308 V12 conversion begins

Where's you sense of adventure man!

 

Yeah. If you dig up into there the valve guides will have less support and less heat sink. How about running smaller diameter steel guides with off-the-shelf bronze sleeves?

 

It can move about 11 or maybe 12 degrees it looks like
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Ya know Mark...

In reading this entire thread, I have a question for you.

Wouldn't it have been EASIER or made more sense for you to just cast your own engine block, heads, and transmission case to suit your needs? LOL You are absolutely my hero. I do not know anyone who would ever put this much work into something, but you are a man who sets his mind on a goal and does anything to accomplish it.

I bow before you good sir!!

Brian

 

I was thinking about the same thing a bit. I'm moving the valves 2 mm apart which means the guide OD has to go up 2mm. The bigger OD has more contact area with the head so even though I weaken things a bit moving the port, I'm thinking it ends up about a wash in the end. Maybe.

Thinking back I'm pretty sure part of the way I convinced myself to use the TR heads was because I didn't want to screw around moving the ports in the 400i heads the pointed all in the wrong direction to get good flow. Damn project creep.

 

I just realized the flaw in the plan though. There is no problem top and bottom, but if I break into the water jacket on the sides there is a bit of problem. There are 3 thinks that need to be separated, air, water, oil. With the tub in the port idea and only welding inside the port I can only separate 2 or them and would need to rely on the stock head for the 3rd seal.

Breaking into the oil galley is no problem because there is no place for the oil to go. I'm not going to be anywhere near the water on the bottom so that's no problem. But the water on the sides is a problem. If I cut through the sides them I need to put a beam of weld on the outside of the tube to seal the head to the tube to keep the oil and water separated. It could in theory be done in the oil galley, but it means welding under the cam saddles and the bucket supports….very very tight. Bad idea.

The only practical way to raise the port is a 2 piece insert. It could be either a bottom fill plug and a new roof that are welder in leaving the sides alone or a tube with the top cut out that is weld in first to seal the water/oil, then the roof added to seal the oil/air. Either way it can be welded completely from inside the port, but it has to be 2 pieces.

 

Thanks.....but what I am is an idiot.

 

...........you are a glutton for punishment!.. There is a 12 step program for Obsessive Compulsive Disorder but you first have to admit YOU HAVE A PROBLEM!

 

I guess someone else had the same idea!!


http://acme-ltd.com/Ferrari/Article/index.html

 

Mark- I love this thread. On the exhaust, why not make 304 SS tips and then have them chromed? Will make for a really long lasting set of tips. If you need generic SS components, Borla has a very good reputation for long lasting components. Their catalog:

http://www.borla.com/media/borla_catalog_46.pdf

Taz
Terry Phillips

 

similar, but he did it the much easier way

I have a copy of his book.

 

I'm an idiot with a serious case of ocd, no question.



I'm through step 1

 

Borla has a lot of nice stuff.

I've never seen SS chromed don't think....i wonder if it can be done???

 

I think this started out looking for 600 HP, its worked its way up to 800. Somehow I hear a blower in this motors future. You know, you could run turbos off the front bank and only need two outlet pipes instead of headers. Run normal headers off the back bank, it would sound a bit strange but still awesome, and you would have boost. Using your fancy dyno program, what would 8 psi boost do to it??? Save you all that work re-routing the ports.

 

8 psi is about 50% more hp, so if I say I only get 700 out o fthe engine, then add 8 psi it would be at about 1050-1100.

This one's not getting boost though, plus it's too late on the not moving the ports idea

I was at about 146 cfm after I got the flow bench recalibrated and pretty well sync'd to my buddy's. It's now at 152 with a pretty rough clay roof in the port. The valve job should add about 5 so with some clean up on the roof I'm at 160. If put comes to shove I can to up to 33mm vavles, but I think I'll get it with the 32s...the guides are pretty porky too for the valve stem size I'm using, fixing that should help too.

I don't get to fill the bottom lthe way I was thinking....I'd forgotten just how undersize the port entrance was. It's about right now and I'm about s high as I want to go I think. The side view picture I was working with doesn't tell the whole story....I need a width and I'm scared I'll hit water if I go any wider.
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Thought about buying/borrowing an ultrasonic thickness tester?

 

I've never even heard of such a thing. I need to spend some quality google time it sounds like.

 

Raise the floor of the floor of the port. High cfm port flow numbers, huge ports, do not always equate increase HP, unless you like peaky power or decreased power.

 

There's a company called Krautkramer Branson that has these. We used them at an aerospace co I worked at.

 

I agree with what you're saying about flow v hp, but I'm not sure it exactly applies here.

I know it looks big, but this is a very high velocity port and much smaller than is often used at my flow rates. The 160 cfm at 10" H2O number I'm looking for is the minimum number required to fill my 458cc cylinders at 8500 rpm. The stock head was good for 98 cfm if I recall so I need 63% more air. My port entrance is about 50% bigger than stock but my valve seat area is only 25% bigger than stock, so the air entering my cylinders is moving 30% faster than in the stock head.

The stock ports are really buggered. The flow area at the manifold flange is only about 80% of the area of the valve seats so the ports is a diffuser and simply incapable of high velocity flow they way Ferrari made it. The performance is pretty good at moderate velocities, but the port becomes extremely inefficient as velocity increases.

Most modern ports are designed like nozzles with a taper toward the valve and that is what I have. The port has a 4 degree included angle from the seats out and that dictates the port diameter at the manifold flange. These are exactly the port dimensions I've been using in my simulations

The 308 QV/328 heads are very much like the TR heads in design and I have some actual data on the QV heads. On the 348 ferrari used the same head casting as the QV, but opened the port up basically as much as they could similar to what I did on the first go at the port and made more hp everywhere. This is basically also what was done with Russ's 328 heads and his engine is anything but peaky. This port design works and makes as much or more hp at every rpm than the port design used on the stock QV/TR heads does. I've got a 360 head sitting in the basement, I'll measure that port to see where I am in comparison….it's got big tapered ports though from memory.

All that said, if I raise and round the port floor a touch I might be back to where I can use the Suzuki TBs. I'm at a 46mm port exit and the TBs are 46mm throttle plate with a 44mm head side ID. If I bore them out 2mm (commonly done on the suzukis) and mount them right down on the head instead of up high where I was thinking before they might work. I need to look at them again and maybe play with some clay to see shape might work.

The Suzuki is another port size data point too. The top of the port is 44mm to match the TB. It is a 325cc cylinder that makes 45 hp/cyl at 9800 rpm. I've got a 458cc cylinder at 8500 rpm that I'm planning to get 65hp out of. So I need 22% more air based on proportional dist x rpm or 45% more air based on hp. My port is 46 v 44, so my port is 9% bigger flow area making it 10% smaller proportionately than the suzuki's and I'm trying to flow 22% to 45% more air through it, that is a lot of velocity I think they use 33mm intake valves vs my 32mm to, so I have way way more velocity into the cylinder and this says my port and valves are too small if anything.

 

I'm still not understanding how you're not up into the 300 cfm range on your ports. I'm not a Ferrari guy by trade, but I am a Ford guy. We were getting over 320 cfm on the intake of the 4.6 DOHC Cobra heads for the 03-04 Cobras that we ported and ran on our Superflow 600 flowbench. I don't understand how you're not at least there if not MUCH more. But then again, I may be bashed for being a Ford guy. LOL

Had to ask the question,

Brian

 

No bashing from me.

All my flow numbers are at 10" H2O. Most US car guys quote numbers at 28" these days, so my 160 is your 275. The 160 (275 at 28") number is the target because that is just all the air an engine my size can use at 8500 rpm. Remember my cylinders are oversize but still only 458cc each vs a 4.6 v8 that would be 575cc per cylinder, so per CC I have much more flow.


Also, that 4.6 engine uses 1.75" intake valves to get 300 cfm if I'm not mistaken. I'm using 1.26" valves and getting 275 or almost double the flow velocity which yields a much higher volumetric efficiency number. I'm using very small ports and valves for the size/rpm of the engine. The average US engine has a VE about 85% and the hopped up engines around 95%. My engine will be about 110-115% VE due to the high port velocities. That is the same as adding about 5 psi of boost to an engine with an 85% VE, not too bad.

 

I've had stainless bumpers chromed. It's apparently a little more difficult but not impossible. I really think polished stainless looks as good as chrome. The only reason I had to chrome the bumpers is because someone in the past had made a weld repair right in the center and the weld bead, even though perfectly smooth and blended in, had a different color. The weld was slightly yellow and chroming made that disappear.

 

Mark, Wil- They even chrome plastic, and probably your bathroom fixtures are chrome plated brass. Good chrome shop can plate just about anything. Corrosion problems probably zero on chrome-plated SS.

Taz
Terry Phillips

 

The "chrome" on plastic is actually aluminum vapor which applied electrostatically in a vacuum chamber. It has nothing to do with electro plating. There ARE issues with chrome plating stainless but they can be worked around.