[BigBlock69]

I am in the process of doing a cam swap on my 454. I am going from a comp 268 with 485 lift to a xtreme 274/286 with 552 and 555 lift. Rockers are being upgraded from stock to comp magnum roller tips with 1.72 ratio. Heads are GM 781 ovals. Valve Springs are going to be comp 924-16. What valve seal do you guys recommend and will I have clearance between the seal and the valve guide? I am doing this swap with the heads on the vehicle, unless they have to come off for guide machining, which I would like to avoid. Any help would be greatly appreciated.

[Bumpstick]

You should have plenty of clearance (you do mean between the top of the guide and the retainer...?) As for a seal my machinest uses the ones that come in the Felpro sets...? Also you do have the rotator eliminators already I assume...? (under the exhaust springs) Also that is alot of lift as I understand for a roller tip rocker...? I too was going to use that same rocker but went with SS full roller rockers... That cam has some nice spec`s but what compression are you running with the open chamber heads...?

[BigBlock69]

THe block has been decked .010, the heads have been milled .030, the pistons are flat top which makes my compression ????????? probably low. From what I read about this cam, it fills the cylinders very quickly and compensates for a lower compression ratio. Do you buy it or is the compression going to be too low to use this cam? I haven't swapped the springs yet and the valve rotators are still under the exhaust valve, Who makes this rotator eliminator and why do I need to use it?

[Bumpstick]

If I`m not mistaken with the high lift of the cam and the type of springs your using the factory rotators will cause problems...? Might ask one of our machinest guys on here (Bob...?@aol.com) Also the cheapest place I have found so far is on fleabay for the rotator eliminators... The ones they sell are good for anything other than roller springs which require chrome moly type because of the excessive spring pressures and movements...

Your compression should be around 8.5-9.0 to 1 which seems a little low but the big guts of 454 cui and the oval port heads should make good low end anyhow...?

[BigBlock69]

Thanks for the advice, what I should do is tear it down and up the compression like I should have in the first place, but now I'm married with children and the budget is limited. The bottom end has to stay this way until I win the lottery or something breaks. I wonder which will happen first? Looks like I have some more homework to do on the rotator eliminator subject.

[Bumpstick]

Nah... Think you would be ok even with the compression issue...? What type of car is this and what gear...? That will make a diff as well... Also the sound will be very nice... You might also consider contacting Compcams and tell them what you have and possibly adjust the cam (advance or retard) to help with the setup...?

I know what you mean "married with children" so we do what we can when we can... I planned and accumlated for my BBC project for almost a year before it made it in my truck...

[BigBlock69]

The car is a 69 malibu that I have owned for 16 years. It was a 307 powerglide with a 3.08 peg-leg. Seafoam green inside and out. I literally bought it from an old lady who wanted Air conditioning and a radio. It is now a .030 454, Edelbrock performer, edel 750, accel hei, 1 7/8 headers into 3 inch pipes, a hurst pro matic 2 shifted reverse pattern manual valve-body 400 with a 3000 stall and a 4.11 gear. Just had it painted red and have redone the interior in black. Its slowly getting to where I want it. I throw money at it when I can. It ran plenty strong with the 268 but the quest for more power always prevails........