[FRRACER]

I am in the process of preparing my head where by if in the future I want to fit higher lift cams of around 10.25mm I can simply drop them in with out taking the head off.

How much needs to be machined either side of the lifter? Any ideas? I do not have a high lift cam so cannot use that to see how much needs to be taken off. Someone must have some details?

 

[nailsgtr600]

I'd be doing a piston to valve clearance while your at it..
The last thing you want is to bend some valves...

 

[FRRACER]

I already have recessed pistons. Just need to know how much to shave off the head so when I do buy them the higher lift cams do not hit the sides of the head.

 

[Piggaz]

It's not much. 4 mm would be heaps.

You're game doing it in the car. All that metal flying around.

I have a few photo's from my build. This photo has 260 @ 10.85 mm using the stock base circle (custom grind cam).

 

[Piggaz]

 

[FRRACER]

Thanks The head is off the car hence why now is the best time to do the mod.

BTW where did you get your cams made? Or old ones reground? They do custom profiles right?

 

[Clark Motorsport]

It depends on which cams you go for, profiles base circle etc.....

Which cams are you going for??

 

[FRRACER]

Right now Poncam Type A, but later something with more lift yet to be decided.

 

[Clark Motorsport]

Tomei all the way for me .... even though I don't work for them now.

HKS you will get away with Tomei require cutting back they are in my opinion the best

 

[Piggaz]

Thanks The head is off the car hence why now is the best time to do the mod.

BTW where did you get your cams made? Or old ones reground? They do custom profiles right?

We made our own. We spun up some Japanese cams (Tomei 270 @ 10.25 mm and a JUN 264 @ 10.5mm) and found their ramp rates to be very very mild. We weren't happy with that so we found a lobe (its actually an Alfa Romeo, naturally aspirated lobe) and put them on some blank shafts. 260 @ 10.85 mm, uses stock buckets and is requires half as much duration to get to your 50 thou of lift. Hard on the valvetrain but who cares.
We are actually looking at making a 250-252 at more than 11 mm of lift.