AustinONeal Posted July 7, 2006 Report Posted July 7, 2006 i got 160 165 PSI of compression does that sound right for a 420 4 mill trinity? Quote
RILS Posted July 7, 2006 Report Posted July 7, 2006 Sounds pretty low with 17s unless your pretty high in elevation. Quote
AustinONeal Posted July 7, 2006 Author Report Posted July 7, 2006 whats your elevation? 1200 how can i tell if its a 4 mill Quote
RILS Posted July 7, 2006 Report Posted July 7, 2006 (edited) 1200 how can i tell if its a 4 mill Well I think if its a 4mill and you have cut domes and not the spacer plate,you can take the head off and th piston should come a little above the deck "2mm". Stroking can play a # on compression and domes I just spoke to david noss about this today.Im building a 4mill stroker and I dont want to raise my compression any higher than it is its 183psi with my stk stroke now with 18cc domes.He says it with proably go up with the stroker and i want to be around 175psi he recommended 20cc cut domes im at 900ft.Your porting can effect your compression also.Is the motor fresh?Did you get trinity to build it for you or did you assemble it?There are a lot of things that can play in compression especilly when you are dealing with a stroker and costom domes. Edited July 7, 2006 by RILS Quote
AustinONeal Posted July 7, 2006 Author Report Posted July 7, 2006 Well I think if its a 4mill and you have cut domes and not the spacer plate,you can take the head off and th piston should come a little above the deck "2mm". so the piston ill stick up past my head 2 mm what kind of compression should it run if its a fresh a 4 mill trinity Quote
RILS Posted July 7, 2006 Report Posted July 7, 2006 so the piston ill stick up past my head 2 mm If your not running a spacer plate then yes it should. Quote
AustinONeal Posted July 7, 2006 Author Report Posted July 7, 2006 can u see this spacer plat or is it internal like under the head , or is it in plain sight?? so if there is no spacer plate then no 4 mill, but answer question number 1 Quote
decon Posted July 7, 2006 Report Posted July 7, 2006 can u see this spacer plat or is it internal like under the head , or is it in plain sight?? so if there is no spacer plate then no 4 mill, but answer question number 1 the spacer plate goes between the cylinders and the cases...did you buy the quad with the engine or you had it built? Quote
AustinONeal Posted July 7, 2006 Author Report Posted July 7, 2006 the spacer plate goes between the cylinders and the cases...did you buy the quad with the engine or you had it built? came with it can u tell? Quote
RILS Posted July 7, 2006 Report Posted July 7, 2006 can u see this spacer plat or is it internal like under the head , or is it in plain sight?? so if there is no spacer plate then no 4 mill, but answer question number 1 You can have a 4mill without the spacer.Your domes would have to be cut for the extra stroke.If you dont have a spacer and you take the head off then your pistons will rise 2mm above the top of the cylinder deck.If you have a spacer it will be under your cylinders and will raise them 2mm which would bring them back up and you could run stk head or domes.Most builders have the domes cut and dont use a spacer plate,but there are some tthat use the spacer for some aplications. Im not sure how trinity sets them up. Quote
decon Posted July 7, 2006 Report Posted July 7, 2006 came with it can u tell? lol yeah i could tell because you were asking how to tell wether or not you had a 4mill...but that compression seems pretty low for 17cc domes at 1200 feet... Quote
AustinONeal Posted July 7, 2006 Author Report Posted July 7, 2006 so the spacer is pretty small 2 mm huh woulnt that make it a 2 mill?? sorry about all the questions im new to banshee anatomy im a 4 stroke guy but i need to know becuase i got a shee now.. im gong to run out to my shop and look at it really close and ill take a quick picture and post it Quote
RILS Posted July 7, 2006 Report Posted July 7, 2006 came with it can u tell? I assume your running a cool head do you know they are 17cc or is this just what you were told?That seems really low compression for 17s especily with a stroker but they could be custom domes that were cut to spec and they may have just started with a 17cc.The spacer plate will be between your cases and cylinder and will look like a extra thick metal gasket,you should be able to see it.You can pull the head off and look at the domes the cc will be marked on the edge of the dome,and you could check for the extra stroke by bringing the piston to the top of the cylinder.If it doesent come above the top just a little bit 2mm is mot very much then i would take the cylinders off and look for a spacer. Quote
AustinONeal Posted July 7, 2006 Author Report Posted July 7, 2006 send me your email addressed an ill attach pics Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.