What are the largest cams I can run with my set up?

[rallypvc]

I have a cg13de with cg10 pistons and 40thou skimmed off the head what are the biggest cams I can run without getting valve to piston contact?

 

[frank]

my 260/10mm inlet and 272/9mm exh cams have loads of clearance, it depends how much overlap you set them at really

 

[rallypvc]

Was going to set them to standard wanted some with more lift to make the most of my bike itb set up

 

[frank]

Was going to set them to standard wanted some with more lift to make the most of my bike itb set up

the lift wont affect piston/valve clearance tho eh, just the duration/overlap
and stock springs get coilbound on 10mm+

 

[rallypvc]

Been looking at some piper 258s so think they'll be ok

 

[frank]

Been looking at some piper 258s so think they'll be ok

my exhaust cam is a piper 272, they are very tame tbh fwn and shimming them can be a pita

 

[rallypvc]

Hi Frank I know from reading several posts your a bit of an expert on cams so what cams, duration and overlap would you recommend to work best with what I'm running?

 

[frank]

Hi Frank I know from reading several posts your a bit of an expert on cams so what cams, duration and overlap would you recommend to work best with what I'm running?

matt (mph) does direct fit cams eh, (500 ish) or else there,s the piper 272/9mm (200 ish) which are pretty tame but are ok to high rpm (tho shimming is an issue fwn )
or my prefered choice of autosprint 260/10mm (160 ish) which have quite aggressive ramps and need underbucket shims

 

[rallypvc]

The engine is going to be used in a rally car so need good mid range hp and torque what sort of size shims do you use on the autosprint ones? What material they made of?
Can standard springs be used with them?

 

[frank]

i use a 2nd stock shim with the autosprint one, and a 2nd ground down shim with the piper, and i,ve only ever used stock springs

 

[rallypvc]

i use a 2nd stock shim with the autosprint one, and a 2nd ground down shim with the piper, and i,ve only ever used stock springs

Excellent think I'll be giving autosprint ring then!

Would I see any benefit from having the crank lightened and balanced?

 

[frank]

Excellent think I'll be giving autosprint ring then!

Would I see any benefit from having the crank lightened and balanced?

geoff at autosprint can balance the crank if you want but i would,nt bother personally, and mine runs with both shims under the buckets (the 260/10mm profile has been known to spit shims )

 

[rallypvc]

Just had a quick look on the autosprint website didn't see any micra cams listed I take it if I give them a call tomorrow they know what im after?
Also are they an off the shelf item or will I need to send them my cams to be reground?

 

[frank]

Just had a quick look on the autosprint website didn't see any micra cams listed I take it if I give them a call tomorrow they know what im after?
Also are they an off the shelf item or will I need to send them my cams to be reground?

aye, he,ll know what you,re after :grinning: and you,ll have to send yours

 

[swsupermot]

Anyone got any cams going begin