when i bought my 1998 4x4 quadcab slt larime v8 magnum, i thought it had the 318 in it. but i quickley realized it is a 360. So my question is i feel like i should have alot more power than i do. shouldent i be able stand on it at a stop light and just smoke the tires. i am getting about 9 miles 2 the gallon driveing in town, so i changed my spark plugs and air filter. it didnt help either issue at all. it has 170 thousand miles and my tite size is 75r16, anyone have any advice or tips????

 

I advise you look around the forum and try doing some searches. There's lots of threads on getting more power out of these trucks, but the reality is that they are not screamers (well, my V10 is, but the V8s...not so much). There are a number of issues inherent to the V8s that can cause poor mileage and bad performance. Try a search on plenum gasket for a start.

 

plenum gasket is blown. with 170K definatly

Take the air breather off. and look down into the throttle body. if you see oil, its blown.

i just replaced mine. quite easy to do might i add. but if you do do it, ge the hughes reienforcment kit. it makes it so you dont have to replace the plenum again. if you repace it with a normal gaske, it will last maybe 50K

i was getting 9-10 miles city about 13 highway. and this is no joke. i changed the plenum, im now averaging 13-14 city and about 18 highway, and the power i have now is awesome

 

sorry to say but if i rember right these 360s only have like 250hp at the wheel so theres not a alot regear it with 4.10s new intake headers roller rockers and you should be just fine then but just search around on geting more power out of theses motors

 

+1 i love my 4.10s

 

It's 250 at the crank, not the tires. Roughly 200ish at the tires. Not much at all, especially in a big truck like that.

 

question on replacing the plenum gasket what is the average time frame on the job?

 

ooo thats right
still 250 is bad enoff but 200 is just sad

 

also check the cat

 

took me a total of 18 hours. 6-7 hours of cleaning. then at the end, about 2 hours of BS'ing cuz the fuel injector o-rings leaked, and i routed the dist. cap wires wrong.

also i changed the thrmostat. Dis.cap, valve coer gaskets as well and that time is included in the 18 hours. also the half hour to bleed the cooling system


but all in all it was a really simple job. Only special tool i needed was a fuel line disconnect