308 V12 conversion begins

Couldn't you take your straight tubing to a local exhaust shop or tooling shop and have them bent to spec?

 

Couldn't you take your straight tubing to a local exhaust shop or tooling shop and have them bent to spec?

 

The first one is about done and it didn't turn out too bad....it looks a whole lot better than the thing I welded up for flow testing. 11 to go.
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mostly in line, they are offest about 1 connecting rod width.

 

I don't know...maybe. It would still need to be made oval and tapered wheich would mean some cutting and welding. This isn't too bad......

 

Awesome , better make another one for the other head because I'm keen to see the clearance between the two TB front to back ! It's going to look sweet with 12 TB down the middle !!

 

Not with that wall thickness.

I have a source for thinner stuff though... I've got a few of their products in my garage. Will measure.

http://www.intercoolerparts.nl/index.php?page=categories&group=21

 

Hey, I COULD switch to Dutch for my postings if you'd prefer that?

 

Neat - is that going to be bent a little more though? I looks like if you had two opposing pieces like that they might not leave each other enough room in the middle.

I don't think that'd make much difference to me for the technical aspects of the posts - I understand so little of it anyway. I just sorta hang on for more pictures, the simple explanations, and the pictures.

Really looking forward to seeing the engine started in the car.

All the best,
Andrew.

 

That does look really nice Mark. Did you "V" groove at each weld and did you weld on the inside seams? Looks like most, if not all of the grinding was done with burrs. Correct?

I just might have to use this technique on my intake runners.

Tom...

 

I V'd it nearly all the way though, it took 3 passes with the welder to fill it up. That made the inside weld basically just a fuse job with very little fill needed...so only the torch needed to need be down inside. I used the new wp-24 torch, it fit and worked perfectly.

I ground the inside with a burr, I'll need to match it up to the head and TB so its not done yet, just roughed in. The outside I did with a disc grinder then a quick sand with a small drum sander.....it's still a little more wavy than I would like but it was getting late last night and I didn't feel like messing with it anymore. I think I spent just under 2 hours total on it and about 1/2 of that was thinking time. The rest should be under an hour each....I hope.

I'll take some pics of the steps on the next one.....they are pretty ugly after the crushing and V grooving but it all works out. I think the finished wall will be in tha 1/8 - 3/16 everywhere so that's good too.

 

Yeah, I can get that stuff but I can't weld it to the heads.....it would be a puddle long before the metal ont he head started to flow. Also something thin doesn't give me much freedom for re-shaping, witht eh heavy wall I just need to get the formed shape close and then grind to finish shape.

 

Thanks for the info.

1/8 to 3/16 should be plenty strong.

Are you going to get this one on the flow bench today?

Tom...

 

I'm keen to see the clearance too...of lack there of. I'm going to mill most of the ears off flush to the base flange and set it up so the base flanges basically touch.....I think.

I don't know if you noticed but the air for the idle screw comes in a hole drilled in the side of the TB becasue the TB is designed to sit inside the air box. I'm thinking I'll do what ducati did and put them in the air box.....but you can't see them that way.....I need to think about that.

 

I'm going to put a rib of some kind on too I think, just to be sure.

I don't see any need. The inside is the same shape as the big ugly one I did the flow work on and because the maniflod is tapered and everything is pretty straight it helps the flow, it works like a big velocity stack. I'll get them all made and welded on then I'll be ready for the finish flow work

 

If the top of the air box comes off easily for show-off time then the TBs might look pretty dramatic all nestled in the box. With the top off the viewer could get a good look at the injectors too. I think.

 

I've thought about making the top of the box part of the deck lid so it's off any time the hood is open.....it could be clear too, but I suspect it wouldn't stay clean very long.

I need to think fast about what to make the air box from. If the bottom of the box gets trapped between the TBs and the manifold I need to know the thickness to get the clearances right.

Another thought I had was that the air box should look similar to the QV plenum with the ribs, a ferrari logo and QV in the corner......all stock

It's getting to the point where all the little things need to be decided and that's a good thing. I talked to a local machine shop..... thet can't do the heads but may be able to do the balancing (a lot of metal needs to come off the crank becasue of the Ti rods and its better to turn it in a lathe rather than drill a bunch of holes) and cylinder honing, I need to stop back in a few days.


I think I'm going to tell people the it is an early limited proiduction GTO(I have a GTO front). Ferrai designed and tested with a V12 then decided to go V8 turbo and a little more agressive body. Very rare..but that pretty much requires I do a fairly stock looking air box if I expect anyone to believe me for more than a second look.

 

I got the parts for the other 11 cut and milled. I'll start doing some cushing oval and welding tomorrow. 4 1/2 hours so far.
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I would have cast these for you Mark If Id had seen what you wanted in time, but It looks like you have it almost there. Looking good, in every way as always.

Brian.G

 

Yeah!!! LOL!

 

This morning I gound the V into the slit parts, pressed the slit closed (I finish closing them in the vise if required), welded them up. 1:15 bringing the total to 5:45. You'll see how close I was with my 11 hour guess.

Tomorrow or mybe tonight I'll make them into ovals.
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A casting is what this wants to be for sure! It’ll be done the hard way in a more couple days though I think

 

The more I think about it the more I’m leaning strongly toward a QV plenum resembling air box. It would be over twice as long and a bit wider……so it would need a horse in the center think to look right.

I’m also thinking I may lose the ducati velocity stacks and make the tops of the stack part of the bottom of the air box. This would let me use 12 simple tubes between the air box and the TBs which would make changing the runner lengths pretty quick and easy. The down side is I’ll also need to build the injector mounts into the airbox and do something (maybe) about the idel air holes in the sides of the TBs making a little more work but I think it will look right for an ’84….so it could be a GTO prototype.



Oh…..maybe it’s a GTO-Si, very rare. I’ve never even seen it mentioned in a book before. I think you had to custom order them

 

+1 for the nifty horse in the center

 

I didn't see a type stamp on this tubing. 6061 T6 I presume. If so, are you heating them to kill the heat treat so they bend and squish easier? What wall is this; 1/4"?

Tom...