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Posted

I have a Hotrods +4mm crank. +5mm longer rods. Just ordered a Noss head with stroker domes (10% discount from HQ). Wiseco 795 Pistons. Am I missing anything else? I keep reading about the port timing being off. I prefer not to use the 2mm base plate.

 

Do the pistons compenstate for the timing being off? If not who can fix and how much?

 

Thanks.

Posted

Now if I understand it right.

 

4mm longer stroke (2mm each way)

5 mm longer rods

The 795 pistons have the wrist pin relocated 5mm up to compenstate for the rods.

 

So, I am thinking that the piston (depending on the dome shape) will be maybe 2mm our of the hole (head). Therefore, I have the stroker domes to protect for that. What am I missing?

 

I know the plate was the older way to before the stroked domes were popular. Id I move the jugs up 2mm, whats the point of the stroked domes? Just trying to understand.

Posted

If you have the Stroker Domes you do not use the plate. The domes are cut to compensate for the added 2mm stroke. You should have your jugs ported to compensate for the stroke , your port timings are now off. Without the port work it will run worse than it did before you put the crank in.

Posted
Now if I understand it right.

 

4mm longer stroke (2mm each way)

5 mm longer rods

The 795 pistons have the wrist pin relocated 5mm up to compenstate for the rods.

 

So, I am thinking that the piston (depending on the dome shape) will be maybe 2mm our of the hole (head). Therefore, I have the stroker domes to protect for that. What am I missing?

 

I know the plate was the older way to before the stroked domes were popular. Id I move the jugs up 2mm, whats the point of the stroked domes? Just trying to understand.

 

 

You are correct, about the pistons, and rods, but since the wrist pin in the piston is only moved up 5mm, to make up for the longer rod, you still need something to keep the added stroke of the crank from shoving the pistons into the head. Therefore, you either have to run the 2mm stroker plate, or have your domes cut, and you chose to have the domes cut, but this causes your port timings to be off. Now you need to have it ported, so that the port timings are correct, in order to get the full benefit of the stroker crank. You can run it with the port timings as they are now, but you won't get the full benefits of the stroker crank. With a stroker crank, the piston top will be 2mm higher at TDC, and 2mm lower at BDC. Hope this answers all of your questions.

Posted
Now if I understand it right.

 

4mm longer stroke (2mm each way)

5 mm longer rods

The 795 pistons have the wrist pin relocated 5mm up to compenstate for the rods.

 

So, I am thinking that the piston (depending on the dome shape) will be maybe 2mm our of the hole (head). Therefore, I have the stroker domes to protect for that. What am I missing?

 

I know the plate was the older way to before the stroked domes were popular. Id I move the jugs up 2mm, whats the point of the stroked domes? Just trying to understand.

 

If you do not raise the jugs 2mm, the port timing will be off (reduced?) by 2mm which is a lot! Think of it this way if you have the spacers under the jugs then turn the crank until the exhaust port is just starting to open then were to take the spacers out the jugs would be lowered and the exhaust port would be closed for another 2mm of piston travel, same for the transfers. The ports need to be open for the correct length of time for the exhaust gas to get out (size also matters but we won't get into that) same for the intakes if they are not open long enough the performance will suffer. (This is also expansion chamber and RPM range dependent, but I am assuming you are not planning on doing something unusual here.

 

Your performance will be notably less then the same set up ported (if you just raise the jugs 2mm there will still be 2mm at the bottom of your stroke that could be used for port area). It is kind of like putting a big motor, 4-stroke world, under a small valved head.

 

 

Ban

Posted

i would get a plate.. i'm not sure what the fus is about another place to leak.. the plate is not much diff then a gasket.. so how is there another place to leak??? you either run a gasket or a plate.. bothave same contacts on the motor.. bottom of cyls and top of cases...

Posted
i would get a plate.. i'm not sure what the fus is about another place to leak.. the plate is not much diff then a gasket.. so how is there another place to leak??? you either run a gasket or a plate.. bothave same contacts on the motor.. bottom of cyls and top of cases...

 

When running without the plate, you only have one place to put a base gasket, and that's between the cylinder, and the case, but with a stroker plate, you need two. One between the plate, and cylinder, and the other between the plate, and the case. That's what the fuss is all about, just one more place, to have an air leak. :down:

Posted

Depends on how fast you want them back. You're in peak season...so, it's probably gonna take a while.

 

I like Jeff @ FAST. He's severely backed up. Jim at Passion is another favorite around here.

 

However....

Since you're from Michigan, hit up R&B racing. I've seen some of Bob's port work...and it's pretty good and WAY hard to beat for the price. Helluva nice guy, too. I rode a bike with his porting, and it was impressive.

 

You can PM him here, machwon is his name.

 

Or call him @ 517-388-3662

 

I think he's in the Lansing area....or so.

Posted
Depends on how fast you want them back. You're in peak season...so, it's probably gonna take a while.

 

I like Jeff @ FAST. He's severely backed up. Jim at Passion is another favorite around here.

 

However....

Since you're from Michigan, hit up R&B racing. I've seen some of Bob's port work...and it's pretty good and WAY hard to beat for the price. Helluva nice guy, too. I rode a bike with his porting, and it was impressive.

 

You can PM him here, machwon is his name.

 

Or call him @ 517-388-3662

 

I think he's in the Lansing area....or so.

 

 

Thanks very much! I have a call into him. And Jeff @ FAST is not taking on anymore work right now - FYI

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