here is my retarded frankenstein build. how about that piston to deck height lol.


82mm lsvtec
nippon gsr pistons
ls rod with arp bolts
small end of the rod milled down to have play when the pistons were mounted.

so i think according to zeal i have somewhere like 5 thou piston to deck. my machinist says you really want to be at least 38-40 thou, so consequently ive got a .040 cometic in this thing. should put me right around .045 just over the min limit. with itr cams and valvesprings i dont see this motor going above 8400 rpm. do motors really expand the rods etc that much at rpm that i need to be worried? i milled the head down a bit to gain some compression back. this should be right at 10.8:1.


82mm looks pretty thin on the iron part of the sleeve....research says i should be good to go on motor at 82 but im just a bit sketched out

 

Looks pretty typical. Do you have a depth mic to measure the distance? I prefer not to get under .040 but have run tighter on stock parts with no contact. For a street motor its not that big of an issue. For highly strung out road race or endurance motors you need more room for all the stress, stretch, heat and rpm. If you want to borrow pretty much any tool, pm me... I dont think we are that far away from each other.

 

thanks for the offer. im about 40 minutes away down in kingston but head up to albany to hang out with friends up there every few weeks grab some paesans or bombers and pretend im in college still lol

 

I ran my old GSR build @ 82mm and had no issues in 15-20k miles (it was stolen)

82mm GSR block, GSR crank/rods w/ Pr3 pistons, B16 head w/ Skunk tuner 1's. Made peak right at 8100, shifted at 8500 to stay in the power.

 

Piston to deck height means almost nothing.

Piston to HEAD height is one of the most important measurements in a high performance engine.

 

You'll be more then fine with a lower rev like 8400, and the cometic .040 gasket. IF, that does indeed give you .045 P2H clearence.

I've been running .036 P2H on my setup reving to 9200. I do have manley rods, and standard pin Arias pistons so not alot of weight on the end of the rod.

 

Piston to deck height is part of the math required. The numbers he was talking about 0.005 PTD and .040 HG were the piston to head clearance (.045 estimated)

 

yeah thats how it turned out. and at 82mm i had to get a specific 82mm gasket ( i dont think the oem gaskets are that big 81.5mm iirc). if i ran not 82mm then it would protrude into the bore and essentially take the place of the head and leave me with only .005 pth.

this will eventually make its way into my daily driver em1 but im going to put it in my turbo ej1 over the winter while that motor is out for some work and quite frankly so i dont have to listen to that thing slap around like jay z's hand on beyonce's *** when its 8 degrees outside and i have to drive it.