Reply With QuoteI think different length collectors are available, mostly from aesthetic purposes, but I run thru-Transom headers so I cannot speak 1st-hand.
ive seen a few boats on the water lately that look like the tips of the headers were really short. do people cut them or buy them like that? does it do anything performance wise. i would think it might be a little louder like that. i am just curious. i always thought they were tuned and best left alone. they look pretty sweet, thanks
I think different length collectors are available, mostly from aesthetic purposes, but I run thru-Transom headers so I cannot speak 1st-hand.
i run a short header i just like the look better.
some guys take an already short "drag" bassett and cut them even shorter. Chances are good they do it for looks rather than for making HP, ask any of those guys with short collectors if they went to the dyno, I bet they say no.
thanks for the info, yeah i think it looks pretty nice with a good setup
Is there any hp lost by running them short? It sure looks cool.
-Matt
They will cut the collector for the type of camshaft that they are running.
The more radical the cam the shorter the collector will be the length chages the amount of reversion that adds to the amount of back pressure in the header.
Less duration on the cam will allow more length which creates better scavenging through the collector.
Some people cut them for looks. Are you maybe looking at zoomies(sorry if that's insulting, some people don't know what they are)? A few people, at least in whitewater jet boat racing run these or similar:
http://www.jegs.com/webapp/wcs/store...tegoryId=10605
(sorry, I'm not trying to advertise for Jeg's, just knew I could find a picture there).
I think they look cool but man are they LOUD! I was like most people and thought you can never have a V8 too loud. I took my muflers out and ran them dry. It sounded cool for about 5 minutes and then I had a headache, even with my helmet on. On top of that I couldn't hear other things that I thought were important like my navigator screaming at me, valves clattering etc etc. I'm going to go back to muflers and even add a turn down to keep some of the noise away from me. This is probably in my head but short headers with no mufflers I don't think sound that good with a mild cam. I think maybe there's this idea of what open headers should sound like and with a stock ZZ4 cam and short collectors, it just didn't sound that good. Some of that probably has to do with listening to really stout race motors all the time and thinking mine should sound like that. Some of it probably also has to do with the lack of smell of race gas in the air when my motor is running, that smell seems to make everything sound better.
I'm guessing a little here but most people's headers are not very carefully matched to their set-ups, I know mine aren't. Dyno time and custom headers are the order of the day if you want to get the best match of headers to cam and get the most HP. That kind of $/time is not what most recreational boaters are going to put into their project for relatively moderate HP gains. Now the really fast guys who are looking for every last HP/MPH/ and tenth of a second, they'll spend the time carefully matching their primary diameter/length and collector diameter/length to their head/cam set up
Anyway, long winded I know but I'd give careful consideration to not cutting them or borrow some cut ones and give it a try before you get to cutting anything that is not readily replaceable. They do look good though-Aluminum Squirt
I'll be the first one to tell you that the short headers ARE LOUD!!!. My engine sits pretty far forward (not an issue in a jet) and those dang things are right in my ear. I'm either lengthening these ones or getting some new ones.
for example....
http://www.***boat.com/image_center/...10_resized.jpg
Posting Permissions