Tomei Cams

[muchogarcia34]

Hi guys

Just test fitted some Tomei Poncams into my R34 GTT. In the sheet that Tomei supplys it states that I need a 0.45mm clearance between the bottom of the cam, I cant think of the name of the part I'm looking at, and the buckets. Right now I have a 0.30 clearance on the Intake and a 0.33 clearance on the exhaust side. You can see the specs here

My question is, how do I increase the clearance from .30 and .33 to .45. Do I need new buckets or the old ones re-shimmed, as I've been told?

Any help would be great. Thanks

edit: forgot to add they are 260 degree 9.15mm lift type

Edited March 23, 2010 by muchogarcia34

[wolverine]

new shims.

[doo doo]

Try here

Precision Shims Australia

www.precisionshims.com.au

ph (03) 9723 0199

4 Fay Court Croydon Vic 3136

Then get nissan to get you a price on replacement shims.

[Swiper the Fox]

they will be fine at the clearance you have (Jun drop in cams have this exact specs)

[Cartman]

they will be fine at the clearance you have (Jun drop in cams have this exact specs)

agreed, the tighter the clearance the less noisy and provides minimal but fractionally more lift. i'd leave them as is. 

[muchogarcia34]

Cool, thanks for the input. But to leave them as they are there won't be any heat expansion or contraction with them causing any problems in the future will there?

[muchogarcia34]

Cool, thanks for the input. But to leave them as they are there won't be any heat expansion or contraction with them causing any problems in the future will there?

??

[snozzle]

if they are fine how they are now, why do tomei specify a clearance of 0.45mm when the standard clearance is meant to be 0.20mm IN and EX ??

im not saying your incorrect, but i would like to know the reason why tomei would want to make a head noisier if it purely doesnt matter?

i was in the same boat a few months ago but we shimmed them to 0.45mm and they have been fine ever since, very smooth engine operation, very chunky midrange, just a tad ticky on idle haha

[rob82]

if they are fine how they are now, why do tomei specify a clearance of 0.45mm when the standard clearance is meant to be 0.20mm IN and EX ??

im not saying your incorrect, but i would like to know the reason why tomei would want to make a head noisier if it purely doesnt matter?

i was in the same boat a few months ago but we shimmed them to 0.45mm and they have been fine ever since, very smooth engine operation, very chunky midrange, just a tad ticky on idle haha

Its all to do with thermal expansion - obviously higher horsepower cars will have higher EGTS meaning valve stem expansion will be greater. I agree with paul the clearances you have will be fine.