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planning a 350 rebuild focusing on bottom end tq.

Those are all interesting but other than the last 383, they are all mid to high range motors. I think I'm just going to copy the gm 330hp/380tq motor..it will be a huge upgrade as is but ill go ahead and pull the valves and clean the casting and do a port Match with the intake. I'm used to running premium anyways so do you guys think if my compression landed in the upper 9s to low 10s I'd be ok?

Here is the cam ill use unless one could specify a better one for this application.
http://www.crateenginedepot.com/Camshaft-Hydraulic-Flat-24502476-P9775.aspx
Haven't decided on the intake yet but I'm thinking either the performer or the performer eps..I'm leaning to the eps, it produces its max tq at 3500 which is close to the Dyno sheet I posted earlier
 
Actually, they use that shaft in the whole humble pie build. They are making more 327 ftlbs at 2200 RPM with iron exhaust manifolds. Thats pretty good.
 
EPS is good for lowend. I prefer the RPM, seems to run better all around. Somewhere there is a test that show as ported stock intake is best below about 2500 rpms as far as torque.
 
Think it is in David Visards book "how to build horsepower" I think #1.
 
Little bit of an update... that .06 block was bored a bit loose and is just a bit rough for street use, so its goin back to its owner.

I had some time on sat afternoon and checked the compression on the motor in my k10 just to see how bad it is..well I got a supprise lol.. 150-160psi on all 8. I guess its just a dog due to the combination and tune..

I did come across a set of 062 vortec heads complete with rockers and valve covers. So im going to vat and check them out..if they are good ill order an intake and cam/lifters. I will prob replace the water pump and radiator, powersteering lines while im in there.
 
Be real careful with used Vortecs. I know from experience of friends looking for good ones that they are VERY often found cracked. Personally I don't know as I'd ever buy a used set, and I'm cheap.

Buying used means used springs (although Vortec are weak springs in the first place), block mating surface that likely needs trued, etc. Going to be dumping more money into them to make sure they are "right", just make sure the risk is mitigated by very good price.
 
Ya im going to have these magnafluxed before I do anything. Were do they usually crack? I had planned on buying new ones but for a hundred bucks total I figured it would be worth the risk.
 
I believe the cracks tend to radiate from the valve seats out.

Can probably google for images of vortec cracks. Luckily mine were new and didn't have to deal with it, buddy had to check out 3 or 4 sets before he found some that weren't cracked, and that was just a visual inspection.

$100 would be a pretty good deal I suspect. Maybe be into parts $100-200 for higher end stuff? Even going with ARP screw in studs wouldn't add a ton of cost. Not sure if high mile vortecs have problems with the press-in studs. I had one break, but I think that was an anamoly.
 
Ya since ill be using a mild cam and be a low rpm motor, ill just use new stock springs. The factory stamped rockers look fine so ill prob re-use them. I saw the motor these heads came off of and it was a very fresh looking motor. The mechanic said it had 150k on it when it lost a rod bearing..not sure why it lost the bearing. The motor was in a Tahoe I think he said and the lady that drove it like a little old lady. So ive got fairly high expectations for these heads
 
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Since I've been on quarters and looking at how cheap you can build a 383 for now days, I've really been toying around with building a 383 short block, using 193' heads, comp extreme 4x4 cam, edlebrock TBI intake, and some form of aftermarket EMS to run the TBI. I've emailed all the top cam manufacturers and so far only Howards has emailed me back. They suggested their 205/215 @.050 .420/.453 lift on a 112 LSA. I'll let you know what Crane/Crower/Comp/lunati/Doug Herbert suggest cam wise. And I think I'll just clean up the bowls and gasket match the int/ext on the 193's, that way you keep the high velocity for that brutal low end torque. Btw yes I've had way to much time on my hands lol.
 
I would suggest about the same cam (204 214 420 443 lift). Ran it in every truck sbc for along time. Smooth idle good tq.
 
If you piece together a roller a stock Lt1 roller cam works really good too.
 
Now with less resistance how much of a torque increase would you have going to a roller setup. Like I really wish someone could do a side by side comparison. Btw how do y'all like those world product S/R heads? I need to find a flow chart for the 193s so I can see their low lift numbers.
 
I don't think the resistance to rotation is nearly as big a difference as is how fast you can close and open the valves, and how long you can keep them open, without running into a bunch of overlap.

I wouldn't be surprised if some magazine has done a roller vs. flat comparison, but you'd have to find cams with identical specs, and being able to open the valves "better", not much point to making identical grinds.
 
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