1966 Corvette VIN/Head I.D.

[Bob A.]

Your help would be greatly appreciated in identifying the "Heads" on this 1966 427 with VIN # 194676S115077. The "Heads" have the following markings: L128 GM1 CFD HI PERF 14096188

What markings should the correct "Heads" have?

Also, the 14096188 "Heads" have a tapered spark plug seat. The plugs I removed were AC R45TS. What AC Plug should be used with these "Heads"?

Many Thanks and Best Wishes!

Bob Adams

[Joe L.]

Re: 1966 Corvette VIN/Head I.D.

Your help would be greatly appreciated in identifying the "Heads" on this 1966 427 with VIN # 194676S115077. The "Heads" have the following markings: L128 GM1 CFD HI PERF 14096188

What markings should the correct "Heads" have?

Also, the 14096188 "Heads" have a tapered spark plug seat. The plugs I removed were AC R45TS. What AC Plug should be used with these "Heads"?

Many Thanks and Best Wishes!

Bob Adams

Bob----

The GM casting #14096188 was one of two castings used for the GM part #6260482 cylinder head (the other was GM casting #6272990). The GM #6260482 cylinder head was a SERVICE replacement cylinder head for all 65-69 Corvette applications with SHP engines and rectangular port heads.

From a performance perspective, the 6260482 was superior to any of its predecessors. Except for the plugs, it is generally externally configured like most of the 66-69 cast iron heads, but there are a few other differences.

The 6260482 was the last cast iron head available from GM for Mark IV big blocks. It was discontinued several years ago, though.

The 14096188 casting did not come into use until the early 80's. So, the dates on your heads must be December 12, 1988 or December 12, 1998. The heads were out-of-production by 2008.

As far as plugs go, you could use any T or TS suffix plug with a heat range equivalent to the that originally used for your application. I would say that an R44T or TS (extended tip) would be about right. I don't think that tapered seat plugs are available from AC in a non-resistor type, so you will need to use resistor plugs. No problem, though.

[Bob A.]

Re: 1966 Corvette VIN/Head I.D.

Joe:

Many Thanks for your prompt, detailed, and valuable, information. It is greatly appreciated.

To make this engine correct and numbers matching, what would be the correct heads? Are they available? What would be a ball park price to pay? Would the #14096188 heads devalue the car appreciably?

Best Wishes!

Bob Adams

[Joe R.]

Re: 1966 Corvette VIN/Head I.D.

Bob,

I'm inferring from the previous posts that you have the L-72 (425 hp) engine. Assuming that's correct, the head part number you're looking for is:

3873858

I checked on eBay, there's some for sale on there. Check this one out for starters:

http://cgi.ebay.com/ebaymotors/66-Corvette-858-BIG-BLOCK-HEADS-3873858-427-435-400-3x2_W0QQcmdZViewItemQQhashZitem1c080b75f3QQitemZ120394053107QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

Joe