ZR-1 Net Registry Forums - View Single Post - Anybody swap 93-95 (405hp) exhaust manifolds and cats to the early engines?

Hib Halverson · 12-30-2014

The 93-95 manifolds were changed to eliminate a reversion problem which, if the engine was in decel and any cat substrate was loose in the space ahead of the cats, it would get sucked into a cylinder though an open exhaust valve and damage the engine.

Unfortunately, that cost 5-hp but they gained 35 from the changes made elsewhere in the engine so the net was 30-hp.

12-30-2014	#5
Hib Halverson Join Date: Jun 2005 Location: CenCoast California Posts: 898	Re: Anybody swap 93-95 (405hp) exhaust manifolds and cats to the early engines? The 93-95 manifolds were changed to eliminate a reversion problem which, if the engine was in decel and any cat substrate was loose in the space ahead of the cats, it would get sucked into a cylinder though an open exhaust valve and damage the engine. Unfortunately, that cost 5-hp but they gained 35 from the changes made elsewhere in the engine so the net was 30-hp. __________________ Hib Halverson Technical Writer former owner 95 VIN 0140 current owner 19 VIN 1878