CRT motor on display this weekend in Jasper, 1st start up!

**powerabout** · 10-12-2016, 09:51 AM

thats what I was thinking packaging all that around a merc 2.5 case doesnt allow much transfer or exhaust passage size?
I didnt know people were drag racing 4" bore 2.5's was that with steel sleeves in HI PO blocks 1/4" overbore?
Cant beat the old no replacement for displacement matra.

**baja200merk** · 10-12-2016, 11:37 AM

I thought The 3.5 is roughly based on the 3.0 Merc block which with a 3.2 crank and big bores comes out to 3.6l. They don't like the stroke of the 3.2 crank it doesn't complement the rpm they are aiming for. There are also some Omc bearing sizes in the plan.

**powerabout** · 10-12-2016, 11:47 AM

That would sound more realistic with 4" bore and 2.5 stock stroke, still thats a big piston to throw around at 10k,maybe its a mix of the 2 to get 3.5ltr?

omc f1 v8 has smaller bearings than stock looper , its actually xflow sizes for big and small end, 10k all day!! ( well the 3.0 version could and the rods a huge)
of course 2 extra pistons mean they can be smaller

**baja200merk** · 10-12-2016, 12:05 PM

I know he said they were 4" bore but I don't remember the stroke (too much shine I guess). It's in the right hands no doubt it's gonna be a monster.

**90 5.0** · 10-12-2016, 12:45 PM

Originally Posted by powerabout

That would sound more realistic with 4" bore and 2.5 stock stroke, still thats a big piston to throw around at 10k,maybe its a mix of the 2 to get 3.5ltr?

omc f1 v8 has smaller bearings than stock looper , its actually xflow sizes for big and small end, 10k all day!! ( well the 3.0 version could and the rods a huge)
of course 2 extra pistons mean they can be smaller

We were throwing 4.25" Pistons @ 10k on motor cars over 10 years ago in NMRA, should be easier for a 6cyl 2 stroke with a shorter stroke.

**patchesII** · 10-13-2016, 09:03 PM

The 3.5 is basically a scaled up Drag motor. Shares nothing with Mercury's 3.2

**caldwellrace** · 10-13-2016, 10:46 PM

The stroke is 2.865" X 4" with a 6.5" rod for the 3.5 ,

we will offer a 3.100" X 4.125" bore with a 6.5 to 6.8 rod for a lower RMP application option 4.0 Lt.

The block was designed to grow in CI's for future ventures

**powerabout** · 10-13-2016, 10:48 PM

Originally Posted by caldwellrace

The stroke is 2.865" X 4" with a 6.5" rod for the 3.5 ,

we will offer a 3.100" X 4.125" bore with a 6.5 to 6.8 rod for a lower RMP application option 4.0 Lt.

The block was designed to grow in CI's for future ventures

awesome!