« on: Mar 26, 2009, 09:29:16 PM »
The 20R engine is a cross flow design and does not preform well without back pressure.
Back pressure is needed to slow the air flow and produce more power.
I recall removing the factory cat and driving my '80 with the open exhaust. It had no power.
Marlin
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1980 Toyota - 1997 3RZ-FE 2.7l Engine, Turbo R151F 4.31:1, Triple Turbo Marlin Crawler Billet (2.28x4.70x4.70) = 1,148:1 Crawl Ratio, Marlin Crawler Twin Stick and Short Throw Shift Kits, 30mm H/D Output Shaft, High Angle Drive Lines, 5.29:1, ARBs, High Pinion Front, 25mm HD Billet High Steer Kit, 6 Pin Locking Hub Bodies, 86+ Wide Rear End, V6 3rd member, Chromolly Axles all around, 37" IROKs with Beadlocks, York onboard air - Rollbar air tank, Premier Power Welder, Marlin Crawler 4" USA-made Leaf Springs, Bilstein Shocks, et cetera....
