Engine ID Suffixes....Question
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From: Tallahassee FL
Engine ID Suffixes....Question
I have just joined the forum, so if this question has already been addressed please bear with me. I have a 65 small block with the ID number T0309HCH. The casting number is 3858180 which is correct for the years 64-66. I know the T is for Tonowanda, and the 0309 is March 9th, but the code HCH is not listed in any of the sources I have researched. The closest thing I can find is the code HC, which is for a 327 250hp full size auto for the years 64 - 67. Can anyone help? Thanks in advance.
Rick
[Modified by 67beast, 4:38 PM 9/2/2003]
[Modified by 67beast, 4:39 PM 9/2/2003]
Rick
[Modified by 67beast, 4:38 PM 9/2/2003]
[Modified by 67beast, 4:39 PM 9/2/2003]
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Re: Engine ID Suffixes....Question (67beast)
the casting number is for a 327ci which is limited use
are you sure you are reading the ID number right are sure it is not HO which is 327/250 hp with an automatic
or it could be HQ a 327/250 with an automatic and ac :confused:
are you sure you are reading the ID number right are sure it is not HO which is 327/250 hp with an automatic
or it could be HQ a 327/250 with an automatic and ac :confused:
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From: Tallahassee FL
Re: Engine ID Suffixes....Question (keith67)
I am quite sure of the code. That is what is so baffling about it. It is very clear...T0309HCH. Do you know what the HCH stands for?
Thanks.
Thanks.
Melting Slicks
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Re: Engine ID Suffixes....Question (67beast)
Welcome to the Forum... :seeya The "HCH" suffix was used for 1966 327 275hp Holley 4-bbl, powerglide applications in Passenger cars. :cheers:
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Re: Engine ID Suffixes....Question (67beast)
the second H stands for holley because the same engine with a rochester carb uses a R. the engine is a 1966 327 275 hp pass car :chevy
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From: Tallahassee FL
Re: Engine ID Suffixes....Question (clem zahrobsky)
Thanks to all, I appreciate the info. I suspected the motor was not original. It is in a 65 vette that I recently purchased, and it was obvious that it was rebuilt. The second H code is correct, it does have a Holley.
Thanks again to all.
[Modified by 67beast, 8:40 AM 9/3/2003]
Thanks again to all.
[Modified by 67beast, 8:40 AM 9/3/2003]
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Re: Engine ID Suffixes....Question (67beast)
No Tonawanda-assembled ("T" on the stamp pad) 327 was ever used in a Corvette, although an (unverified) small number of 8180 Tonawanda-CAST blocks were sent to Flint Engine and used during a brief foundry shutdown at Saginaw in 1965. These few engines have a "T" adjacent to the casting number, a two-digit year code on the casting date, but have the usual "F" (Flint Engine) prefix on the assembly stamping. :thumbs:
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Re: Engine ID Suffixes....Question (JohnZ)
One possibility here is if the engine was restamped they added that "3rd" character. This "3rd" appears on "Protecto Plates" and a lot of times people get this idea that this "3rd" character is "supposed" to be on the engine pad, when indeed, it's not. My '68 has the code "HT" for L79 327/350hp "on the engine", BUT the Protecto Plate says "HTR". The "3rd" character R in my case stands for "Rochester" for the Q-Jet that it has. This IS NOT uncommon to see this. I've seen it a good many times at Corvette shows and the like.
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From: Washington Michigan
Re: Engine ID Suffixes....Question (mogulmike)
Clem and Paul are both correct - the HCH and HCR suffixes WERE used just once, on '66 pass car engines; otherwise, the "H" and "R" third-digits were only used on the P-O-P codes. Other 3-digit suffixes on the stamp pad didn't start until 1970. :thumbs:
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From: Tallahassee FL
Re: Engine ID Suffixes....Question (JohnZ)
It is interesting that this engine came in a 1965 vette. Since the engine is from a 1966 car, it would seem obvious that it was a replacement. The questions that arise are:
Is there any chance this was the original engine? No, I seriously doubt it.
Was it a dealer replacement? Probably not, since replacement engines are coded differently from GM, correct?
Did the original engine blow up soon after purchase, or did the replacement occur years down the road? No way to know.
Since it is probably not the original engine these are moot points, but it is food for thought, anyway.
Again, thanks to all for your input.
:thumbs:
Is there any chance this was the original engine? No, I seriously doubt it.
Was it a dealer replacement? Probably not, since replacement engines are coded differently from GM, correct?
Did the original engine blow up soon after purchase, or did the replacement occur years down the road? No way to know.
Since it is probably not the original engine these are moot points, but it is food for thought, anyway.
Again, thanks to all for your input.
:thumbs:
Melting Slicks
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From: Aggieland TX
Re: Engine ID Suffixes....Question (67beast)
67beast
My 65 NOM came with a 66 block:
Engine Block 3858174 A186 F0I25HCH Pad Stamp
The heads (3884520) appear to be from a passenger car (the mechanic who tore it down said it had the "small" valves).
Interestingly, another forum member had one about 6 days later than this and it also had the HCH suffix code.
Mine is in pieces in the spare room; replaced with a GM 350 Crate recently.
Interesting that these HCH engines keep turning up in Corvettes. Probably the first thing available to replace a blown engine.
From one HCH to another,
DZ
:seeya
My 65 NOM came with a 66 block:
Engine Block 3858174 A186 F0I25HCH Pad Stamp
The heads (3884520) appear to be from a passenger car (the mechanic who tore it down said it had the "small" valves).
Interestingly, another forum member had one about 6 days later than this and it also had the HCH suffix code.
Mine is in pieces in the spare room; replaced with a GM 350 Crate recently.
Interesting that these HCH engines keep turning up in Corvettes. Probably the first thing available to replace a blown engine.
From one HCH to another,
DZ
:seeya
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From: Tallahassee FL
Re: Engine ID Suffixes....Question (DZVette)
DZ
Definitely interesting. Mine has the double hump heads and the original manifold, which means maybe the lower end let go at some point. Since yours had an "F" code for Flint instead of the "T" code, then yours might have been one that was used during the shutdown mentioned in a previous post. I can't help but wonder if maybe these engines got diverted briefly as replacement engines.
:thumbs:
Definitely interesting. Mine has the double hump heads and the original manifold, which means maybe the lower end let go at some point. Since yours had an "F" code for Flint instead of the "T" code, then yours might have been one that was used during the shutdown mentioned in a previous post. I can't help but wonder if maybe these engines got diverted briefly as replacement engines.
:thumbs:
