I have a 2004 4.2L GM Envoy with 50,000 miles on it. The engine is not powerful enough to pull my 21 ft travel trailer and maintain a reasonable speed. Is there room in the engine compartment to accept a 5.3L active fuel management engine and if so what should I expect to pay in NJ for the switch?

I wouldn't even consider attempting something like that. The dimensions are the least of your problems. The entire management system is for the 4.2 and the computer and all the wiring in the truck would be different and incompatible, not to mention it would totally be against Federal law to make a change like that and drive it on US highways. That is an emissions certified vehicle and cannot be modified legally.




78 Corvette Pace Car For Sale-18k mi orig-Florida