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dvx304racer
03-08-2009, 08:00 AM
sry to be a pain but i was just wondering i have a 07 dvx400 with a slip on exhaust air filter jet kit and stage 1 hoy cams with kibblewhit stock valves if i get a big bore kit do i have to switch to stage 2 cams and titanium valves and valve springs???
cataway
03-08-2009, 11:09 AM
no
dvx304racer
03-08-2009, 11:39 AM
ok thanks and will a big bore kit take away my top speed and give me all torque
cataway
03-08-2009, 12:18 PM
a BBK with out the mods that complement it is a failure waiting to
happen.
do you see my mods in my sig ? thats 40+hp on a stock bore
you will spend way more than i did and not even get 35 hp till you get the right pipe ,the right intake, clean up the porting and get a cdi,
dvx304racer
03-08-2009, 01:51 PM
so what r u trying to say a shouldn't buy a BBK or what
cataway
03-08-2009, 02:25 PM
thats right ,not yet
get a full pipe and a 400ex intake boot first ,you will be surprised
what that will do for you
kawiracerj
03-08-2009, 04:44 PM
whats the plus for ading the 400ex intake boot?
cataway
03-08-2009, 05:16 PM
2-3 hp
kawiracerj
03-09-2009, 10:50 AM
lol sorry i wasnt clear.why do you use the 400ex boot whats the diff? why it and not z400 what does it do different?
cataway
03-09-2009, 01:23 PM
http://i44.photobucket.com/albums/f9/cataway/9-21-2007LS027.jpg
as you can see in the pic the ex boot is much straighter ,this makes it easer for air to get through it.
more air more gas = hp
its not the only other boot used,but it can be hooked up to the air box with some modifications.
i use one from a trx450r,no air box

soon i hope to try one from a ds650

there are of course other intakes but these are known and easy to get and not very expensive
kawiracerj
03-10-2009, 08:46 AM
i dont have the option of running"no air box" but ill give the 400ex boot a try,cause i still have one in junk pile.thanks for explaining it to me!!!!
PLCracing
03-20-2009, 12:57 PM
Hi, just browsing the posts. I'm building my '05 z-400 now. I've got a 434cc kit, 400ex boot, Alba full pipe, jet kit, hot cams on the way, and about to port the head. Just wondering how much of an improvement is replacing the CDI? Hadn't thought of that yet.
cataway
03-21-2009, 05:41 PM
getting a dynatek cdi is a great boost ,it gives a better tq curve and an extra 1000 rpm's,its really the only one you even want to consider
i hace some dyno graphs to show what it did for me ..........some were