01-06-2010, 02:43 PM #1
Intake manifold sleeve, smooth or helix ?
Came across the TBM racing sleeve and they cut a helix angle into the bore. http://tbmracing.com/web/index.php?p...mart&Itemid=18
I know they use this in the automotive industry for throttle body spacers and such but wondered if anyone had first hand test results on such a theory?
01-06-2010, 03:11 PM #2
We have tested these types of things at the engine building shop I work at. None of them do a damn thing positive.
Simple way to explain this-
Just suppose that the incoming air does swirl when passing thru this contraption. What happens to that swirling air once it hits a divide between cylinders? As in each separate intake port. Or once ithas to make a turn in the port?
Will the swirl brake off and become many small swirls? One for each cylinder?
Answer is no. It does nothing positive.
A flow bench and a little smoke goes a long way to showing this as busted. Now where is that hot little redhead to say that?
01-06-2010, 04:48 PM #3
Great reply ! I think the hot little red head is off having a baby
01-06-2010, 05:49 PM #4
Sounds like marketing to me, but I honestly have no factual data to base that opinion on. It's just an opinion.
01-06-2010, 06:19 PM #5
I think they try to give the impression that more air is forced into the engine. Not falling for it. There are more ways to get more air that we know work.
01-06-2010, 06:39 PM #6
why cant you just machine out the intake area and not use this part?
01-06-2010, 07:01 PM #7
thats what we do on the higher boost setups, especially when the tb is bored. It doesnt work well on the stock sc/stage1 ski's. the opening track goes from 58m to 70m when removed.
When you do remove the ribbon you have to machine out the lip in the manifold.
If you are a do it "yourselfer" I recommend using a 2.3/4" hole saw and take your time.
You could also have your intake manifold extrude honed and you will notice alittle gain.
Have your head ported and the gains just keep getting better, it never stops does it?
01-07-2010, 07:19 PM #8
All kidding aside, very good info Dan. Sounds like come spring there will be a lot of fast JD boats running around my lake. Can you maybe just start turning local people away? If I start losing races I'm going to completely blame you. Just an FYI.
01-07-2010, 07:49 PM #9
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