3.4L project

I thought I would lift the veil on this new project of mine. Most recall I rebuilt my engine about a year ago and it ran very well and for all purposes was pretty much a stock motor except for the pistons which were higher compression. I got the itch (much like Sean does!) to do something radical and push the envelope a bit in the interest of having a really neat 308.

So, what I have planned is using a crankshaft from a 360 and expand the bore to 83mm which puts me a hair over 3.4L. A 360 crank is a bit longer on the damper end and I am still researching the flywheel bolt pattern but none of these are big issues. The cams will be something with over .400 lift and in the area of 245 duration @ .050. Some have noticed the 36-1 wheel I recently installed as some sort of computer controlled ignition curve is to be required for this project. What I have no decided on is whether to stick with carbs or go nuts and inject it. I have heard the ITB setup is a bit of a bear and there is constant noodling.

Below are pics of the first batch of new parts. There are 44mm valves made by Manley which are 2mm larger than stock. Note the undercut is very flat as well. The tulip shaped stock valve next to it does not help flow with these heads. My heads are currently at a very trusted machine shop and are installing slightly larger OD and ID intake valve seats and then they will be ported. I suspect the intake bowl at the intake seat will have about a .020 shoulder which will obviously need to be smoothed and blended into the bowl for this port. Regardless, the flow should be much better than stock.
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Yup. I put 2-3k miles on it but just wasn't completely happy.

 

ZING

 

yes, that subject has been reviewed many a times. The issue is the oil pump location and the sandwich plate not quite matching up. A very large spacer and about a half a million hours of professional machining and engineer needs to take place to make it work.

 

I have no desire going with a stock plenum style manifold for this one. If I inject it, it will be with ITBs of some sort. The issue is the runner length which is just too short for these things. So if the ITBs I am able to get on the thing are still a compromise, with not just stick with carbs which are already a compromise and work fine?

You and Newman are incredibly persistent in your own ways lol.

 

Yes, just like that. Newman recommended I go that route

 

As I was researching the Ferrari bolt pattern, I came to think about the flat washer positioned between the flywheel and crank of a 308 (PN 103876). The further I researched this I found that this identical washer is used on just about every manual transmission Ferrari since the Dino. In essence, this means the crankshaft bolt pattern is identical amongst models. Although if I had to guess, I believe the 360 crank pilot bearing shaft is of a different diameter meaning I may need to modify the flywheel ID a bit. We will see

 

as in, the ID is fine and it fits?

 

Great work by Dave snapping some pics of the two cranks side by side. 308 next to 360. The bolt pattern is identical as is the pilot shaft. The flywheel may need a small spacer to meet the starter depth but that has yet to be determined.



Regarding the pistons. I will essentially need to move the pin 4.5mm to accomodate for the extra 9mm stroke if I were to keep stock quench (which is terrible). In the interest of increasing quench efficiency I will have the pin moved 3mm which allows the piston approx .040-.045 (1mm+-) clearance between the flat portion to the head and pokes the piston out of the hole .010 (.25mm). The quench on these motors is quite terrible in stock form being about .105 (2.67mm). I'm hoping the compression ratio I require at 83mm bore gives me a somewhat flat top piston. I sort of hate domes
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Agreed. The bolt pattern on every Ferrari has been the same since the 246 Dino.