hines182

I've got a '98 k1500 with a 4.3 and I'd like to start modifying it for off-road use. Of course with bigger tires, it's always nice to have more power. So my question is has anyone here ever built up a 4.3 Vortec, and was it worth it? I like having a truck that's different so I'm open to building up my 4.3, but I'm also ok with finding a wrecked donor silverado with a 5.7 and swapping. Got some input?

jcbst12

Bigger motor is always best for off roading because of the torque demands, "no replacement for displacement".

An89Chevy

i agree with jcbst12, the 4.3 just doesent have the tourqe, best to go with a 350, do you have a 700r4,th350, or manual trannythats just as important. to tell the diffrence...

700r4 4-speed auto

th350 3-speed auto

hines182

it's a 5-spd manual. not sure what model exactly, but i'd like to stick with a stick if i can.

jcbst12

A manual requires more skill for 4wheelin, but its more rock solid than an automatic if mated with a heavier clutch.

MalibuMaxxSS

Yes power is good, but this statment kinda makes you wonder why some of the best wheelers are Samurais and trackers with a 1.6L engine.....I would be more inclined to change the gear ratio in your rear end and front diff, so say a 4.88....this way you can keep you stock motor and be cheaper for you then swapping a 350 in there, and If your gonna swap motors, get yourself a 5.3 or 4.8 from a newer chev....

I do somefunmud and rock wheelingwith YJ and an inline carbed 6, only about 3 of the 30 or so guys run small blocks, and full sizes, most run Jeeps, Cherokees, Samurais, and trackers..

Remeber you have low range, its not about power all the time.....wheeling requires skill not HP....If I were you I would thro some gears, and full uspension lift, maybe lock the back.....but lockers are tricky as well, requires a whole new driving techniques, fun in snow....LOL

An89Chevy

another thing to think of is weight, trackers are good in the mud because there so light. your truck is kinda heavy especially with a 4.3 your weight to power ratio is weak, you can put in different gears, and take off some weight.

i would still go with a bigger engine, are your gonna use this truck for off road use only?..

MalibuMaxxSS

It dont matter how much HP you have without the proper gears you wont turn them anyhow, my Jeep makes all of 167 HP last time I checked and it turns 37' swamperstires, with 4.88 gears, and whales....now one other fellow we wheel with has a SB 350, uses a 700R4, with shift kit, and 3.05 gears, and 38 boggers...in high range the truck WILL NOT turn the tires in mud, he has to use LOW RANGE......why his 3.05 gears........put some 4.10 and he is stylin..

HP is good IF you get it to the ground......your S10 prolly has 3.73 or 4.10 in it, if so check on 4.88 or even 5.12, this will give the umph your looking for, without dumping endless amounts of $$$ in engine and tranny swaps that never work right together..........then you need to weld motor mounts, tranny mounts, driveline angles, longer or shorter drive shafts, computers, EFI systems, or go crate and get carbed which is its own set of problems....

Maybe I dont off road for a career but do it enough that you want to keep things simple...breaking on the trail sucks hard core, and not knowing your own Rig sucks worse, and messing with some engine/tranny/computer/suspesion/etc, someone else did sucks even more.....if this is gonna be a solid off roader only, and you have ample $$ then swap engines....if you dont have ample $$$ gears, lift, and maybe a locker and your golden.......

The Samurai in my avatar is not mine its my buddies, it is upgraded nowwith full width toyota axles, runs a spring over, with 37 Super swampers, a 8000lb winch, all his lights, and carries all his gear in and out of the bush.....only thing NOT touched is the MASSIVE 1.6L 98hp THATS RIGHT 98HP....engine.

jcbst12

Samuris are so much smaller and nimble tho. These trucks are heavy and I know from experience that without a major gear reduction big tires and low climbing speeds are going to kill a six. But using a v8 will give you offroad power without killing onroad drivability. You can find a better mix between power, torque, mph and onroad driving. I do agree with the 4.8 and 5.3 enignes. They breathe well and are pretty damn durable.

Can't go wrong with a well tuned carb'ed 250 either.

jcbst12

Sorry 350 not 250.