927cc 66v/e motor build

[RiverRat]

Building my 927cc motor for the X-jet. My Lamey PV motor was rocking until my manifold crapped out on me. I was going to continue to run that set up but can't deny the numbers that the 66e (gp800) produces.

For this build I am using 66v cylinders off a gp1200. I have not done the port mapping of this cylinder but have been told by several people that the port timing is better for low end performance. Jeff from Waterdawgs is providing the cylinders........all media blasted, bored to 87mm and re-nikacil plated cylinders. The nikacil plated cylinder promote better and more uniform cooling while also improving piston acceleration over steel sleeved cylinders. The pistons will be forged wiesco that are lighter and more durable than cast pistons.

More info and pics will follow soon...............

 

[RiverRat]

:smoker: Motor specs as of now:

66v bigbore cylinders
Forged pistons
Waterdawg billit girdled o-ring head
Waterdawg billit intake manifold
R&D reed stuffers
Dual 49mm full spec carbs
MSD TL ignition

I am working on removing a few cast marks on the cases and clearencing one section for the larger pistons. Once finished I will have them blasted on the inside to give a uniform textured finish. The 66e cases do not need to be ported. All I am going to do is smooth out some sharp edges and it will be good to go.

 

[SuperJETT]

What's your plan on the pump, TBM cone/mag prop first?

 

[SuperJETT]

BTW, use the new gallery, some very cool features if you use it.

 

[RiverRat]

What's your plan on the pump, TBM cone/mag prop first?

Yeah, I am going to see what I can get by with on the TBM first. I should be able to get a different pitch mag impeller and it should be fine.

 

[superramjet]

theres a lip on the opposite side of the intake, your sleeves will hit them, remove it. Notice how when the reeds are in the case they block the boost port, run a spacer to pull them out of the way

 

[2nd nature]

what kind of horsepower will it make after porting?

 

[SuperJETT]

what kind of horsepower will it make after porting?

Who cares, think of the torque!

 

[joesuperjet]

theres a lip on the opposite side of the intake, your sleeves will hit them, remove it. Notice how when the reeds are in the case they block the boost port, run a spacer to pull them out of the way

Lol - I like the new Dyno you have!!!!! :Banane35:

JAM

 

[RiverRat]

some case work.........still working on shaping.

I am pretty much doing the same benificial thing people do to 62t cases. Smoothing out hard edges and roughing up the surface for better fuel atomization. I also plan to mark and drill holes in the reed stops. That way they are still finctional but less restrictive. Notice how they block access to the boost port. I could just install a reed spacer plate but have heard that these motors do not take well to increased case volume. 12mm reed spacer coupled with the dimentions of the reed mounting area can add a significant amount of volume to the case, not to mention anouther 12mm to the intake track. Both values I want to minimize

 

[keefer]

Man that is sweet, I have been wanting to build a 66e platform engine for some time. I was talking with Jeff today and he had me stoked about building a 950ish setup. Maybe someday!! Keep the pictures coming..

 

[ROTATION]

You are getting the case volume thing wrong. The increased bore will increase crankcase compression, which raises speed through the transfers causing the crankcase to be over-scavanged at low speeds. Longer intake will also increase low speed torque.

 

[RiverRat]

You are getting the case volume thing wrong. The increased bore will increase crankcase compression, which raises speed through the transfers causing the crankcase to be over-scavanged at low speeds. Longer intake will also increase low speed torque.

I will keep that in mind. I plan on checking a variety of set ups on this motor.

 

[waxhead]

Rotation is right
crankcase stuffing is old old old school
it makes for peaky engines

i would be looking at running reed spacer if i was you

 

[inchadeboca]

riverrat, I recently rebuilt my 66e and i was told not to use the wiseco piston because they expand too much and it would cause a problem on the nikasil bore. so i put in oem matched pistons. can u explain......

 

[RiverRat]

riverrat, I recently rebuilt my 66e and i was told not to use the wiseco piston because they expand too much and it would cause a problem on the nikasil bore. so i put in oem matched pistons. can u explain......

Nope.....I can't expalin that. My only theroy is that the forged aluminum piston and cast aluminum cylinder expand at different rates, potentially causing a piston seizure or cylinder scoring. I would think that the piston has to expand by a significant margin to do that kind of damage.

 

[Waterdawg Kustomz]

riverrat, I recently rebuilt my 66e and i was told not to use the wiseco piston because they expand too much and it would cause a problem on the nikasil bore. so i put in oem matched pistons. can u explain......

There is absolutely NO problem using the Wiseco pistons. If the clearances are right, then they will run for a very long time. Wiseco builds all our pistons, even the 98mm, and we have no problems with them. A forged piston will expand quicker, but if you build the motor knowing that, everything will be OK. :thewave::bananalama::Banane19::bigok:

Jeff

 

[Mile9c1]

I think with the forged pistons you just have to run more clearance and let them warm up properly... I've used Weisco's in my dirtbikes w/plated cylinders, no problems.

 

[sambeno]

what pipe are you going to use?

 

[RiverRat]

what pipe are you going to use?

I may try and run the EME dry pipe chamber with the waterdawg manifold.