lacking power pulling 4000 lb boat up hill.is there an after market tbi I should change to or any other ideas.thanks much clark

 

fuel pressure,cat clogged did it always do this or did it start recently

 

runs great all the time when not pulling the boat,but when pulling the boat up a good hill it just seems to be weak.not a stong puller up hill.runs great up hill when not pulling. 454 2wd 3/4 ton thanks for replying

 

In Drive or Overdrive?

 

how many miles? that is an old engine that is probably pretty tired at this point so needs some TLC. even new I think those were around 235 hp and 375 tq and do you have the 3 speed transmission? if so that doesnt help any with towing...

but you need to let that beast breathe - go to jet.com or other aftermarket sites to replace the throttle body and intake manafold, then go to the exhaust - add headers, replace the CAT and make sure all of the exhaust pipes are sound or replace them

I used to have a 1990 single cab Chevy with the 350 and it ran VERY strong once I did those engine upgrades.

 

I always tow in Drive not O.D. , the engine has 96,000 miles on it.I just had it smoged (california)passed . The tech said sounds like not getting enough gas when pulling up hill, to change tbi as you say so I will check out jet.com . thanks for the replies clark been checking not much luck finding tbi for 454 I need to look more tomorrow

 

Had similar problem on mine. turned out the little bushing type bearings on the distributor shaft were totally worn-out, causing the timing to be off as much as +/- 10 degrees...randomly! replaced the whole distributor for minor cost, and power change was amazing.