The Elephant In The Room: unloading the load from a B-body.

[fullmetaljacket]

I fab'd a lighter 3pc steel bellhousing for the car, bare bell is 16.3 lbs. Bell with steel block plate, steel mid plate and bolts is 26.2lbs. Made it 3pc so I could pull either the engine or transmission without need for any added support.
For comparison, McLeod aluminum bell with titanium liner (no block plate) is listed as 14.81lbs.

Here it is tacked together before welding...

Here's the finished product...

Just a fun street car, no need for a sfi cert.

Also fab'd a lighter sheet metal tailhousing to replace my Toploader's stock cast iron tail. Got the transmission's weight down to 91.4lbs including oil and a slip yoke...

The '71 Charger sitting in the driveway will be getting a similar treatment, plan is a vintage dirt track style build for the street with radiused wheelwells and wide-5 hubs.

Grant

That there is some serious Fabbing.

 

[dvw]

So basically what this boils down to is that you can get away with an 8 3/4" instead of a Dana because of the clutch slip. All else being equal that's 100lbs. Perhaps that would also translate to smaller U joints and yokes too. Not sure if there is anything else to consider.

Don't know how much traditional clutch linkage weighs but I'd bet a hydraulic throwout bearing setup could be lighter as well - no clutch fork, rods, Z bar or pivot. The master cylinder for those setups is usually aluminum and the reservoir is plastic.

If you run a blow proof bell those things are ridiculously heavy so any weight savings could potentially be erased just by having one of those on board.

A Dana is not 100lbs heavier. 50lbs at most with a sure grip. Wthh a spool the difference is even closer. Not to mention that a Dana has a more efficient pinion height. Most anyone I've ever seen that has done back to back tests has not slowed going to a Dana. When making a part light it's only has to be strong enough not to break. The issue is how many times it will last.
Doug

 

[fullmetaljacket]

A Dana is not 100lbs heavier. 50lbs at most with a sure grip. Wthh a spool the difference is even closer. Not to mention that a Dana has a more efficient pinion height. Most anyone I've ever seen that has done back to back tests has not slowed going to a Dana. When making a part light it's only has to be strong enough not to break. The issue is how many times it will last.
Doug

This is why even though it doesn't see much racing at all anymore, a multi-point check list is followed religiously most often to make sure that critical parts are still sitting strong. As far as a Dana, I'm confident with it behind there. The 8-3/4 most likely would have lived back there being that the car is an automatic and light, but a Dana was light on my nerves.

 

[dvw]

My 11.0@3885 lbs (ya I know it needs a diet) street car (that has numerous passes) has never broke anything with a 8 3/4. The lighter quicker 9.0/9.25@3350-3600lbs) racecar is on it's 4th set of Dana gears.
Doug

 

[Dodge 330]

Anyone know the diameter and wall thickness of the steel tubing for the alternator bracket on a BB? I'm at work today and was going to make a run to the supply house to see if they had something similar in Aluminum.

 

[dvw]

Anyone know the diameter and wall thickness of the steel tubing for the alternator bracket on a BB? I'm at work today and was going to make a run to the supply house to see if they had something similar in Aluminum.

You need clearance for a 3/8" bolt. Wall thickness? How brave are you? I would say .125" in aluminum. Maybe .090" but that might crush when tightened. Fully story on tubing. Years ago I crewed On Koffels B/D comp car. it was a 5 speed Liberty. The driver who was good at the tree was struggling with it. We set the air gap tighter before every run to try and help. Finnally I measured the air gap after he hit the clutch pedal in the pits 10 times. Air gap was huge. The connection between the pedal and the bell crank at the throw out arm? Light weight tubing. It was stretching with every pedal press.
Doug

 

[fullmetaljacket]

You need clearance for a 3/8" bolt. Wall thickness? How brave are you? I would say .125" in aluminum. Maybe .090" but that might crush when tightened. Fully story on tubing. Years ago I crewed On Koffels B/D comp car. it was a 5 speed Liberty. The driver who was good at the tree was struggling with it. We set the air gap tighter before every run to try and help. Finnally I measured the air gap after he hit the clutch pedal in the pits 10 times. Air gap was huge. The connection between the pedal and the bell crank at the throw out arm? Light weight tubing. It was stretching with every pedal press.
Doug

Yeah, certain stresses can crush, bend and collapse lightweight tubing or flat stock if not considering it to have enough meat for strength.
I’m traveling at the moment, so I couldn’t give you the measurements on my aluminum tubing/ spacers between the alternator and the motor head, but I do know that it is enough thickness to not crush and it definitely is light.
I would just copy the thickness of what you already have which should be sufficiently thick and it will still be light.