400 id pad question

Posted By: max

400 id pad question - 02/21/12 06:08 PM

I picked up a 1977 400 and the pad is stamped.

7T400
E
3

I know the 7T is for 1977 Trenton and the "E" is for cast crank but what is the "3" for?

Now here's the strange part, the engine has never been apart and the carb is a 9103 which is a 1977 400 HP.

I thought I read somewhere that some HP engines were just stamped with a number 2 or 3 instead of HP.
Is there any truth to that?

Posted By: John_Kunkel

Re: 400 id pad question - 02/21/12 07:08 PM

The 3 is part of the build date, either the builder forgot to stamp the rest or it's lightly stamped and hard to see.

After 35 years it's not unusual to find parts that have been swapped, the original carb was probably replaced with whatever was available or the HP is lightly stamped.

Posted By: max

Re: 400 id pad question - 02/22/12 06:34 PM

Your probablly right on all of those accounts John. I just found it a bit strange after all these years that a non HP engine would end up with the same year HP carb.

Posted By: Jamey

Re: 400 id pad question - 02/22/12 09:27 PM

I thought the T stood for truck?

Posted By: JohnRR

Re: 400 id pad question - 02/22/12 09:39 PM

Quote:

I thought the T stood for truck?

you and a half million others ...

No it does not .

Posted By: John_Kunkel

Re: 400 id pad question - 02/22/12 10:27 PM

It does stand for truck if it's located after the displacement; example....7T400T

Posted By: max

Re: 400 id pad question - 02/23/12 01:20 AM

Ok, here's what I read although I'm not sure it applies to my engine.

http://www.440source.com/blockinfo.htm

Quote:

There is absolutely no physical difference between a block with an HP or HP2 stamp and one without.

All blocks were cast and machined at the foundry, and then assembled at Chrysler's 2.1 million square foot "Trenton" assembly plant in Trenton, Michigan. During assembly, if the engine was given high performance cam and valve springs, or in some cases other items that differed between HP and non-HP engines such as: six pack rods, carbs, etc., then the engines ID pad would be stamped with HP. All blocks originally came from the same place, and there is absolutely no difference in cylinder wall thickness, nickel content in the cast iron, strengthening ribs on side of the block by the freeze plugs (see below for the real story on this,) or any of the other myths you have heard. The number 2, which you may find after the HP, (or in the case of non HP blocks, you may find just a "2" by itself, usually in the lower right hand corner of the ID pad) refers to the shift during which the engine was assembled. In running a factory, one 24 hour day can be divided into three 8 hour shifts. The first shift was considered a "1" however to save time, Chrysler did not stamp a "1", they just left it blank. So an HP2 engine, only means that the engine happened to be assembled on the second shift. There is no advantage to an HP2 block over an HP. we have never seen an HP3, (or just a "3") although Chrysler does allow for it in their documentation, so let me know if you have one or have seen one. Also of note is that non-HP engines usually used the same heads, intake manifold, and many other parts, which is great since it makes it a lot easier to bring a non-HP engine up to the power levels of a factory HP and beyond. But unless you are doing an original restoration, don't worry about finding and/or paying extra for an HP block.

Posted By: JohnRR

Re: 400 id pad question - 02/23/12 04:14 AM

Quote:

Ok, here's what I read although I'm not sure it applies to my engine.

http://www.440source.com/blockinfo.htm

Quote:

There is absolutely no physical difference between a block with an HP or HP2 stamp and one without.

All blocks were cast and machined at the foundry, and then assembled at Chrysler's 2.1 million square foot "Trenton" assembly plant in Trenton, Michigan. During assembly, if the engine was given high performance cam and valve springs, or in some cases other items that differed between HP and non-HP engines such as: six pack rods, carbs, etc., then the engines ID pad would be stamped with HP. All blocks originally came from the same place, and there is absolutely no difference in cylinder wall thickness, nickel content in the cast iron, strengthening ribs on side of the block by the freeze plugs (see below for the real story on this,) or any of the other myths you have heard. The number 2, which you may find after the HP, (or in the case of non HP blocks, you may find just a "2" by itself, usually in the lower right hand corner of the ID pad) refers to the shift during which the engine was assembled. In running a factory, one 24 hour day can be divided into three 8 hour shifts. The first shift was considered a "1" however to save time, Chrysler did not stamp a "1", they just left it blank. So an HP2 engine, only means that the engine happened to be assembled on the second shift. There is no advantage to an HP2 block over an HP. we have never seen an HP3, (or just a "3") although Chrysler does allow for it in their documentation, so let me know if you have one or have seen one. Also of note is that non-HP engines usually used the same heads, intake manifold, and many other parts, which is great since it makes it a lot easier to bring a non-HP engine up to the power levels of a factory HP and beyond. But unless you are doing an original restoration, don't worry about finding and/or paying extra for an HP block.

3 without the HP means it was assembled on the 3rd shift , it's NOT an HP without the HP stamp. If you didn't buy the engine NEW and don't have documented proof of every second of it's life prior to your owning it you have nothing to prove , or disprove the carb is original.

That said , SO WHAT if it has the HP spec carb on it , it doesn't change the fact that it is nothing more than a low compression smog motor.

That said X2 , was there a 400 -4bbl that wasn't an HP ??? If not then it's an HP that was not stamped but it's still a low compression smog motor.

Posted By: max

Re: 400 id pad question - 02/24/12 06:58 PM

As usual it looks like I read it wrong.

Atleast everyone knows now that I don't read instructions when I work on project.