still not sure if 305 or 350 - The 1947 - Present Chevrolet & GMC Truck Message Board Network

cyberpine · 04-23-2010, 03:27 PM

I have every reason to believe my engine the original 305.. But my mechanic keeps insisting that not the original engine on the truck and thinks it might be a 350.

I can't seem to find the stamp. The only stamp I see on the engine is this one.

Other pictures to the truck.
http://picasaweb.google.com/cyberpine/1987C10#

Right now it runs way strong, but seems to stall or flood going from 0 to 20. They've changed the TBI gasket and sealed any air intake leaks. changed the Gas pump and filter. He wants to pull the intake and TB.

RandyP · 04-23-2010, 03:50 PM

Pretty sure I see the oil fill on the right .... Tells me 305 just looking. But, I'm a worthless mechanic. I can tear stuff up like a pro though.

glock35ipsc · 04-23-2010, 04:17 PM

Look at the front of the engine, right under the front of the passenger side head. There is a pad there that should have a bunch of letters and numbers stamped there. What are they?

If there are no letters and numbers there, are there a bunch of semi-circular marks? Like ))))))))))

cyberpine · 04-23-2010, 05:31 PM

Front - as in closer to the front bumper? More visible from the top or the bottom?

Thanks.

glock35ipsc · 04-23-2010, 05:42 PM

Bumper?? Front of the engine - as in, the front of the engine.

White circle:

Goldfinger · 05-22-2010, 03:54 PM

one trick i learned. 305 has oil filler on the left 350 has it on the right.

USSkoval · 05-22-2010, 04:34 PM

Quote:

Originally Posted by Goldfinger

one trick i learned. 305 has oil filler on the left 350 has it on the right.

Except it's super easy to swap covers

73chevyman · 05-22-2010, 04:55 PM

i looked at your motor pics and I 90% sure it's the original motor possible 305 HO but it's a 350 just by looking at it also the numbers will be under you altinator.......my .02

bitchin85 · 05-23-2010, 12:34 AM

your timing tab is set a little off to the side. if it were a 305 it should be straight down behind the center of the water pump.. i think.. check this

http://www.mortec.com/location.htm

82chevy350 · 05-26-2010, 03:14 PM

since its a tbi its a 1 pc seal the new motors the 350s the dipstick is on the passenger side on the back of the motor on the lip by where the oil pressure line hooks up there should be a stamp of 5.0 or 5.7

54Caddy · 05-26-2010, 04:29 PM

Try the vin behind the driver side head. Itll be on the block where the transmission bolts up. You will see it. Give this webiste a look i use this site for all my casting numbers
mortec.com

Chevy623 · 05-27-2010, 02:33 AM

Get a better mechanic, he'll tell you lol.

texasfunk · 05-27-2010, 02:36 AM

what side is the dipstick on? if its on the passenger it will be a 305 unless its a newer vortec engine...

Stepsideride · 05-27-2010, 02:38 AM

Look on the block behind the driver side cylinder head there will be a number there...that is the casting number...look that number up and it will tell you what it is.

nico · 05-27-2010, 06:53 PM

Both 350's and 305"s can have the passenger dipstick... The real oddball is the service replacement block that has the holes to mount a dipstick on each side. One trick I have used in the past is looking at the rear-most exhaust bolt on the passenger side manifold. Most 80's GM have two holes behind the number 8 cylinder. Bolt through the forward hole means 305, rear hole means 350.

If that fails, check the cast-in numbers behind the driver-side head. That is the casting number which most books refer to. The last three digits of that number will often be cast in the walls of the block, between the freezeplugs.

You can also pull a valvecover and check the casting numbers between the rocker arms. Very few people put the 305 heads on the 350's anymore looking for more compression.

If that fails, pull a head... 4" bore means 350, approx 3 3/4" bore means 305 and you are 1/3 of the way towards pulling the entire 305 out and selling it for $30 scrap iron.

USSkoval · 05-27-2010, 07:53 PM

Quote:

Originally Posted by texasfunk

what side is the dipstick on? if its on the passenger it will be a 305 unless its a newer vortec engine...

All SBC's from '80-up have the passenger dipstick

bitchin85 · 05-27-2010, 08:20 PM

Quote:

Originally Posted by USSkoval

All SBC's from '80-up have the passenger dipstick

true.. my 83 has a passenger dipstick and my 70s has it on the drivers side.. i know for sure both are 350s

04-23-2010, 03:27 PM	#1
cyberpine Registered User Join Date: Jul 2009 Location: Miami, FL Posts: 85	still not sure if 305 or 350 I have every reason to believe my engine the original 305.. But my mechanic keeps insisting that not the original engine on the truck and thinks it might be a 350. I can't seem to find the stamp. The only stamp I see on the engine is this one. Other pictures to the truck. http://picasaweb.google.com/cyberpine/1987C10# Right now it runs way strong, but seems to stall or flood going from 0 to 20. They've changed the TBI gasket and sealed any air intake leaks. changed the Gas pump and filter. He wants to pull the intake and TB. __________________ ----------------- JC (Cyberpine) My 1987 C10 Short Bed (click on slideshow to see full album)

04-23-2010, 03:50 PM	#2
RandyP Getting Old; Going Broke Join Date: Apr 2010 Location: Owasso OK Posts: 2,764	Re: still not sure if 305 of 350 Pretty sure I see the oil fill on the right .... Tells me 305 just looking. But, I'm a worthless mechanic. I can tear stuff up like a pro though. __________________ *Why is every used 350 sbc out of a corvette?* There's only two things that excite a man, expensive toys and real expensive toys. *VEGETARIAN: That's an old Indian word meaning "I don't hunt so good."* When the going gets tough, switch to power tools.

04-23-2010, 04:17 PM	#3
glock35ipsc Next project: 1970 K10 Join Date: Feb 2004 Location: Fort Collins, Colo 80524 Posts: 6,685	Re: still not sure if 305 of 350 Look at the front of the engine, right under the front of the passenger side head. There is a pad there that should have a bunch of letters and numbers stamped there. What are they? If there are no letters and numbers there, are there a bunch of semi-circular marks? Like )))))))))) __________________ *Bob* 1970 Chevy K10 LWB "Goldie" 350/TH350 *next project!!* 1981 Chevy C10 LWB 355/TH350 - My son's truck LS SWAP FORUM! Tons of LS swap info here! PLEASE CLICK HERE TO SUPPORT THE GREATEST BOARD ON THE NET! CLICK HERE FOR THE FAQ INDEX by KRUE

04-23-2010, 05:31 PM	#4
cyberpine Registered User Join Date: Jul 2009 Location: Miami, FL Posts: 85	Re: still not sure if 305 or 350 Front - as in closer to the front bumper? More visible from the top or the bottom? Thanks. __________________ ----------------- JC (Cyberpine) My 1987 C10 Short Bed (click on slideshow to see full album)

04-23-2010, 05:42 PM	#5
glock35ipsc Next project: 1970 K10 Join Date: Feb 2004 Location: Fort Collins, Colo 80524 Posts: 6,685	Re: still not sure if 305 or 350 Bumper?? Front of the engine - as in, the front of the engine. White circle: __________________ *Bob* 1970 Chevy K10 LWB "Goldie" 350/TH350 *next project!!* 1981 Chevy C10 LWB 355/TH350 - My son's truck LS SWAP FORUM! Tons of LS swap info here! PLEASE CLICK HERE TO SUPPORT THE GREATEST BOARD ON THE NET! CLICK HERE FOR THE FAQ INDEX by KRUE

05-22-2010, 03:54 PM	#6
Goldfinger Registered User Join Date: May 2010 Location: laurel hill Fl Posts: 645	Re: still not sure if 305 or 350 one trick i learned. 305 has oil filler on the left 350 has it on the right. __________________ 1985 C10 Custom Deluxe LWB 305/700r4 [ Goldfinger ] 1999 k3500 crew cab dually 6.5tdi/4l80e

05-22-2010, 04:55 PM	#8
73chevyman Registered User Join Date: Nov 2008 Location: Lusby, MD Posts: 563	Re: still not sure if 305 or 350 i looked at your motor pics and I 90% sure it's the original motor possible 305 HO but it's a 350 just by looking at it also the numbers will be under you altinator.......my .02 __________________ http://67-72chevytrucks.com/vboard/group.php?groupid=37 73 C10 Fleetside If it ain't a Chevy it's foreign http://hotridesmag.com/

05-23-2010, 12:34 AM	#9
bitchin85 Registered User Join Date: Aug 2009 Location: Lambertville MI Posts: 962	Re: still not sure if 305 or 350 your timing tab is set a little off to the side. if it were a 305 it should be straight down behind the center of the water pump.. i think.. check this http://www.mortec.com/location.htm __________________ "I'll keep my guns, money, and freedom. You can keep the "change"

05-26-2010, 03:14 PM	#10
82chevy350 Registered User Join Date: Sep 2009 Location: Van Buren, AR Posts: 321	Re: still not sure if 305 or 350 since its a tbi its a 1 pc seal the new motors the 350s the dipstick is on the passenger side on the back of the motor on the lip by where the oil pressure line hooks up there should be a stamp of 5.0 or 5.7 __________________ Drive It Like Ya Stole It '82 Primer White c10 2wd LWB 350 sbc t350 (Hot Rod) '90 2wd LWB Silverado 350 tbi 700R4 (Daily Driver) '53 m38a1 Willys Jeep (Toy)

05-26-2010, 04:29 PM	#11
54Caddy GM Addicted Join Date: Jan 2009 Location: Visalia, Ca Posts: 2,294	Re: still not sure if 305 or 350 Try the vin behind the driver side head. Itll be on the block where the transmission bolts up. You will see it. Give this webiste a look i use this site for all my casting numbers mortec.com __________________ ..Mac’s Garage.. 73 GMC, 54 Caddy, 2010 Silverado, 68 C10 RIP DAd My 73 GMC Truck Build Pic 2010 Silverado 4/6 on 24s IG:MacsGarage Last edited by 54Caddy; 05-26-2010 at 04:30 PM.

05-27-2010, 02:33 AM	#12
Chevy623 Registered User Join Date: Jan 2010 Location: Jacksonville Florida Posts: 234	Re: still not sure if 305 or 350 Get a better mechanic, he'll tell you lol. __________________ Jesse.

05-27-2010, 02:36 AM	#13
texasfunk Registered User Join Date: Jun 2009 Location: Lubbock, TX Posts: 1,671	Re: still not sure if 305 or 350 what side is the dipstick on? if its on the passenger it will be a 305 unless its a newer vortec engine... __________________ 2006 GMC Sierra CCSB, 6.0 swap 2000 Chevy C3500 Crew Cab shortbed dually 1999 Chevy c2500 Crew Cab shortbed 1982 El Camino 350/350 1979 K5 2wd blazer bagged/bodied 1986 Monte Carlo SS 1991 Chevy CK SWB-67 clip and tailgate, bagged 350/700r4 1955 Chevy Bel Air 2014 Chevy Silverado ccsb

05-27-2010, 02:38 AM	#14
Stepsideride Registered User Join Date: Feb 2010 Location: Murfreesboro Tennessee Posts: 129	Re: still not sure if 305 or 350 Look on the block behind the driver side cylinder head there will be a number there...that is the casting number...look that number up and it will tell you what it is.

05-27-2010, 06:53 PM	#15
nico Registered User Join Date: Nov 2006 Location: Marietta, OK Posts: 153	Re: still not sure if 305 or 350 Both 350's and 305"s can have the passenger dipstick... The real oddball is the service replacement block that has the holes to mount a dipstick on each side. One trick I have used in the past is looking at the rear-most exhaust bolt on the passenger side manifold. Most 80's GM have two holes behind the number 8 cylinder. Bolt through the forward hole means 305, rear hole means 350. If that fails, check the cast-in numbers behind the driver-side head. That is the casting number which most books refer to. The last three digits of that number will often be cast in the walls of the block, between the freezeplugs. You can also pull a valvecover and check the casting numbers between the rocker arms. Very few people put the 305 heads on the 350's anymore looking for more compression. If that fails, pull a head... 4" bore means 350, approx 3 3/4" bore means 305 and you are 1/3 of the way towards pulling the entire 305 out and selling it for $30 scrap iron.

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