'65 Tonawanda block

[Gene M.]

Re: '65 Tonawanda block

Question: does this block have the machined access hole with a square plug in it just over where the timing cover mounts?

[Roy S.]

Re: '65 Tonawanda block

Joe, I think it is an original stamping just as Pat Boyd and others feel, I also think as an original stamping it was a 300HP powerglide build when it left GM's possession whether in a pickup, passenger car, or over the counter, with no VIN derivative on the pad it did not leave in a Corvette. I also think the fact it is dressed as high horse now is added lipstick. It appears to be a Tonawanda casting and machining for sure.

[Joe R.]

Re: '65 Tonawanda block

Roy,

Have no doubt it is original but the original question was about the broach marks and the poster got the answer as the quote broach marks were nothing but sanding marks. This block had a serious case of rust as evidenced by the pits that are present in the picture. No broach marks could live thru that severe case of rust.
I have no doubt that it was stamped at the plant where it was assembled.
Good to hear from you. Looks like I am going to attend the OK meeting one Saturday morning. Look forward to seeing all my friends in Tulsa.

Joe

[Steven B.]

Re: '65 Tonawanda block

I've been wrong before and I'm not a pad expert, but when I look closely at the O, I still see the right side as slightly rounded, and what appears to be the faint leftovers of the top and bottom legs of a C. I think that someone at some point, for whatever reason, very artfully connected the top and bottom of the C to create an O. As Wayne suggested, I don't know what the gain would be going from a 250 hp powerglide to a 300 hp powerglide (other than 50 hp and being stamped as a Tonawanda corvette engine), but I think that Patrick and Cecil may have been on the right track. I wouldn't have thought anything of it until they made their suggestions. Whatever it is, it is difficult to be absolutely certain, although the pictures are pretty good. I will however, defer to the experts, as I am not interested in starting an argument.

Steve

[Wayne G.]

Re: '65 Tonawanda block

Roy you are right on the 365hp intake, carb, fuel filter and exhaust manifolds. The lipstick. The car did start out life as a true 365hp car, but when the engine failed for what ever reason the Tonawanda engine was installed. Maybe just a coincident that it was an HO block. Also note the balancer is the small 250hp version and the dipstick is not chrome. As the heads are also '65 this must have been a complete long block that was installed. The engine has been in a heated shop for years, not much rust except the unpainted water pump.

Wayne

[Jim S.]

Re: '65 Tonawanda block

Question: does this block have the machined access hole with a square plug in it just over where the timing cover mounts?

This is what Gene is referring to. Without this on a Tonawanda block, it wasn't used in a Corvette in 1965.

[Terry M.]

Re: '65 Tonawanda block

This is what Gene is referring to. Without this on a Tonawanda block, it wasn't used in a Corvette in 1965.

Let me state right up front that I know nothing about mid-years.
That said, If I saw the above pictured plug on a 1968 to 1972 cylinder case I would conclude that it had been machined and assembled at Flint regardless of where the cylinder case was poured. In the 1968 to 1972 era we have several genuine examples of Corvette installed cylinder cases poured at Tonawanda, but machined and assembled in Flint. We cite this in the appropriate TIM&JG and there has been at least one article in [I]The Restorer[I/] fully explaining the subject. Based on the explanation of people at Flint engine and Saginaw Metal Casting I have always suspected that the practice of occasionally shipping cylinder cases from Tonawanda to Flint for machining and assembly went on long before 1968 and long after 1972.

[Mike M.]

Re: '65 Tonawanda block

just because that 1/4" pipe plug is present in a SBC case, doesn't mean the SBC block was cast in Michigan. I once judged a c-2with the plug but suspected it was a tonowanda block. I asked the owner if he'd remove the plug so I could determine if the passage was drilled thru into the oil passages . when he refused to remove the plug, we took the appropriate deduct for a "modified" tonowanda block. he did not protest too vehemently . there is definitely enough casting meet in the plug's normal location to drill and tap the area for a pipe plug. at least I'm told that's the case. the cheater block in the white 57 FI that was involved in the dipstick races of the early 90's was one such modified tonowanda block. mike

[Terry M.]

Re: '65 Tonawanda block

just because that 1/4" pipe plug is present in a SBC case, doesn't mean the SBC block was cast in Michigan. I once judged a c-2with the plug but suspected it was a tonowanda block. I asked the owner if he'd remove the plug so I could determine if the passage was drilled thru into the oil passages . when he refused to remove the plug, we took the appropriate deduct for a "modified" tonowanda block. he did not protest too vehemently . there is definitely enough casting meet in the plug's normal location to drill and tap the area for a pipe plug. at least I'm told that's the case. the cheater block in the white 57 FI that was involved in the dipstick races of the early 90's was one such modified tonowanda block. mike

Now when judging I will have to allow for Maryland machined and assembled engines.

[Wayne G.]

Re: '65 Tonawanda block

This may finalize the mystery. The front of the block does NOT have the threaded pipe plug. Also with close examination it looks like there are grinder marks across the O on the engine pad and looks like it was originally stamped a C and then stamped to close the C to an O, for who knows why. It appears as Cecil was right though. Just another 327 block to kick around, but the good news is I have some nice '64 parts to barter with!

Wayne

[Mike D.]

Re: '65 Tonawanda block

Those 64 parts would go nice on a 65 pilot car with a May build..... no word on VIN# 9.

[Wayne G.]

Re: '65 Tonawanda block

I contacted Martin a couple of times, but no call back concerning'65 #009.