Anyone running 545 lift cam with EQ heads and stock bottom end?

[Walker434]

When I built my 5.9 magnum engine I planned on running stock magnum heads so my camshaft is 230/234 duration at 0.50 and 507/513 lift. I have since switched to EQ heads but still running stock magnum 1.6 ratio rocker arms. I am in the market for some roller rockers and have been looking at the Harland Sharp 1.7 ratio rockers. With this ratio my lift would increase to 539/545. Obviously I would check my piston to valve clearance but just wondering if anyone is currently running these lift numbers with EQ heads and otherwise stock bottom end.

Cars current best in the 1/8 mile is 7.82 but like other gear heads I'm always looking to squeeze a little more out of it. Thanks in advance

 

[ValiantOne]

Can help on this but interested in the answer to your question. I think someone will chime in. If not, call Magnum Mopar or Hughes Engines. I think either one will know the answer.

 

[rumblefish360]

Excellent question IMO. I also wonder, what is the biggest lift cam someone has installed on the OE piston Magnum engine. And with what heads?

 

[skizzo]

I thiink thats right about the limit iirc.

 

[Walker434]

I've also been looking at these from Hughes. They are 1.65 ratio which would give me 523/530 lift. They run 2 rockers per shaft and don't require guide plates. Maybe these wouldn't be pushing the limits as hard.

Hughes Engines

 

[TrailBeast]

I had to get the special retainers and new 1110 springs to run .515 with plenty of room on the EQ heads and apparently the new retainers and springs allow up to about .580
Otherwise you have to get longer valves and springs or cut the guides down.
I say .580 because the consensus via Clearwater/Odessa they are capable of about .600 with the Hughes spring/retainers set and I like to shoot for plenty of room.

(All stock bottom end and pistons here also)

 

[rumblefish360]

WOW! So you can get a .580/.600 lift cam with the stock slugs? Hummmmmm. LOL!

 

[Walker434]

I had to get the special retainers and new 1110 springs to run .515 with plenty of room on the EQ heads and apparently the new retainers and springs allow up to about .580
Otherwise you have to get longer valves and springs or cut the guides down.
I say .580 because the consensus via Clearwater/Odessa they are capable of about .600 with the Hughes spring/retainers set and I like to shoot for plenty of room.

(All stock bottom end and pistons here also)

I'm running Hughes 1110 springs and retainers but not sure if it's the "new" ones you are talking about. Put this engine together 3 or 4 years ago.

 

[TrailBeast]

I'm running Hughes 1110 springs and retainers but not sure if it's the "new" ones you are talking about. Put this engine together 3 or 4 years ago.

IIRC, the retainers were actually stock for the 4. something motor.
The way to tell is if you can see the bottom of the locks sticking down below the retainers around the valve stem.