1.9:1 ratio rockers to suit Buick (non ecotec) V6's

[LX_HATCH]

Its not hitting on the top but hitting on the injector side of the rocker cover. I die grinded some off yesterday but didn't get it all fitted back up.

As for gaskets I called a local autobarn and they are going to get back to me today.

Karlos what car did you have the issues on?
What rockers were causing the issue?

 

[karlos]

My old VS,FIT rockers and these covers.Was not heard of before apparently.

Killkennys used to hit on my 308 aswell with yellaterras,same fix.Killkenny Castings have bad batches from time to time with everything.

 

[LX_HATCH]

Yeah they are still hitting, and yes there is a slight mark on the top of the rocker cover, so I will be getting a new set of gaskets and doubling them up as well as giving the injector side a good grind.

DO any of the big auto stores stock them?
Autobarn were meant to ring me back today and didn't bloody call!

What about spacers?

 

[LX_HATCH]

Got some more info.

Autobarn can get the gaskets (~3mm) for $25 each. I called a local gasket place and they can supply me a 1200x700 x 6.4mm sheet of cork gasket, so I will be purchasing a sheet and cutting my own gaskets.

I will have heaps left over so if anyone else needs 6.4mm cork gasket for Killkenny rocker covers I will be able to make them up.

Autobarn can also supply rocker cover spacers for $90 a pair.

Hopefully I will get the covers fitted tonight with the thicker gasket.

Ryan

 

[VS_Pete]

Sounds like you are on a winner there Ryan.
Good Luck.

 

[LX_HATCH]

Thought I was lol.

Still hitting but not as bad, probably on the injector side still. Im going to pick up a set of the standard covers from the wreckers and compare them against the killkenny. Then fit them and see how it goes, the thing is if the rockers were hitting the standard covers I doubt any extra noise would be produced as they are plastic.

 

[MACE]

Id be very surprised if they hit the standard rocker covers. We've tested these on both styles of factory rocker covers VN S1 (die cast rocker covers) and VN S2 (plastic) rocker covers with no problems. However I'll have to have a check again under my rocker covers again though. That would probably have been about the 20th time they've come off now at least

 

[LX_HATCH]

Yeah im up to 10 times !!

Hopefully have some news tonight.

 

[Immortality]

Some Technical stuff

For Those that haven't seen these yet, here are some pics of a MACE 1.9:1 roller rocker Vs the standard 1.6:1 buick rocker.

You'll notice that the roller rocker is smaller then the stock rocker. the roller rocker is also lighter. what this means is that there is less mass in the valve train. Less mass in the valve train means a faster accelerating engine (i.e. it revs faster). Less mass in the valve train also means that less valve spring pressure is required to control that mass which means less chance of valve float/bounce

so even if you wanted to maintain a stock rocker ratio (these rockers are fitted as standard equipment to the gen III V8's in 1.7:1 ratio) due to using a high lift/duration cam shaft using this style of rocker in place of the stock buick rocker will give some advantages

 

[LX_HATCH]

Ok changed to original rocker covers and the noise still comes back when the engine is warm.

Has anyone got any ideas?

What could cause the rattly noise?

How much clearance is there between the valve and piston normally? Is there anyway I can check the clearance when the valve is fully open? What if I take a spark plug out?

I have had the engine rebuilt with a stock cam, can anything else affect this clearance?
Having the block decked?
Head work?
Ground crankshaft?

Do the crow double valve springs need to go in any particular way? They seem symmetrical.

If not I will have to put the original rockers on but keep the upgraded valve springs on, before my drag day on Saturday as i'm worried I will cause major engine damage!

Thanks again Ryan