hey wats the difference with 4-2-1 and 4-1 extractors?

 

cheers

generally tri-y extractors are used on v8s, it's said that you get more torque out of them but they restrict top end. they're really just a compromise and a waste of time

 

get 4-1s

I fully disagree there Jamie,i recommend 4 into 2 into 1s.

david vizard also reckons 4-2-1s are shit, i'm sticking with him :)

Good for you,bet he`s built lots of K series motors.

4-2-1's on EVO1 work goodly. Pro's and con's for both.

no, but he's built lots of pushrod engines with wedge shaped combustion chambers, and lots of non crossflow engines, and he's been building motors longer than i've been alive, so yeah :)

I've got 4-2-1, I'm happy so far.

i had 4-2-1 on my mini and it made good use of the 1100cc engine had a nice muffler too, dam i miss my old clubman sob

Found some old pics of the mini just had to scan them hope they come out right

I know its off topic but it was a sweet little car my first love untill the rolla arrived hehe :) I still have a soft spot for the mini tho

At first thought I assumed 4-2-1 would be better because its a "smooth transition" but I have read a few sites, apparently 4into1 are better. Would be interested to hear someone explain the pros and cons.

hey guess what!! no one has explained to me what each one means :) but what costs better, has better performance etc etc.. thanks

4 into 2 into ones give better midrange with the sacrifice of some top end power 4 into 1s give less midrange and more peak seeing as how most people on here are into build road motors 4 into 2 into 1s are the way to go.

The more radical an engine is in regaurds to camshaft timing the more critical and fussy they become in the exhaust,bigger diameter pipes move the torque peak up the rpm range smaller pipe diameters move it down changes in length of the pipes tends to "rock" the torque curve around the point of peak torque.If you have a mild cam and its for the road any decent set of extractors will be fine.

i beg to differ, my cammed 4k made bucketloads of torque down low, i couldn't have wanted more, i could however have used more top end

 

on a K motor, i think pipe diameter is more important than design, bigger primaries would have been awesome. ideally, you should get extractors custom made for the powerband of the engine