Building a new engine for my truck...

[sterlingbrum]

So im looking into building a new engine for my truck and I'm starting to get overwhelmed with all my research. I figured it'd be easier to ask experienced people their opinions.
Specs on truck currently:
307 w/ 305 heads, dual plane intake, Holley 600cfm
Th350
3.08 gears
Long bed 2wd 1/2 ton

What I'm looking for out of the truck:
Ability to tow up to about 8,000 lbs
Ability to hold my own at the drag strip (high 13's?)
More low end - mid range power.
400hp (with or without spray) for around $1500?

Pretty much I want to use it for work if I have to (towing cars, boats, camper) but I want it to be more of a sleeper than anything.

My plan so far is to ditch the 307 obviously.
Throw in a 350 and do it for a decent price.... That's all I got haha

Questions about the build:
Best heads? I was thinking the Dart 127322. Or is there better heads for cheap?
What cam? I would enjoy something that sounds kind of agressive
Can I use my current Holley?
How hard would it be to run a 75 or 100 shot?
Which gears would suit me best?
What else do I need? Higher stall? Better fuel delivery?

[1967KaiserM715]

My $.02, you'll need better rear end gears(3:73 or better) and a better tranny for towing.


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[zieg85]

And ditch the visor, that will shave off a second...

[Farm boy]

Thought about going with fuel injection? If you want 400hp out of a 350 it'll be a semi aggressive build and will probably loose its manners. With fuel injection it would definitely help tame the beast for pulling trailers and starting (especially in colder temps). But I definitely realize it will be a little more spendy.

I plan on dropping a 500+ hp bbc in a 84 4x4 I'm starting to build. I'm going to use the wiring harness from a 97 5.7 with a manual and convert it to run port injection (aftermarket intake) and get the pcm tuned.


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[Farm boy]

Oh and keep the visor, that's a +15hp accessory lol


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[sterlingbrum]

My $.02, you'll need better rear end gears(3:73 or better) and a better tranny for towing.
Definitely planning on better gears. You don't think the th350 would hold up for occasional towing?

Thought about going with fuel injection? If you want 400hp out of a 350 it'll be a semi aggressive build and will probably loose its manners. With fuel injection it would definitely help tame the beast for pulling trailers and starting (especially in colder temps). But I definitely realize it will be a little more spendy.

I plan on dropping a 500+ hp bbc in a 84 4x4 I'm starting to build. I'm going to use the wiring harness from a 97 5.7 with a manual and convert it to run port injection (aftermarket intake) and get the pcm tuned.


I was thinking about the new EFI system Holley has out for about $1000, I'd definitely like the reliability of it. Any ideas on a good cam profile? Or specs on heads? I may run it with a carb until I save up the money for EFI too.

[Farm boy]

I am in about the same, head is spinning with numbers, boat you are right now lol. But you need to have Pistons, heads, intake, and stuff figured out then the cam is the last thing you tie it all together with. After you have comp ratio and valve size and such these guys can help you with cam numbers (as well as any big can manufacture or summit, jegs ect.)


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[Farm boy]

If you have the pockets for it the holly kits does seam to be a great way to go! Pus you can get it running with a carb n then switch when your wallet recovers from the build


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[Farm boy]

Another thought. If you are going this far do it right a build a 700r4 so you have OD.

Or a 4l80e with a stand alone computer but I doubt your pockets are that deep.


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[sterlingbrum]

Another thought. If you are going this far do it right a build a 700r4 so you have OD.

Or a 4l80e with a stand alone computer but I doubt your pockets are that deep.


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A 700r4 would be nice but that's just digging deeper into my pockets... I know my trans is in good shape so I'd like to use it as long as possible. Also I was thinking about finding a short block, rebuilding it, and adding some aluminum heads. Whats a good rebuild kit? What kind of compression should I be shooting for?

[Farm boy]

Pump gas? Regular or premium? I think you'd want to be around 9 to stay on regular n I think under 10-10.5 to stay on pump gas. Problem is that's about as much as I can help you. To get the rest of the build for the engine the you need help from someone with more experience. Sorry I can't help more


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[1967KaiserM715]

Compression will actually end up dependent on cam, I know a lot of people say a cam is the last thing to choose, but I was always taught to decide on what you want from the motor and size of motor, then find a cam that fits your criteria and build the engine around that. If you choose compression heads exhaust and intake before the cam chances are you will end up with something off, intake oversized for rest of motor, compression too high etc, plus it ends up really limiting cam choices.

The th350 will tow, but it won't last long, it just isn't built for it. A th400 or a built 700r4 will be better. This can be done later so you can save up, just don't expect the th350 to last under repeated towing and fast launches


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[Stewart G Griffin]

Not sure if you can tow 8000, run 13's, have 400hp and get acceptable mpg for $1500.

[roundhouse]

Best way to go is a crate motor from summit , jegs , or your GM dealer
It's cheaper than just the parts for building it yourself



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[sterlingbrum]

Not sure if you can tow 8000, run 13's, have 400hp and get acceptable mpg for $1500.

That's why I'm just trying to get an idea of what's needed, I was just trying to throw out some ideas so people know my intentions for this truck in the future

Best way to go is a crate motor from summit , jegs , or your GM dealer
It's cheaper than just the parts for building it yourself



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That's what the best idea is looking like so far, i guess I'd just upgrade it slowly. The worst part about that is I hate paying $1500 for a long block and the first thing I get rid of are the heads