3800 / 3400 Hybrid

[ezrollin]

What would you use for a turbo project / S-blazer.The 3800,99 lowmileage, needs upper intake and camaro trans;would require fabbed mounts. The 3.4 would require 3500 topend and total rebuild[no problem] but is basic swap. Both would require forged pistons for boost. I'm leaning toward the 3.8 because of the extra cubes and parts price/availabilty. Give me your input on this,any problems you foresee. P.S. the S-blazer now has SBC V8 with auto.

[sharkey]

3800 is an outdated design with inefficient heads and a heavy motor. the 3400 will put out more power due to the more efficient cylender heads, and its a lighter motor. parts are getting easier to get for the 3400 now and with a swap like yours headers and such would be custom anyways.

[ForcedFirebird]

I plan on having my hybrid running by March so we will soon see what it's capable of. It's going to be a 3.4/3500 with RWD pistons at first for some N/A testing, then boost is going back on. 250hp is the goal for a dyno run @ 13ft above sea level.

A 3.4/3400 has been proven to get almost 200hp in an fbody (4th gen) on a chassis dyno with a 262 cam and stock big port heads. A 3800 puts out 180hp in the same car.

The 3800 weighs more, and won't rev as high as the 3.4/3x00.

Guess I'm biased, lol.

[ezrollin]

The 3.8 is rated 200 hp@5200rpm and must be pretty durable because it's been around so long but I'm not here to defend the 3.8, just stir up a little debate. Actually I like the 3.4 ,except for the cost of custom forged pistons,it lends itself to the easiest install and would be just plain cool with the 3500 topend.

[ForcedFirebird]

The 3.8 is rated 200 hp@5200rpm and must be pretty durable because it's been around so long but I'm not here to defend the 3.8, just stir up a little debate. Actually I like the 3.4 ,except for the cost of custom forged pistons,it lends itself to the easiest install and would be just plain cool with the 3500 topend.

Don't get stuck on forged pistons making the decision, no matter which engine you choose, they are going to cost you about $600. You can defend the 3800, I'm all over the fbod forums and they all think the 3800 is better just because it's bigger, but weight comes with it. I shaved well over 40lbs off the front of my car by swapping from iron heads, which is not an option with the 3800. The 3800 is on it's last leg from GM, the 60*'s are replacing them . The 3.4 short block I just had delivered weighed 220lbs with the pallette included...

http://s158.photobucket.com/albums/t...ild/?start=all

As Joseph Upson has posted several times, how often have we seen pistons fail with boost? I detonated at 7psi like you wouldn't believe. The motor hasn't come completely apart yet to see if a rod got bent, but the pistons look good, even though the bearings look like they were smashed with a sledge hammer. I have seen over 30psi on cast pistons pushing a 4cyl into the 10's. Detonation is your enemy, good tuning id the absolute key to boost. even the 3.1 turbo never came with forged pistons.