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Howdy All - just came into a nice 1972 240Z that currently has a Chevy 350 in it. Conversion already done, but I'd like to drop a few more HP into it. I have two questions - 

 

1) I'm thinking a 383 with 450-500 hp would be a nice match. Since it is already setup for Chevy, i'll stay that route. What are some of the other options I should consider that are popular?

 

2) Engine source. There are a TON of engine builders on the internet. I know that many of them use junk Chinese parts and it will probably grenade quickly. Are there any reputable chevy engine builders that folks on the forum have had good luck with?

 

Thanks for the help!!

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Anyone? Thought this would be pretty straight-forward!  From what I've read, mostly either 350's or 383's.  I talked to one builder down in AZ (found him on a post from www.chevyspeed/com), was thinking for my $10k budget, I could get a dart block 420 ci with 600 hp.  Tempting as that is, I can't imagine being able to get that kind of HP to even come close to hooking up - especially with 225 tires!

 

So, at some point, extra HP just has no use in a 24xx lb car. What is that optimal torque / hp configuration?  Seems that we want engines that will rev quickly (light flywheel?), be very responsive in the throttle, and have a relatively flat torque curve.  Not looking for 0-60 times, more 30-100 times (on track).

 

What y'all think??

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Not looking for 0-60 times, more 30-100 times (on track).

So you're building a drag race car?  You haven't said anything about engine management or or transmission or how often you'll race or what your budget is.  Those would help narrow things down.  As you said, the options are many.  

 

Just curious, which companies sell the engines with the "junk" parts?  

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So you're building a drag race car?  You haven't said anything about engine management or or transmission or how often you'll race or what your budget is.  Those would help narrow things down.  As you said, the options are many.  

 

Just curious, which companies sell the engines with the "junk" parts?  

 

Sounds more like a road racing application, 30mph to 100mph.

 

I would think your horsepower goals need to be very specific for the type/class of racing you want to do.  I've got 300hp and I am totally happy with that.  Others like to play with much more than that.

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Howdy All - just came into a nice 1972 240Z that currently has a Chevy 350 in it. Conversion already done, but I'd like to drop a few more HP into it. I have two questions - 
 
1) I'm thinking a 383 with 450-500 hp would be a nice match. Since it is already setup for Chevy, i'll stay that route. What are some of the other options I should consider that are popular?
 
2) Engine source. There are a TON of engine builders on the internet. I know that many of them use junk Chinese parts and it will probably grenade quickly. Are there any reputable chevy engine builders that folks on the forum have had good luck with?
 
Thanks for the help!!

 

Depends on what your budget and goals are.  Would not trust the cheaper engine builds.  They will get by with cast pistons and cast crankshaft.  Cheap.  Use a GM 350 block.  Depends on which engine block came in the car when you purchased it.  Take that block or one of same vintage, bore .030 over and clearance for 3.75" stoke crankshaft.  Install forged pistons, forged 6" connecting rods and can get by with cast steel 3.75" stroked crankshaft for a 383 cu in displacement.  The cylinder head, camshaft and intake system will be the real key to power.  The more attention to details, the higher the quality and performance.

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This question would have garnered more active response some 10 or 15 years ago.  Today most persons with interest in the classical (first-generation) SBC would build their own, working with a local machine shop.  Others would gravitate towards the LS-series.  For evidence, consider what's happened to the post-count in the respective forums in recent years.

 

For a person interested in a crate engine, two possibilities come to mind.  The first is buying directly from GM.  This won't be a "custom" engine, but the specifications are reliably known, and surprises should be few.  The second possibility is to consult with local drag-racing participants, for their views on the local engine-building scene.  They should have recommendations on reputable local builders.

 

What ails the presently-installed 350? Is it too stock, too tired, or otherwise failing?  There might be value in performing relative modest refurbishment, or replacement of a few readily-accessible components (intake manifold, cam and lifters, etc.), and thereby obtaining a comparatively large power increase with little cost outlay.

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I built my own 350 with the help of the local automotive machine shop. My friend bought a GM 290 HP 350 crate motor for his 66 Chevelle and another friend put the same motor in his 37 Terraplane. Both installs went well and are quite peppy. Both vehicles are street driven mostly.

chris

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