valve to piston

Posted By: Ian

valve to piston - 11/09/09 04:35 PM

going from a solid ft to solid roller would increase v to p clearance with similar cam and create more cranking comp because of ramp speed open and closein the valve true or not

Posted By: Crizila

Re: valve to piston - 11/09/09 05:45 PM

Quote:

going from a solid ft to solid roller would increase v to p clearance with similar cam and create more cranking comp because of ramp speed open and closein the valve true or not

Generally speaking, true. Problem with the question is "similar". They are both apples, but a Macintosh tastes a lot differtent than a delicious - so to speak.

Posted By: Ian

Re: valve to piston - 11/10/09 04:33 PM

anyone measured this before

Posted By: Cab_Burge

Re: valve to piston - 11/10/09 04:46 PM

Ian, I have checked many camshafts for V to P clearance, many of the closest V to P where with solid lifter cams, not with roller lifter cams. There is one way to try and judge the V to P and that is with the lifter hieght( valve opening) at TDC if you can get that information from the cam grinders

Posted By: Bob_Coomer

Re: valve to piston - 11/10/09 04:51 PM

Why would anyone want to switch to a roller with the same spec's?
I would just keep the flat tappet in that case.
Its hard to compare a flat tappet cam to a roller even if the spec's are close..They are totally diff. I always check V-P specs, and degree the cam each and every time one is installed no exceptions period.

But to answer your direct question relatively speaking "Yes".

Posted By: Ian

Re: valve to piston - 11/10/09 05:45 PM

thanks for the reply my flat tappet has 259/265 @050 590 595 on 109 close v 2 p on intake my roller has 267/274 700/ 670 on 108 seeing if the engine needs to come out for fly cutting or not