a couple questions about stroker engines

[Goose]

I did do a search and read pretty much every topic covered under a search for stroker engines it was 6 pages of topics.it did answer a few questions now i have more

I bought a 5mm crank and cases clearenced for the crank and a 62t cylinder and it came with a spacer for the head.what i have read was im gonna want to lower the port timing half the distance i stroked the crank if i am correct?

So on 5mm i will need to cut 2.5mm off the bottom of the cylinder?just to clairify im gonna start with a stock 61x cyl.so take the sleeves out and deck the bottom to lower the port timing. and now ill have the issue of the pistons of pistons hitting the head.2 things i had in mind first was to run flat top pistons and 2nd was cut the domes and not use the spacer.

now i understand that i lowered my port timing what about the fact the the pistons travels 2.5mm higher than stock and add the fact that i lowered it already 2.5 do i need to open the ports up and raise the or are they fine where they are.

am I on the right path on this or am i way off.
im looking to end up with a 5mm stroker with bigbore northwest sleeves and flat top pistons.also any other info on this will be greatly apreciated
thanks

 

[snowxr]

I think you are looking at it the wrong way. You need to raise the entire cylinder, and put a spacer under it. Your domes can be cut to allow the piston to travel to the top of the sleeve, with the crown above the top of the sleeve.

I'm no expert on the porting for strokers, but it does make sense that once you have a 2 - 2.5mm spacer under the cylinder, you may want to lower the ports to get the proper port timing for the longer stroked crank.

Kurt

 

[robertg]

I built a 4mm stroker last year with the Northwest sleeves. I didn't use a spacer plate, I just got the domes machined. I ported the cylinder casting to match the sleeves.

 

[Goose]

I built a 4mm stroker last year with the Northwest sleeves. I didn't use a spacer plate, I just got the domes machined. I ported the cylinder casting to match the sleeves.

i did read your build thread.how did it end up running.im thinking in gonna go with them sleeves also

 

[kevbo]

Does a 4mm stroker crank actually work with stock rods and cylinders?

 

[#ZERO]

They're a few different combinations you can use with the 5mm stroker crank and a 61x or 62t cylinder.

The cheapest way would be to install your spacer head plate with the oem dome pistons and machine the plate thickness for your proper squish band clearance.

Another way would be to install a spacer between the case and cylinder for oem dome piston use, to get your desired port timing. Then machine the domes for your correct squish band clearance.

The best way would be to use the Northwest or Watcon big bore sleeves with flat top pistons and mill the bottom of the cylinder to get your port timing were you want it. Then machine the cylinder or domes very slightly for your correct squish band clearance. These sleeves work best with unported 61x cylinders but if you wanted to use your 62t cylinder you would have to weld the upper exhaust ports for the proper sleeve alignment. Both these sleeves have extended ports which make them great for 4~5mm stroker crankshafts.

If you're going to build it yourself you should purchase crankshaft degree wheel and a dial indicator TDC tool to double check you port timing with the sleeves at different heights, before any machining starts. A difference of .010" in sleeve height equals about one degree in port timing, so accuracy is very important if you're looking to make some power in the correct rpm band.

 

[SUPERTUNE]

Or.... you could just box up the long block and mail it to: TEAM SCREAM RACING
1988 Carroll St.
Clearwater, Fl. 33765
(727)442-7700
It's that simple and will keep you mind free of to many degree numbers banging all around in there...

 

[robertg]

i did read your build thread.how did it end up running.im thinking in gonna go with them sleeves also

I only had it out a few times last year but it ran really well.

 

[bad93blaster]

Or.... you could just box up the long block and mail it to: TEAM SCREAM RACING
1988 Carroll St.
Clearwater, Fl. 33765
(727)442-7700
It's that simple and will keep you mind free of to many degree numbers banging all around in there...

that sounds like the best way to me

 

[WaveDemon]

that sounds like the best way to me

it also sounds the most expensive.

 

[RoyalFlush@PCB]

it also sounds the most expensive.

That depends. :slap:

 

[robertg]

It may or may not be cheaper in the long run to get someone else to do it however what will you learn by doing that? Isn't the whole point of these forums to exchange information and learn something? We could answer most questions by saying "Take it to the dealer to fix it", but that wouldn't make very interesting reading.

 

[SUPERTUNE]

All I have to say is... do you like to ride more or be a development rider? When all you do is ride 5 minutes, work 6 hrs on ski, ride 5 mins, work on ...
Some riders would just want to have a set-up that works right from the start and basically 'a no fuss with' proven blueprint horsepower package and ride a LOT more...

 

[w-nut]

Or.... you could just box up the long block and mail it to: TEAM SCREAM RACING
1988 Carroll St.
Clearwater, Fl. 33765
(727)442-7700
It's that simple and will keep you mind free of to many degree numbers banging all around in there...

how about kawasaki motors

 

[Mark44]

y

All I have to say is... do you like to ride more or be a development rider? When all you do is ride 5 minutes, work 6 hrs on ski, ride 5 mins, work on ...
Some riders would just want to have a set-up that works right from the start and basically 'a no fuss with' proven blueprint horsepower package and ride a LOT more...

Read this XFT-Lou. LOL.................

Mark44

 

[dbrutherford]

how about kawasaki motors

X2... I am wanting a built up big pin for my ski.


And Chuckie is right... wrenching is not nearly as fun as riding!

 

[robertg]

All I have to say is... do you like to ride more or be a development rider? When all you do is ride 5 minutes, work 6 hrs on ski, ride 5 mins, work on ...
Some riders would just want to have a set-up that works right from the start and basically 'a no fuss with' proven blueprint horsepower package and ride a LOT more...

It sounds like you have seen me riding. If I rode as much as I worked on my ski I might have some riding skills.

 

[Roo]

The man has a great point. :djsmilie:

But I do like the questions being asked. It is nice to know ALL the in's and out's even if it is not you building or assembling the motor.

All I have to say is... do you like to ride more or be a development rider? When all you do is ride 5 minutes, work 6 hrs on ski, ride 5 mins, work on ...
Some riders would just want to have a set-up that works right from the start and basically 'a no fuss with' proven blueprint horsepower package and ride a LOT more...

 

[headshock]

Or.... you could just box up the long block and mail it to: TEAM SCREAM RACING
1988 Carroll St.
Clearwater, Fl. 33765
(727)442-7700
It's that simple and will keep you mind free of to many degree numbers banging all around in there...

Have a web page?

 

[Goose]

So after a few days of research i came up with this.if i use 82mm kawie flat top pistons and a stock 61x cylinder and sleeves. I will take around 1.27mm off the bottom that will set my port timing up as follows
*means degrees cause i havent figured out where that symble is on the keyboard
85*my exhaust port will open
116*my transfers will open
190 degrees exhaust duration
128 degrees intake duration
30 degree blowdown



is that an ok area to shoot for with port timing