Time to start!

[78BO]

Hello people.

Looks like it's time to start buying parts for my engine. I have a feeling that what I'm gona ask has been asked before, but there are so many threads I can't tell. SO!

I've got a 78 SWB Heavy Half with a 350. I want 400hp. Would like 400whp.
My questions will start with, did these come with steal cranks or cast? Are the heads worth the work to build or would it be better to buy built heads? What would be the best cam (or cam/head combo). I'm a pretty good with this stuff, but this will be my first build. I haven't tore it down yet, I wanted to as much info before I get into it.

Any info would be great.

[Captkaos]

Cast Cranks
Stock heads are Junk for what you want
Cam needs to be selected based on the rest of your combination, you need to Plan the engine as a unit, not throw pieces at it.

For 400RWHP, you need 500hp at the crank.
Cheapest route is a 6.0L LS motor swap.
see here, links at the bottom take you through all of their stages..
http://www.hotrod.com/techarticles/e...ock/index.html

[chrismoore701]

I am doing the same thing with my '79, but I want 420 hp. I have a 350 4 bolt and plan to make it into a 383 stroker and buy all new componants and try to get some good 202 heads. Not going to start this for a good while.

Chris

[78BO]

I don't want to swap engines. I want to try an keep what it came with. I know you have to match things. Heads/cam/carb. The reason I asked about the crank is so I can start looking for a better one if I need to. I know I'll need to raise the compresion, I just don't know by what. I also know that you don't loose 100hp through the drive train. It's more like 20-30%, depending on the rest of the drive train. So 450 would (should) be real close to my target.

I guess I'm just wanting some input from guys that have already done what I'm doing. But thanks for the info.

[Albatrossian]

How much are you wanting to spend? 500hp at the crank with a non-LS motor will have a lumpy cam unless you plan on going roller. You'll need at least a good, ported set of 2.02 heads. 4-bolt mains preferably, a good set of headers/mufflers/mandrel-bent exhaust. Plus a torque converter to match the cam you're going with so you can get all that power to the ground. It takes a bit of planning, but it can be done pretty easily.

[Albatrossian]

I've done what you're doing.. with the cam/heads/pistons/intake/carb, I'm putting out 400+ at the crank according to DD2000.

[Captkaos]

You generally loose 70hp from a TH350, 80hp from a TH400, and about 50 through a manual, you also loose power through the ring gear/pinion and any engine accessories. Typically these will be left off during an engine dyno to get crank power.

I can agree on an average of 20-40% loss from end to end. With 500hp, that is a loss of 100hp, with 450hp, that is a loss of 90 hp.

You can add more to the above number for a loose converter to plant all this power and allow you to launch it, in addition to steeper gears.

Are you going to be Drag racing this? Or street driven?

You ask about raising compression are you talking about raising the compression of the current motor, or building a motor with more?

I would opt for some non factory aluminum heads, forged pistons matched to achieve no more than about 10:1 if you plan to drive it on the street without octane boost, lower if you use cast heads and splayed 4 bolt mains a roller valvetrain, and an intake to match the rpm range.
You also need to determine WHERE in the Rpm range you plan to make all this power...

[78BO]

It's going to be both track and street. Not so much race, but it's going to hit the track a few times. LOL yea, I guess 30% is a lot. The last car I built was a 4banger and the drive train loss is only 20%.

I've got an idea of what I think I want to do, so we'll see.