exhaust pulse tuning modification

[powerabout]

Attachment 385023. Here's a t2x exhaust chest, u can see how the top 3 and bottom 3 are split.

what is the firing order on one of those?

[FORBESAUTO]

I still have a problem with those 2 also especially 6. It's port actually ends in the exit. If any stuffing takes place it has to happen before pulse reaches tuner due to the low pressure wave pulling it out.

[mrcrsr]

I believe it's 162435, which doesn't make alot of sense as the bottom cylinders sequence is backwards, maybe Sam will chime in.

[FORBESAUTO]

ok thats solved how about why 5&6 are different?

My guess is the scavanging is greater on 5 and 6 due to fact how close they are to the tuner, causing it to pull too much of the fuel charge out

[powerabout]

maybe after all this we will learn how an OMC v4 works

[FMP]

So 1 2 3 are 120* separate pin angle as are 4 5 6. Pairing occurs within each chest. However the scavenging effect because of the long run may influence on others because of 60* pin.

[FORBESAUTO]

Just a thought, how about it just as simple as at the end of the exh. event as the flow lowers the last bit of fuel charge that is expelled is stored in the "pocket" at end of port and when the pressure in the cylinder lowers to less than the exhaust back pressure in chest its pushed back in. Just a thought.

[FMP]

Cylinder is on compression stroke with port open

[Mark75H]

I believe it's 162435, which doesn't make alot of sense as the bottom cylinders sequence is backwards, maybe Sam will chime in.

The bottom sequence is reversed for vibration reduction. These run much smoother with a more mellow sound than a regular inline Merc. 123 over 123 must have had a really bad vibration at some speed.

[Whaaaaat]

Am I the only one whose read this thread and now can't stop thinking about getting CRT to cut a block with seperate runners, ready for manifolds to bolt 6 expansion Chambers to? 800hp with a magical musical sound!

[olboatman]

Am I the only one whose read this thread and now can't stop thinking about getting CRT to cut a block with seperate runners, ready for manifolds to bolt 6 expansion Chambers to? 800hp with a magical musical sound!

I love the sound of pipes.....BUT most don't as we found out when we tested the drag sled on the lake yrs ago....and that was with their windows closed!!!! Would like to see them run in the open drag classes though!
Gary

[BUZZIN' DOZEN]

[Whaaaaat]

Yes, that. Now in a billet block designed for it. With CPU controlled water injection to broaden the power band.

I've seen pictures around, any info on what power they got out of it? How long they got it to last? What rpm they tuned in for?

[FMP]

The bottom sequence is reversed for vibration reduction. These run much smoother with a more mellow sound than a regular inline Merc. 123 over 123 must have had a really bad vibration at some speed.

Somewhere someone has video footage showing one of those l6 cranks spinning with a strobe light timed to show deflection . It's wild how it bends.

[FMP]

Shape of ex port, square, oval football Canadian size, bridges and the area just outside the sleeve for expelling and funneling pulse in and out. If bridged, middle ports higher than outer can all effect quality of pulse.