3.9" bore Rover

[NixVegaGT]

I figured I should start a new thread for this project. I'm doing my best to stay on track with this but I've got a job and kid to distract me so it may take a while. For those who don't know. This concept grew out of a number of threads where we ideated ways to increase bore beyond the Rover limits. The criteria, for me, is that the solution should be feasible and achieved with some welding knowledge.

Where I landed, after some brainstorming with the team here, was to experiment with a couple shot 4.0 blocks. Since they have the problem of cracking behind the cylinders anyway gouging out the cast cylinder for replacement seemed like a good start. The idea is to remove the cast cylinder from the block and replace it with T6 aluminum tube. Weld it to the bottom of the water jacket and the deck. Then bore it out to 4.1" for the Holland/Ford 3.9" flanged liner.

The liners are pretty inexpensive at about $30 ea. They are extra long to tune the overall length for longer bores. The aluminum tube is very inexpensive at $9 a foot. The materials total for those is at around $300. I spend about $600 on my Westwood liners shipped so we're ahead there. There will be some extra machining cost for the initial removal of the cast cylinders and then a final bore and press of the Holland sleeves. The extra step is obviously the first rough bore.

All in all it should actually cost a little less than my resleeve of the rover block for my current project at 5.0L. For those who know me personally, yes, I am going to finish that one first. There is some machining I can't do on my own and OK. I don't know how to weld aluminum so I guess I'm gonna learn. That will be fun and is really necessary for this project to be fiscally feasible.

So far I have the spare blocks at the machine shop for the initial overbore to remove the cast cylinder. I'll update the thread when I get the block back.

[BlownMGB-V8]

Nic, assuming you're going with the ubiquitous 60xx series tube, a tip on welding. Provide a generous fillet to fill when welding. Due to the alloying elements filler must be added to 60xx series alloys to avoid cracking of the weld. You can use either 5 or 4 series filler, 5 being the most common. Of course, the composition of the block material may take care of the problem, so if you can determine the percentage (in the block) of silicon and... what was the other element used that caused cracking? Well, you get the idea.

JB

[roverman]

Nic, As I recall, I had some welding done on a block,(corrosion repair) and it welded just like heads, very well. Weld area needs to be extremely clean, preferably, dedicated, rotary stainless wire wheel. I suggest 1-2  electric burners for preheat. Tig. with DC-negative and Helium will produce needed heat , with less amps and should be easier to manage. Probably  will need main caps out of the way and no cam bearings or plugs. I think I would start with a middle bore and alternate tranverse on remaining bores. You will probably need 300 Buick main bearings for align boring. No funny plating ? Thanks for "sharing"-unlike SOME. Good Luck Nic'....Art.

[roverman]

Nic, As I recall, I had some welding done on a block,(corrosion repair) and it welded just like heads, very well. Weld area needs to be extremely clean, preferably, dedicated, rotary stainless wire wheel. I suggest 1-2  electric burners for preheat. Tig. with DC-negative and Helium will produce needed heat , with less amps and should be easier to manage. Probably  will need main caps out of the way and no cam bearings or plugs. I think I would start with a middle bore and alternate tranverse on remaining bores. You will probably need 300 Buick main bearings for align boring. No funny plating ? Thanks for "sharing"-unlike SOME. Good Luck Nic'....Art.

[NixVegaGT]

Sweet! Thanks for the tips guys. So far I've got a buddy with a shop that will let me use his TIG. I'm a little concerned I won't be able to get the torch into the bottom of the bores. I guess I might have to go gas for those if I can't get the tip down there.

That will be a challenge. FUN.

[BlownMGB-V8]

Nic, there are a wide variety of tig torches available, some of which are made just for that type of application. You can start with a short back cap and if that isn't short enough look at the torches at the bottom of this page:
http://www.tectorch.com/wt%20water%20cooled%20torches.htm

JB

[NixVegaGT]

Great! I did contact a welder yesterday to talk over the project. Obviously the bottom of the bore is the challenge. We pretty much didn't even talk about the deck. I'm going to bring the block by when it is cut open to go over it again with him:

http://www.castmetalwelding.com/Automotive_Engine.html


Good guy. Really into the project concept. He never questioned why we were trying to do this and new a ton about engine building. Pretty cool.

[roverman]

I seem to be having trouble finding "source" for Loctite brd. of "sleeve retainer", anerobic bonding liquid for auto sleeves. Anybody ?  thanx, roverman.

[tr8todd]

This what you looking for?
http://www.amazon.com/Loctite-Sleeve-Retainer-Strength-37424/dp/B0002KKTIG

[roverman]

Todd, that's the stuff. $31. for 50 ml. Cheap insurance for "tractor sleeves". I think Stg II, alum. Buick heads will like the bigger bore. Thanks, roverman.