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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: jhiggin on March 01, 2016, 08:28:10 pm

Title: sbc build opinions
Post by: jhiggin on March 01, 2016, 08:28:10 pm
well I'm ready to build a small block for my 81 k20 with v4500, p208, and 4.10 on 35s. Its a daily driver with occasional towing. looking to be in the mid to upper 3s with torque and obviously stay carbureted. I'm looking for opinions on what y'all think i should build. I would like to do this for a for under $2,000 and I'm not afraid to use used parts. I'm thinking 350 but give me input on ci, crank, rods, pistons, cam, rockers and lifters, heads, intake, carb, headers. just any opinions on a reliable daily driver build with decent power output.
Title: Re: sbc build opinions
Post by: bd on March 01, 2016, 10:07:32 pm
http://forum.73-87chevytrucks.com/smforum/index.php?topic=26161.msg222728#msg222728

http://forum.73-87chevytrucks.com/smforum/index.php?topic=31379.0

http://forum.73-87chevytrucks.com/smforum/index.php?topic=29498.msg246835;topicseen#msg246835

http://forum.73-87chevytrucks.com/smforum/index.php?topic=32085.msg270444;topicseen#msg270444
Title: Re: sbc build opinions
Post by: rich weyand on March 02, 2016, 02:19:59 am
Yeah, get a brand new base-level 350/260 crate engine (GM #10067353).  (currently on sale for $1460 with free shipping at Jegs: http://www.jegs.com/i/Chevrolet+Performance/809/10067353/10002/-1)

Put an SMI Qjet on an Edelbrock 2101 or an Edelbrock 1406 on an Edelbrock 2701, and put on Hooker Headers (2452 for 2WD, 2453 for 4WD).

You can re-cam the 350 with a more modern cam with quicker ramps to get more power and/or torque, with a Comp Cams 12-300-4, 12-235-2, 12-231-2 cam or similar.  This will void your warranty, but the GM crate engines are pretty bulletproof anyway, and you are talking about a *build* after all.  For occasional towing, I would probably opt for the 12-300-4, which won't wind as tight but is a torque monster in the bottom end.

That's about all you need.  Within your budget, and you are looking at close to 300 hp and well over 400 ftlbs.
Title: Re: sbc build opinions
Post by: jhiggin on March 03, 2016, 05:51:26 am
Awesome. Thanks for the guidance. Is there a cam on the market that will get me in the ball park of these cams you've suggested but give me alittle more lope at idle. Seems comp escribes these listed as having smooth idle
Title: Re: sbc build opinions
Post by: rich weyand on March 03, 2016, 08:46:57 am
You don't want lope at idle.  Lope at idle means it doesn't want to run at low rpm.  This is a characteristic of an engine tuned for high-rpm horsepower, not torque.  Lope at idle means, since it doesn't want to run at low rpm, that torque in the bottom of the rpm range will suck.

I mean, it's cool and all, but it would mean that the engine is set up exactly wrong for your stated use.

Put Flowmaster 40s on it instead.  A smooth idle sounds cool, too, when it's unrestricted and got some meat in it.
Title: Re: sbc build opinions
Post by: jhiggin on March 04, 2016, 05:46:51 am
Is there any videos up of your truck running?
Title: Re: sbc build opinions
Post by: rich weyand on March 04, 2016, 01:51:07 pm
Try this: https://www.youtube.com/watch?v=P8w-DPV5_Xw&feature=youtu.be
Title: Re: sbc build opinions
Post by: Captain Swampy on March 04, 2016, 05:16:59 pm
Check out Lunati's Voodoo or Bootlegger series of camshafts.
Title: Re: sbc build opinions
Post by: philo_beddoe on March 06, 2016, 10:38:31 pm
This is your best option...

http://www.hotrod.com/how-to/engine/1506-you-wont-believe-this-traditional-chevy-engine-is-an-ls3/
Title: Re: sbc build opinions
Post by: travisr1988 on March 08, 2016, 03:11:06 pm
I used a lunati voodoo cam 60101, which I absolutely love on the street, although I too like that lopey idle. The bootlegger line ups smallest cam is too big for bottom end torque, stick with Rich's recommendations or similar like the lunati voodoo 60101.
Title: Re: sbc build opinions
Post by: Greybeard on March 11, 2016, 10:04:18 am
You can actually get a bit more aggressive grind if you use something like Rhoads lifters. They are true anti-pumpup lifters and bleed so fast at idle and low rpms the torque is not completely lost. However, roller lifters are all the rage these days because oil quality, although higher than it has ever been, is not well suited for flat tappet cams anymore. But these are two areas of great debate potential. That is not my intention here. I will say I have run Rhoads of one type or another since 1983 and love them. They have a nice solid lifter sound, an even tick-tick-tick just like solids at idle. Variable valve timing via oil pressure and time.