Thread: 355 build HP and Torque?

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Update on this thread: (5/31/2012)
I have edited this first post for the benefit of those who haven't read the subsequent remarks and followed along on my evolving engine build journey.

If you are looking for pictures, I have posted a bunch of them starting somewhere about page 3 of this thread.

Initially I started this thread looking for advice and directions, and believe I have hit gold when it comes to good advice.

My newly revised goals are:

Build a 350-400hp 350 engine with good low end torque and street manners that will perform impressively in my 3500lb 67 Camaro while running on cheap pump gas.

Initially I considered rebuilding an original 327, but am well on the way to putting together a roller cam 350 as shown:

Here is my original posting: I hope you enjoy the read and I appreciate your patience as I am learning as I go, Thanks, Rollie

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I'm building a 355 and have just about decided on most of the components. I am impressed by many of the comments I have seen by others here particularly techinspector1 and was wondering if he or someone could run some numbers for me. The CompCam software using the following specs predicts this combo to be somewhere around 400hp, 462torque, but I think that is high. What do you think? (See note from dyno-sym output at end of this post)

Some of these are based on my own spreadsheet calcs.

89 350 block w/ roller lifters
3.48 stroke
4.020 bore
Deck 9.013
Piston pin to top 1.561
Piston to Deck .012
Head Gasket GM 14096405, compressed height 0.028"
Quench 0.040
Vortec Heads 64.0cc (after milling) w/26915 beehive spring set
KB142 Pistons 18cc D-Dish
Static Compression 9.1
Dynamic Compression 8.2
Cam CompCam 08-410-8 260HR IVC=29 ABDC @.050
Edelbrock intake manifold, 2716 Performer Vortec EPS
Proform 67207, 650cfm carb, vacuum secondarys, electric choke
Full length 1-5/8" headers, Hooker -2130-xHKR
2-1/4" dual exhaust
Hooker Max Flow mufflers with H-Pipe

And what ever other variables I need to run a sim.
Thanks
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02-12-2013
Here's an updated cut and paste from a different thread after techinspector1 ran the numbers on his dyno sim program: (thanks Richard)

RPM HP TQ
1000 59 310
1500 103 360
2000 155 406
2500 200 420
3000 237 416
3500 274 411
4000 304 398
4500 317 370
5000 312 328

My first impression after seeing these numbers, was a little bit of disappointment. In my mind I was hoping for Horsepower numbers somewhere close to the 400 hp range, and the 317 peak at 4500 rpm in this table was quite a bit short of that. On the other hand, the Torque numbers are very high, in fact the peak 420 ft lbs at 2500 rpm and the flat torque curve from 2000 to 4000 rpm match or beat many of the 400+ hp engine builds I have seen. If you look closely at many of the 400 hp engine torque/horsepower curves, they will look similar to this chart up to about 4000 rpm except they continue to have strong output into the higher rpms where they reach their hp peak. I'm thinking now, for a street driven car, my engine build should be quite comparable to many higher hp engines, particularly when the rpms are kept at the low to mid range as typically used on the street.

As an interesting note of trivia, regarding my drive to build this engine, part of it is nostalgic, as I am somewhat trying to recapture experiences I had 30 years ago when I owned a similar 67 Camaro with a 400 hp 327. Looking back, and knowing what I know now, I'm thinking this new engine with a 700R4 and 3.55 rear end, will actually have better launch then my old high revving 327 with a TH400 and 2.73 rear end.

We will see.