Camshaft help
- Thread starter merlin
- Start date
L0rdMike said:265/270BHP
Was good to see you again a few days back, you must have been thinking who the when I rolled up next to you.
Just noticed this - yeah lol, it took me a few seconds to register who I was looking at, then I went to turn the stereo down so I could chat to you two but I dropped my cake.
Simon said:
Yeah System-R just came back to me to say they dont skim the head, and they've never ever had a rebuild back, so that's one problem out the way.
Stock retainers are ok, but how much are titanium ones? Engine will spin at 9200rpm with these cams and springs, peak power 8100rpm.
Last edited:
mrk1@1 said:
Umm, no, I fitted them myself to avoid the costs. Otherwise Regal would have had to remove the head etc. They set them up tho once the other mods had been completed.
kaiowas said:
A performance cam effectively lowers the compression ratio because it increases valve overlap. Therefore, if the engine tended to pink at normal compression on low quality fuel, it will be less likely to pink with the performance cam, raising it further is a bonus
Oracle said:
The increase overlap will cause lower VE at lower speeds also it could be argued that 'dynamic' compression has reduced.
Pinking is due to ignition timing and if a performance cam is eliminating pinking it will be due to a slower burn. Hardly a 'performance' cam.
Titanium retainers are good for higher revs obviously. They don't last it that long though and need replacing after 15-20k.
Number one cause of s2000 failures is a cracked retainer due to an over rev letting go and dropping the valve into the engine
So make sure you check out the retainers can cope, might be worth going for some s2000 ones? Later AP2 ones are stronger too apparently. Depends on a lot of things, weight of valves and spring strength. Anyway you probably know a lot more about it than me.
Look forward to the results!
Cheers.
Think I'll just replace the current ones with same spec but brand new. Although there's 9200rpm available, I'll likely not go much beyond 8800/8850rpm anyway, it's should be pretty quick without the need to rev the nuts off it, peak power coming at much the same rpm as the standard cams (albeit they can hold peak power flat for 1100rpm), plus I dont really want to overstep oil pump efficiency.
On holiday next month, will start to get a battle plan together after that.
Think I'll just replace the current ones with same spec but brand new. Although there's 9200rpm available, I'll likely not go much beyond 8800/8850rpm anyway, it's should be pretty quick without the need to rev the nuts off it, peak power coming at much the same rpm as the standard cams (albeit they can hold peak power flat for 1100rpm), plus I dont really want to overstep oil pump efficiency.
On holiday next month, will start to get a battle plan together after that.
