Author Topic: 305  (Read 18578 times)

Offline Stewart G Griffin

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Re: 305
« Reply #15 on: September 07, 2009, 09:45:14 AM »
The best advice I can give, is find one that can be rebuilt. Its kinda hard to tell the condition of an engine from the outside, but regaurdless, Id plan on rebuilding it. I can tell you the number of late model camaros and firebirds Ive seen lately that are smoking. I can find them running around here for $200-$300 dollars, but wouldnt put one in until I rebuilt it. Its too much trouble to put one in just to have to pull it out because it smoke like a freighttrain. Unless you can see it run before you buy it and verify that is runs good, rebuild it. These engines a cheap to rebuild if you want just a basic, good running, reliable engine.

Amen to that.   In fact, this is my new strategy;  (had time to think)

Offline malibu795

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Re: 305
« Reply #16 on: September 15, 2009, 08:53:49 PM »
350 vs 305..

at the time i built/re-built in stage my sbc 305..

first problem i found Camshaft 4 of 16 lobe were round/flat.. in went a 214/224* @.050 form summit. stock cam is les then .300" lift at the valve and sub 180* @.050" duration  :o
next heads. OEM stink!!! i picked up soem world castign SR torquer heads wiht 1.94/1.5 vlvs and 170cc runners  stock were 1.6-1.7 intake and 1.4-1.5 exhaust. wiht ~140cc runners both runs 58cc chambers
couple with the heads no wonder why they were gutless.... ::)
with that and a dual plane intake, new rings, beaings, o/p cab, headers i went from~140hp factory rated.to ~250-275hp.
with a 600cfm carb 7000rpm was not. a problem


my 305 is my back up motor. its gettin ready to get bored, honed, deck and new pistons..

nice note.. everything you buy for the 305 will cross over to the 350.. jsut be mindfull of the 58cc chambers. and the c/r ratio.
adam wildman
75 K25 383/400
79 malibu 454/T56 305rwhp/432rwtq 15.6@92.8mph
02 2500HD D-max/allison best time 13.77 @ 99mph 463rwhp/930rwtq

Offline Stewart G Griffin

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Re: 305
« Reply #17 on: September 16, 2009, 12:03:47 PM »
the cranks are not compatible, but i get the gist of what you're saying.

Offline malibu795

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Re: 305
« Reply #18 on: September 16, 2009, 02:23:04 PM »
who gave you that line of BS?

all SBC are interchangeable as long as both cranks either 1 peice rear main or 2-peice rear main.

there are adapters out there to put 1 peice mains in a 2 peice block. then the only difference is the FW bolt pattern 1 peice runs a smaller pattern then a 2 peice.
adam wildman
75 K25 383/400
79 malibu 454/T56 305rwhp/432rwtq 15.6@92.8mph
02 2500HD D-max/allison best time 13.77 @ 99mph 463rwhp/930rwtq

Offline Stewart G Griffin

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Re: 305
« Reply #19 on: September 17, 2009, 09:25:53 AM »
Well, the cranks are balanced differently because the 350's pistons are larger diameter than the 305's.

i'll try to dig up the link.   i mean, technically you could use the crank out of the different engine, but it will shake bad.

Offline malibu795

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Re: 305
« Reply #20 on: September 17, 2009, 09:31:01 PM »
Well, the cranks are balanced differently because the 350's pistons are larger diameter than the 305's.

i'll try to dig up the link.   i mean, technically you could use the crank out of the different engine, but it will shake bad.
yes you are right...  here the thing tho....
you change piston on the same engine and you can get a bad vibration.

for 150-200.. to get you rotating assemble balanced... is good money well spent... increase power, and service life greatly. smoother runnign engine less were and tear on other components etc......

FWIW OEm spec are balances +/-20-30grams...  machine shop is +/-2 grams
adam wildman
75 K25 383/400
79 malibu 454/T56 305rwhp/432rwtq 15.6@92.8mph
02 2500HD D-max/allison best time 13.77 @ 99mph 463rwhp/930rwtq

Offline jimbo

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Re: 305
« Reply #21 on: December 03, 2009, 10:11:49 PM »
I agree.  If the 305 is coming out then you are halfway to a 350 swap.  The only reason I ever modded a 305 for power was because it ran fine and we didn't have any reason to pull it.

Offline jimbo

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Re: 305
« Reply #22 on: December 04, 2009, 04:00:12 PM »
You know, after saying that, I should add that I actually do have a little budget shopping list (summit racing) for my 305 truck.

Intake - $99.50
http://www.summitracing.com/parts/XYZ-PC22001/

Cam kit - $89.95
http://www.summitracing.com/parts/SUM-K1100/

Headers - $89.85
http://www.summitracing.com/parts/SUM-G9006/


For less than $500, I figure I can have all this on the truck and hopefully drastically improve my power and give me a few more mpg's while I'm at it.  I hope to get well into the 200hp range with a really healthy low rpm torque curve.  After that, replacing those ridiculously high 2.79 rear gears.


Offline VileZambonie

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Re: 305
« Reply #23 on: December 04, 2009, 04:38:46 PM »
Jimbo, why do you want to change the cam? That cam has slightly less lift than the stock cam.
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline jimbo

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Re: 305
« Reply #24 on: December 04, 2009, 04:56:07 PM »
Jimbo, why do you want to change the cam? That cam has slightly less lift than the stock cam.

I honestly don't know the specs on the stock cam, I just remember how much better my last 305 ran with a small summit cam.  I just priced summit's level "0" (1100) cam kit, not wanting to get something that would react poorly with the stock converter and highway gears, not to mention small cubic inches and my heavy truck.


Cam 1101 is the next step up I was considering, and I haven't truly researched and chosen one yet, as I am going to do all this after the new year.
http://www.summitracing.com/parts/SUM-K1101/

Cam 1102 seemed too large for my simple truck, especially since I am hoping to improve mpg's.
http://www.summitracing.com/parts/SUM-K1102/


What do you think, Vile?

Offline VileZambonie

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Re: 305
« Reply #25 on: December 04, 2009, 05:53:06 PM »
Go with the 1102
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              ⌠ŻŻŻŻŻ'   [☼===☼]
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline jimbo

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Re: 305
« Reply #26 on: December 04, 2009, 06:08:33 PM »
Go with the 1102

Cool, thanks for the advice.  I seem to remember stock 350 cams being around the 400in/415ex range, but I'm sure that was on a bigger lsa cam.  I was thinking about going somewhere in that zone to stay nice and drivable, as I have experienced the result of overcammined many of my toy cars in the past, haha.  If you think the 0.420 int./0.442 exh. cam would work well, I will probably definitely pick that one up.

Offline jimbo

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Re: 305
« Reply #27 on: December 04, 2009, 06:17:19 PM »
Just for discussion sake here are the next few camshafts in that line:

http://www.summitracing.com/parts/SUM-K1103/

http://www.summitracing.com/parts/SUM-K1104/

http://www.summitracing.com/parts/SUM-K1105/

http://www.summitracing.com/parts/SUM-K1106/


Again, thanks for the help.  My last small block I built was a ford 308 and I had a solid lift .560 cam in it that made power at 7k, so its been a while since I have picked out a cam for a stock style vehicle that will be towing.

Offline VileZambonie

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Re: 305
« Reply #28 on: December 04, 2009, 09:27:39 PM »
For your 305 the 1102 is your best bet.
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                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline malibu795

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Re: 305
« Reply #29 on: December 05, 2009, 01:00:08 AM »
For your 305 the 1102 is your best bet.

i have ran the 1102 with 1.6 rockers.. it is a fun cam to drive.. in my 305.

IMO lift the heads and put a shim head gaskets inthere to gain some compression bought .5 of a points... stock is very low 8:1 on the older 305s
similar to this
http://www.summitracing.com/parts/FEL-7733SH1/

this setup you ccan use stock push rods as well
as for springs K-motion 700 will drop in (same 1.25" dia stock is) and handle .550 lift and alow you to use stock install hieght of 1.700"
springs and no need for machining the heads for springs
http://www.summitracing.com/parts/KMO-K-700/ 48.00
retainers 7* (reuse stock 7* locks or IMO upgrade to 10*
http://www.summitracing.com/parts/KMO-K-7420/ 65.00
10* reatainers
http://www.summitracing.com/parts/KMO-K-7500/ 65.00
10* locks
http://www.summitracing.com/parts/KMO-K-6110/

i dis like valve float.. not saying you will turn it that high.. i know that camshaft 1102 is capable of pulling to 6500rpm on a 305

good luck
adam wildman
75 K25 383/400
79 malibu 454/T56 305rwhp/432rwtq 15.6@92.8mph
02 2500HD D-max/allison best time 13.77 @ 99mph 463rwhp/930rwtq