Range Whip Sting VS. later Sting pipes?

[80whip440]

Any difference between the 77 Range Whip Sing 440 pipe and a later 80 Sting pipe?
Have a 77 pipe that I was thinking of putting into my 80 Whip. (both 440 Cuyuna motors)
Sting pipe is a bit tight on the right side, afraid it's going to melt the hood guide on that side.
I've always heard the Sting has a better flowing pipe, but should it be the from a later sled?
Should it have the insulation and tin cover, or better left plain?
Already sanded down and painted a nice gloss black...

[80sting440]

I removed the heat shield on my 80 Sting pipe before using header wrap. The shield was only to protect the plastic intake tube, which I no longer use. 

Rene      

[weverat]

I always thought the Range Whip, Sting, and TK used the same pipe, but I did notice 2 different part numbers in the parts book?

So I really do not know, they seam to fit and mount up the same, but they could have some internal differences. Only OBJ and Roger know!

To make these pipes fit onto a standard whip, you also need the exhaust manifold, and then they use the same mounts, and fit right in there.

I am starting to think the 79 and 80 TK pipes were the best, and maybe a tad different then the Sting, and Range Whip. On the other hand, Scorpion probably used the same pipe on everything, again, only OBJ and Roger know!

Think about this, some of the TK,s were rated at 48hp, and the latest ones at 52hp. Did they actually use a dyno, or just change the number?

[weverat]

Scorp Pipes

Concerning the 1977 to 1980, Range Whip, Sting, and TK Pipes

I researched my parts book and came up with 7 different part numbers, but in some cases the difference may have been just the mounting brackets, I do not know

First of all, I believe the Range Whips were all 400, s? And used their own pipe # 020104

77 Sting 440 48hp @ 7500 Pipe # 020295

78 Tk 440 rated 48hp @ 7500, and the 78 Sting 440 rated 52hp @ 7500 used the same pipe
Here is the confusing part, the parts book lists # 021231 or 021507 check with factory, and then it says can also use # 020295 which is a 77 Sting pipe.

79 Tk 440 is now rated 53hp @ 7800, and the Sting 440 is 52hp @ 7800 and use the same pipe # 021507

Ok here comes 1980 and 2 more pipe numbers.
Tk 440 now back down to 48hp @ 7800 using part # 021687.
Sting 440 also back to 48hp @ 7800 using pipe part # 021768

The good news is all these sleds used the same exhaust manifold # 020296

I have never tried to actually identify these pipes, and the only one I have for comparison is the original pipe that came on my 1980 Sting. The rest of my Sting/Tk pipes came from swap meets, so who knows.

Just imagine Scorpion building these sleds, my bet is a Tk or Sting could leave the factory with any of these pipes on it, and nobody would recognize the difference.

I have a hunch the 79 Tk and Sting pipe # 021507 may have a header section about an inch or two shorter.


All these pipes work well and are a huge performance upgrade from the Whip muffler

[obj1]

wow! if those Merc guys find out we only have 48 little bitty horse powers they will be mad all over again!

[weverat]

OBJ, Do you think all those pipes were the same, or was there some with different dimensions, and how can you tell them apart?

[obj1]

80whip440... as far as i know, the 77 range whip sting has the basic same pipe. The angle right at the flange is a little different cuz the belly pan and hood bracket is real tight in that area. Also, as model years changed there were small changes to mounting brackets, pipe wrap and some were "dented" to clear recoil and some were not. These little changes would be the reasons for the different part #'s. But.... the same basic pipe will still push a Exciter or Twister right through it!!

[80whip440]

Tightest spots I have are right at the hood guide and underneath at the right spindle. 77 Sting pipe has a mount that comes off the right side of the hood hinge bracket, the Whip has one underneath off the crossmember at the bottom of the pan. Had to make a connector for the rear as the Sting has a bit of a different tab. We'll make it work, I 'm pretty sure.
If left unwrapped, do you think I could melt the pan?? It's minty with no cracks, would like to keep it that way...

[80whip440]

Fudged it around again tonight. Not gonna happen to my liking. Angle to the manifold not quite right no matter which way I support it, and it hits on the hood guide. and leaks out one side. Guess I'll have to fix the R/W Sting instead and put it where it belongs...

[speedbuff]

hey weverat do you think the 79 whip tk really is 52 hp ? where did you get that info and what would the difference be between 79 and 80-81 ? they strike me as being identical ?

[weverat]

No, they were probably 45 to 50 hp, and I can not find any difference between the 78, 79, 80, 81 TK pipes, and engines.

My numbers come from a old Powerbloc clutch manual. They have a calibration section where list weights and springs, they also list hp and rpm. Who knows where they came up with this info.

[speedbuff]

I would be very interested in a copy of that I have a powerbloc that I was trying to dail in on a 1980 tk 440 .Any chance of scanning it and sending me a copy?

[weverat]

If you click on them they get bigger, maybe try printing. This is a pretty cool old book, it lists a lot of sleds, gives hp, rpm, and suggested clutch calibration.

I do have one Powerbloc clutch on an old Bubble nose with a Sachs 340ss single, and it seems to work ok. They certainly are easy to adjust, just add or delete those washers to adjust the weight. It helps to have a couple different springs to try.

Also they come apart real easy in order to shim for different belt widths

They still make these clutches, but I can not imagine buying a new one as they cost over $400. Guy,s like us get 2 or 3 complete sleds for that price.

Dam, I love junk!

[speedbuff]

Thank you so much hope I can enlarge them and print them!!!!

[speedbuff]

I was thinking that one reason the 79 tk has a higher hp is because the pipe came wrapped from the factory dyno's show when a pipe is physically hot it produces more power maybe the wrap keeps the heat in

[weverat]

Possibly, but I still think Scorpion just used a bigger number to help sell sleds.

Or maybe they used a thicker base gasket effectively raising the exhaust port, and then clutched it to run at 7800, and at that rpm it showed 52hp on there dyno.

I have tried to modify the 6 bolt Cuyuna 440, and have had very limited success.

The old 4 Bolt engines do seam to respond to some mild porting, even with a Donaldson muffler.

It would be fun to add a Sting pipe to the old 4 bolt 440, and raise the exhaust port about 3mm, maybe grind out a bit wider two. I am guessing it might out run the modern Cuyuna? Which would be huge, as the old 440,s were only about 40hp.

[mooreperformance]

When I attended the Scorpion service school back in the day they claimed the difference in power between the Whip and Sting was the pipe. I guess everybody knows that. Later I had a chance to cut open both pipes and inspect them. No difference. I believe the Whip pipe from the exhaust port to the end (overall length) was longer producing more torque and the Sting pipe was shorter producing more horsepower. Any two-into-one (single) pipe on a two stroke twin is just a megaphone exhaust (not tuned with a reverse cone and stinger). No real tuning (with reverse pulses)is possible with a "Y" pipe.
Just my two cents worth.
As far as horsepower? I think that the Mikuni equipped engines made more power but only measurable on the dyno. Maybe one or two more HP.
I have always wondered how much power a 440 6-bolt would make with a good dual expansion chamber exhaust. Anyone know?
Dennis Moore

[weverat]

I thought we had a picture of the innards of a Whip pipe on here some where. The one I cut open was different then a Sting/TK.

Yes, it is amazing that the two into one manifold system works as well as it does. I have twin pipes on a 440 JLO, but have failed to make it work as well as it should.

There are a couple twin pipe Scorps at the grass drags around here, but they are really not all that fast, and they will not out run the D Class Stock TK's. Back me on this OBJ.

With a bunch of dyno time,a hacksaw, and a welder, I bet those Cuyunas with twin pipes would really come to life!

[weverat]

Here is a Whip pipe, I do not know what the TK pipes look like on the inside as OBJ will not let me cut one up

[80sting440]

Thanks for the demo weve.

Rene