308 V12 conversion begins

I moved the engine around a bit and did some measuring last night and it looked good. There is no question the engine will fit in the engine bay with either the stock head or the TR heads. For the stock heads to be used, to be used the early carb cam covers and a custom intake would be required, that will be the fall back plan if the TR head retro fit runs into a brick wall for some reason.

My next plan for the night was to pull the heads off, which was much easier said than done. Those suckers are stuck! It looks like there will be a 1 to 2 day delay while I build some kind of puller to rip them off before I get to see what I'm up against with the TR heads.

 

I'm still working on getting the freakin heads off the block I started building a puller set-up tonight, I'll post some pics if I get something that works.

I thought this was picture worthy though. This was a brand new engine stand, but the engine has drooped to about a 15 degree angle with all my banging around trying to get the heads loose. I guess "they just don't make them like they used to" applies here.
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Tuning is a good thing no doubt. I'm not sure yet what I'll be able to do for length, I want to get the head on the engine before I try to layout the intake. I may be able to cross the runners and get a little more length. The desing of the air box on top can contribute significantly too, it's call the helmolz resonance.....more to think about.

http://en.wikipedia.org/wiki/Helmholtz_resonator

 

It was all straight before I started trying to be the heads off. I will definitely do something else before I start putting anything back together.

 

I like it!

 

OK, the stuck heads have been dealt with, so back to the regularly scheduled programming. I posted that adventure in the 400 section if anyone is interested.

http://www.ferrarichat.com/forum/showthread.php?p=137233239#post137233239

Now, it turns out the TR heads are a perfect fit on the 400 block except for the heads studs, the oil feed, the oil returns, the cam drive and possible some of the water passages……I need to do a little thinking to decide just how pig-headed I’m prepared to be with these heads.

The top row os studs is right. The end studs look like a 1mm mis-fit, but that I could fix by opening up the holes in the heads, I’m sure there is enough metal to not have any problem.

The real problem is the bottom row of studs is off 2mm by the look of it. There isn’t an extra 2mm in the head to move the holes I don’t think and I’m not willing to try and find out. There is material in the block, so I could plug the existing holes and punch a new hole where I want it. The other option the comes to mind is to make 1mm eccentric studs then open the holes in the head 1mm. That would solve the problem with the end studs too, but eccentric studs would need to be positioned in the correct orientation them pinned or set-screwed to keep them there.

I need to finish the disassembly on the block and see if the pressure oil feeds are fixable with major problems….it might be as simple as re-drilling and plugging the old holes.

I need to think about this
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....at least 1

Down sizing is not a good idea generally. It MIGHT be possible to find something to match the strength, but it would almost certainly not be possible to match the elasticity. Steel, regardless of the alloy or hardness has a modulus of elasticity of 30 Mpsi. A bolt can be thought of as a very stiff spring, using a smaller diameter means less cross-sectional area and that essentially means you’ve installed a much softer spring to hold the head down. If the tensile strength is high enough, you could generate an equal clamping force cold or hot, but not both because you have a much softer spring.

Upon reflection I think the best of the bad options is to plug the holes to about ¼” –3/8” of the deck with threaded aluminum plugs, then weld the last bit solid so they can’t ever turn. Then simply re-drill the holes in the correct position and re-install the OEM studs. So that’s the plan provided I can find a solution to the pressure oil feed location problem.

The timing chain problem looks like the solution is to do a little welding on the end of the TR head and machine it to look like a 400 head. The 400 timing sprockets look like they need a new center welded in to match the TR cams, but there might be room for a simple adapter….eventually something has to be easy….right????

 

I drilled and tapped the aluminum pluller plates. The Puller plates bolt to the top of the head using the cam and cam cover studs, then the new studs thread down and hit the tops of the head studs in the block. You crank on the puller studs and it pushes the pushes the head studs out of the head and the head pops right off.

 

I didn't have a big plate to use laying around and buying 1 is expensive....then I got thinking about it and figured for this application a single big plate really wasn't any stronger than a series of small plates which were easier to make and handle any way. Odds were there was no need to hit all the studs so I just made 3 to start with and on the 400 head, by going every other stud pair there was a common bolt pattern on both heads so 3 identical plates is all that was needed. It worked out good, there were 4 or 5 corroded studs on both heads but they popped right off.

On my QV, once I got the heads off (not smart enough back then to make a puller), I opened up the holes about .030" so they can never ever stick again. and just to be sure I put a little permatex aviation sealer around the base of the studs to keep water out and never-sieze on the studs. 7 years later when I torn it down they fell right off. I'll most likely take the same approach with this engine.

 

The drains are even easier to run external lines for, that's no problem at all. Drill and tap the head and pan and clamp a fuel hose on. I'm going to see what can be done for internal lines for both first becasue it just look neater, but it will be what it will be I guess.

 

Not knowing any better back then, I got the QV heads off by driving wedges in. The first head took 7 hours with a 3 lb hammer, and it's a good thing I started with that one because the second took 11 hours. best I could tell the engine had been overheated a few times before I got it which made the heads gaskets weep a bit into the stud holes....it was a horrible job and I was absolutely dreading the V12 with even more studs to be stuck. The puller made short work of it though and it only took a couple hours to make the plates….well worth the time.

 

I don't know that they would fit on the block either....I don't know what all changed. The Goldsmith book is incorrect about the DOHC heads not fitting. The DOHC heads will fit in the 308 engine bay without much drama and will make a proven 400 hp, maybe more, so there would be no advantage I can see to the SOHC heads at this point really.

I'm going to tuff it out a bit longer with making the TR fits work.....I really don't want to need to put a blower back on to get back to where I was for hp and I really don't want to have to take the QV badge off the back of the car

Since I have to do some work on the block now anyway, I'm thinking I may cut the flange off the back and fix it to a 308 configuration and use the 308 flywheel and starter. I think it will look neater that way but I need to do a little more measuring to see if that work buys me what I'm thinking it will. My thought is a short hydraulic throw-out bearing and a little work on the flywheel and I'll save at least an inch, maybe a full 2 inches off the assembly length. That would make life good again in spite of this project needing a lot more welding than I was hoping it would.

 

That ans I'm more than a little OCD at times

I think the issue with the studs will cause about a 2-week delay, not really a big deal in the scheme of things I guess…..more scary to see than actual problem.