NA power on carbed 3.4

[alvarez1112]

Alright guys I'm starting a slightly different project and I need some help. I'm building an airboat and want to use a 3.4 I have lying around. The goal is to make as much low rpm power and torque as I can the biggest set back being this will be a carbed motor as electronics aren't the way to go when you're running around in the swamp.

As it sits the motor is stock with a tbi intake that mas in my s-10 before I swapped in a small block. I have a brand new set of 3400 alum. heads that I bought for a top end swap again before I swapped motors, so those are lying around as well. Can I swap the heads build an intake, stab a distributor in it and make it go? Obviously I doubt it's that simple so tell what you think. Any help would be much appreciated! Thanks

[3100 MPFI]

if you can build your own intake that can use a carb, and have a non electric supply of fuel (seeing you said you don't want electronics), then yes, it really is that easy. Seeing all of my experiances are with the GEN 2 and GEN 3 engines, which are fuel injected, I don't know how the mechanical fuel pumps work.

[bszopi]

The biggest hurdle would be fabbing up the lower intake so that it would clear the distributor. Normally, this wouldn't be an issue, but since the 60V6's lower intake completes the top end of the heads, it becomes a bigger PITA. (Someday I will fab up a brand new lower, but not anytime soon.) If you can do that, then hell yeah, go for it. But I see that as being the one (BIG) issue with your plan.

[candychevy87]

you can use an intake manifold from edelbrock to run the carb, hell of alot easier than fabbin one, but the thought of an open header (all swamp boats run open headers if youre cool) 3.4 at wot goin through the swamps sounds really interesting,

[geoffinbc]

If he uses the Edelbrock intake then he can't use the aluminum heads. The other problem will be the pump for fuel. You will have to work on a belt drive. Or if you are cool with just an electric pump it would be easy to make that work too. Your going to need at least a basic 12V electrical system for starting, charging, lights, and gauges I'm sure.

If you are just looking for low end torque iron heads with a carb would be much easier to implement than aluminum heads. Iron heads wont limit you (much) from building low end grunt.

[alvarez1112]

The boat will have an electrical system what I meant was that there's no may I'm running an ecm to control fuel and spark. Fabbing an intake wouldn't be a problem but it may not be worth the effort. I just thought there was power to be had with the head swap. Think the normal 272h cam and a set of springs with an edelbrock intake may be a better way to go? All I really want is like I said low end grunt and somewhere around 160-180 horsepower.

[geoffinbc]

Well don't get a 272 cam if you are after low end grunt. That cam makes its torque peak up high. Your better off with a Comp 252 cam if you want low end torque. You will get an easy 200lbs of torque at 2000RPM with the 252 cam. That's what my dyno program spat out anyway and it was bang on the stock GM rating when I tried the stock GM Camaro Cam.

[candychevy87]

damn what kind of engine calculator do you have, mine dont do that crap

[Superdave]

the comp 260 or crane 260-2 might work pretty good in this app as well.


you could always up the scr by swapping in some 3.4 DOHC pistons.. that'll help out the bottom end torque.