Jump to content

Recommended Posts

Posted (edited)

Hey guys, I'm interested in buying a pair of cylinder heads that have been supposedly mx ported for a 4mm stroker engine. In the cylinder intake ports, the guy who ported the cylinders wrote his name "Billy Winn". I'm hoping that someone on here knows who this guy is and what company he works for. If i find this out, i can call that company and give them the numbers they inscribed underneath the cylinder jugs which i believe is their order # or purchase order # and hopefully find out some details on the work they had done on them. Any help would be appreciated guys. Thanks!

 

 

Oh i totally forgot to mention this, but these cylinders came off a engine that used the spacer plate underneath them. Is this a dead give away that they are not ported for a 4mm crank? And also is there any way to identify a 4mm port job? Measuring or???

Edited by afireblade929
Posted

The spacer is a pretty good giveaway that they are not ported for the 4 mil. Take a measurement from the deck to the floor of the exhaust port, stock is @55mm 4mil should be @57mm.

Posted

i'd say get a set of cylinders ported so you don't have to use the spacer plate.i found that kevin herr has the best prices and the beast to deal with around.do a search

Posted
The spacer is a pretty good giveaway that they are not ported for the 4 mil. Take a measurement from the deck to the floor of the exhaust port, stock is @55mm 4mil should be @57mm.

 

Ok thanks, thats a big help. Is the exhaust the most important or should the floor of the intake be 2mm lower than stock to? Since the floor of the exhaust is 2mm lower, should the roof of the exhaust port be 2mm higher?

Posted
Ok thanks, thats a big help. Is the exhaust the most important or should the floor of the intake be 2mm lower than stock to? Since the floor of the exhaust is 2mm lower, should the roof of the exhaust port be 2mm higher?

the floors of the transfers should also be 2mm lower. For a 4 mil mx port the roof of the exshaust should not be raised much. If the exhaust has been raised 2mm on a 4mil port it would be more of a dune type port.

Posted

It should actually be 54mm to BDC not 55. As well with the transfers. And just using a spacer plate is not a dead give away that its not ported for the stroke. I run a spacer on my trex engine.

Posted
It should actually be 54mm to BDC not 55. As well with the transfers. And just using a spacer plate is not a dead give away that its not ported for the stroke. I run a spacer on my trex engine.

OK OK, it's acctually 54.9mm...measured a set of virgin stockers to get that # the floor of the ports sits slightly below the crown of the piston and on a 4mil stock cylinder bike (with an MX port) I would say the plate is a pretty good indication they are not ported for the stroke. Raise the cylinder 2mm and you would have to drop the floors 4mm to compensate for the stroke, that would put you at way more duration than an MX port. I said pretty good not dead giveaway. I personally don't know why you would want to run the spacer and port the floors that much lower,one more place for an air leak IMO. Maybe you could explain. :shrug:

Posted

Thats such a big help slobanshee, you really know what your talking about and i appreciate you taking time to measure a stock set of cylinders for this topic. I also appreciate everyone who put in their 2 cents to help me out on this. Thanks Guys!

Posted
Here is what the intakes look like on my Drag Ported 4 mill cylinders. You can see the intakes have been lowered down. These are ported to run no spacer plate.

PatriotRacingIntakePorts.jpg

 

That a good looking port job. Was it sand or media blasted in the intake? Who ported these cylinders for you?

Posted

That is how ONE builders 4 mil port looks (and Patriot is a great builder, no doubt...) but you can not go by how a port "looks" to tell how it's going to run.

 

The size and shape of the holes is where the money is. It's called port timing, how and when each opens in relation to piston travel, on top of their shape and size.... You could have a "pretty looking" set of cylinders go dog slow, and a Stevie Wonder set run like a raped ape....

 

Not aimed towards you...Jbook, but a lot of people post pics of the intakes ground up on the net and say how does my port job look? It does NOT matter how it looks, it matters how it runs....period.

Posted
That is how ONE builders 4 mil port looks (and Patriot is a great builder, no doubt...) but you can not go by how a port "looks" to tell how it's going to run.

 

The size and shape of the holes is where the money is. It's called port timing, how and when each opens in relation to piston travel, on top of their shape and size.... You could have a "pretty looking" set of cylinders go dog slow, and a Stevie Wonder set run like a raped ape....

 

Not aimed towards you...Jbook, but a lot of people post pics of the intakes ground up on the net and say how does my port job look? It does NOT matter how it looks, it matters how it runs....period.

 

No problem. I was just trying to show him a pic of the intakes lowered down 2mm for the 4mill crank.

 

But like dajogejr said you cant tell how it is going to run by pic's

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...