Ive heard that the diff in the 1980 was not as strong as other years is this true ?

 

well, the diff in your '80 is a dana44. the earlier cars used a dana36. you would think that the 44 would be stronger than the 36 but this isn't necessarily true. the 44 used in '80-'82 cars was unique to these three years, so it's harder to find critical parts, mainly the housing. speaking of which, it's aluminum. it's also a very different design from the 44s used in the c4 cars. not only is the housing different but it doesn't use the same ring and pinion either. where it has an advantage over the earlier 36s is primarily yoke size, specifically in the '80 and '81 4-speed cars and all '82s. they used a 3" yoke versus the automatic cars 2.5" yoke. someone will have to confirm this but if memory serves me, some of the SBC 36s used a 2" yoke, while the the HiPo and BBC 36s had 2.5 yokes. they weigh less because they're aluminum but that can be a disadvantage with extreme horsepower applications. the other really good news is although they're very unique in the corvette world, they use the same dana ring & pinion as some bronco and jeep stuff so you can actually replace the R&P in your dana44 for less (and more commone) than the iron 36 or either c4 36 or 44. all in all, they're actually a good, reliable unit for most driving conditions. for extreme power, a later c4 dana44 would withstand more and a *shiver* solid axle more yet. if you have one and it needs to be rebuilt, i cannot stress the importance of having a compotent shop do the work. i have photos of the results of having a half-a$$ed shop do the work.

 

I had mine rebuilt about eight years ago and sprung for 3.70 gears while I was at it. My 406 tips 500hp and I have yet to hurt the rear end.I imagine a set of slicks would change all that though.

 

The Money Pit:
The guy who swapped my 2.87s for 3.73s in '03 has over 30 years of hot-rod (11-second street car), drag-car (10-second drag-car), and C2/C3 (several BBC Corvettes) experience:
he STRONGLY-ADVISED against running even the softest street-tire in my '82, even with a stock Cross-Fire, saying it is the weaskest rear-end assembly he's seen.....

 

Money Pit - if you drag race what kind of 60 foot times are you getting? With new tires, 3.73 gears, and a well prepped track I am getting very close to sub 2 second 60 foot times (2.02) on my '81 on street tires. Im thrilled and nervous at the same time.
I don't launch at high RPM, maybe at 1,500 RPM with very little spin.
Is a 60 foot time a good estimate of the "not to exceed" time in terms of the dana44 strenght or is it that initial launch (i.e. - high RPM launches and sticky tires) that will damage the differential?

 

Maybe EDDIEJ82 can offer some ideas on this topic:
his C3 runs mid-7s in the 1/8-mile (I believe), but how his rear-end survives is beyond me.....

 

The shop that rebuilt a 3.08 Dana 44 (out of an '80) said it should handle at least 400 hp. The 2.87 that was originally in my '81 withstood 348 hp/379 ft.lb. and the 3.08 is holding up ok. The original BW T-10 didn't.

 

I will find out shortly how much a Dana 44 can handle I just finished my TKO 600 install and just about ready to let er rip

 

I have yet to run on a track with my 80,but can tell you the traction,even with 295-50's is non existant. If I hit the throttle hard below 25 mph,all I get is smoking tires through 1st,and 2nd.I'm sure a set of slicks would give me a wheelie once or twice,and a popped rear end.
I'm more into handling now anyway,so slicks are not an option,in fact the next cam will bleed off more low end(with the Vic Jr) in hopes I can hit the throttle harder off the line,and not spin the tires,but have more rpms through the gears to play with.

 

This may be a bit off-topic, but I've run the Victor Jr., and the 327/365 HP intake on my Z28 at the strip, and I've found no-difference in ET or MPH between the 2 intakes:
even the 60' and 660' ET/MPH are with-in a few hundredths of each other (depending-upon weather, track preparation, etc.)

Maybe the converter (8"/4500 RPM stall), gearing (4.10s with 2.75 1st gear in the THM400), and slicks (28" x 10" ) make the single-plane/dual-plane argument a moot-point in my particular application?

 

I'm sure they can be built to withstand around 400 horse. You have to understand that the original diff's are 23-25 years old and should at least be rebuilt and u-joints changed to solid spicer. You should be alright then. I wouldn't try and pound out 500+HP on these units. Ask Van Steel about your options on beefing up one of these rears. Dan would be more than willing to help considering he himself owns an '80.

Les