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BILT4ME · 01-05-2017, 05:11 PM

I had a 69 K10 with a manual transmission (SM465) and 4.11 gears, 33x12.50x15 MT tires on steelies

The engine:
350, bored 0.060" over (=360)
Weiand 180* dual plane intake
Holley 650 Double pumper
Cam was Crane 113901 for towing, off road, and low-end torque
Pistons were 8.5:1 compression flat top.
Heads: 1.92 Truck heads ported, polished, and gasket holes matched
Exhaust Manifolds: rams horn cast iron manifolds (also ported, polished and matched)
Exhaust was 2-1/2" duals with DynoMax turbo mufflers

The engine was ported, polished, and balanced to 10,000 RPM. It was VERY smooth running.

I was pulling around 350 HP and this truck did VERY well for towing and would get no less than 12 MPG no matter what I was pulling. On the open highway, treating it nice, I would get 14 MPG.

Over time, I did a rebuild and the machine shop junked my heads, so I installed a set of STOCK (not ported, polished or matched) 1.92 truck heads. I lost at least 75 HP, the truck dropped to 8-10 MPG, and the carb was way over-jetted. I was starting a family so I sold it.

Anyway, the biggest difference you have here is that if you are actually at 10 or 10.5:1 compression, you COULD install a less radical cam, but you will have to run premium or above fuel. I agree that the engine the way it is currently set up would not be much fun to drive unless it is at WOT.

I set up my truck for driving and being a workhorse and it did that VERY well.

Good luck! I was first thinking a simple cam swap until I read the compression ratio. that combination would push me more toward one of the crate engines. Make sure you get it cammed appropriately for an automatic or manual transmission. (It can affect shift points)

http://www.cranecams.com/56-67.pdf

01-05-2017, 05:11 PM	#29
BILT4ME Registered User Join Date: Jul 2016 Location: Olathe, KS Posts: 267	Re: Lets talk Small Block I had a 69 K10 with a manual transmission (SM465) and 4.11 gears, 33x12.50x15 MT tires on steelies The engine: 350, bored 0.060" over (=360) Weiand 180* dual plane intake Holley 650 Double pumper Cam was Crane 113901 for towing, off road, and low-end torque Pistons were 8.5:1 compression flat top. Heads: 1.92 Truck heads ported, polished, and gasket holes matched Exhaust Manifolds: rams horn cast iron manifolds (also ported, polished and matched) Exhaust was 2-1/2" duals with DynoMax turbo mufflers The engine was ported, polished, and balanced to 10,000 RPM. It was VERY smooth running. I was pulling around 350 HP and this truck did VERY well for towing and would get no less than 12 MPG no matter what I was pulling. On the open highway, treating it nice, I would get 14 MPG. Over time, I did a rebuild and the machine shop junked my heads, so I installed a set of STOCK (not ported, polished or matched) 1.92 truck heads. I lost at least 75 HP, the truck dropped to 8-10 MPG, and the carb was way over-jetted. I was starting a family so I sold it. Anyway, the biggest difference you have here is that if you are actually at 10 or 10.5:1 compression, you COULD install a less radical cam, but you will have to run premium or above fuel. I agree that the engine the way it is currently set up would not be much fun to drive unless it is at WOT. I set up my truck for driving and being a workhorse and it did that VERY well. Good luck! I was first thinking a simple cam swap until I read the compression ratio. that combination would push me more toward one of the crate engines. Make sure you get it cammed appropriately for an automatic or manual transmission. (It can affect shift points) http://www.cranecams.com/56-67.pdf __________________ 1970 GMC K2500 Dis-use is harder on a car than mis-use.