hey what is the volume of the sohc head? and i got hr 259 cams the guy at venolia pistons whats to no thge center line of that cam can some one help me. also the pistons i got i can get gas ports around the top of the piston that when the piston compresses it pushes on the rings for better seal. its 17 dollors more a piston. is it worth it? should i do the gas ports? it sounds like it will help alot. some one please anser me if you can. here is a picture with the gas ports . hep a brother out guys talk to me people!!!!!!!!!!!!!


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ny one going to help? i thought this forum is for help with questions on ower cars. no one want s to help a brotha out??????

 

Sounds odd to me... why not just get total seal rings and call it a day... I wouldent trust those "ports"

 

putting holes in the piston doesnt sound like a good idea to me. butive never seen that stuffon any engine ive worked on so i couldnt give you a good answer as to if it helpshold compression.

no idea what volume SOHC head combustin chamber is. but im sure if youkeep searcihngthe net youll find it or find the procedure on how to find it.

i second the motion on the total seal rings tho.

 

total seal pistons are acually so tight that you have to disable your pvc system due to the exesive clyinder pressure... they provide 0-1% pressure loss on a leak down test... and if those pistions need special 17 dollar holes to do the same thing... I just think it would weaken the piston around the "port" and since your running nos it would melt threw that thinner metal above the port and go boom faster if you happen to run into a lean condtion... where if you had normal pistions I think they would withstand the lean condition for a wee longer...

 

my dads racing s&s motorcycle uses venolia pistons exclusivly. my dad has the ports on his pistons and his bike is 14: 1 ratio. the guy said they use those holes on top fuel dragsters and actualy work very well. he said with the holes it works grat with the nitrous going. i dont see them causing problems i see more gains with that then anything else. venolia uses total seal rings in everything they use. he said it would seal even more with the ports. it also was said to help from the top ring from microwelding to the piston.

Im geting total seals any way. just thought you could never have anuff sealing power for the piston.

and any one no the center line of the hr 259 cam?? or got full specs i need to no the overlap so the pistons get made to the specs

I think im guna get the ports. ill be the first to do it. i think kuz the pistons are geting custom made for nitrous and boost they will make the ports realy strong