Looking for 3873858 heads

[Joe R.]

While rebuilding the engine for my 66 BB, I found out that the heads are from '67. The block is numbers matching, so I would like to put the correct heads back on the motor. It is a May 66 car. Does anyone have any leads on these?

[Jay G.]

Re: Looking for 3873858 heads

Couple sets on eBay now. Do parts search for 3873858. Two diff. sets one with early May E 7 dates and one set April D 7 and E7 dates. Pricey but ret. port heads are.

[Joe L.]

Re: Looking for 3873858 heads

While rebuilding the engine for my 66 BB, I found out that the heads are from '67. The block is numbers matching, so I would like to put the correct heads back on the motor. It is a May 66 car. Does anyone have any leads on these?

Joe-----


Besides the apparently incorrect casting number on the heads you have, did you also confirm that the casting DATES are too late for your car?

[Joe R.]

Re: Looking for 3873858 heads

Yes, the part number for the head is have is a 67 casting number, the date codes are for after my car rolled off the line May 24, 1966.

I have been scanning ebay. I thought I needed heads one to three months older than the car. So, wouldn't a May head be too new?

Joe

[Jay G.]

Re: Looking for 3873858 heads

No you'd want heads "Before" the car was completed. Preferrably as close a possible. Joe is correct RE: 3873858 head casting are correct for Chevelles etc. Not Ret. Port Corvettes. (I have a 67 hevelle SS396 always looking at BB stuff) My 67 L79 Coupe is a survivor type car. One owner. All my Major compents heads trans, block, diff, intake, Ignition, alt, etc. fall within 1 week of each Or the Same Day. 2/20/67 Car build March 1st 67. So try to do a search to get the Correct heads anywhere from March 66 to mid May or so 66. Joe Lucia could chime in with correct casting nos and addtional info re dates. Have fun searchin.

[Joe R.]

Re: Looking for 3873858 heads

Everything I've seen online says that 3873858 is the correct casting number for a 66 Corvette big block engine. Do you have documentation that says otherwise? I have some books, but not with me.

Joe

[Wayne M.]

Re: Looking for 3873858 heads

Everything I've seen online says that 3873858 is the correct casting number for a 66 Corvette big block engine. Do you have documentation that says otherwise? I have some books, but not with me.

Joe

Joe R -- all have jumped in, assuming that your '66 big block is an L72 and not a L36 (you didn't say initially -- nor did you revise). Different head numbers for the oval port 390hp version.

Square port 3873858 heads were used on Chev Passenger, Chevelle and Corvettes, in the 1966 model year.

As others have pointed out, there's lots on eBay (there's a set (?) now dated late Feb & April) --- should be able to get nice tight date groupings if you want. Remember head dates are not flight judged.

[Joe R.]

Re: Looking for 3873858 heads

Wayne,

Sorry, I failed to mention that it's a L72 425 HP motor.

Joe

[Ridge K.]

Re: Looking for 3873858 heads

[Joe R.]

Re: Looking for 3873858 heads

Ridge,

Thanks for the eBay advice. You obviously have more experience with it than I do. I checked detailed feedback on the gentleman you mentioned, he does look worth avoiding.

I was planning to go to Corvettes at Carlisle, but alas my plans fell through.

Joe