F40 LM Restoration

Tim, you've become a real "Ferrarichat Superstar!" Really glad you didn't give up on this thread. We all know you are a true die-hard fan. Please publish a book with pictures when you're done! Thank you for sharing your experience with all of us who wish to be able to do this sort of thing someday.

The car is going to be amazing, and your patience is admirable though honestly it's moving much faster than I thought it would. Great shop you have to work with, and it's really cool you were able to work directly with Michelotto.

Please keep this going. One more here that is calling this Thread of the Year!

 

Tim,

What wheel and tyre size will you be running?

 

I think you mean 30 series on the rear. 35 is preferred but not available in what you're looking for.

 

I agree as I would like 35 series for the rear as well. Let me know what you find over there but over here, I have come up empty on all brands, including Pirelli.

 

Why aren't the BFG's street legal in the UK, they have more of a tread pattern than the Toyo's?
I guess Hoosier Street radials are also illegal.
Since 75% of the time the car will be on the track, as I suggested another set of rims with street tires and the main wheels for the race setup.
As far as the tyre compliance issue that we discussed earlier, previous pictures of the car showed full on Goodyear slicks and 3-piece wheels, so the car had been subjected to the loading of full slicks previously.
Given you are replacing the full suspension with the Michelotti parts I would go with full race tyres as anything else is a compromise.
With respect, if it were my car I wouldn't chance a tyre with the sidewall construction like the BFG's. Too dodgy compared to a proper racing tyre.
Again a race wet tyre would have tread and softer compound so big traction or an inter that would last longer in dry conditions.
I would concentrate on that 75% track time as that is what this car is being built for.
On the street is ok but risky with a car like this, ultimately your decision.
Using original Pirelli P-Zero's would be a mistake as that is very old tyre technology.
Fascinating thread and we are all living vicariously through your masterful rebuild.
This is the ultimate progression for an F40, it deserves the LM/GTE treatment.
It will be an awesome car.
GV27TIFOSI

 

T,
Just sent you an email with a solution.

 

250 pf..... ????????????????

 

Tim

Its a technical quirk, which I have confirmed by the dept of transport, this could help with your tyre choice.

I plan to make my F3000 single seater street legal here in GB. As you can imagine 13" roads tyres of F1 size just dont exist. Avon however make a hard compound race rain tyre thats ideal.

It is illegal for a tyre manufacturer to sell tyres for use on uk roads unless they are e marked.

It is however not illegal to use non e marked tyres on UK roads.

As long as a tyre on a road vehicle has the correct tread depth and width as specified in the dept of transport manuals then it is totally legal to be used, even if they are pure race tyres. The warning on the side about not for highway use is just a disclaimer from the manufacturer

A car equipped with such will pass an mot test no problem.

You would just need to import the US spec road tyres from outside of the EU.

When previously used, non EU cars are imported into the UK they dont have to have the tyres changed, and when rally cars travel between stages on normal roads they are still fitted with non road spec rally tyres, all perfectly legal and above board.

Hope that might help

 

Almost looks like it's from a 625

 

Shweet and the bead on those welds are....... "making me frisky, honey".

 

I just emailed you some specs from a different book but I am looking through my workshop manual and I have one page in Italian that alludes to the liner specs someplace else. Can you see that in your workshop manual? It's in section B on an unmarked page.

Also, I do have a to-scale technical drawing of the motor's internals but there are no measurements directly listed so that's not helping...

 

It's a long shot but I sent a pic of the page to your email.

 

If you are referring to liner wear, I know it is specified to measure the liners at 3 different depths at altering angles in the liner. the measured figures cannot be more than .0005 inch out from one another. Just be advised the cylinders 2,3 and 6,7 do change shapes slightly under torque from the heads meaning measuring them statically should afford up to .0007 variation rather than .0005 as with the others. The Nikasil coating used on these liners is remarkably strong and was done very well from new so I wouldn't expect a large amount of wear.

The pistons, if scuffed on the skirt at all should be discarded. Piston to wall clearance should be not more than .0035 for this engine as I believe forged alloy pistons with lower silicon content are the material Ferrari use for F40s. If not then I can name an excellent source to have pistons made to OEM spec yet with superior grade aluminum. These are designed by a gentleman who was probably forgotten more Ferrari piston designs than any 3 people have ever done. PM me for info if you would like. Mahle I believe still currently make a set which obviously works well too.

 

Late note with numbers:

Correct bore size as new should be exactly 3.2283. If the bore measurements taken at 3 depths in the liner are greater than 3.2288 than I would replace the liner.

 

He knows. Ask him to send you pics of what he's built.

 

Happy to help, just make sure the liner is not hourglassed in the more central to upper liner area where the piston thrusts against the wall hardest as that is typically where wear is seen if there is any. Nikasil is very hard stuff, but it can be stripped and reapplied if worst come to worst. Nikasil plating is about .002-.003 on these things.