blade7

When installing dry liners into a 3.0 block are the windage port cut outs machined into the liners before or after installation ?. Thanks.

blade7

Before would be easier I'd guess, nobody has an opinion/experience ?.

333pg333

https://rennlist.com/forums/924-931-...r-400hp-4.html

blade7

Thanks for the link Patrick, I think the liners fitted to turbotim's 2.7 16v turbo had to be machined for the ports after fitting. I cant see a pic of the underside of the block in the link to tell exactly how far the liners extend down into the block ?.

Paul.

333pg333

I can't say from direct experience as the ones in the bigger motor are in a 2.5L block. I'll see what I can dig up Paul.

blade7

Thanks Patrick,
The shop that installed turbotim's liners are now quoting nearly twice as much due to having to machine the liner cut outs in situ .

fortysixandtwo

The ports should be one of the first features machined. If done after the bore has been machined, it would be difficult to impossible to machine without distorting the bore.

When my 3.0 dry sleeved motor was going together, Darton forgot to add the windage holes. Initially they said to just machine them before installation. After it was deemed to be not worth the risk of distortion, they were shipped back to Darton, for them to do the machining. Darton ended up tossing my original set and machining up a new set.

blade7

Sorry I'm a bit confused, are you saying the sleeves should come with the port cutouts already machined out ?.

fortysixandtwo

The ports should be made before the sleeves internal and external dimensions have been finalized. If you're going to set the bore size after the sleeves are pressed in, it'll probably be okay. I don't know how much work has already been put into your sleeves, but in my case, the sleeves had already been machined to the rough bore size, where a finish hone is all that would have been needed to get to the final bore size.

Clamping the sleeve, to be milled, will still be tricky. Possibly someone here has had good results making the ports after pressing the sleeves in, but my experience is that this is done before installation.

Chris White

I would machine the windage ports before installing them. They do not have to be an exact match. For bonus points you could radius the ports for better air flow!!

When dry sleeving make sure that the machine shop is familiar with the proper technique - other wise the sleeves will eventually sink into the block!

blade7

Thanks for the replies, I understand now. I haven't commited to sleeves just yet, I'm still comparing the cost of Alusil v sleeves. I'm going to ask some machine shops how they install sleeves, I've heard of a .003" interference fit and chilling the liners in a freezer to fit, I thought heating the block and chilling the liner was the best option ?.