My home ported 6m6

[Stukas]

After being on the water and watching the magoo guys ride this past sunday, ive decided i need more power...haha, so after hours of reading, i began porting my 6m6 cylinder since i am too poor to go up to a 701, or pay someone to port my cylinder...i have yet to do any work onthe transfer ports, and i honestly dont know if i am going to, just cause im anxious to see what opening up the exhaust ports did for power, the stock ones were about 50% of the bore dia. i opened them up to about 68%

On the front, intake side of the sleeve, after some reading i decided to remove some material, but retain most for the bottom end punch i want for freestyle, see the pics for what i came up with.

Please, feel free to critique

 

[Wolf Child]

I could be wrong here... ( it's been known to happen)


But I hope you didnt just trash your cylinders. Unless you have a flow bench theres no way to know what your going to get as a final result. this could make tuning, amongst other things, completely impossible.

JMHO.

 

[meatball]

did you use a template kit?

 

[DaUpJetSkier]

when you gonna get it back on the water, im anxious to see the result. Im glad to see people breaking into their motors, the only way to learn is to try and maybe something does get frucked up, oh well its a 6m6, always room for a 61x. Ive blown a few 550s during rebuilds, but ive learned what i did wrong and wont do it again. porting is something i havent gotten into yet.

 

[Jr.]

Wow, didn't think we made that kind of an impression!!

If you would like to meet before you reassmble, feel free to get in touch & I'll give you the skinny on your home brew porting.

I'll even hook you up with a free Hone for your efforts !!

ski ya, Paul

 

[Matt_E]

I could be wrong here... ( it's been known to happen)


But I hope you didnt just trash your cylinders. Unless you have a flow bench theres no way to know what your going to get as a final result. this could make tuning, amongst other things, completely impossible.

JMHO.

I am taking a guess here....but I have ported a few cylinders myself. Widening those exhaust ports will do nothing but good for the motor.
And as long as both ports are equal in size, tuning will not be a headache.

Widening the exhausts on a 650 basically makes it a small-bore 61x cylinder with slightly lower port timing and smaller transfer port area.

Fark, that cylinder can be had for under a hundred bucks used. What's the loss if it did go south?

 

[Freestyleriverrat]

All I have to say is Magoo ported 701 and 62T cases. I am lovin mine at the moment. Trust me, I went from a groupK ported 6m6 to this 701 and absoulutly love it. can't get that out of a 6m6.

 

[Matt_E]

The difference in power may be substantial, but so is the disparity in price. The increase in power in that 6M6 is free.

After all, an 8mm PV Lamey kicks your motor's ass, but there's a price tag on everything.

 

[Freestyleriverrat]

The increase in power in that 6M6 is free.

If it is not free that $$ is better spent on even a stock 701, or do mods on the 650 that work on a 701 as well.

 

[Stukas]

Wow, didn't think we made that kind of an impression!!

If you would like to meet before you reassmble, feel free to get in touch & I'll give you the skinny on your home brew porting.

ski ya, Paul

haha...well watching you guys, plus the fact that my old boat was a pjs 800 big bore powered 750sx, the 6m6 is very VERY slow...plus, I'm a hot-rodder, I can't leave anything stock for long... this is my real hobby... http://www.cardomain.com/ride/2108416/1

That Camaro is about 14 months of work, all made in my garage

Matt E

I agree completely...this cost me about $5 in sanding drums, and the gaskets to re-assemble...i know its not anywhere near as good as some professional porting, but im hopeing its better than stock. Another reason i want to stay away from the transfer ports its cause i want to see these results, and then go from there if im going to port more.

 

[Matt_E]

If it is not free that $$ is better spent on even a stock 701, or do mods on the 650 that work on a 701 as well.

:smile: 100% correct my friend.

As a side note, I am porting a 6M6 for a friend right now.

 

[Freestyleriverrat]

After all, an 8mm PV Lamey kicks your motor's ass,

That is what I am hoping, I have a 85mm kawi flat top piston, ported lamy pv cylinder on my desk :biggrin: but that is for next season :cool2:

Research the porting as well. My 6m6 was ported for mid to top end power and was really not suited for freestyle riding.

 

[Matt_E]

haha...well watching you guys, plus the fact that my old boat was a pjs 800 big bore powered 750sx, the 6m6 is very VERY slow.

Matt E

I agree completely...this cost me about $5 in sanding drums, and the gaskets to re-assemble...i know its not anywhere near as good as some professional porting, but im hopeing its better than stock. Another reason i want to stay away from the transfer ports its cause i want to see these results, and then go from there if im going to port more.

I am not sure, as I have looked at only one 6M6 cylinder up close (and several 61X)...but the transfer port lineup on the 6M6 looks WORLDS better than on the 61x's I've looked at.
So, if the sleeves match the casting, you'd do well to just leave them alone.
And watch it with the exhaust port width - the port jacket (which separates it from the cooling passage) isn't nearly as wide as the bigger cylinders.

 

[Matt_E]

That is what I am hoping, I have a 85mm kawi flat top piston, ported lamy pv cylinder on my desk :biggrin: but that is for next season :cool2:

OMG...How can you stand to wait? :biggthumpup:
What is wrong with you???

 

[Stukas]

did you use a template kit?

I made my own template after reading Matt E's article on home porting, and all other posts i could find on it. Like i said, its about 68% of my 76mm bore Dia. just widening and matching the sleeve to the port on the top side. Overall heigh of the port itself was not changed. Ill get it back in the water by this weekend if i can, ill let yall know what i find out

 

[Freestyleriverrat]

That Camaro is about 14 months of work, all made in my garage

.

We have similar rides but I think yours has more hp than mine. I am sitting at about 370hp.

 

[Freestyleriverrat]

OMG...How can you stand to wait? :biggthumpup:
What is wrong with you???

My magoo cylinder is brand new. I have to ride it at least a season. Plus I have to do like 500 bucks in mods to the b-pipe to clear the pv's.

sorry :hijacked: over

 

[Stukas]

I am not sure, as I have looked at only one 6M6 cylinder up close (and several 61X)...but the transfer port lineup on the 6M6 looks WORLDS better than on the 61x's I've looked at.
So, if the sleeves match the casting, you'd do well to just leave them alone.
And watch it with the exhaust port width - the port jacket (which separates it from the cooling passage) isn't nearly as wide as the bigger cylinders.

Ive never seen a 61x, but the lineup isnt anywhere where it should be ideally, and i noticed the smaller port jacket, thats why i stayed at a max width of 68%, and its only that wide in the widest spots

 

[Matt_E]

Huh....maybe the 6M6 I got is an exception. I plan to do another one over the winter, then I got a comparison.

Anyways...I would carefully (CAREFULLY!!!) match the casting to sleeve, without changing roof angle.
Remember to chamfer.

 

[romack991]

congrats, its a great feeling to know you did the work to your engine isnt it?:smile:

to discuss the porting, I think its conservative as longs as you paid attention to the wall thicknesses. you have very large radius on the top which should prevent ring snag and i would think 68% is a pretty safe width.

things i think may help it, it looks like you mainly widened the bottom. most of the benifit is having the top wide, so as soon as the port opens, you are getting the most efficency you can out of the width. (keeping in mind the wider and smaller radii you have, more prone to rings catching) which brings up chamfers, make sure you have a nice chamfer around the port. intake looks ok, you should gain some mid and top hit and rev quicker with the expense of some bottom end hit. can't comment a lot due to the fact i didnt mod that part of the sleeve. transfers if you do them, a safe bet should be to match the casting to the sleeve, leave the roof angle the same. while its apart, match the exhaust and intake manifolds.


i dont know, i've only done one cylinder so far but that'd be my .02:biggthumpup: