308 V12 conversion begins

If you guys haven't seen, I'm getting ready to run off some board to let you run 1 MAP/TB on an ITB set-up. This will yield a good strong MAP signal to make the tuning at low power and idle quite a bit better than you would get just using the TPS signal.

If anybody else needs one, let me know.


http://www.ferrarichat.com/forum/showthread.php?t=175114

 

Head #2 was coming along nicely...until little one snuck up and stuck a welding rod into the motor of my little grinder and fried the speed controller. Now its off/on and that is no good as it's really hard to control the tools at full speed inside a port. Hopefully the $11.00 switch thing fixes it and I don’t need to buy the whole pedal assembly. I’ll see what I can do with my other grinders in the mean time I guess.

 

Now if only I had a feon sniffer........


I'm going to try soap and water. I'm sure I can tape everything well enough to get a a few psi and then look for bubbles.

 

It's a catch 22 though...if he's not in the shop I need to be up stairs watching him, if he is in the shop I can work but he losses and breaks stuff. I found my valve seta cutter today.

I'm going to start thinking about the intake manifold while the grinder is down rather than screw around with the much slower small grinder.

I took a quick look at the TBs.....they look as bad sitting on my head as they did on Daves'. Turning them 90 degrees makes it look not so bad....but I'd rather they went the normal way eeven it it turns out to be more work. I think with a little re-work on the shafts and a little milling on the TB housing everything will be just fine.

 

I looked at the manifold a bit this morning. The temp one I made for flow testing is beyond ugly but it puts everything in the right place and has plenty of metal so I could grind the inside anyway I wanted.....did I mention it's ugly?

I need to think a bit about what to do for the final design. The TBs have a big flange on the bottom that is used to secure the air box. The TBs were held on the ducati by popping the snout into a rubber boot. I’m thinking being able to adjust the length somehow would be good but the stacks hold the injectors …and I don’t have a lot of room.

Right now I’m thinking about cutting nothing cutting off most of the snout and fitting it with an o-ring to seal it in the manifold and a flange on top to bolt the TB to which could also secure the air box. Maybe.
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The majic fix for the one in the picture is going in the trash

Yes it's very thick so I could grind as I pleased. The new ones will be 3/16 or 1/4" wall tubing with a flange welded on top to mount the TBs.

Optimum distance and placement is application dependant. 100mm sounds about right for a low rpm application where the common thinking is to get the injector as close to the valve as practical. As RPM goes up the injector needs to move further back. By 8000 right below the throttle plate is better and above 10k above the throttle plate is best as a general rule.

On my engine right below the throttle plate is a problem space wise and is part of the reason I will be using 2 injectors per cylinder with a small injector mount close to the valve and a larger injector mounted above the throttle plate.

 

I got some cool stuff today. The new valve springs and Ti retains. Aren't they the cutest things?

They are a touch longer than the stock springs, but install at 1.400, vs the stock springs at 1.5/1.4 outer/inner so I gain .100" of room. They come out almost exactly the same same seat pressure as stock but about 10# lower than stock full open but that's ok because everthing is SOOOO much lighter than stock. These retainers hold tiny little 9.5mm dia shims that come 1.2mm-3.5mm thick so again WAY lighter than stock and can't come flip out. I need to get the lower spring seats form the suzuki dealer I guess.
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I started pulling on 1 last night and it had no interest in coming out, but at least 1 set of my TBs has the TPS removed. It sounds like I'll need force all but 2 out.

Have you ever had a good look at the balance tabs that are used on the Japanese motorcycle TBs? It takes very little space and could be made to take as little as 1/8" by letting the adjuster live pushed in and over the TB shaft bushing I think.

 

I still need to weight the valves…but I don’t have the ones I settled on yet and when they come I’ll need to finish machine the stems to length. They are SS, the stems are 5mm the faces are dimpled and the back angle is different which I think will combine for a net weight savings over the stock even though the heads are 5mm larger.

The big weight savings in the shims. The smaller and thinner 9.5mm shims should weight only about 6% what the stock 31mm shims weight on average. After that come the retainers and keeps…I’ll weight those tonight but I expect to see about ½ of stock. Then the springs look to be about ½ of stock weight (I guess we count ½ the spring weight in the calcs because one end move and the other doesn’t).

 

You’re still way ahead or me. I just kind of looked at it the other day but I’m still thinking about getting the heads done. My thought was that I’d try to make all the TBs about the same but that might be a bad thought.

I do think a center actuation is possible but would need to be a cable system with the cable going around the outside of the TB to TB linkage stuff……I’m not sure I like cables for this though because it means keep the front and rear cable adjusted to match. I’m leaning toward something like the stock ducati stuff on one end to drive the bank of 6. I need to look at in and give it more thought though.

I’m going to need to do something custom with the rear deck lid I think….I’m not sure what yet though. I would love a 10lb FG or CF deck lid to make putting it on and off easier as well as to pull 40 lbs of the top of the car. My vague plan was to add some form to my stock lid to make a mold. Have you got a link to the one on ebay?

 

Another boy……I guess that means I’ll need another Ferrari….you know…..just so there is no fighting

 

Thanks.

I really need to get this stupid engine put together sooner rather than later. I don’t care so much about the rest of the car because the projects are all relatively small, but getting the engine/trans wrapped up is not small…..

 

Dave got me curious so I took a few minutes this morning to actually take a good look at the TB situation.
The first thing I notices is that both TBs are actually the same casting, but 1 has the TPS mount removed creating the shortest of the 4 shaft bearing surfaces, about 6.5mm shorter than the opposite side, which is then asked to handle a probably the largest load due to the length the shaft sticks out. This tells me all the bearing surfaces can be as short or shorter than what is currently the shortest without much worry.

Setting the TBs side by side as shown gives a spacing of just under 106mm…..I need 94. Notice though that the way I have the castings sitting the sides that are touching both has bosses that are about 6.5mm longer than the shortest boss and can therefore be shortened 6.5mm each giving me my 94mm spacing with a full mm to spare. I think I’ll be fine on the spacing issue but it’s tight.

Last I’m still a little confuses about the best way to handle IAC (Idle Air Control). I got looking at the high idle cam Ducati uses…..and I’m thinking I may keep or something very similar it and connect some kind or linear actuator to it for idle air control. My first thought was a standard IAC controller mount to some kind of small plenum that fed all the cylinders below the throttle plates……but I think I would need to put 1 way check valves in all the lines for that to work right and that is a lot of part that can go bad. I’ll have to give this more thought.
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You've got to get up pretty early to stay ahead of me

no, I have a little window in the morning between when Lana leaves and little one wakes up that I can get ot the shop then I upload everything while I eat breakfast.