372XP High Comp Pop Up 50mm Piston

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mixxer

Lord of Combustion
Joined
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Location
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Glad to see these finally available again..
Screenshot_20190821-220057.png
Stock 50mm bore size.... Pop Up/ raised center dome / higher compression..

Just ordered one to try...

My 372XP is lightly modded including porting and threebond used in place of base gasket for higher compression...

Right now 160 PSI on the nose...

Would like 170~185 PSI for personal tuning preference...

We will see where this one ends up at...
 
Glad to see these finally available again..
View attachment 754727
Stock 50mm bore size.... Pop Up/ raised center dome / higher compression..

Just ordered one to try...

My 372XP is lightly modded including porting and threebond used in place of base gasket for higher compression...

Right now 160 PSI on the nose...

Would like 170~185 PSI for personal tuning preference...

We will see where this one ends up at...
Any updates on how it turned out? I put one in a 2166 a few months ago. The squish at the tip of the solider was .016 so I took another .oo4 off the pop up and it had 190psi compression right after install. That was with oem rings.
 
Mine Ran good, but I’m dealing with an intake leak in the boot right now, here are some pics to satisfy I hope.

Once the intake is fixed I’ll be able to give an accurate performance report
 

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Ran good, but I’m dealing with an intake leak in the boot right now, here are some pics to satisfy I hope.

Once the intake is fixed I’ll be able to give an accurate performance report
I've got another one of those pop ups setting on my shelf just waiting to go in a 2172.
 
Curious if you need to run the base gasket or have they left the overall piston height same as stock? Personally really like these new popup concepts.
On the one I did the squish was .016, same as the oem, and I took another .004 off the piston to get the squish to a more comfortable .020.
 
Curious if you need to run the base gasket or have they left the overall piston height same as stock? Personally really like these new popup concepts.
I am running mine without a base. I ran it for about 30 minutes doing some edging (milling) and so far no issues. I’m glad your here weimidog I would really like to here what you think about the larger pockets on the piston compared to stock.
What do you think?
 
Really don't know so any thought would be pure speculation. It will have different Strato timing but if you do the typical gutting of the intake filter holder and boot, not sure it will matter much from a reliability perspective. Which is larger? Usually the stock piston has the larger slots. The AM cylinders also usually have smaller Strato ports and possible the genesis of this piston is from that setup. But the smaller "slot" means less straight air ( or mix if you gut the Strato out ) is deposited at the transfers. But I really haven't done enough with those to overlay theory onto actual data. And it does depend a bit on what you plan to do with the transfers, if anything. Sounds like a fun project though! I've been taking the X-torqs back to Original edition and accept I'm loosing some potential flexibility relative to mods.
 
Really don't know so any thought would be pure speculation. It will have different Strato timing but if you do the typical gutting of the intake filter holder and boot, not sure it will matter much from a reliability perspective. Which is larger? Usually the stock piston has the larger slots. The AM cylinders also usually have smaller Strato ports and possible the genesis of this piston is from that setup. But the smaller "slot" means less straight air ( or mix if you gut the Strato out ) is deposited at the transfers. But I really haven't done enough with those to overlay theory onto actual data. And it does depend a bit on what you plan to do with the transfers, if anything. Sounds like a fun project though! I've been taking the X-torqs back to Original edition and accept I'm loosing some potential flexibility relative to mods.

Are you asking which one is the larger one in the pic?

The top is the lil red barn
The bottom is stock

Upper pockets are smaller on the lil red and the lower pockets on the piston are larger than stock. Smoother than stock too

I’m not going to pretend that I know exactly how strato works with this cylinder arrangement, let alone any cylinder arrangement. I actually don’t understand the purpose of the upper pockets on the piston, they don’t seem to go anywhere..
 
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