Archive for drivetrain

Terrible day

It can be so demoralizing to work on old cars, even worse working on Ferraris! After overhauling the engine on the blue 330 2+2 and addressing a bunch of other issues, we drove the car and experienced a major vibration that is present under high speed. Whether the car is coasting in neutral or in gear, anytime you go above 50 mph the feeling is there. We suspected that the original Ferrari driveshaft with the rubber flex joint was the problem even though everything looked good so I sent it to be balanced and checked for run-out. The vibration was still there so I checked the transmission and rear axle flanges for run-out, both of which were perfect so after experiencing problems with numerous Ferrari driveshafts, I opted to make adapters to convert the shaft to a Spicer-Hardy U-Joint style. Nate installed the new shaft and guess what, still a vibration (although much less). Could it be a bent pinion shaft or bent main shaft in the transmission?

I assembled a Ferrari 250 engine and got to the cam timing today only to realize that the valve height was not set correctly, so all apart again!

A car deal blew up in my face as well, only because of a minor miss-communication no less.. I could really have used that deal to keep my quota up to maintain my dealer license. It is so hard to broker car deals and so rewarding to sell something that either we own or have at the shop. When the car is gone, there is so little control.

What else…. We have a low mileage 512BBI all apart for a major service which is becoming a major engine bay clean up, not such a big deal but how does a legitimate low miles car look so ratty? It won’t take much, a little paint here and there will tidy up things immensely.

Here is a photo of the BBI engine out and apart to replace the lower timing belt drive pulleys as well as a major service which includes valve lash and new cam belts.

Oh yeah, the brake shoes that we sent to be re-lined for the Monza are way to thick and the newly re-sleeved drums don’t fit over them! Ahhh!

BBI belt service

BBI belt service

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One of my Favorite Conversions Solutions Revisions

We rarely have to repair rear axles and usually just clean and inspect the bearings and install new oil seals. Be it a Jaguar, Chevrolet or Alfa Romeo, it is rare that we see a ring and pinion that is damaged or bearings that are worn out. I hate to disturb the factory relationship between the ring and pinion gears so if the bearings check out ok, I keep the thing together.

Additionally, most car companies have figured out how to make the final drive robust and problem free because they are aware of the forces involved with the ring and pinion bevel gears – except for Ferrari. They used a deep groove ball bearing and sliding inner race roller bearing that cannot handle the axial loads on the pinion shaft. Other companies used tapered roller bearings that can handle a tremendous amount of this fore-and-aft thrust while spinning with ease but the Ferrari style comes apart and destroys the gears.

My solution is to replace the sliding inner race roller bearing and the deep groove ball bearing with a pair of tapered roller bearings. This photo is a 250 GT Lusso center section with the “chicklet” style limited slip differential. On some axles I’ve install tapered roller bearings to support the differential but on the later axles there isn’t much room to install this type of bearing and I have found the original ball bearing set up to be adequate. I have done this conversion to many cars that have gone many thousands of miles with no issues.

Final drive Ferrari

Final drive Ferrari

GT Ferrari 250 Axle Center section

GT Ferrari 250 Axle Center section

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Ferrari 250 Transmission

After overhauling dozens and dozens of Ferrari transmissions I have a good idea on what to expect when the case is opened up and shafts are broken down. Whether it’s a 250 GTE 4 speed, a 246 GT Dino trans-axle or a 330 GTC/Daytona style 5 speed trans-axle,  synchronisers on Ferrari’s do not last many miles however, the rest of the components are over built and hold up well.. The bearings and gears are over built and the machined parts like flanges and shafts are impeccably machined using incredibly hard steel. The transmissions have oil pumps that pressurize the main and lay shafts to keep everything thoroughly lubricated so the bearings that the gears turn on are flooded in a pillow of oil.

This transmission out of this 250 shifted well but had the typical severely worn synchronisers so I was prepared to perform the “normal” repair of cleaning, inspecting and replacing the end bearings and synchros. This trans had been run without oil for a long time and the bearings in the photo were so wiped out that there was about .020″ clearance between the gear and bearing where there should only be about .005″. How did this thing work at all?

250 GT transmission overhaul

250 GT transmission overhaul

Transmission overhaul bearings

Transmission overhaul bearings

Bearings Ferrari transmission

Bearings Ferrari transmission

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911 Porsche Transmission Buttoned Up

I got the transmission all buttoned up. It is in the car and I will get it on the road tomorrow AM. It shifts well from my little test on the lift, hope it feels as good on the road!

915, 911 transmission

915, 911 transmission

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915 transmission for Porsche 911

When I first drove this 1983 Porsche 911, I found the shifting to be difficult and it was grinding gears badly. My suggestion to the owner was to get in and replace the synchronizer bands before something breaks.

After taking it apart I couldn’t see much wrong and the synchros seemed used but not totally worn out. Like many other car manufacturers, the synchro for 2nd and 3rd gear is different than of the other gears and maybe someone put the incorrect part on the gears.

It wasn’t until re-assembly that I noticed that the dog teeth on first gear were chipped and remembered that the slider (operating sleeve, shift sleeve) for 1st gear has asymmetrical internal teeth to meet up with the corresponding dog teeth on 1st gear. The operating sleeve can be reversed  so the side that should engage 1st gear is incorrectly jamming into 2nd which makes engaging into either of these gears while under motion nearly impossible.

Lucky for the owner, I located a shop who can replace just the dog teeth (engagement teeth) for short money without having to spend the $2000 that Porsche quoted to get the parts. We sent 2nd gear  from a 901 transmission to the same guy for repair and cannot wait to see how they look and more importantly how they perform.

Transmission repair Porsche 911, 915, 901

Transmission repair Porsche 911, 915, 901

901, 915, G60 transmission for Porsche repair

901, 915, G60 transmission for Porsche repair

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Ferrari 330 GT 2+2 transmission

Still looking for someone to explain to us why Ferrari went from the compact light weight and wonderful shifting transmissions in the early 166/195/212/225 cars to enormous and heavy cast iron transmissions on the later 250/330/365’s. Here are photos of the 330 2+2 5-speed and a 166 5 speed. There is about 100 lbs difference in weight and a considerable size difference. Did Ferrari use some truck or tractor transmission for these later cars?

The blue 330 GT 2+2 that came in earlier this year ended up needing an engine overhaul but I was fortunate to be able to drive the car prior to breaking it down. The transmission shifted perfectly but on acceleration/deceleration the shift lever moved back and forth significantly. As some may remember, this same thing happened to a 330 GTC transmission a few years ago and it turned out to be a loose ring nut on the main shaft.

I was certain that we had the same issue on this 330 2+2 and when I took off the top cover, it was instantly obvious that the ring nuts at the back of the main shaft holding the gear cluster on were totally backed off. They are doubled up to jamb together to prevent loosening plus there is a locking tab for extra protection on backing off… but still, someone managed to mess this up. Thankfully no damage was done to the internals.

Huge Ferrari transmission

Huge Ferrari transmission

Early Ferrari 5 speed aluminum transmission

Early Ferrari 5 speed aluminum transmission

loose ring nuts on a Ferrari transmission

loose ring nuts on a Ferrari transmission

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Ferrari GTE transmission 250

Here are some more photos of the GTE transmission that I am overhauling. Everything else looks fine inside, we are replacing all of the bearings and synchroinzer bands. The main shaft and lay shaft gears are all in excellent condition.

Transmission

Transmission

Gears for mainshaft and layshaft

Gears for mainshaft and layshaft

but the gears and spacers are all good.

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Porsche 356 SC engine

This SC engine is super healthy, great running and has outstanding compression but it also has many little leaks it is filthy. We have done a huge amount of work on the body which constituted completely restoring the car so we are getting the mechanical work done while the car is being block sanded and painted. I have said it before and will say it again, these are the best engines, light, powerful, simple and parts are available anywhere.

I just ordered ever  body rubber seal, full front suspension overhaul kit, assorted specialized trim screws… boxes and boxes of stuff to make this car as new and the order was under $3000.  Incredible what you can buy and how inexpensive the parts are compared to Ferraris and other cars that we typically work on.

The flywheel was sent off to be under-cut and the carburetors are getting the royal treatment from Karl.

SC Porsche Coupe

SC Porsche Coupe

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Reproducing Ferrari water pipes in Stainless Steel

Here are photos of our jig to re-make a common sized water pipe on a Ferrari 250. We have been making flanges at the water jet shop and have a bunch of the large bell flanges that adapt the 1″ tubing to the larger thermostat housing.

This 304 stainless steel is great stuff, very workable, machinable, weldable.

To see the ones that came off the car click http://www.ferraricraft.com/2009/12/corroded-ferrari-water-pipes/

Fixture to reproduce water pipe

Fixture to reproduce water pipe

Reproduction water pipe in stainless steel

Reproduction water pipe in stainless steel

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KNOCK IT OFF – WHEEL GOING NUTS

091116_rpmvt_knockoff_1052Alright, all puns aside, the number of different variations of wheel nuts at RPM is astounding. Here are some examples and some more interesting facts about them. Firstly, Ferrari wheels employ singular nuts to fasten each wheel to each axle or hub. So, in your road car, you have generally 4 or 5 lug bolts or lug nuts that hold each wheel on – trucks have more. Ferraris more than any other make, use large racing style wheel nuts, quite similar to those in use on racetracks all over the world, even here in the US in Nascar. Many other Italian cars and some English cars used this method of fastening as well.

The big difference between the wheel nuts on current race cars and on vintage Ferraris? The method of removal. The current race cars use a large diameter socket, while the vintage cars have 2 or 3 ears extending off the nut. The method of removal is repeated smashing of these tabs by the standard equipment lead hammer found in every Ferrari – it isn’t just for fending off would-be attackers. The lead hammer packs a punch, and the softness of the lead won’t mar the finish of the nuts, just watch out for your fenders on the back swing. At RPM wheels are removed frequenly enough to destroy these hammers, so we have a mold to recast the hammer head.

On to the nuts themselves. The word “smontare” seems to be on nearly every nut. » Continue reading “KNOCK IT OFF – WHEEL GOING NUTS”

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