btw, I disagree on your assumptions on what a 383 does.... I agree it doesn't automatically add 50 hp, but with everything being the same on a tuned port application, it will add roughly 20-30 hp as we've seen in many different applications including myself.

Regarding air flow:

Here is some very valuable information in the December 98 Hot Rod in the article titled: " TPI: 10 deadly sins "

Stock Runners: 203.17 cfm
Accel long tubes: 242.02 cfm
Superram runners: 289.18 cfm
Edelbrock Performer RPM manifold: 286.51 cfm

Total runner lengths are (From plenum to valve seat)
Stock TPI: 25.275"
Superram: 21.125"
Performer: 12.125"

The article is very good, and by coincidence the very 1st deadly sin when modifying a TPI motor is "Don't use the Stock TPI, on a fully optimized motor it cannot support anymore than 350 HP because the stock TPI was designed by GM for a 305 cubic inch motor"

The article is written by well respected automotive engineer Ray T. Bohacz and really is an enlightening article for 1st time users to TPI.

If you would like, I can FAX the article to you... I would scan, but I do not think my scanner has the resolution to create a decent image.

Regardless, I look forward to hearing about your finished results on your 87.... I personally think you are going to come considerably short of your 400 hp goal, but good luck.

cheers,
Beach