FrankenFerrari - V12 Ferrari 308

Pete. (l33t FS) said:

In reply to mke :

That is a beautiful torque curve!

Starts high... and keeps pulling stronger, enticing more more MORE REVS

I'll share this because I found it amusing in a scary way.  I made a spread sheet that takes the estimated torque curve from the simulation and calculates wheel torque in each gear.  The idea is to calculate that best shift point in each rpm because as rpm climbs above the torque peak the torque drops and shifting to a higher gear the get back closer to the peak puts more torque to the wheels.   The very general rule is you shift at hp peak and land back at the torque peak.  But I ran the simulation out to 11k and the lines still don't cross so the correct shift point in every gear is redline....and increasing recline makes the car faster, which only encourages bad behavior 

I made a more useful version of the shift graph with mph on the x instead of rpm and it doesn't look AS bad.  I kind of don't want to rev above about 9500 so here what that looks like, the way to read it is when 1 line ends, drop straight down and that it where the next gear begins and the gap is to wheel torque lost in the shift.  I think the traction limit is in the 2000-2500 range somewhere, so 1st gear is worthless and  just open the throttle at literally any rpm in 2nd gear and the tire will spin as seen in a video I posted last year.   The tires spin in 3rd shifting at 6500, I haven't tried 4th.  I guess a 1/4 mile run would be 2, 3, 4 or maybe just 3, 4 with a 3000-3500 clutch drop.   Also note that with the higher redline (9500vs 7700) and revised drop gear ratio the new 240mph tp speed at redline in 5th, scary fast. 

If I let it actually go to 11 like the tach says it looks like this

Then a stockish 308 reving to 8000 would look like this.  The line cross at about 7500, so that is the right time to shift, the highest line is the fastest line at any given mph.  So the engine was matched nicely to the transmission ratios before I got involved.

Actually work.  The old gear adapter was a bit damaged and all my ring nut wrench did was bend 

So, since I'm only saving a small bit of the existing adapter I cut the nut and gear off.

Then I thought I ordered SS foil that was a lot more like shim stock, but I wrapped the top and bottom and heated it up to pull out the hardness so I can machine it.  

I went out to the shop to get started on the lower drop gear and realized my plan was just impossible to execute. I had it in my head I could cut the adapted to a 35mm OD but 42 is about it so its never going to fit through a 35mmID bearing.

I did slice it in 1/2 to make the machining easier so at least there was some progress.

New plan. I'm using angular contact bearing to handle the thrust loads, that means I can make the drop gear, is shaft and inside bearing an assembly so it is removed as an assembly leaving a 72mm hole behind it to put the trans adapter on/off through.

Just as a refresher since its been about a year, this is the general idea, trans adapter on the right, drop gear assembly on the left.the left end of the shaft is shown smallish but it will get enlarged as much as practical then a bearing adapter fitted over it to make it with with the same 35mm ID bearing the inboard side is getting.

This is just amazing work.

Thank you for sharing with us!

An attempt to redeem myself for posting the 308 kit project with 

(Actual) race car project for sale

In reply to mke :

Stored since 2001.....Still good deal for 35k

I've spent most of the day looking at parts and not liking ideas. The 35mm bearings came today and just now I ordered a 40mm ID bearing because my ne plan is a 1 piece (2 if you count the outer bearing adapter) shaft that just slips on to the end of the trans shaft instead of the 2 piece that bolted on and was making my life hard because I couldn't convince myself there was enough metal there to left me cut splines/dogs of adequate strength.  Now its a non-issue as is the need to find QV drop gears.  I will need to modify the drop gear case to fit the larger bearing which is a bother but doesn't look horrible.  I'm a little torn what to make the shaft from, 4340 or 9310.   I'm leaning toward 4340 and heat treating to RC50-52.

TurnerX19 said:

In reply to mke :

Stored since 2001.....Still good deal for 35k

yes, if the engine was stored properly and doesn't have rusted bores of valve seats.  Also Theiler, the guy who did the engine,  did some odd things and that's coming from me  so its hard to know for sure what's in there.  I just helped another 308 owner with a Theiler build blower motor re-time his cams to get it to run good.  The exhaust cam timing numbers were so far from normal I thought it has skipped a tooth on the belt, but no, that was were they were set and the simulator agreed that is were it made the most HP.   It was however just undriveable below 5k rpm and the power brakes didn't work at all.  I gave the guy the next best HP setting for the cams (108/108) from the sim and he reported it was a whole new car, well mannered and he didn't mis the 6hp or whatever it was.   So the engine is a wildcard IMO.

I wonder too if the cage is still legal?  

I like the way the fenders are done and would actually like mine the same I thing, but I suck at bodywork so the body will likely remain stock on my car.

mke said:

  I'm leaning toward 4340 and heat treating to RC50-52.

Decision made, 4340 ordered

Today was filled with delays.  Started cleaning up the bellhousing, off to the store for more spray cleaner.  Need to pull the bearing, off to the store for a new puller which need some modification to the arms to engage and I had to make a piece to lock it at the OD I needed.

Then dig out my notes from when I worked on gears last time....not very good notes it turns out so I remeasured 

Then cut out the old bearing boss

and cut out part of the bellhousing so I can get in to weld a new boss in place.

Tomorrow I need to make boss and get it welded.  I found some metal I think is left over from way back when I had a blower and needed pulleys to adjust the boost.

Wow

TurboFource said:

Wow

I agree 100%

Yeah, there's  a reason I didn't want to have to upside the bearing...but it seemed like time to just get on with it.

My favorite saying:

If you can't get out of it.. get into it. 

This doesn't even seem real anymore. Incredible. 

Yeah my "wow" and "astonished" and "bow" emojis are just... all used up. Behold, the field in which I grow all my superlatives! Lo, it hath been harvested, and all the bounty hath been bequeathed to this, the greatest build thread on the interwebs!

Srsly mke, you've recalibrated what I've thought to be "possible or impossible" and I've known guys who got to hang out with guys like Bruce "I have a forge in my garage at my house" Crower...

I have a system.  Find the bit that won't let me do what I want to do and remove it. Wash, rinse, repeat until the frikin think runs.

This morning I made the new boss  I was worried that chuck of metal was not long enough but I had at least 1/16" to spare. yay.

Then start setting up to weld remember I'd been nursing the argon tank and its empty empty.  Off to the welding store.  Then lunch, then finish replanting a hedge row that "we" decided would look better 10" closer to the walkway, then time to weld.  I like to preheat bigger stuff

Then...why no arc?.....oh....

Ok, I'll use the other torch (wp-24).  It will probably make welding the indie easier anyway

.....not sure why I believed it was 250A troch, clearly its not.

I got the top mostly welded before it blew. The replacement for the bigger torch (wp-20) will be here Saturday.  

The steel for the shaft arrived.  I've already broke enough stuff for 1 day so I'll maybe get going on the shaft tomorrow, although I don't think I have the nut to measure so I can't finish the design on that end and I'm honestly don't have much more than a vague concept of how I'm going to cut the internal spline on the other end....I guess I'll play with that next.

That inner spline looks like an EDM job to me. If you don't have reasonable and rapid access PM me. I have a neighbor with two running Soddicks, and about a week backlog.

In reply to TurnerX19 :

I do not have EDM access so was planning/plotting to try and broach it. 

Does this forum have PMs? My email is 

Mark@gemellocattivo.com

mke said:

Does this forum have PMs?

yes.  click on the username at the top of a post:

and it opens a profile summary for that user:

there's a "contact" button you click and it sends an email to that user's registered email.

 it will be from "robot@grassrootsmotorsports.com" but it will say who sent it.

In reply to AngryCorvair (Forum Supporter) :

I never noticed that, thanks. 

Now to anyone who tries to send me one, I don't get emails from the forum.  Some filter somewhere decided they are bad.  I checked my spam setting, added it to my contacts but I haven't had a threat update email or anything else from the forum for a couple years now so email me directly if you want to hear back.

The basic thought for internal splines at the moment is  my lathe is old and doesn't cut all that straight and square splines us the ID for alignment so it kind of has to be right making the lowest risk option to cut it a reamer...I found 1 for $85 at msdiscounttool.com

Then the splines themselves are 6mm and no real precision needed on the cut depth so I think I can just order a 6mm broach for $50

Then the broach needs a bushing to hold it in the hole, it normally looks like this

But I don't see any reason I can't add 5 more locating/indexing slots to cut the pattern I need.  I've seen people broach a pattern by setting up on a rotary table but that seems harder and riskier than an indexing bushing.   

The bigger issue is its not a through hole so the normal press the broach though, shim, repeat until the desired cut depth is achieved won't work.  I can make the hole in the shaft 3/4 or maybe an inch deeper ( and I planned to anyway so I can call it a light weight race part) but the plan would need to be cut all 6 then cut the end off the broach and repeat so it would be scrap at the end of the job.

I will hold ordering until I hear something about the EDM guy but I'm pretty sure I can do it the hard way for not a lot of money

This would be an easy job on a shaper and I am very much in the lookout for an Eberhardt or Gould&Eberhardt shaper if anyone knows of one.

mke said:

The bigger issue is its not a through hole so the normal press the broach though, shim, repeat until the desired cut depth is achieved won't work.

could you make it a through hole, then close the opening after you're done broaching?  sorry, i got a little bit lost as to what part is getting the internal splines.