64x ported 4 freestyle????

[Big Kahuna]

you need to ride a race boat.... you hit the gas and it really does not do anything until the RPM's really start to get up there, like a lag almost...... rarely do you find a race motor that hits hard off the bottom and pulls and still has wicked fast top end. That is the difference between bottom end vs top end.

another way to describe it is if you go into a turn like around a bouy, with a boat with gobs of bottom end, when you hit the gas it immediately rips your arms off, with top end, you have to hit the turn much faster and get on the gas sooner so you can accelerate away from the turn...

 

[Mouthfulloflake]

I have ridden boats like that.

IM saying, I cant imagine power being really useable below 3000rpms anyway?

they go from 0-7000 rpms in a fraction of a second any right?

I dont understand how its better to make power from 1500 or 3000 with a snap like that?

you need to ride a race boat.... you hit the gas and it really does not do anything until the RPM's really start to get up there, like a lag almost...... rarely do you find a race motor that hits hard off the bottom and pulls and still has wicked fast top end. That is the difference between bottom end vs top end.

another way to describe it is if you go into a turn like around a bouy, with a boat with gobs of bottom end, when you hit the gas it immediately rips your arms off, with top end, you have to hit the turn much faster and get on the gas sooner so you can accelerate away from the turn...

 

[Matt_E]

I talked to Paul this am-he gets a 61x cylinder to come alive at 1800rpm/ he can only get the 64x cylinder to come alive at 3000-3500rpm. Sounds like a 62t and 64x is not for me.

That doesn't make much sense to me.

 

[Idok]

That doesn't make much sense to me.

they are probably dyno figures :27:





Gil...for flatwater freestyle not goinmg to be the BEST choice..at least without a bunch of machinework..

but it'd make a WICKED surf motor....


you build it, Ill give ya a 100 bucks and we both profit :Banane26::cool2:

 

[Mouthfulloflake]

Hey IDOK,

that makes me wonder something...

what differentiates a surf VS flat motor?

they are probably dyno figures :27:





Gil...for flatwater freestyle not goinmg to be the BEST choice..at least without a bunch of machinework..

but it'd make a WICKED surf motor....


you build it, Ill give ya a 100 bucks and we both profit :Banane26::cool2:

 

[Goose]

how much would you need to take off the bottom to lower the port timing to get it close to a 61x?with a stock stroke you could run it as a pop top like if it were a stroker

 

[WaveDemon]

Hey IDOK,

that makes me wonder something...

what differentiates a surf VS flat motor?

IMO the ski speed when you get to the hit.
barely moving = flat
at or above plain = surf

 

[Matt_E]

Supposedly, with increasing bore the 760 cylinder will have port opening numbers very close to a 61X cylinder - because the port roofs are angled downward, so an increasing bore will lower the roofs.

 

[Matt_E]

IMO the ski speed when you get to the hit.
barely moving = flat
at or above plain = surf

I ride flat predominantly, and I don't find myself in situations where I am barely moving very much.

Of course, I suck.

 

[WaveDemon]

I ride flat predominantly, and I don't find myself in situations where I am barely moving very much.

Of course, I suck.

ok, how about hit while not on plain. my ported 64x cylinder hits a few mph above plain. I doubt flat water guys want that.

 

[Mouthfulloflake]

there is supposedly 2mm or less difference between the deck to port height.

base gasket can get a good portion of that.

how much would you need to take off the bottom to lower the port timing to get it close to a 61x?with a stock stroke you could run it as a pop top like if it were a stroker

 

[Mouthfulloflake]

ok THAT I can relate to.

I always just put up to a wave, and then hammer it in the trough ( spelling?)

ok, how about hit while not on plain. my ported 64x cylinder hits a few mph above plain. I doubt flat water guys want that.

 

[ketsair]

ok THAT I can relate to.

I always just put up to a wave, and then hammer it in the trough ( spelling?)

lol, not me, keep'er pinned & prehop, lol, as you know, my ski don't hookup, i have to keep my momentum...hahahaha

 

[Mouthfulloflake]

the difference, is that my pump/impeller actually WORK.

haha

lol, not me, keep'er pinned & prehop, lol, as you know, my ski don't hookup, i have to keep my momentum...hahahaha

 

[ketsair]

the difference, is that my pump/impeller actually WORK.

haha

dirty...dirty whore....:kabong:

 

[Mouthfulloflake]

Hey! that violin looks like mine!

 

[Goose]

if your goin into a flatwater roll if you carry some speed into it is gonna help with rotation so havin the power up in the rpms mite not be a bad thing in that situation.I run a factory dry pipe cause i like where it brings the power in at

 

[Matt_E]

ok, how about hit while not on plain. my ported 64x cylinder hits a few mph above plain. I doubt flat water guys want that.

My primary ride has always been a ported 61X cylinder, on T cases.

Last year I built a ported Frankenstein motor for my second SJ.

While there is a small bit of difference in where they hit, it is not as dramatic as you describe.

Two things to keep in mind here:
1 My porting is done by me. That may account for lacking hit of the 61X cylinder. :dunno:
2. I don't do much below planing speed.

 

[Matt_E]

if your goin into a flatwater roll if you carry some speed into it is gonna help with rotation so havin the power up in the rpms mite not be a bad thing in that situation.I run a factory dry pipe cause i like where it brings the power in at

Exactly.

 

[Big Kahuna]

one of my problems with rolling has been approaching the wave too slow....... I worked on that the few times I rode this year, even to the point that I got better rolls the one time I competed on a bone stock, untuned 701 motor. Carry more speed. So, a 760 motor ported really might not be that bad, almost makes me want to get Paul to port my motor that I cannot sell and just run it.