Ram Air IV versus 455 HO

[Charley Lillard]

Can I just run the stock rockers ?

[Steve_Hoog]

Yes you can run stock lifters, Pontiacs are much better at top oiling than a Big Block.

[supergonzo]

You can run stock rockers 1.50 ratio if you want but why??
If you are getting an expensive HR cam why would you put stock rockers on it. You could get roller tip 1.65 ratio rockers, but if you gonna do it, do it right.Get Roller Rockers. They will fit under the stock valve covers, if you use 2 valve cover gaskets. Look Stock....Go Fast

Steved...I think you meant stock rockers, not lifters with the HR cam

[Charley Lillard]

I don't want to double the valve cover gaskets, now what ?

[supergonzo]

So use roller tip rockers, they look like stock rockers with roller tips. Comp Cams has those as well.

[DaJudge]

Use the Ram Air IV valve cover gaskets they are thicker because the IV's use 1:6 rockers stock. Ames or Performance Years have them in their catalogues.

[supergonzo]

RAIV valve cover gaskets are the same as any other valve cover gaskets. The rockers are 1.65 ratio stock, but they were stamped steel and not any bigger than 1.50 ratio rockers. Only Aftermarket Roller Rockers need 2 valve cover gaskets to fit.

To add one more thing to Mike Noun's point about the 455SD motor in 1973-1974. Most performance cars with lowered compression and added emissions at this time were solid mid-high 15 second cars. The 455SD was burdened with the same problem, but was running at least 2 seconds faster than the competition in a 4000lb car!! That is really almost unbelieveble. Too bad it wasn't made in 1970 with high compression & less emission garbage, with an open hood scoop.....it probably would have been considered the ultimate muscle car mass produced engine.

[GTO_DON]

bill, your right that the 1.65's are the same size, BUT, because of the pitch of the rocker they will hit the valve covers! RAM AIR IV'S ABSOLUTLY TAKE THE THICKER GASKET! HAS ITS OWN PART NUMBER. look it up,its in the service manual..

[supergonzo]

maybe this will clear it up. I have 2 RAIV's always used the RAIV gaskets and never noticed they were any different.

[DaJudge]

Supergonzo, I guess I will throw out the two NOS sets I have since you say they don't exist, they are infact almost a 1/4 inch thick and carry a different part number. A lot of Poncho people don't know that the IV's valve cover gaskets are thicker, go figure. They also used longer valve cover bolts. The valve cover gasket part number is 9797580 and the bolt part number is 9784378.