FGF Advertisement Sponsor

Forums

Previous Thread
Next Thread
Print Thread
Rate Thread
#284535 02/15/14 02:00 PM
Joined: Feb 2014
Posts: 12
N
Member
Member
N Offline
Joined: Feb 2014
Posts: 12
Have a 67 bird numbers on motor block left side of waterpump on block are 0176218 under them is YY is motor a 400, or 428, or 455,

Google AdSence Sponsor for FGF Forums
Joined: Jan 2010
Posts: 2,405
Likes: 1
B
Member
Member
B Offline
Joined: Jan 2010
Posts: 2,405
Likes: 1
428 has a 428 cast in the side of the block between the frost plugs.


Al
Joined: Feb 2013
Posts: 3,220
Senior Member
Senior Member
Joined: Feb 2013
Posts: 3,220
Originally Posted By NUBBIN
Have a 67 bird numbers on motor block left side of waterpump on block are 0176218 under them is YY is motor a 400, or 428, or 455,


You need to see what the casting date is. That is behind the distributer. There was. YY in 67 that was a 428 and a YY in 73 that was a 400 and a YY in 74 that was a 455 all automatics.

Joined: Jul 2003
Posts: 4,248
Likes: 14
Premium Member
Premium Member
Joined: Jul 2003
Posts: 4,248
Likes: 14
You need the casting number and two letter code to positively identify a motor. The casting number is on the rear passenger side of the motor below the back of the head (or for very early 67 and before, near the distributor)

http://www.teufert.net/pontiac/page2.htm

Joined: Feb 2014
Posts: 12
N
Member
Member
N Offline
Joined: Feb 2014
Posts: 12
pass/side has numbers on block below head 1026 out from that is letters D N drivers side has numbers H286 out from that is letter N has 6x on heads

Last edited by NUBBIN; 02/15/14 04:46 PM.
Joined: Jul 2003
Posts: 4,248
Likes: 14
Premium Member
Premium Member
Joined: Jul 2003
Posts: 4,248
Likes: 14
Check the casting number. It's hard to get to with the hood on unless you stick a camera back there and snap a photo.

Joined: Feb 2013
Posts: 3,220
Senior Member
Senior Member
Joined: Feb 2013
Posts: 3,220
Look at this page to find the location of the casting number.

http://www.teufert.net/identify/identify.htm

Joined: Feb 2014
Posts: 12
N
Member
Member
N Offline
Joined: Feb 2014
Posts: 12
what are the numbers for on pass/side back of motor down low,

Joined: Feb 2014
Posts: 12
N
Member
Member
N Offline
Joined: Feb 2014
Posts: 12
will take hood off to see numbers, thanks

Joined: May 2013
Posts: 148
Member
Member
Joined: May 2013
Posts: 148


67 400 4sp Auto Convertible
Joined: Jun 2011
Posts: 161
G
Member
Member
G Offline
Joined: Jun 2011
Posts: 161
Just use your cell phone and snap a pic.


1967 FB 400 4-speed A/C Tyrol Blue w/ Dark Blue
1967 GTO 400 AT A/C Gulf Turquoise w/ Black (dad's 1st car, my last car)
Joined: Feb 2014
Posts: 12
N
Member
Member
N Offline
Joined: Feb 2014
Posts: 12
It is 1973 400 yy

Joined: Feb 2014
Posts: 12
N
Member
Member
N Offline
Joined: Feb 2014
Posts: 12
it is 1973 400 YY found 400 on block, is this a good motor

Joined: Apr 2010
Posts: 6,758
G
FGF Premium Member
FGF Premium Member
G Offline
Joined: Apr 2010
Posts: 6,758
Year Engine HP Engine code Trans CR Cam Head Code BBL Carb No. Misc
1973 400 200/230 HP YY A 8.0 066 4X 1-4 7043262 Block Casting # 481988 Unitized Dist

http://www.wallaceracing.com


Engine Test Stand Playlist: https://www.youtube.com/playlist?list=PLwoxyUwptUcdqEb-o2ArqyiUaHW0G_C88
restoring my 1968 Firebird 400 HO convertible (Firedawg)
1965 Pontiac Catalina Safari Wagon 389 TriPower (Catwagon)
1999 JD AWS LX Lawn tractor 17hp (my daily driver)
2006 Sequoia
2017 Murano (wife's car)
202? Electric car
203? 68 Firebird /w electric engine
2007 Bayliner 175 runabout /w 3.0L Mercuiser__________________________________________________________
Joined: Feb 2014
Posts: 12
N
Member
Member
N Offline
Joined: Feb 2014
Posts: 12
I also found block casting code on back of motor right above oil filter that is 500557 can not see numbers at dist/pad, can this be a 76 not a 73 motor

Joined: Feb 2013
Posts: 3,220
Senior Member
Senior Member
Joined: Feb 2013
Posts: 3,220
Yep, It's a 76 185 hp. Not a very desirable block but as long as you do not race it it should be fine under 400 hp if you build it.

Joined: May 2013
Posts: 148
Member
Member
Joined: May 2013
Posts: 148
Join the club frown .... looking at comments on the web, certainly seems the 500557 aint the pick of the litter.


67 400 4sp Auto Convertible
Joined: Feb 2013
Posts: 1,015
Premium Member
Premium Member
Joined: Feb 2013
Posts: 1,015
Originally Posted By HaroldB
Yep, It's a 76 185 hp. Not a very desirable block but as long as you do not race it it should be fine under 400 hp if you build it.


My Sprint will beat that.



69 OHC ZH Sprint Hurst 3 Speed 3:55
OHC Forum http://sohcsix.yuku.com/
WANTED: 1969 OHC Sprint "H" Camshaft
Joined: Aug 2002
Posts: 7,495
Likes: 1
F
Premium Member
Premium Member
F Offline
Joined: Aug 2002
Posts: 7,495
Likes: 1
Your Sprint will probably beat alot of the V8s around.

Joined: Jul 2003
Posts: 4,248
Likes: 14
Premium Member
Premium Member
Joined: Jul 2003
Posts: 4,248
Likes: 14
The mid 70's blocks should be no problem for building a moderate horsepower motor, just not a race engine, from what I've read. The bigger issue might be the motor mount holes. They changed the motor mounts from two bolt to three bolt in 1970. The early 70's blocks have all five holes and some of the mid 70's blocks do to. But there are some mid 70's blocks with only the three holes so you need an adaptor to bolt it up to an FGF.

Joined: Apr 2000
Posts: 7,408
Power Member
Power Member
Joined: Apr 2000
Posts: 7,408
A 73 block will be just fine.

The nickle content (strength) was gradually lowered over time as HP numbers decreased. Rated at 185 HP, the block is not the reason its rated as such. The reason for HP ratings is mainly found in the heads with the secondary being the cam.

You could take a set of #16 1968 360 HP GTO heads (incidentally only 330 HP in a Firebird) with a cam swap and have a 360 HP block. The reason pre 71 blocks were so desirable was that the net HP ratings were usually (and actually) off by upwards of 25% , thus the increased nickle in the block to offer a "margin of erro.r"

Would a 73 block suffice at 400 plus HP? absolutely.


Si Vis Pacem Parabellum

1967 Starlight black PMD Engineering 400 Auto
1968 Alpine Blue 400 4 speed
1968 Verdoro Green 400 HO 4 speed
2013 1LE 2SS/RS Inferno Orange Camaro.
Joined: May 2001
Posts: 3,615
B
Premium Member
*****
Premium Member
*****
B Offline
Joined: May 2001
Posts: 3,615
Originally Posted By Banshee
A 73 block will be just fine.

The nickle content (strength) was gradually lowered over time as HP numbers decreased. Rated at 185 HP, the block is not the reason its rated as such. The reason for HP ratings is mainly found in the heads with the secondary being the cam.

You could take a set of #16 1968 360 HP GTO heads (incidentally only 330 HP in a Firebird) with a cam swap and have a 360 HP block. The reason pre 71 blocks were so desirable was that the net HP ratings were usually (and actually) off by upwards of 25% , thus the increased nickle in the block to offer a "margin of erro.r"

Would a 73 block suffice at 400 plus HP? absolutely.


Additionally, the 500557 block has lighter webbing between the cylinder banks... decreasing its strength. However, it is widely agreed that these blocks will easily support a 500HP street machine.

My 2 cents...

...and if anyone is interested, I have a 500557 block available.



I'm a hobbyist. Not a professional. Don't be hatin'!

Joined: Nov 2009
Posts: 5
J
Member
Member
J Offline
Joined: Nov 2009
Posts: 5
What is the date code on the block by the distributor?
It will look like something D126.

Also their is probably a partial VIN down lower on the block next to the timing cover.
See what that is also. It can tell you what the engine came out of.

smile


John Wallace
Pontiac Power RULES !!!
Wallace Racing
Joined: May 2014
Posts: 57
T
Member
Member
T Offline
Joined: May 2014
Posts: 57
This is what's in my 68...

Year Engine HP Engine code Trans CR Cam Head Code BBL Carb No. Misc
1967 400 265 HP YD A 10.5 254 143 1-2 7027061 A/C Block Casting # 9786133

What's the verdict on these?


68 400 4 spd Convertible
Joined: May 2015
Posts: 1
6
New Member
New Member
6 Offline
Joined: May 2015
Posts: 1
I have a 69 Firebird where the previous owner changed the engine. They put a 1976 400 in it. Has anyone else done this or heard of any one doing this and are you aware of any fit issues? Is the 76 Engine physically larger?

Joined: May 2013
Posts: 148
Member
Member
Joined: May 2013
Posts: 148
I have a 1976 (500557, date D056) in my 67 and it fits fine.


67 400 4sp Auto Convertible
Joined: Jan 2002
Posts: 7,719
Power Member
*****
Power Member
*****
Joined: Jan 2002
Posts: 7,719
All Pontiac V8 engines, with exception of the crappy 301, basically share the same engine block. Differences are crank journal and bore sizes.

Late 70's blocks do not have the motor mount holes tapped for 1st Gen Firebirds. They make adapter plates.


2012 Mustang Boss 302 #1918, Competition Orange. FGF replacement
2006 Mustang V6 Pony, Vista Blue. Factory ordered.
2019 BMW X3 (Titled to the wife, but I'm always driving it for her. So I'm claiming it)
Old projects, gone but not forgotten:
1967 FB 400, original CA car. After 22 years of work, trashed by the guy who was supposed to paint it. I had to sell it.
1980 Turbo Trans Am
1970 Mustang fastback, 351C 4Bbl, auto
1988 Mustang GT, 5 speed
1983 F-150 4x4, built 302
1994 Chevy K2500 HD 4x4, 454 TBI
Joined: Mar 2012
Posts: 1,529
Likes: 41
B
Member
Member
B Offline
Joined: Mar 2012
Posts: 1,529
Likes: 41
Put a 1977 557 block in a 67 bird using the adapter brackets they sell. One small snag was one of the bolt holes in the block was not drilled and tapped to attach the new adaptor.
I have my own way around using these adaptors that don't always work.


Pontiac power
Joined: Aug 2015
Posts: 13
W
Member
Member
W Offline
Joined: Aug 2015
Posts: 13
On the front I have 0276694 WT, On the back I have K208 and 9790071. From what I found its a 68 400 WT 360hp made on November 20 1968. Is that correct? I was told it possibly came out of a GTO.

Joined: May 2008
Posts: 2,113
Likes: 1
W
Premium Member
Premium Member
W Offline
Joined: May 2008
Posts: 2,113
Likes: 1
K should be October they skipped I. So, October 20, 1968. I'm seeing that it could be a 350 HP GTO engine as opposed to the 360 hp. Either way, yes should have been out of a GTO.


1968 400 Coupe, verdoro green, black vinyl top, auto
1969 GTO Judge coupe, Carousel Red, manual
1971 Trans Am, cameo white, auto
1970 Buick Skylark Custom Convertible 350-4(driver), Fire Red, white top, auto
1972 Buick GS Stage 1, Royal Blue, black vinyl top, auto
Joined: Jun 2008
Posts: 69
Member
Member
Joined: Jun 2008
Posts: 69
Can anyone tell me what E075 means? I got that block sold as a 400. But the E seems to me, it's a 76' 350!

Edited:

It's fine! The block has the number 500557, what means, it is a 400 from 76!

Last edited by Lemmi; 01/09/19 01:39 PM.

68 Firebird 350 convertible deluxe - 4 speed
65 Morris Cooper Race
97 Lotus Elise
07 Corvette C6 Z06
12 Land Rover Defender 110
Joined: Jul 2018
Posts: 244
Likes: 1
Member
Member
Joined: Jul 2018
Posts: 244
Likes: 1
In 1971 all manufacturers started making lower HP motors just by changing the heads, they increased the area above the pistons raising the cc numbers and that lowered compression ratios from 10.75-1 to 8-1 or so. They also ran lame cams unless you had a HO, trans am, etc.

You could easily make this motor scream by changing the heads and cam, just don't push it, unless you're balanced etc you shouldn't push any V8 past 5000 unless you have lots of cash to blow on another engine. You could easily get this motor in the 350-400hp range with tons of torque.

Joined: Oct 2020
Posts: 34
F
Member
Member
F Offline
Joined: Oct 2020
Posts: 34
Here’s what I went by
843275E7-48C6-452B-B203-72D92D448B8C.jpeg

Joined: Apr 2019
Posts: 37
J
Member
Member
J Offline
Joined: Apr 2019
Posts: 37
The actual motor size will be the same often done as many original engines were raced, blown up or just worn out over the years.


Moderated by  Geoff 

Link Copied to Clipboard
Forum Statistics
Forums57
Topics35,534
Posts298,851
Members8,862
Most Online19,810
Feb 1st, 2026
Who's Online Now
0 members (), 406 guests, and 84 robots.
Key: Admin, Global Mod, Mod
Newest Members
Fireball1955, zinger223, MB13, Drevard, LarryK
8,862 Registered Users
Top Posters(30 Days)
Geoff 3
LarryK 1
Gordy 1
Top Posters
Bjorn Sefeldt 20,054
Fbody69 14,265
Yellowbird 11,905
68tpls400 10,337
salmon38 7,719
Firebob 7,495
Banshee 7,408
Gus68 6,758
Today's Birthdays
There are no members with birthdays on this day.
Photo Gallery
My latest 67 vert project rust bucket
My latest 67 vert project rust bucket
by Firebob, December 22
My weekend warrior
My weekend warrior
by Two67Firebirds, August 1
Cool dragster
Cool dragster
by Gus68, March 26
67 at Warbird show
67 at Warbird show
by Revvingup, December 31
With the old hood on.
With the old hood on.
by Firebob, July 29
Forum Search
NOTE: Search FGF Forums functions differently than the Search found at the top
Powered by UBB.threads™ PHP Forum Software 8.0.0