Looper exhaust porting

[baja200merk]

Use acid for the aluminum and get a lisle style rigid hone on ebay for around $100.00

[wanagofass]

What grit do you finish with on a rigid?

[baja200merk]

I think mine are 180 and Finish with the ball then brush/soft hone

[6Killer]

Sequence.........

1 Ball
2 Rigid
3 Brush

[racer]

I agree with 6Killer on order, you need the rigid right before a brush to get proper cross hatch

[powerabout]

looks like I need to buy a finishing brush

[wanagofass]

looks like I need to buy a finishing brush

+1, what does it take to bore a 2.7l to 3.0l? Seems to be some mixed oppinions.

[Captain75]

Started to "clean up the rodslots" today.. Do you guys recommend anything else besides the grinding I've aleady done, shown in the picture? (Dont dare to grind deeper due to thin material.
Do I have anything to gain by grinding a shallow slot towards the boostport, shown in picture?

[Captain75]

To the top...

[olboatman]

Captain75 By cleaning up the rod slots are you smoothing out the rough casting? Keep up the GREAT posting of pics --- Great info. Gary

[Captain75]

Captain75 By cleaning up the rod slots are you smoothing out the rough casting? Keep up the GREAT posting of pics --- Great info. Gary

yes I'm trying to remove all the rough casting and sharp bends(shown in the other crankcase picture) I'm still a bit abivalent weather I should feed the boostport directly from the crankcase entrance or not. You could easily improve the flow by removing the lower sharp edge on boostport lower feeding window and thereby allow some of the freshcharge to direct enter the transferduct(the edge I'm pointing at with the file in earlier picture)

[6Killer]

The bigger "bang for your buck" would be to add finger ports. The 2.7 has plenty of meat for doing that.

[baja200merk]

The bigger "bang for your buck" would be to add finger ports. The 2.7 has plenty of meat for doing that.

Is there an echo in here

If you do the rod slot like that you better take some time to stuff the crank case. The more you remove the more you need to fill. There is not much meat on the 2.7 in that area (atleast compared to newer blocks) and your not looking to turn it 9k.

[Captain75]

Is there an echo in here

If you do the rod slot like that you better take some time to stuff the crank case. The more you remove the more you need to fill. There is not much meat on the 2.7 in that area (atleast compared to newer blocks) and your not looking to turn it 9k.

My boat is mainly used for skiing and tubing and I don't want to raise the powerband

[6Killer]

Fingers will add torque across the board.

If you are not proficient at tuning, all your mods will be a waste......