Unless my eyes are deceiving me, it appears the UP steam department has added Porta's Lempor exhaust nozzles (or a similar design) and a corresponding lengthened petticoat pipe.

see:
http://www.railpictures.net/viewphoto.p ... 014&nseq=0

Any updates or commentary on the engineering, design, and installation?

I think I see someone has chalked a phrase on the interior of the firebox door...and it ends with 'Porta.' Nice touch.

KL

I see something about Porta is written on the smokebox door. Look at the last line of the writing.

I was talking to Mr. Lee about this last year. Hewas interested with the improved performance the GCR has seen with their lempors. What a better way to provide for a real world test...the GCR is real world but the UP operates at high speeds and...on an articulated engine! Can't wait to see the results of this marvel of Porta, Day, UP, and Wasatch engineering coupled with the improvements to the net open area in the firepan.

Are you sure that photo was taken in Cheyenne, Wyoming, and not Aguascalientes, Neuvo Leon? ;<) The writing is in Spanish and looks to me like it roughly translates "if you have nothing to make, don't come and make it here - Porta."

.

Ok, I knew from the outside that 3985 had two stacks and see from this photo it has two exhausts. Did all articulated have two exhausts? Or did they some combine the exhausts into a single stack?

Thanks,

Bob

She has two sets of cylinders.

D&H and Clinchfield 4-6-6-4s had single stacks. N&W's Class A also had a single stack. There are many more examples of 4-cylinder simple articulated having this arrangement.

UP did some testing with double and even triple stacks in the late 40's and early 50's. IIRC, UP used this to improve drafting and decrease back pressure. The double exhaust nozzle and stacks is an excellent starting point for a Lempour conversion.

This appears to be the handy work of Nigel Day. I wonder if he has ever dealt with two stacks/two petti-coats before. I know that one lempor gives improved draft, I wonder if that improvement was figured on two stacks. I am sure that it was. Interesting but the proof will be in the running.

The translation is given in the caption on page 20 of Locomotive & Railway Preservation Issue 63 (Jan-Feb '97.)

It is interesting to note that when the Clinchfield bought the UP design challengers from war operator Rio Grande they did not perform well on eastern coal and in the drag service required on parts of the Clinchfield. As part of the changes made to the challengers Clinchfield changed the engines to single stacks. This coupled with the addition of syphons and larger air openings in the grates improved the performance of the engines and they were said to perform well after the modifications. Since Alco built the UP design engines as well as the Clinchfields own challengers I suspect they assisted in the design changes to these engines and possibly supplied parts. If records survive of any of this it would surely be interesting reading.

John Bohon

Interesting to note that SP used a 4 cyl, single exhaust in their "Cab Forward" design. Go to the bottom of the page.



http://www.uprr.com/aboutup/photos/steam_freight.shtml

Thanks for the answers. Other recent Lempor conversions we've seen have also included changes in the size and shape of the stacks (at least I think that's the case). Can anyone comment if the petticoat pipe is to avoid exterior changes to 3985?

Bob