What are you 5 speed guys doing for launch? I need 3 feet or something to build boost on the line.

 

Any help for a guy like me with 2wd? Besides slicks? My best so far has been a 12.97@106.4mph w/2.10 60 ft. I know I have much room for improvement. Just don't know how to get there.

 

are you guys launching in 4lo or 4hi and at what speed can you shift out of it

 

yea i almost stalled launching last week (1st time) i had a lousy 17 something but 92 mph! beat a 68 nova ss! in speed

 

use 4hi and shift out after it shifts to 2nd or 3rd.

 

streetsmoker what kind of air pressure are you running in the rear? You might need to try dropping it down to around 30 psi for the track.

 

Those of you asking about launching a manual.....well I have one and I don't know anyone launching with any boost. Only thing I've heard is bang the rpm's agains the rev limiter and drop the clutch with a cadence so it is not too violent. Better have a good clutch though.

Only other thing I've discussed is a line lock for your brakes. I've thought about it, but going to wait for a little bit. I'm getting a new double disk soon....it is ordered. That should help with the higher revs and dropping the clutch. I personally launch in 2nd and know a guy running 12's in a 3rd gen nitrous truck that launches in 2nd. I may try a 3rd gear launch after I get the new clutch. The only other time I tried that, I almost stalled it out on the line..... ....I've been chicken "bleep" to try it again.

 

Ive tried that but im running a single sps66 and mach 6's , with that slow of spool up ur just not going to get a good time i guess!
Hahaha!
Its pretty funny to watch tho!

 

When I street/drag racie with my 3.54's and the open diff, its hard to get a good launch without frying my tire. When I launch, I'll dump it in 1st, then as soon as it gets rolling I hit 2nd and mash it. It'll lose traction but just wait for it to redline and then grab 3rd and so on. Thats how I gotta do it for now with my stock clutch. Seems to work pretty well though.
Anyone know how much a locker is for a Dana 80 with 3.54's?

 

Somewhat less than $700. The problem is, if your housing has those "case saver" shims outboard of the stock carrier, the detroit locker is too wide to fit back in, even using a case spreader. (the detroit locker replaces the carrier entirely) You then have two choices-turn the locker on a lathe and machine the ends so it's a little narrower, or machine down the case saver shims. If you just omit the shims entirely, you could just put a huge stack of adjustment shims inboard of the carrier bearings. Problem with that is, it'll take a ton of them, and having that many shims would probably make it very hard to get the bearing preload accurately set, since the big stacks would always want to compress just a little more as time goes on.

In my case, we machined the case saver shims down. They were 193 thousandths each when we started. We took about 40 off of one, and about 60 off the other. It just so happened that we got it PERFECT-we didn't have to use any adjustment shims at all! I could never do that again in a million years.

A detroit locker for a dana 80 is simply a detroit locker for a 70 HD with the ring gear bolt holes drilled out bigger, since the 80 uses bigger ring gear bolts. So far as function, it works fine. It adds some play to the driveline, but it's not that much. Mine is well-mannered on the street, and does not clank or clunk like you often hear they do. I have abused it at the track several times, as well as doing 4 wheel burnouts across intersections. It has never complained during any of this.

 

Yeh I've done the lower pressure thing. Got those times with 25lb. in the rear tires. Still can't get on it till tranny shifts to 2nd though. It feels if I can drop to say 1.8 or so 60ft. times with slicks and line lock I would be knocking on the door of low 12's high 11's.