performance cam ?????

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333i
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Mon May 26, 2014 1:46 pm

can anyone reccomend a cam for my m20b25 cheers
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gooner1
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Mon May 26, 2014 2:22 pm

What is your objective?
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333i
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Mon May 26, 2014 5:38 pm

dunnoooooo lol
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reggid
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Tue May 27, 2014 8:53 am

then save your dollars
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333i
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Tue May 27, 2014 9:38 am

more powerrrrrr
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Shaheenk
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Tue May 27, 2014 9:43 am

Shrick 288 Deg
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reggid
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Tue May 27, 2014 10:56 am

schrick 272 is a pretty safe bet and will not usually cause issue with the valves smashing pistons and will still be civilised.

anything more might cause problems and will be a compromise without supporting mods.

swapping a camshaft alone will rob from peter to pay for paul
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swainerjim
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Wed May 28, 2014 9:02 am

what sort of supporting mods?
chip,manifold, full system and induction kit?
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333i
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Wed May 28, 2014 1:12 pm

induction kit and scorpion exhaust atm will be ordering a chip soon
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reggid
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Thu May 29, 2014 3:47 am

swainerjim wrote:what sort of supporting mods?
chip,manifold, full system and induction kit?
after market ECU to be able to properly tune (or similar) and higher CR and adjsutable cam gear as a minimum IMO if you want something like a 288 schrick. chances are something with that much overlap will be smashing into pistons so this needs to be addressed to

if you dont you will lose lots of bottom end torque and not be fun on the street for 90% of the time

recommended also cylinder head work, 6 branch, ITB if you want the most out of it
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swainerjim
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Thu May 29, 2014 11:08 am

what if your only thinking of 272?
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reggid
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Thu May 29, 2014 10:33 pm

don't need head work and all that stuff, it just works better if you do. 272 is probably a little big for the low comp b25 to be ideal but will work.

make sure valve springs are in good order using a spring tester.

i'd always get new rockers with a new cam so they bed in together but im sure others dont feel the same way.

check clearance valves to pistons and a adjustable cam gear wouldn't hurt though many have saved pennies and gone without

a plug and play chip will work fine if you find someone reputable .

pulling the head for a nice refresh does wonders as well.
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Sat Jul 05, 2014 4:16 pm

reggid wrote: recommended also cylinder head work, 6 branch, ITB if you want the most out of it
Surely an ITB setup is a little extreme just to make a bigger cam work Digger. Surely this is the final step to total M20 perfection, but for most applications a BBTB plus and suitably honed intake plenum would suffice.

I do agree with your other comments however. I also agree that e 272º cam is an excellent choice for a street car. I will make the engine lumpier and more aggressive, but will not kill off that important low to mid range like a bigger cam will. You also do not need too many other modifications to make it work. Look to invest in an adjustable cam gear and a simple tuneable ECU (I use the Miller WAR chip personally) or at the least a piggy back chip to help get the best out of the bigger cam.
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reggid
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Sun Jul 06, 2014 7:28 am

MillRat wrote:
reggid wrote: recommended also cylinder head work, 6 branch, ITB if you want the most out of it
Surely an ITB setup is a little extreme just to make a bigger cam work Digger. Surely this is the final step to total M20 perfection, but for most applications a BBTB plus and suitably honed intake plenum would suffice.

I do agree with your other comments however. I also agree that e 272º cam is an excellent choice for a street car. I will make the engine lumpier and more aggressive, but will not kill off that important low to mid range like a bigger cam will. You also do not need too many other modifications to make it work. Look to invest in an adjustable cam gear and a simple tuneable ECU (I use the Miller WAR chip personally) or at the least a piggy back chip to help get the best out of the bigger cam.
it is recommended to be get the best from a 288 cam and above but not mandatory!

i do stand by it, the results will be much much better in every single facet. i.e idle, part throttle, WOT power and torque across the board, better tunability, throttle response....

your engine is crying out for some, id say you be 20rwkw more with yours...
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MillRat
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Sun Jul 06, 2014 7:28 pm

reggid wrote:
it is recommended to be get the best from a 288 cam and above but not mandatory!

i do stand by it, the results will be much much better in every single facet. i.e idle, part throttle, WOT power and torque across the board, better tunability, throttle response....

your engine is crying out for some, id say you be 20rwkw more with yours...
I agree that my engine needs a setup like yours. This will be on the cards when I move back to Australia at the end of next year.
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reggid
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Mon Jul 07, 2014 7:13 am

MillRat wrote:
reggid wrote:
it is recommended to be get the best from a 288 cam and above but not mandatory!

i do stand by it, the results will be much much better in every single facet. i.e idle, part throttle, WOT power and torque across the board, better tunability, throttle response....

your engine is crying out for some, id say you be 20rwkw more with yours...
I agree that my engine needs a setup like yours. This will be on the cards when I move back to Australia at the end of next year.
that distance does present a rather large obstacle
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e21jps
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Mon Jul 07, 2014 10:55 pm

compression is the biggest factor to consider with cam choice, otherwise you will just end up robbing Paul without paying Peter!

272 is a good all round cam for mild compression, 288 will only work well with more comp and as pointed out PV clearance usually needs to be addressed.

Ibs are good on ANY motor if done right, we have proved they can make a healthy power and torque increase right across the rpm range even with no supporting engine mods..... with a 272 and/or higher comp etc the gains will just get a bit better!
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Mon Jul 14, 2014 6:43 pm

reggid wrote:schrick 272 is a pretty safe bet and will not usually cause issue with the valves smashing pistons and will still be civilised.

anything more might cause problems and will be a compromise without supporting mods.

swapping a camshaft alone will rob from peter to pay for paul
as Said Above .

The 288 schrick is a bit racing one , Also makes the car bouncy on low RPMs .

If you have a daily driven car and you need amazing power ,
get the 272 schrick , which safe and gives you a nice gain .

Also if you have an L cam on your 325 , and you need a bet faster inlet and outlet , install a K cam , pretty much better than the L one , which goes for economy .
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reggid
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Tue Jul 15, 2014 3:52 am

i measured an L cam from a 320i and lobes were identical to the K lobes from a B25, albeit the timing a little different but an adjustable cam gear would do the same job. there is nothing worthwhile to be found from swapping the "i" cams get an performance one, even a regrind if budget is limited
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