you can always go with custom pistons and rods. i have a 1969 GTO Judge with a 428. it has a 4.18" bore and 4" stroke. it will run me $600+ to get a set of ross pistons. i can save money and get the rods that are sized to a BBC but if i want to stick with the pontiac journal size then it will be quite a bit more. i remember reading a article about a Syclone thats in the 9's and he had custom forged everything to handle it so it can be done.

 

If you want to know bout pistons check out hotrod magazine, search for high performance 4.3l. The rods are different i'm afraid, this I know. I think the pistons are the same, but I'm sorry, I can't remember. If I were you, I would start with an intake, head work, and a Cam K-Kit, see what you think of that before going all out Forced Induction. GL

 

you might want to talk to a company that makes chips and find out exactially what you can get away with before you have to srart getting diffrent chips or a whole new computer. thats why i love my 69 GTO judge no matter what head/cam combo i can think of i dont have to get a computer burned to what i have. i have a friend at work that has a 80 somethingcamaro 5 speed with a 305. he put a mild cam in it with a bigger set of roller rockers and upgraded fuel system along with an exhaust and he called up JEt i think it was and told them everything he has done so far and what he wants to do in the future and he got a custom chip made. if youre going to go overboard with the bigger stuff first that might be somethign to consider. personally i would start off with small stuff ( fuel,ignition,exhaust, ) and see if youre happy with what you get and in the long run it will make the bigger stuff ( heads,cam...) work better. im new to the vortecs myself and im trying to figure out what the aftermarket has to offer as far as small stuff.

 

I don't get why the 4.3L V6 isn't as fast as some of the 3.0L or 3.5L V6. It is a very nice engine and for a V6 its freakin HUGE. My question is how come the 4.3L just doesn't have the power or hp as some of the smaller v6's? I think it should be fairly quick. But im jw if you guys know! thanks


(i have a 2002 LS 4dr 4x4 Blazer)

 

You are comparing apples and oranges. The 4.3L engine is designed for torque to move a truck. That and it was designed a LONG time ago and is not taking advantage of much of the newer technologies like many other engines are. The 4.3L is a workhorse that will last a VERY long time with proper maintenance.

 

Yeah, i guess your right. I believe that It's a work horse, and will last a long time. But i see what ur sayin about new modern technology. It just seems it could have better acceleration and even top speed, but i suppose that ur right and that it was designed for torque. Isn't it based on a small block v8? Idk, i just heard that so it may not be true.

 

it true. same as the v-8 except two cylinders are chopped off...

 

It can be made to run better at the top end, but at the expense of low RPM torque. A cam swap can completely change the operating characteristics of the motor. However, to get even more out of it, you really need to do some port work on the heads and a different induction setup (intake, throttle body, injection), headers and a good exhaust system. Get it all together and you've spent way more than most people want to.

Newer engines with variable valve timing, 4 valves per cylinder, etc can be made to have good torque down low and excellent HP up top (4.2L I6 in my Rainier for instance w/ 240ftlbs of torque off idle maxed out at 275ftlbs and 275HP).

 

the 4.3 is a 5.7 with 2 cylinders shaved off
ALL of the specs bore,stroke are the same
i found a stroker kit online for the 4.3s for around $700
kit includes crank ,rods,pistons
just like turning a 350 into a 383

 

Oh thats cool. I didn't know that. Does anyone know the reason why they put the 4.3 v6 instead of the 350? gas maybe? ?