I just installed a Jacobs exhaust brake and a 4 inch down pipe and was wondering if the stock valve springs weregood enough or do i need to upgrade the valve springs to the the added stress of the exhaust brake? Any info on this would really help. Don't really feel like breakin a spring or anything like that

 

Exhaust brakes require heavier valve springs on the exhaust valves on 12 valve engines. You don't want to float them open when you use the exhaust brake.

 

As I understand it, the "valve float" JD730 refers to is rather more than just an inconvenience. If the valve is held open when the piston reaches TDC, major damage can result. BD, and probably others, sold a brake with reduced backpressure for trucks with stock (30 pound?) springs but that reduces the effectiveness of the brake.

To be safe, better install the 60 pound exhaust springs.

Dan

 

Thanks guys i am just gonna go ahead and put 60 lb springs in all the way around along with a 4 k gsk.

 

The GSK, after the springs of course, will make you smile once you get it set up. I had a 3k GSK on my '98 and it really helped me get up to speed, quickly. Be sure to check your Gov. lever contact after installing GSK. Mine was going under the plate until I adjusted it.

Dan