How much HP gain by removing cats? - ZR-1 Net Registry Forums

QB93Z · 06-14-2008

I attended an event called Vintage Thunder - A Day at the Races put on by the Mason Dixon Chapter of NCRS. It was held at Cecil County Dragway in North Eastern Maryland. We spent the morning making time trial 1/4 mile runs and then had a single-elimination bracket race in the afternoon.

I had the only ZR-1 there. The crowd was mostly C5 and C6, but there were a few olders Corvettes as well.

The event was very well run. Thanks to the Mason Dixon Chapter of NCRS for putting it on.

This was my second outing at the drag strip running my 1993 ZR-1. This time was different because I removed my catalytic converters. The change in performance was dramatic compared to last month in Beech Bend. (Not my performance, the car's. My 60 foot times still suck.)

My best run run was a 12.9 at 112.8 mph. My best top speed was 115.7 mph.

The average ET improved .13 seconds and the average top speed went up by 4.1 mph (109.78 to 113.87).

I have a stock LT5 with headers, 4.10 rear end and a Corsa exhaust.

Removing the cats did not improve my 60 foot times at all. No surprise there!

In the past I have seen a comparision of the HP needed to change quarter-mile top speed. Can anyone estimate the HP gain I got by removing the cats?

Thanks,
Jim

06-14-2008	#1
QB93Z Join Date: May 2007 Location: Westminster, Maryland Posts: 3,689	How much HP gain by removing cats? I attended an event called Vintage Thunder - A Day at the Races put on by the Mason Dixon Chapter of NCRS. It was held at Cecil County Dragway in North Eastern Maryland. We spent the morning making time trial 1/4 mile runs and then had a single-elimination bracket race in the afternoon. I had the only ZR-1 there. The crowd was mostly C5 and C6, but there were a few olders Corvettes as well. The event was very well run. Thanks to the Mason Dixon Chapter of NCRS for putting it on. This was my second outing at the drag strip running my 1993 ZR-1. This time was different because I removed my catalytic converters. The change in performance was dramatic compared to last month in Beech Bend. (Not my performance, the car's. My 60 foot times still suck.) My best run run was a 12.9 at 112.8 mph. My best top speed was 115.7 mph. The average ET improved .13 seconds and the average top speed went up by 4.1 mph (109.78 to 113.87). I have a stock LT5 with headers, 4.10 rear end and a Corsa exhaust. Removing the cats did not improve my 60 foot times at all. No surprise there! In the past I have seen a comparision of the HP needed to change quarter-mile top speed. Can anyone estimate the HP gain I got by removing the cats? Thanks, Jim __________________ If it isn't fun, you aren't doing it right! 1990 Black ZR-1 - sold 1993 Quasar Blue ZR-1 1994 Competition Yellow ZR-1 1995 Dark Purple ZR-1 Maryland State Coordinator WAZOO Member