In the hole measurement?
- Thread starter BWL
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- Tags hole measurement
I think the BSP has a dished piston in it. I have not pulled the head on my BSP yet but I am pretty sure it is dished. I would put a flat top in. Need to measure because you might not have enough clearance to put a longer rod in. You wont know tell you measure. If you do end up doing a flat top and the billet rod I would look at the UT2 piston and long rod swap.
Okay, that's something I didn't know about. Let me get this straight: I can take the UT2 GX160 piston and run it in the GX200 clone? Of course running a longer rod to compensate, with an ARC extra long rod I can have a lighter connecting rod and piston and more compression and hang time even at the standard length? (compensation accounted for)
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They usually run a +.100 rod with the UT2 and it's a flat top. I think you have to run a thicker head gasket as this usually puts the piston flush with the deck and you need at least .025" between head and piston. I would talk to a tech at the place you buy your parts from. They also sell a +.080 rod they recommend for the 160 but I think it puts the piston at .020 below the deck like stock on a 196. I have not done this yet so I would talk to some of the guys one here that have done this as I have only read about it. I am not talking from experience just from what I have read. I want to try the UT2 out maybe next build my self. If a person is buying a rod already why not right?
Another cool thing you might be interested in later and what might make just getting a +.020 rod with a thicker head gasket worth it is how I am building my motor. I have a 196 block that has an over bore and am running a +.020 rod with a predator piston to make my 196 a 208. The block was $40 and the piston with rings and pin was $15. Still in the middle of building this. Its my first build 
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Depth gauge. Measure parallel to wrist pin then you can push down on the bottom fo the piston to rock it one way and measure at the top. The more piston to wall clearance the more the piston can rock. So you have to consider that and take the highest measurement and add .030 to that for piston to head clearance. For compression calculations use the in the hole measurement taken parallel to the wristpin where rock does not affect it.
Another cool thing you might be interested in later and what might make just getting a +.020 rod with a thicker head gasket worth it is how I am building my motor. I have a 196 block that has an over bore and am running a +.020 rod with a predator piston to make my 196 a 208. The block was $40 and the piston with rings and pin was $15. Still in the middle of building this. Its my first build
or is this meant to help with clearance issues?
thanks,
phil
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Usually the z4m is the piston used for this swap .. I have done the ut1 and also a zh8 which requires the skirt to be cut ..But you need to measure with those pistons if planning on using them .. the z4m is available in different compression heights ..To answer your question Phil a longer rod provides slightly better rod angle and the head gasket is simply for piston to head clearance
There is more than one benefit from going with a flat top in your case BWL .. you are using your motors for torque .. the lighter you can make the rotating assembly the faster it will spin up creating more torque .. but definitely follow ole's direction and make sure you have 30 thousands piston to head clearance ... You may have pushed the jug off your predator for this reason and you don't want to do that again
If you do the Predator piston with an overbore it required a +.020 longer rod because the Predators have a longer stroke than the honda clone so the compression height of the piston is different and the piston will sit deep in the hole. I don't remember the range but NR racing told me the Predator piston will still sit below the deck.
Either way I would measure and try to fit the longest rod you can with what ever set up you do. Every little bit helps. If it was me I would try to get the piston as flat with the block as I could with out going out of the hole and use your gasket to control clearance.
Either way I would measure and try to fit the longest rod you can with what ever set up you do. Every little bit helps. If it was me I would try to get the piston as flat with the block as I could with out going out of the hole and use your gasket to control clearance.