Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!

Visual Difference (between 305 and 350)

Thread Tools
 
Search this Thread
 
Old 08-20-2007, 07:44 PM
  #1  
Junior Member
Thread Starter
 
Moonlight's Avatar
 
Join Date: Aug 2007
Location: B.C.
Posts: 40
Likes: 0
Received 0 Likes on 0 Posts
Car: 1991 Z28
Engine: 350 TPI
Transmission: 4l60e
Visual Difference (between 305 and 350)

I was just wondering if there was any visual difference between a 305 and a 350 engine or do they basicly look identicle?
Old 08-20-2007, 07:52 PM
  #2  
Supreme Member

iTrader: (14)
 
//<86TA>\\'s Avatar
 
Join Date: Aug 2006
Location: Central NJ
Posts: 12,652
Likes: 0
Received 46 Likes on 44 Posts
Car: 86 Trans Am, 92 Firebird
Engine: 408 sbc, 3.1L of raw power
Transmission: TKO600, T5
Axle/Gears: Moser 9", 3:70 trutac, 3:23 torsion
Re: Visual Difference (between 305 and 350)

the only real ways to tell is possibly the casting number, or pull a head off.

is this motor in a car? the vin will tell you what it SHOULD be
Old 08-20-2007, 08:13 PM
  #3  
Member
iTrader: (5)
 
RITTER's Avatar
 
Join Date: May 2005
Location: Mooresville, NC
Posts: 368
Likes: 0
Received 0 Likes on 0 Posts
Car: 1983 Buick Regal
Engine: 355
Transmission: TH350
Axle/Gears: 4.11
Re: Visual Difference (between 305 and 350)

Yeah besides looking up the casting number or the VIN number, there is really no way of telling. The engines are identicle.
Old 08-21-2007, 09:39 PM
  #4  
Senior Member

iTrader: (4)
 
djtricia's Avatar
 
Join Date: Feb 2005
Location: Portage, MI.
Posts: 593
Likes: 0
Received 0 Likes on 0 Posts
Car: 1986 Z-28
Engine: 350
Transmission: 700R4
Re: Visual Difference (between 305 and 350)

On the back of the engine just above where the tran bolts on will be a number cast in teh block. 5.0 is 305, 5.7 is 350. This is only on the newer engines I believe.
Old 08-25-2007, 05:55 PM
  #5  
Junior Member
 
third gen crazy's Avatar
 
Join Date: Aug 2007
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
Re: Visual Difference (between 305 and 350)

i have also heard that the harmonic balancer's are different sizes
Old 08-25-2007, 06:10 PM
  #6  
Member

 
facelessnumber's Avatar
 
Join Date: Jun 2006
Posts: 130
Likes: 0
Received 0 Likes on 0 Posts
Car: 91 RS
Engine: L03 carbed
Transmission: 700R4, rebuilt+kit
Axle/Gears: 3.42, posi, disc
Re: Visual Difference (between 305 and 350)

Originally Posted by third gen crazy
i have also heard that the harmonic balancer's are different sizes
From the factory perhaps, yes. But neither that nor the VIN is a reliable way to know unless you're 100% sure the engine has never been swapped. And if you knew that, you wouldn't be trying to find the displacement now... Look above the transmission bolts, cast on the back of the block on the driver's side.

If it's too hard to read the casting number, I believe someone on here once said you can park the car sideways on a 45 degree incline, then rotate the crankshaft until one of the pistons is at the absolute bottom of its stroke. Pull a sparkplug and fill that cylinder with oil. Measure the amount of oil. Multiply by 8.
Old 08-25-2007, 08:41 PM
  #7  
Supreme Member

 
Supervisor42's Avatar
 
Join Date: Jul 2005
Location: Arab, Alabama
Posts: 1,675
Likes: 0
Received 3 Likes on 3 Posts
Car: 1988 Trans Am GTA
Engine: 350 4BBL
Transmission: 700R4
Axle/Gears: 3.27
Re: Visual Difference (between 305 and 350)

Originally Posted by facelessnumber
...If it's too hard to read the casting number, I believe someone on here once said you can park the car sideways on a 45 degree incline, then rotate the crankshaft until one of the pistons is at the absolute bottom of its stroke. Pull a sparkplug and fill that cylinder with oil. Measure the amount of oil. Multiply by 8.
Thats ok, I think I could get motivated to read the casting number...
Old 08-25-2007, 09:35 PM
  #8  
Member

 
facelessnumber's Avatar
 
Join Date: Jun 2006
Posts: 130
Likes: 0
Received 0 Likes on 0 Posts
Car: 91 RS
Engine: L03 carbed
Transmission: 700R4, rebuilt+kit
Axle/Gears: 3.42, posi, disc
Re: Visual Difference (between 305 and 350)

Originally Posted by Supervisor42
Thats ok, I think I could get motivated to read the casting number...
Kinda my point. You gotta read that casting number.

Of course, there's a remote chance somebody changed the crank. You could be looking at a 327 stamped "5.7." (Or a 383 for that matter...)
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
xkingcodex
Engine Swap
14
02-12-2020 07:43 PM
Jake_92RS
Tech / General Engine
8
01-28-2020 10:37 PM
st.evel07
Engine Swap
5
08-13-2015 06:15 PM
Sanjay
Engine/Drivetrain/Suspension Parts for Sale
1
08-12-2015 03:41 PM



Quick Reply: Visual Difference (between 305 and 350)



All times are GMT -5. The time now is 08:37 AM.