I don't know the muffler (here's a pic below in case someone else does). It is totally open inside - I think the previous owner gutted it. It doesn't do much muffling and I suspect backpressure isn't an issue.
http://pickettweb.com/Porsche/engine3.jpg

It really depends on how much boost your gonna run.....I would say
425HP at the crank.

I'm shooting for 1 bar boost in 3rd gear.

I look forward to seeing how long the trans lasts.
I would like to keep my 915 in my future 3.6 turbo in my 72 but I keep hearing it will blow.

Hope she holds.

I agree. I really like the 915. I'm actually pretty easy on the trans in terms of shock (I don't drop the clutch or power shift). I do think the torque is going to catch up with it sooner or later, though. Rarlyl8 has had pretty good luck with his if I'm not mistaken.

my guess at 15lbs is 417 hp , now to get nitpicky are the numbers gonna be sae corrected hp or observed?? :)

I was going to report SAE corrected numbers for the purpose of the contest. Elevation of the dyno is around 350 above sea level and the temperature tomorrow should be in the low 80's. The weather is supposed to be partly cloudy. I suspect that there won't be much difference between SAE corrected and raw DynoJet numbers.

My guess is 395 hp

427 hp
403 ft-lbs

I'll take the stock wastegate spring. ;)

-Rod

Oh, I know, I know, Oh Oh SmileWavy...

Very similar setup from mine except you got the EFI goodies and twin plug. Since mine on a DynoJet 249C got 403 RWHP/390 RW Torque, I say you should be somewhere around 440.233 RWHP and 440.245 RW torque +- .001 ;)

During my dyno run, I filled my tank with VP MS109 just to be safe :D

Make sure you have a big a** fan blowing in the back and maybe put a big cardboard tilted 45 degree deflecting air down to the IC.

PS is a measure of Power used in Germany for awhile...

No OCF for me this year and I hope that is not the same Marianne who has an office next to mine...

Since you didn't like the PS units I will change my guess (estimate) to -- let's see now --

73980.35 calories/sec.


And if you don't like that one, then how about...

3.0959 * 10^12 ergs/sec ?

My guess is between 350 and 375 for hp at the wheels.

415hp is my guess.
392 torque.

I accept your 73980.35 calories/sec estimate (just slightly higher than my own estimate). Not the same Marianne. I followed mine out there when she went to UofO and then followed her back to NC. Eugene was a great place to live and you have all of those nice mountain roads close by.

Where are you located Mike? And where are you getting the dyno tuning done?

Good luck!

I'm in Concord.

Just wondering how far away you are...

Brian

Hi Brian,
I'm over in Durham. I usually use Jeff Creech over at Carolina Auto Masters for dyno work. He's a Corvette guy but he's really good to work with :)

427.5 ft-lbs of torgue with 432.5 HP

389 bhp. With other words, around 354hp at wheels.

1 bar boost and 50 lbs injectors will be the limiting factor here......I'm gonna say 460 rwhp with around 425 lbs/ft of torque.

If using a DynoJet 248C, I'll say 445 RWHP and 420 RWTQ.