20xd repower

[Blazer]

So I have bought an 20xd that had no motor and I’m thinking of slapping my fully built 2002 yamaha vmax 200 hpdi on it any thoughts or suggestions maybe some insight on possible top speed?

[21XDC]

I'm guessing 75ish

[gehol]

Maybe 75ish, my guess is low 70's. The lower unit is going to hurt the 20. Generally need to run prop to be surface piercing to get best speed. Typically the center line of prop is 1-1/4 to 1-3/4 inches above pad on the 20's. Need low water pickup for that.

[Blazer]

I figured it would be faster than that honestly I have a 1991 blazer vlx200 that it is coming off of and it pushes the blazer to 78 mph gps verified and it was not redlined I do want to get my lower unit coned so I can pick her up a lil bit more

[gehol]

With a quality cone job I would think upper 70's possible.

[hyperflow]

The stock Hpdi gear case with VERY minor mod can run 1/2" above pad. You can mod the stock plastic water pickup with JB water weld.

When you say full mod im assuming your talking about a phase 3 kit? I have no experience with a phase 3 200 hpdi but i would think it would run same as a stock 250hpdi.

My 20XD with a box stock 250 hpdi ran 85mph 2 guys loaded to fish. With a Phase 1 kit i ran 88mph, phase 3 kit i ran 95+.

[Blazer]

Phase 3 kit also some port timing work block was back welded then hogged again for clearance high comp pistons and a lil clearencing at the bottom of the cylinders to clear the rods also has lightweight flywheel balanced and blueprinted has velocity stacks also I am trying to figure out my way into the computer now so I can play with the good stuff

[hyperflow]

Phase 3 kit also some port timing work block was back welded then hogged again for clearance high comp pistons and a lil clearencing at the bottom of the cylinders to clear the rods also has lightweight flywheel balanced and blueprinted has velocity stacks also I am trying to figure out my way into the computer now so I can play with the good stuff

Just some advice, not sure if it relates to the 2.6L. But on my 3.3L V-stacks was exactly 1mph slower then running open TB. Also magic compression on the 3.3L was 130psi, I went all the way up to 150psi. I gained bottom end and lost topend at 150psi and needed good fuel. with 91 oct i had detonation.

[Blazer]

I appreciate all the help guys I’m headed home to see what she will do I will keep y’all posted and yeah I have to run real good fuel actually I have to run c16 vp race fuel and mix it a lil less than 50:1 I don’t wanna meet this peach