292deg Cam With 13mm Lift (piper P16727)

[Guest sgratton]

G'day all

 

Today I have been attempting to fit my new cam that is a piper P16727 cam with 13mm lift and 292 duration. When I started fitting it I wondered whether it would go in the head because it is more than noticable that it has loads more lift. As I suspected the lobs hit the head cast. The result is that I need to take the head off, remove the valves and machine the cast to provide clearance.

 

Then I thought if the head is coming off then what else can I do. Does anyone have any experience of this cam and are there any thoughts about whether to increase the valve size or not? Also do I need stronger valve springs?

 

A bit of back ground.

The car is a rally car, so I don't care about how good it runs and idles as long as the set up works above about 3500rpm. Currently the car has a standard engine which was fully rebuilt about 1000 miles ago, but the plan is to fit this cam and Yamaha R1 carbs.

 

I have read many of the posts about tuning and cams, but I was just wondering if anyone had direct experience of this cam.

 

Thanks everyone.

 

Si.

[PumaRacing 2]

Haven't come across that particular cam yet but if has that much lift then the standard springs are going to be coilbound or at least very close to it so you'll have to use different ones anyway. The tuning article on my website should answer your questions.

[Guest sgratton]

Thanks Dave,

 

I have seen your web site, it is most imformative. Thanks for you input. I will be in touch with regards to springs.

 

Si

[veloce200 3]

Thanks Dave,

 

I have seen your web site, it is most imformative. Thanks for you input. I will be in touch with regards to springs.

 

Si

 

IIRC this is the cam they market for Race where std plenum needs to be maintained - probably a bit less duration and higher LCA than the full on race one. Should be just what you need !