Those running a 3.625 stoker with 6.350 rods, what pistons are you using?

[2QUIK6]

I'm finding it to be difficult to find a piston for this combo. The JE 131556 is not the correct piston for the long rods. Wiseco PT109A2 is, but is disco'd, the 5109A2 I think is the single piston part# I think, has the right compression height. Can't seem to find another dish piston that is similar to the stock full dish.
What are you using and where did you get them? I'm hearing that CP's are preferred but I sure can't seem to find them.
Thanks

 

[forcefed3.8's]

A friend of mine has a set of the wisecos. He was going to do a 109 build, then went to a 016 stage 2. If you are interested, i can get you a price.

 

[2QUIK6]

Are they the 5109A2/PT109A2 I think those are the same piston, single vs set of 6 ? New right?
Send me a price if so, thx.

 

[forcefed3.8's]

It is the full set, they are .030 over. PT109A3. Complete with rings, and I think he got the upgraded pins too. I will get more info from him today.​

 

[forcefed3.8's]

$350 for the pistons.

 

[fastblackracing]

I'm finding it to be difficult to find a piston for this combo. The JE 131556 is not the correct piston for the long rods. Wiseco PT109A2 is, but is disco'd, the 5109A2 I think is the single piston part# I think, has the right compression height. Can't seem to find another dish piston that is similar to the stock full dish.
What are you using and where did you get them? I'm hearing that CP's are preferred but I sure can't seem to find them.
Thanks

I am currently designing the pistons for a build that i will be doing soon.

Same crank and rods that you have, I will have them drawn up and ordered by the end
of the week. If you would like I can send you the document with the info when I am done.

I always end up ordering the pistons myself its not a big deal they are good to deal with.
If The ones from forcefed 3.8 do not work out let me know.

 

[2QUIK6]

It is the full set, they are .030 over. PT109A3. Complete with rings, and I think he got the upgraded pins too. I will get more info from him today.​

I need just .02 over Otherwise thats a great deal. Thanks fastblack, send them over if you don't mind. I think we are fairly certain that the Wiseco PT109A2 are the ones that match up to the rod length and the crank used with the right comp height. My builder has probably built a hundred of these motors, either way we will find something or have it made. Looking for roughly 9.0-9.1 comp when done.

 

[David Husek]

I'm finding it to be difficult to find a piston for this combo. The JE 131556 is not the correct piston for the long rods. Wiseco PT109A2 is, but is disco'd, the 5109A2 I think is the single piston part# I think, has the right compression height. Can't seem to find another dish piston that is similar to the stock full dish.
What are you using and where did you get them? I'm hearing that CP's are preferred but I sure can't seem to find them.
Thanks

Wiseco discontinued all there pro tru pistons for our application. The PT109A2 would be the correct piston kit. I haven't found another shelf item for this application. I am working to get my custom piston design into a shelf part for this setup as I only offer 3.625" stoke crank kits with the 6.350" Molnar rods. Contact me for more info.

 

[Ttype6]

I need just .02 over Otherwise thats a great deal. Thanks fastblack, send them over if you don't mind. I think we are fairly certain that the Wiseco PT109A2 are the ones that match up to the rod length and the crank used with the right comp height. My builder has probably built a hundred of these motors, either way we will find something or have it made. Looking for roughly 9.0-9.1 comp when done.

These pistons are correct for your application,however you'll need to use .027" thick Cometic head gaskets to produce 9/1 compression ratio. You will also need to remove some material from the decks to get to 9/1,which is also necessary to get the straight smooth surface required to get a good seal with the Cometics. This is,of course,assuming that your combustion chambers aren't larger than 46cc.

If you choose to machine the block and use the thinner gaskets to accomplish your goal of 9/1,you'll need to machine the intake to line the ports up. Then you'll have an intake that won't work with the thicker gaskets. The first thing you need to know is your deck height and combustion chamber volume,then order a custom set of pistons that will get you to where you want to be without using thinner head gaskets and cutting your intake manifold.

 

[2QUIK6]

Called up Wiseco and they will still make the PT109A2 on custom order only..so I order up a set with the upgraded wrist pins and moly/nitride rings came in at $144 a cylinder, about the same price as the Diamonds off the shelf price, so I would prefer the full dish with these.

 

[GBGN1]

Great, I've got the wiseco's also. No issues but why did they stop making them?

 

[2QUIK6]

Great, I've got the wiseco's also. No issues but why did they stop making them?

The guy I ordered from did not know why they stopped making them, but he was very familar with our cars and used to have one.

 

[earlbrown]

I'm finding it to be difficult to find a piston for this combo. The JE 131556 is not the correct piston for the long rods. Wiseco PT109A2 is, but is disco'd, the 5109A2 I think is the single piston part# I think, has the right compression height. Can't seem to find another dish piston that is similar to the stock full dish.
What are you using and where did you get them? I'm hearing that CP's are preferred but I sure can't seem to find them.
Thanks

Easy peasy. My forged pistons have been done for a while now. Do your math based around a 22cc inverted dome and pick out whatever compression height you'd like to get the compression/quench where you want it.

I've been trying to get a temporary introductory discount from my piston guys. I should have the pricing finalized on Monday.

 

[BEATAV8]

What's wrong with good old diamond pistons?

 

[2QUIK6]

What's wrong with good old diamond pistons?

I just prefer the full dish like the originals rather than the heart shaped dish, that sharp edge looks like it could be a hot spot for detonation. There has been some discussion about that, but there are plenty of folks running them without issue, so its just my preference.

 

[BEATAV8]

Ahh I see. Thanks!

 

[earlbrown]

The main thing I don't like about the diamonds is the unnecessary valve relief pockets. Outside of what it does with the frame front or creating hotspots or carbon deposits, It gets VERY thin at the edge of the piston crown.

 

[Ttype6]

The guy I ordered from did not know why they stopped making them, but he was very familar with our cars and used to have one.

Are you having them produce exact duplicates of the PT1092A?

 

[2QUIK6]

Are you having them produce exact duplicates of the PT1092A?

Yes.

 

[GNBRETT]

Don Cruz uses Diamond pistons on some of his builds. id say if their good enough for him their good enough for anyone.

I just prefer the full dish like the originals rather than the heart shaped dish, that sharp edge looks like it could be a hot spot for detonation. There has been some discussion about that, but there are plenty of folks running them without issue, so its just my preference.