zride91

Hello,

I am new to the forum, mostly because I do not have a Vette , but I am hoping to pick some of your brains...

I'm building a 383 TPI for my 91 Z28. I dig the center bolt magnesium valve covers that came on the 1986-1991 L98 engines in the C4, they go with the nice aluminum TPI plenum very well. I saw a set in my old 2003 GM performance catalog, but as much of you probably know by now GM has discontinued the left, then recently, the right sides. These pieces need to be a part of my car, I have looked everywhere. My local GM dealer can still get the right side valve cover.

Has anyone taken off their valve covers and noticed if the left and right sides are the same with the exception of the Vette logo and oil filler between the two sides?? I am contemplating on getting two right side valve covers, plugging the oil filler hole some how, and getting the new aftermarket Vette logo. Does any one know of anything that migh not make this possible? Better yet, does anyone know where to get the left side (with the logo) new??

I really appreciate any help.

If anyone can even get me photos of the inside of the cover with the logo, just to see what GM did with it, it would be much abliged.

Aggravated4life

This may not help but is some info...
I had a Late or L86 with centerbolt valve covers and the oil cap opening was different than the later models.

My covers were in bad shape so I bought new ones,some years back and the oil hole was different than what my 86 had.My 86 had the same hole as an 85 design I believe.

The newer design valve covers I believed were for 88-91 and Late 86-97 had a different oil cap hole,but then GM only sold the newer ones and I had to purchase a newer cap to get it to work.

The original oil cap design was a simple push in and twist halfway cap...they were metal caps..kind of what you see on alot of older sbc valve covers...the later 88 and up cars had a hard rubber-like cap that pushed,then screwed a few turns into the valve cover hole.

Anyways,aside from that,maybe you can post a wanted ad in the C4 parts if you havent done so yet.Someone may have some older covers sitting around you can use or re-finish again and not have to deal with cutting a hole in a new valve cover and not even being sure if youre gonna get a good oil cap seal.

Just wanted to let you know there was a design difference between a few years of the L98.

Sam Lam

I do not have a photo of the interior of a L98 valve cover. However, I do have a photo of the exterior of a set of 1989 valve covers. Here is the photo:



From my cloudy memory, I believe the interior of the covers is the same except for the oil cap hole. Hope this is helpful to you.

Strick

Take a trip over to the C4 parts for sale section and make a request for these valve covers. Lots of guys replace them with aftermarket or upgrades.

http://forums.corvetteforum.com/forumdisplay.php?f=55

jsup

I have a set with all the hardware if you want them. Ihad them powder coated Silver, to look original.

I also have the Corvette logo that goes on them.

PM me, let me know.

Thanks

zride91

WOW!!

Gotta say I am extremely impressed with the quick feed-back!!!

Thank you!

Aggravated4life, the info was a huge help, I thought those oil caps were only on pre-86, excelent to know if the used route is taken.

Pictures are excelent Sam Lam, the picture of the left side w/o the logo does the same for me as the inside of the cover. Both covers look as if they have the baffle behind the PCV holes...

Have a nice New Year!

vette92_1

The only thing you might watch out for on these magnesium covers is the casting quality. I think i probably have the worst case scenario but here is a photo of how bad the castings can be.

Strick

I guess I got good ones:

vette92_1

I would say so, yours look great. I am assuming that most probably are good or decent, as my luck usually goes mine is on the worst end of the spectrum and are probably only 1 set in a few this bad.

zride91

Nice!

Yeah, thats why I want them, they look great! Not sure if I want them polished down though, looks like a lot of work (would have to do the plenum and runners too)...