blazer 3.4 best cam to use?

[isphius]

I picked up a decent running 4x4 blazer, its going to be used to haul band gear and do a little offroading. It is a TBI. My plan is to grab a 3.4 block, and use either the stock 3.4 heads, or i believe that i read the camaro 2.8 heads had bigger valves or flow better or what not? Anyway, will either of those 2 heads work with the TBI intake? 2nd question, i want a little more cam out of it. I know the stock cam specs are tiny. I want a little more power after the 2400 rpm range or so, because on the highway or offroad its somewhat easy to avoid lower rpms. So im basically looking for a cam that will make peak power around 2600-3000 or thereabouts, with good rpms and torque. Its going to keep stock tires and suspension, maybe just a 2 inch lift or so, so torque isnt my main concern as i know the 3.4 is still pretty small. Ive searched around and didnt find anything in specific, its all about high rpm horsepower etc. If someone can point me to a good thread and delete this one if you must, that will also be appreciated. Thanks, Joe

[Superdave]

all fuel injected iron heads are the same so the ones from the 3.4 will work fine. I'd go with a Comp 260 cam and a set of 1.6 rockers from a '94/95 3100 V6. With good valve springs you'll be in good shape.

[geoffinbc]

I would also go with the comp 252 or 260 cam. If you plan to go offroad and like a little more pull at the bottom end (from about 2000RPM) then go with the 252 cam. If you want a little more top end horsepower than go with the 260 cam. I would just buy the whole COMP cams K kit. Its a steal at just over $300. I would also buy the magnum 1.6 roller rocker which you can also get in a kit with pushrods for around $150.

When you get your 3.4L. Gasket match the heads and blend in the valve bowl and remove all the steps and sharp edges. Also remove all the flash from the block casting, especially where the oil drains back in the lifter valley. Send it off to the machine shop and get whatever work needs to be done to the block and heads. When you re-assemble the engine gasket match the intake runners to the head ports and also have the intake bored to accept a 4.3L throttle body and your little 3.4L should be around the 200HP and 200lbs of torque at the crank. When I did some Dyno sims with a 252 cam on a 3.1L I was getting results of 180HP and 220lbs of torque. They are never perfect but your in the ballpark.

[Superdave]

what kind of port flow numbers were you using? that seems kinda high.. lol

[ForcedFirebird]

I have a 252 and a 260h I can sell Both are nitrided and brand new in the box.

I would go with the 252, though, if you like to 4x4. It has a bit more tq than the 260.

Dynomation puts the 3.4 at about 150hp/190tq at the wheels, little less for the 3.1 with either cam, but like Betterthanyou mentioned, the 252 puts your band a little lower in the RPM's.

[geoffinbc]

I used the 252 in my Trooper build and it has great torque right at 2000RPM and maxes out around 3000RPM it will pull hills in 5th no problem and I have 33" tires with 4.55 gears. I have wound it right up to 5500RPM and it still makes ok power up high. Better than the stock cam at least.