty thin at that. I haven't tried 76mm yet, because I'm not convinced the liners are thick enough at 75mm TBH! Boring them accurately and keeping the shape when compressed under the head would worry me. Share this post Link to post Share on other sites
205Rallee 59 Posted January 14, 2008 Standard bore is 75mm. The liners are pretty thin at that. I haven't tried 76mm yet, because I'm not convinced the liners are thick enough at 75mm TBH! Boring them accurately and keeping the shape when compressed under the head would worry me. Is it worth the effort/risk? Ispoke to a guy from Jaquemin Tuning at the Autosport show last week and he said there would be no problem as the liners are very strong. Not sure if If I want to risk it for the extra cc's! Share this post Link to post Share on other sites
christopher 5 1 Cars Posted January 14, 2008 (edited) My TU24 has now been stripped down and have found out that the head which had been "modified" by a certain Peugeot Tuner, was completely standard apart from a light butchering of the inlet ports, a few chunks out of the valve guides and a fair old skim of the head. The cylinder head is now being modified properly. Be careful. As I'm sure you know, this head flows very well out of the box. And as with many other TU's its very easy to end up in a loss in flow on the bench rarther than a increase. However saying that an increase of at least 16% is possible. Do you have any pics. Would be interesting to see what said tuner did to the ports.. Edited January 14, 2008 by christopher Share this post Link to post Share on other sites
205Rallee 59 Posted January 14, 2008 Be careful. As I'm sure you know, this head flows very well out of the box. And as with many other TU's its very easy to end up in a loss in flow on the bench rarther than a increase. However saying that an increase of at least 16% is possible. Do you have any pics. Would be interesting to see what said tuner did to the ports.. The inlet ports looked like they'd been attacked by coarse sand paper and the valve guides literally had big lumps chewed out of them where the tool they had used hit the guides. Not pretty and a waste of a lot of money! The head is now with Longman Racing who have done a few of these heads and fortunately the head is not a basket case. But it shows that you can't trust anyone, I only heard negative comments about them after I used that particular firm. I would love to say who they are but they'd probably sue me! Share this post Link to post Share on other sites
christopher 5 1 Cars Posted January 14, 2008 The inlet ports looked like they'd been attacked by coarse sand paper and the valve guides literally had big lumps chewed out of them where the tool they had used hit the guides. Not pretty and a waste of a lot of money! The head is now with Longman Racing who have done a few of these heads and fortunately the head is not a basket case. But it shows that you can't trust anyone, I only heard negative comments about them after I used that particular firm. I would love to say who they are but they'd probably sue me! Whats the brief are they giving it the full monty? Take some good pics when you get it back, be very interested in what they do and how much they can improve it:-) Share this post Link to post Share on other sites
