V8 Thoughts and Options

[fermenter]

Positve P's 283 post inspired me to share my daydreaming. SBC only at this point.Low cubes.
As well as hoping to buy an Astro/Safari I also hope to complete a V8 swap someday. Been wanting to build up an engine also.

Be nice to have the extra funds to set up TBI and Vortec heads. Wonder if that GMP kit has the upward or downward manifold, worth the trouble or just homebrew the egr?

Anyhow here is the fun stuff:
Displacements;
L99 4.3 liter SBC (Mini LT1) short block only so not to use reverse cooling heads.
283 Classic, allways wanted one, should out pull 4.3 V6 if Vortec headed.(V6 converter)
305 Skip the early bad heads and small cam, should be fine but boring.

302 Now here is the real fun! (I know, just build a 350 but I'm thinking smaller cubes here)
Take a '96 and up 350 Vortec (need external cooling bypass for most manifolds) and install reballanced crank and rods from L99 4.3 V8. The rods from that one have the correct length to allow use of 350 pistons. You can check me on this 350= 3.48 stroke and 5.7 rod, 4.3 liter = 3" stroke and PM 5.94 rod. .240" is the magic number! Imagine being able to build up a 302 having the piston options from the highest selection of pistons available just like the 350.

From my research you get the one pc rear main seal, windage tray, roller lifter set up for a roller cam. I'm fairly clear the 3" crank has the correct nose set up for the common ballancers.

When the economy pulls back up gas should go back up also so I would build a TBI set up for low end power but you all could build a screamer!

I'm leaning most to the 283 or 302.
Cheers!

P.S. the 4.3 liter L99 was found in Roadmasters and Caprice's.

[Gary]

Ideal connecting rod ratios is covered in this article.It is using a Mopar as a example,but the same principles apply to SBC's and does have ref info to SBC's.Interesting read.....:

http://victorylibrary.com/mopar/rod-tech-c.htm

[fermenter]

I added that to my favorites, thank you!

Interesting to see the Chevy 327 has favorable rod length/stroke and bore/stroke ratio both!

Acording to the rod/stroke ratio also the 302 I described would do better in the low end with smaller port heads.
Hmmmm...this combo should do better with TBI heads than a 305 would.

[Gary]

Throw out your bank account and buy a Dart Iron Eagle block with a 4.185 bore and a 4" stroke.That is a over square deal that won't quit. Yeah,don't forget the 6" rods with custom Wisco pistons.

[fermenter]

OMG.....The small block that thinks it's a big block!
That follows my thought of not doing the more popular 350 and 383.

So much for small cubes though..............

[fermenter]

Ideal connecting rod ratios is covered in this article.It is using a Mopar as a example,but the same principles apply to SBC's and does have ref info to SBC's.Interesting read.....:

http://victorylibrary.com/mopar/rod-tech-c.htm

The 307 has the same preferred rod length to stroke ratio as the 327 and still oversquare.

[Gary]

Consider this.The over square formula in a small c.i. engine works,but the power band makes usable power for the most part out of normally driven street rpm ranges.It is kind of like owning a pc of apple pie that is almost out of reach,so you only get to eat a small pc of it at a time and then you have to go to the very top to get it.

[fermenter]

Yes I have considered that! I agree!
Just thought I would print my thoughts for comment. Not many people build small cube V8's for just that reason. I think/hope I can be happy with the power of the 4.3 V6 in an astro. Now I like a firm shifting tranny, the sound and feel of a V8. Put a nice exhaust on the 4.3 and it sounds like a blimp : (

So considering (keeping TBI) changing to a small V8 there could be some low rpm losses from the 4.3 V6 such as loosing the offset rod (I think) ,long stroke and high rpm losses from loosing the big bore and vortec heads. (Six big cylinders vs Eight smaller cylinders)
I'm kinda jumping around in my subject matter here.
I'm still trying to think of a cheep way to keep Vortec heads and TBI with EGR on a V8 conversion.
I know from having full sized vans it takes so much power just to push these things into the air at 70 mph. Smaller engines may have very low vaccume under those conditions resulting in less than optimum fuel dispersion.
I'd love to know what kind of MPG the V8 club members are getting.

Back to bore and stroke,(and rod /stroke) for low rpm power and economy possibly best to worse in this order; 305, 307, 302. Not to mention going up in cubes from there.

I don't know how long this process is going to take for me, I wanted to trade my car out for something new for the Brewwife but she just lost her temp. job. Need to get all that settled than get an Astro/Safari.

Thanks and keep 'em comming!

[fermenter]

Gary: In addition the most likely swap I would do is a TBI 305 or 350 from a doner due to cost. I just like to be differant and love to dream though..............