Monty

bInteresting article in the August issue of Hot Rod.
Take a stroked 327 ci SBF with common aftermarket parts, and compare the performance of the engine with commonly available Centrifugal (Paxton Novi 1200), Turbo (HP Performance T62-1), and Roots (Holley 174) supercharger kits. Boost was limited to 9.5psi, non-intercooled.

--------------------------------Baseline------Centrifugal------Turbo--------Roots
Peak HP---------------------392@6000------617@6000----600@6000--535@6000
Peak TQ---------------------386@5200------561@5200----617@4200--513@4600
Min Boost--------------------------------------1.7@2500-----5.7@2500--4.8@2500
Max Boost-------------------------------------9.5@6000-----9.5@5100--8.0@6000
Ave HP(2500-6000rpm)-------310-------------412------------460---------394
Ave TQ(2500-6000rpm)-------365-------------494------------564---------483
Ave HP(4000-6000rpm)-------352-------------518------------555---------472
Ave TQ(4000-6000rpm)-------371-------------542------------585---------497

TQ@2500-----------------------------------------360------------490---------440
TQ@3000------------------------340-------------405------------500---------450
TQ@3500------------------------355-------------450------------560---------475
TQ@4000------------------------365-------------500------------610---------500
TQ@4500------------------------380-------------525------------610---------505
TQ@5000------------------------375-------------555------------600---------505
TQ@5500------------------------355-------------555------------560---------485
TQ@6000------------------------354-------------540------------530---------475

HP@2500-----------------------------------------170------------235---------210
HP@3000------------------------190-------------235------------290---------250
HP@3500------------------------240-------------300------------375---------325
HP@4000------------------------275-------------375------------455---------375
HP@4500------------------------325-------------450------------525---------445
HP@5000------------------------360-------------525------------575---------485
HP@5500------------------------380-------------575------------600---------510
HP@6000------------------------395-------------617------------600---------535


[Modified by Monty, 5:53 PM 6/28/2003]

SloRvette

Wow, if you just looked at peak numbers you'd think the centrifugal would be the winner. The average numbers tell the real story.

scorp508

I wonder if there was a reason the roots only went up to 8psi?

Monty

The Roots SC was too small for that engine. Even with the smallest pulley they could only get 8psi. Thye mentioned in the "Conclusions" section that they should ahve used a 6-71 or 250 Powercharger.

Z-man

They also missed testing a twin-screw (Lysholm) type...would have liked to see similar specs.

Aaron's 87

How did the roots only make 4 psi at 2500? Some kind of mismatch. At least they put a bunch of disclaimers at the end.

yellow 72

some forced induction for your viewing pleasure....
http://fasttrackperformance.com/page.../ChrisTTGN.wmv