308 V12 conversion begins

Paul,
The end of the pan on the trans is on attached to anything that matters so it can wrap all it want and it won’t matter. The one rail on the other hand in a spot where welding would want to banana the whole trans just like I did to the block. Never weld more than you have to is a good rule I think. Charles did a great job jigging everything and it sounds like he got it all hot enough to do a full anneal in the jigs after welding and is appear to have worked out very well for him. I just prefer not to weld that much if I can avoid it.

I could make some jigs for the crank journals and the decks bolt everything down and sent the block out for anneal and probably jet it a bit straighter, but then it would be annealed and I don’t really want that. Ihave never had any luck trying to seal surfaces that spring into place like I would get bolting straight heads to a warped block. I think re-cutting is the way to go at this point.

It looks to me like the 330 heads will drop right on to the 400 block assuming the oil returns are in the same places, but an easy fix it they’re not….which is why an early block would not have made the TR head install any easier.

 

Pre and Post heat treatments are good no matter what metal you metal. The more pre-heat the closer the base metal is to the weld temp, so the less thermal expansion/contraction induced stresses there will be. Also the metal is much much weaker at high temperature so it will yield much more readily which also means lower final stresses.

Some metals like cast iron need to be hot-hot when you weld and cooled slowly or you get a pretty undesirable heat-treat conditions and often cracking. The biggest thing with aluminum is that is conducts so well you simply can’t get the weld zone hot enough to weld if the base part is not pre-heated.

In the case of my block, the best thing to do would be to send it out for re-hardening. That would get it hot enough to relieve any stresses and then get the base metal back up to original hardness. It still wouldn’t be prefect because the welding rod is not the same alloy as the base metal (welding with base metal alloy cranks every time unless you have the whole parts within 100-200F of the melting point) so there would still be stresses when it was done, but they would be somewhat lower and the base metal would be harder around the welds.

I’ve had really good luck with motorcycle cases and heads, brackets, and such doing them the way I did this engine. I’ll do the machining in a couple steps and that will let anything that is going to move do it now. I think it’s going to be just fine and I’m going to quit worrying and get on with getting it DONE!

 

Last night it was back to welding. I filled in the original oil return holes. Filed in the pin/oil feed hole that struck water-jacket and added lugs for what will be the new oil returns.
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I got a little machining done last night and I’m now thinking it’s going to be smooth sailing from here on in and time to start planning the next phase…adapting to the trans.

I can’t imagine that with all the oil problems the 308 has to begin with that making the pan longer is going to help any. That said, I guess it’s probably dry sump time. I’m thinking use the original pressure pump and add a 2 or 3 stage scavenging pump.

I came across a company that sells a roots style pump and I have hard time resisting anything the even sounds like a supercharger. Aside from that, it’s lighter, more compact and pulls a higher crankcase vacuum than standard gear pumps. I might have to have one of these....I better find out how much they cost before I make plans though.....


http://www.daileyengineering.com/oilpumpmain.htm
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Oil pumps are expensive....it looks like $715 for 2 stage, $1100 for 3, $1375 for 4

2 stage it will be I guess. They have them to spin in either direction so I can mount it along side the engine or sticking off the front.....hmmmI wonder what ebay has.....

 

Thanks Dave.....clearly this wasn't one of my better ideas

That is not a bad....I'll need to look into it.

 

I'm going as fast as I can, but it all takes time.

Here's what I did last night. I'm trying to finish up the one bank before I do the other side. I put the pin holes in that align the head and I mostly got the oil feed solved for this head I had to drill down in the corner of the head surface, then drill sideways through the end of the block without breaking out of the block or into the water-jacket on either hole and still get everything to intersect to form the oil passage. Now I feed to weld the hole shut where I drilled through the deck and the end of the block. I still don't have oil though because I couldn't intersect the original oil feed down in the block, I need 1 more cross-hole and I should strike oil. I'll drill that tonight……and this was the easy heads I think, on the other one the situation looks worse.

Tonight, after I hopefully strike oil, I’m going to new return holes into the lugs I welded on and carve out the water ports to match the heads. Then I pull it off the machine to do the welding, then back on the machine to clean the weld off the deck. Then on to the second head Saturday/Sunday I guess and hopefully start the timing cover Sunday/Monday. Hopefully by the time I get the timing cover sorted out, I think about 2 weeks) I'll have tracked down at least 1 348 cylinder so I can rough out the bore in the block. I'm hoping to be test fitting and on to the trans adapting over the holiday weekend.....it's a lot of work......
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Paul,
I try to never keep track off the time on projects like this....Lana might find it them I'd owe her double the car hours

I'm taking pictures at every set, so in theory if I wanted to do it again I would know what I did... I can't imagine ever wanting to though......

 

I think they make a machine for protoyping like a CNC with a mig gun that could do just that layer by layer....that would be pretty cool.

 

Stop by in a year or 2

 

On the TR heads, the center exhaust flanges are nearly touching each other so there isn't room to run anything between them. That's why I decided to use 2 further apart where the flanges do allow something to fit.

I though a lot about external lines and that would definitely be the easier approach. I decided to tough it out with internal lines though. I think once they are done they’ll be more robust and more OEM looking….I want to be able to tell people I’ve got the factory V12 option since all the parts I'm using were available in 84

I do like that idea. I thin the air cooled porsche and VW enginges had copper ring gaskets on the heads and about the right size bores. Now I wish I had the round 400 water ports back as orings sit much better in round groove. I guess I could buy cheap rule die and punch the right shape seals out od viton sheet material.......I need to give this a bit of thought.

 

I'm looking at the shape od the TR water ports and how thin the deck is and not seeing a good o-ring option...I'm pretty sure I could get a 1/16" o-ring to stay sit in the block with vacuum grease or something, but a small cross-section like that wants about .010" compression, which isn't much.

What popped into my head was permatex 518. I could o-ring the oil feed and copper ring the heads then 518 the water....maybe???? I've sealed all kinds of things with 518 over the years with excellent results.

Last night was a night of Lana said, so this morning I finish the drilling on the 1st oil feed and did in fact find an oil feed. Now I need to plug the 3 open ends of the holes. On to the oil retun holes.....while I continue to ponder the water o-ring/sealant issue.

 

I used it for all the sealing on my 2 blower set-ups and the last one was 22-23 psi, well above the water pressure. It's a pain to break loose and scrape off when stuff has to come apart, but I have never had it leak on anything I've tried it on....and it doesn't care a bit if there is a little cut-in at the edge of a weld or any other small surface defect that a gasket would hate.

I think 518 counts as an on-the-shelf gasket solution too. So that along with VW/Porsche copper rings and a couple o-rings and there would be no custom disposable parts on rebuild.