Valve Cover Retainers and Spec Hi Perf

[Keith M.]

Two unrelated questions.

Just curious why some engines they used valve cover retainers and others not?

Also, I see some language about a Spec. Hi. Perf engine in 1969. Just want to confirm that is NOT the L46? Appears that refers to the LT1??

Thanks,
Keith

[Duke W.]

Re: Valve Cover Retainers and Spec Hi Perf

I don't understand what you mean by "valve cover retainers, although stamped steel valve covers

The '69 L-46 was considered a SHP engine as is the LT-1 which was not available until the 1970 model year.

For '70 the L-46 might be referred to as SHP with hydraulic lifters and LT-1 as SHP with mechanical lifters. This would be consistent with the terminology in the parts catalogs used to describe the '65 L-79 and L-76, respectively.

Duke

[Keith M.]

Re: Valve Cover Retainers and Spec Hi Perf

Duke,
Check out this link which covers both my questions. This is an example of valve cover retainers. Also, in various documentation sources, parts catalogs (as in this link) it sometimes stipulates something like "w/Spec Hi Perf". I just was not clear that the L46 was such.

https://www.paragoncorvette.com/product/358858/valve-cover-retainer-kit

[Duke W.]

Re: Valve Cover Retainers and Spec Hi Perf

Those were used on some engines with stamped steel valve covers. The page says 66-81 base engines, but that may not be the complete list. Others needs to chime in. They weren't used on SHP small blocks with aluminum valve covers because the bolt bosses and rails are much stiffer than the stamped steel valve covers.

I recall buying valve cover gasket sets that included little gaskets that matched the plan form or those "retainers" that I just threw away since they weren't required on my 327/340 that have "Corvette" aluminium valve covers.

I recall F5000 engine builders used plain steel valve covers and what looked like small leaf springs under the bolts that spread out the load over two to three inches either side of the bolt, and it's my understanding that they were production on Corvair engines.

Duke

[Larry E.]

Re: Valve Cover Retainers and Spec Hi Perf

Here is a picture of what Duke is talking about. Picture is a Traco Trans-Am Camaro engine. BTW>Duke I do indeed remember going to Road America to watch the F 5000 with drivers like Andretti/Redman/Unser. Those lightweight cars would just roar
down the straights at R/A. Valve Covers where Chevy Orange. Larry

[Keith M.]

Re: Valve Cover Retainers and Spec Hi Perf

Ahhh....so their purpose was to spread the pressure across the valve cover lip creating a better, more even pressured seal.

[Leif A.]

Re: Valve Cover Retainers and Spec Hi Perf

Ahhh....so their purpose was to spread the pressure across the valve cover lip creating a better, more even pressured seal.

And, to help deforming the thin metal edge/hole of the valve cover.

[Chris T.]

Re: Valve Cover Retainers and Spec Hi Perf

Yes, as stated, originally used on Corvair valve covers. They were adopted by enthusiasts to help with valve cover leaks on small block V8's. P/N was 3850874.IMG_1707.jpg

[Steven B.]

Re: Valve Cover Retainers and Spec Hi Perf

I remember those little gaskets too Duke! A long time ago. I threw mine away too.😊

[Duke W.]

Re: Valve Cover Retainers and Spec Hi Perf

Here is a picture of what Duke is talking about. Picture is a Traco Trans-Am Camaro engine. BTW>Duke I do indeed remember going to Road America to watch the F 5000 with drivers like Andretti/Redman/Unser. Those lightweight cars would just roar
down the straights at R/A. Valve Covers where Chevy Orange. Larry

I went to the Can-Am and Trans-Am races at RA when I was a grad student at the U. or Wisconsin Engine Research Center in '69 and '70. By the time I got to CA in the mid seventies the Can-Am was pretty much gone from the cubic dollars invested by Porsche in the 917s, but F5000 was a great and more affordable series.

I recall at a F5000 race at Riverside, sometime in the mid-seventies, Mario when out solo to do a few hot laps and try to set a course record, which he did probably eclipsing a record set by Donahue in a 917 with what was basically a souped up version of the engine in my SWC.

Many may not remember that the first Long Beach GP was F5000 not F1, and the hot setup was a Lola T-332 with a 5L Chevy SB, stock block and (full race ported) heads, with a IR injection system and racing exhaust system. They reputedly made about 500 bhp and revved to 8000/8200. F1 was the following year, and I recall they were just marginally faster than F5000.

I recall Brian Redman won that initial LBGP driving Jim Hall's Boraxo sponsored Lola T-332.

F5000 was a great series. It evolved into a "revised" Can-Am using past F5000 cars with envelop bodies, and I recalled it faded away due to the late seventies '"oil crisis".

Look a those exhaust ports on the Traco TA engine. Wow! They were probably done by Valley Head Service, and I think they are still around. This must be a '70 version since it's wearing a single 4-bbl carb rather than the 2 x 4 cross ram system.

Duke

[Larry E.]

Re: Valve Cover Retainers and Spec Hi Perf

Pulled up a past thread from our "Master" Joe Lucia>>

[Richard F.]

Re: Valve Cover Retainers and Spec Hi Perf

Attached is the Fel Pro version of the O.E.M. reinforcement washer. States washers not required for 1968 up.
RichDEBF58B7-1747-4579-8078-C64D78E03A42.jpg6316AB61-E7A0-4874-8155-127E941C0FE6.jpg

[Joe L.]

Re: Valve Cover Retainers and Spec Hi Perf

Attached is the Fel Pro version of the O.E.M. reinforcement washer. States washers not required for 1968 up.
Rich[ATTACH=CONFIG]115936[/ATTACH][ATTACH=CONFIG]115938[/ATTACH]

Rich-------


No GM valve cover reinforcement was ever of this exact configuration but these should work fine.

[Joe L.]

Re: Valve Cover Retainers and Spec Hi Perf

I don't understand what you mean by "valve cover retainers, although stamped steel valve covers

The '69 L-46 was considered a SHP engine as is the LT-1 which was not available until the 1970 model year.

For '70 the L-46 might be referred to as SHP with hydraulic lifters and LT-1 as SHP with mechanical lifters. This would be consistent with the terminology in the parts catalogs used to describe the '65 L-79 and L-76, respectively.

Duke

Duke------

As you say, for 1969 the L-46 was "SHP" since there was no LT-1 available. For 1970 the L-46 became "HP" since there was an LT-1 available which was then "SHP"

The last time before 1970 I can think of that "HP" was used for a small block was 1963-65 (when the base engine was 250 HP) and the L-75 300 HP was carried as "HP".

"HP" was not used as an engine designation again for Corvettes after 1970.