Author Topic: Building a 305....on purpose.  (Read 2280 times)

Offline Eggman

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Building a 305....on purpose.
« on: June 02, 2018, 09:14:02 PM »
i recently bought a 7000 mile target master 305 from a corvette restoration business. Ive decided to put it in my 78 C10 rat rod. Ive bought a cam,lifters ,timing set ,valve springs,locks and retainers for it. The cam I chose was the venerable 204/214-.420/.442 grind but on a 110 lsa vs 112.The truck already has a Powertrax locker in the 8.5 rear with 3:42 gears and and a 2200 stall converter in a fresh 350 turbo trans. It’s got full length headers and 2.5 full exhaust,1406 carb,hei,and I’m using a Streetmaster intake good to 4500 or so.The reason for this engine swap is the 350 in the truck is very tired and I’m not sure how long it has left. Any guesses on how this baby small block will run?
« Last Edit: June 03, 2018, 06:42:26 AM by Eggman »

Online Rapid Roy

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Re: Building a 305....on purpose.
« Reply #1 on: June 02, 2018, 09:48:58 PM »
Welcome
1974 Cheyenne 10 LWB STOCK 350 W HEI /TH350/AC/4 BBL Quadrajet
Mopar by Birth
Chevy by Choice

Offline Stewart G Griffin

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Re: Building a 305....on purpose.
« Reply #2 on: June 04, 2018, 05:06:52 PM »
Are the heads stock?

i hope you........nevermind.......($$$).........

Offline FlatBlack77

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Re: Building a 305....on purpose.
« Reply #3 on: June 05, 2018, 08:26:01 PM »
it should run pretty good. make sure to run a decent quality ignition setup. Dont just slap the old used distributor in. it is probably just as tired as the engine
"When you are a hammer, everything looks like a nail"
'77 C/10 - 350/350 mild street motor

Offline DustyRusty

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Re: Building a 305....on purpose.
« Reply #4 on: June 11, 2018, 06:57:27 PM »
I've always been mildly interested in the 305.

Back in 1999 Marlan Davis of Hot Rod/Car Craft magazines wrote an article on a series of upgrades to the 305.  You might find it interesting:

      http://www.hotrod.com/articles/ccrp-9903-305-chevy-small-block-engine-build/

Rusty

1975 K-10 SWB Fleetside - 350/SM465/NP205/D44F 12-boltR, 3.73 gears.  Original owner.
Customized by rust.

Offline Ronno6

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Re: Building a 305....on purpose.
« Reply #5 on: June 25, 2018, 03:40:23 PM »
Good to hear!
I have been pondering whether to upgrade my 305 or replace with a 350.
My engine is newer than the truck, as the C10 is an 84 but the motor has a 1 piece rear main.
I have been reading about head,cam,exhaust and intake mods to perk the 5.0 up to 350hp or so, and may pursue that route.
I already have the Hedman long tube headers.
I'll be checking on your thread to see how things are working out.
You can lead a man to water, but yoiu can't keep him from pissing in it.

Offline 75gmck25

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Re: Building a 305....on purpose.
« Reply #6 on: June 27, 2018, 06:44:53 AM »
It always helps to do a little long term planning first.   

The changes you are planning are good choices, but it won't be easy to go beyond that level without upgrading heads.  Replacing heads is a little more complicated upgrade, but it lays the foundation for much better overall performance.    Iron Vortec heads or low budget aluminum heads could add at least 40-50 hp to the combination you have.  It will really wake up that cam if your carburetor can provide the flow. 

The 1406 is an economy carburetor, and it will require retuning to go along with your other changes.   You can make the 1406 work, but a Quadrajet or Holley would be a better choice if you can get one at a reasonable price.  It would be easier to measure the effect of carburetor changes if you first install a wideband AFR.

Bruce

Offline Eggman

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Re: Building a 305....on purpose.
« Reply #7 on: July 15, 2018, 10:04:15 AM »
So,its up and running! I had the heads gone over at a machine shop consisting of a 5 angle valve job,positive seals and port cleanup/deburring. Truck runs fantastic! The only thing i did different was i reused the performer intake off the 350 sans the streetmaster. And i used a new HEI with an adjustable vac advance. For a 305 its got plenty of pep and makes a great cruiser 8)