exhaust gains ?

**jmr112** · 11-11-2003, 01:05 PM

Hi guys!

As my motor is all apart and i have all the winter to work on it, i began a little job on exhaust chest along with exhaust plate and tuner matching. After that, can i get some benefits from removing the exhaust liner without drilling the mid section.

Thank's Jean Martin

**Dave S** · 11-11-2003, 07:03 PM

Raceman is asleep. We need a tuner and drilled holes to awake him.

I take a rat tail file and smooth the edge on the top of the exhaust ports, where it bends from the ex port to the ex chest. Not at the port. Pullin the can will make all the 4 strokers envious.Or piss them off because they spent all tha $$$ for a quiet motor and then you came and woke them up.

**T-REX** · 11-11-2003, 09:08 PM

Tha cutt'in ov tha exhaust chest won't make HP!!!...It will allow your motor to expend exhaust gas that U have burned from inhance'in fuel delivery...Dragg'in down ya ports and then stuff'in tha back wit tha 2.0 cover will inhance ya midrange/top end sum...Matching adaptor/tuner iz good...how much?? good question, dependz on other mods made to motor...Tuner???...bout all I kin say witout gitt'in nailed by Raceman iz, LONG keepz torque @ lower RPM, SHORT moves ya peek torque in tha upper RPM range...which iz better?? Wher do U want ya peek torque??...

Opening tha down house'in...dependz on tha geercase used...If U juss remove tha can and open holes wit a stock "big" geer case, all U gunna see iz noise, and possably a loss ov bottom end, because U are remove'in tha exhaust from around tha prop, so it bites harder, and U loose back preasure which az we know, IZ bottom end grunt for a O/B...If U have a CLE, then opening tha down house'in will help ya motor, kuz tha cle haz a bigger brg carrier and less room for exhaust exit...so U need tha releese to equal a large geer case...Merc sent out a bulletin to drill 4 -1" holes in tha CLE to equal tha large L/U.....REX

**jmr112** · 11-11-2003, 10:06 PM

thank's for inputs.

Rex, where mercury suggest to make the holes on the CLE that's what i run.

**Raceman** · 11-11-2003, 10:14 PM

ZZZZZZZZZZZZZZZZZZZZZZZZ

**Dave S** · 11-11-2003, 10:49 PM

ZZZZZZZ

**T-REX** · 11-12-2003, 09:32 AM

Tha holes are actually 1 1/4" instead ov 1"...I used 1" in my XR-6 geercase when I wuz look'in for sum more top end(made NO differnce, but down house'in iz already open)...Drill 2 holes on each side, in tha exhaust open'in..Leeve 1/2" between them(@ closest point)...Tha geercase iz quite thick here, so git a good hole saw, and keep spray'in it wit wd-40 or sum type ov thin oil to cool tha cutter...This iz a good time for a buddy to be hang'in around, and doin tha spray'in!!...I wouldn't recomend take'in ya hand off a 1/2" drill wit a hole saw on it!!!...Good luck

Now If'in ya want ta bolt on bout 50HP, U need to git Raceman ta sell ya one ov hiz secret tunerz...I thank he haz bought all ov'em up, cuz they ain't no HP makerz leff

...REX

**ProComp** · 11-12-2003, 02:03 PM

Is this what your talking about?

ProComp

**T-REX** · 11-12-2003, 07:28 PM

Datz exzatly what I'm talk'in bout!!..I see U threaded yours, good move...I juss drilled a 1/4" X 20 hole in between tha exhaust holes, and bolted a plate over mine...REX

**jmr112** · 11-12-2003, 09:52 PM

That s what i want to see, this way you dont have to remove the liner, and it will be less noisy at the dock,right?

And whit the threaded holes you can go whit wife and nothing will SCREAM .

Good advice thank s boys

**ProComp** · 11-12-2003, 10:27 PM

In my opinion your idle with improve, it is hardly noticeable at idle (at the dock) and sounds great when your flying. If you don't like it, put the plugs back in.

If ya want to buy some plugs I'll sell ya mine as they have never been put it!

Do it.

ProComp