Anyone want to take a guess at the HP & torque of this engine-Don't have access to a dyno! 400 sbc standard bore and stroke-13-1 pistons used with 76 cc 441 heads stock rebuild with good springs-Comp284 xtreme hyd. 507-510 lift-RPM intake-Holley 750 vac.-1 5/8 headers! any help would be much appreciated!

I ran a quick DD2000 and get 500ft lbs @between 2000-4000RPM and 390hp. I used the 13:1 CR with low performance heads. Any porting/polishing done to those heads?

I got almost the same but I used an airflow file for those heads that I downloaded of the net
400 hp, 475 ft. lbs using stock bore size,13:1, headers, 750cfm,dual plane,
xe294h-10 cam

Red what size valves did you put in DD?

Originally posted by turbo:
Red what size valves did you put in DD? I didn't know the size off hand, so I did a search and found 1.94/1.50. I also found a truck head with smaller valves, so I used these ones. Did I use the wrong size valves?
P.S. Nice car you got their turbo.

There's six of them for our original design motors;

2.02"/1.60", (hi-po's, generally around 66 cc's),

1.94"/1.60", (stock 400's, as big as 80+ cc's),

1.94"/1.50", (stock 400's and all the other motors bigger then a 250hp/327, from 62 or so on up to 76 cc's),

1.84"/1.50", (305HO motors, mine measured 55 cc's but are generally 58 cc's or so),

1/72"/1.5" (all the smaller hi-pos and regular motors, 60 or so cc's???), and finally

1.72"/1.38", (267 motor, DON'T KNOW, maybe 50 to 58 or so cc's????)!!

pdq67

Thanks!
No I used 1.94/1.5" also because I wasn't sure either but I don't know if it matters or not since I had the file with the flow #'s to plug in??

Thanks for the Input! the heads have stock replacement 194-150's-no porting! I am guessing that the compression will be about 11-1 with these heads-38 thous comp gasket-about 74-76 ccs! I am guessing about 380 hp-450 TQ! Using 25% racing gas 75% 93 pump gas 35 degrees timing!

running again with the lower compression this is what I got(first time I used 13:1)
375hp at 5000 rpm and 450 ft lbs at 2500 rpm
should pull pretty hard graemlins/thumbsup.gif

Here's some info for comparison.
I have a 383 with 10.75:1 with the same cam. The only big difference (other than the cubes) is that I'm running AFR195's.

With a Performer RPM manifold and a Holley 800dp I put down 362/398 to the rear wheels with a broad flat torque curve. Here's a graph. (http://www.chevelles.com/showroom/Matt_Leuck/Dyno4small.JPG)


- Matt