Reducing Compression

[Jason Plato]

Yes - the head has been skimmed too far .

 

have a word with "Tom 7" here on blatchat , for a replacement VHPD head

 

You wont need to do any work on the accralites if you get a new head that has not had a skim or you can take upto 8 thou off it easily with the accralites and all will be OK .

 

I speak from personal experience .

 

dave

 

 

 

Edited by - Dave Jackson on 27 Mar 2004 20:38:32

[mav]

Dave,

 

What compression ratio did that leave you with???

 

We have done a lot of calculations based on a new VHPD head having 29.5cc per chamber.

 

If this is the case then to get a reasonable cr ( i.e 11.5:1) then some material will need to be removed from the pistons too??????

[Jason Plato]

Lets just say that I have run accralites for the past 3 years . My previous head ( the K16 one ) had been skimmed twice and all was OK .

I'm now on a brand new VHPD head that hasnt been skimmed ( owing to future developments) and the compression is less than the K16 and all is well .

 

The car was mapped at Emerald a short time ago and the compression was fine .

 

This is of course assuming that the design of the accralites hasnt changed in 3 years . I would check with accralite what is the actual increase in size .

 

From looking at your photos it appears that the "D" on the casting has been skimmed away - I recall this represents 27 thou ++ (please correct me if I'm wrong) .

 

 

 

When I bought my accralites it was as a part of a bulk buy , there must have been at least 12 of us all using these at the time and many are still on the same ones with different heads and with no problems .

 

Dave

 

 

 

Edited by - Dave Jackson on 28 Mar 2004 09:15:12