GM TPI in the 400 SBC

[ECMnut at aol.com]

Skip this post if you could care less about 400 SBCs
or drag racing..

With such a low RPM torque peak, some conservative
rear-end gears (3.55-4.10) will probably work well.
Peter mentioned traction linitations in a previous post.
I couldn't agree more.  IF you can keep it connected
to the pavement, the car should provide big fun..
The 400 SBC makes lots of torque without such a
TPI intake amplifying the issue.  With the stock runners, 
it should REALLY make torque by 3,500 RPM.   
Some years back, I had a 2700 lb bracket car with 
a 350 SBC, 5.13 gears decent heads, very mild hydraulic
 cam and a box-stock 750 Holley.  It turned 11.70s all 
day long.  It idled as smooth as a hoover vaccuum cleaner.  
Eventually, I replace the 350 shortblock with a 13:1 400 
shortblock, reusing the heads, cam & everything possible..
I reduced the rear-end gear from 5.13 to 4.10 because I was 
nervous about turning the "strokey" short-rod 400 too hard.
The first day out with the 400, it idled perfectly smooth at 
15 inches of vaccuum, and the car turned 10.80s....
Almost a full second improvement over the 350..
Even with the gear reduction, the car left the starting
line much harder than before.  A hard throttle stab
from a fast idle would pick the front tires up almost 
a foot.  The car was a small Vega with a 3 link suspension
and 14 inch wide slicks, so traction was usually available.
If I could have EFI'd this thing, I'm sure it would've been
faster and cleaner.  Even with a carb, I considered 
getting a tailpipe emmisions test done, but never found 
the time.  The engine stayed in the car until two years 
later, when I sold everything..
The 400 is really impressive as long as you keep the
RPMs low (below 6,000?)..  That includes the burnout.
Despite my persistent warnings about hi RPM death,
the rookie that bought my car liked the sounds of 8,000
RPM in the burnout area, and put a rod through the 
oil pan his first day at the track.. 
Good luck, I bet the 400 TPI combo will be fun..
Mike V