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Cal-look/High Performance => Cal-look => Topic started by: nicolas on April 27, 2014, 11:03:29 am



Title: issues with 1.25 rockers and pushrods
Post by: nicolas on April 27, 2014, 11:03:29 am
i have been building my 2007cc type3 engine for a while now and i have to make the conclusion that i need/want to do everything twice…  ::)

one of the last remaining issues are the pushrods and rockers. i am using a FK44 cam but with 1.25 rockers (original VW) with swivel feet and chromoly pushrods. everything works OK, but in order to have the right geometry i have to use thick shims under the rockers (1.5mm) this in order to have the swivel feet not bind on the rockers. so this way i had to cut the pushrods longer than theoretically needed (now 275mm)
so my first question is if there is a way 'around' these shims so everything can line up, but be shorter/ compacter. i was thinking the adjustment of 1.4 rockers is on the other end of the rocker, therefore leaving the least amount of offset on the valve side of the rockers. but are there 1.25s designed this way (scat,…)?
second question is do i need aluminum pushrods? i want to know if it is worth the investment (as they seem to be more expensive then regular CrMo) and is there a realistic and noticeable difference in use in this particular engine? if so or not what strength is needed? wall thickness…?


thank you for reading


Title: Re: issues with 1.25 rockers and pushrods
Post by: fish on April 27, 2014, 12:51:34 pm

There are swipe foot 1.25 rockers on the market namely Scat, Empi, Bugpack and 1.3 from CB, with your amount of lift and RPM I would just go with Manton Chromoly pushrods


Title: Re: issues with 1.25 rockers and pushrods
Post by: brian e on April 29, 2014, 23:23:42 pm
Every time I have used elephant foot or swivel ball adjusters, I have needed to machine/grind at least .060" from the adjuster side (opposite the nut) of the threaded end of the rocker arm.  This will allow you to back the adjuster out further without binding it up.  I have never had to use shims when doing it this way. 

Hope this makes sense.

Brian


Title: Re: issues with 1.25 rockers and pushrods
Post by: nicolas on May 01, 2014, 16:55:15 pm
Every time I have used elephant foot or swivel ball adjusters, I have needed to machine/grind at least .060" from the adjuster side (opposite the nut) of the threaded end of the rocker arm.  This will allow you to back the adjuster out further without binding it up.  I have never had to use shims when doing it this way. 

Hope this makes sense.

Brian

thank you! that makes perfect sense… so much that i feel stupid not to have thought about it myself.  ::) oh well. i may as well go this route as the rockers and shafts are perfect in any other way and i was holding back buying a new part if this is actually just fine.
so i will grind/machine a bit away, clean the treads and see what length i will need. seems there are different strengths of pushrods. i have a set of jay see 3/8 x .058 190,000 psi pushrods. i think they are overkill, but what would be the lightest CrMo pushrod i could use?

thanks




Title: Re: issues with 1.25 rockers and pushrods
Post by: Taylor on May 01, 2014, 18:40:57 pm
Before you machine the rockers, have you checked the geometry?   It would be a waste of time if you end up needing shims to correct geometry anyway.


Title: Re: issues with 1.25 rockers and pushrods
Post by: nicolas on May 02, 2014, 06:12:53 am
Before you machine the rockers, have you checked the geometry?   It would be a waste of time if you end up needing shims to correct geometry anyway.

i will do it more accurate, but i might work out, barely, so i will test fit it and see what is needed. thank you for the input, but no worries this has to be correct otherwise i could not have bothered.

as for the pushrods i am still in the blue…  the set i had was not CrMo, but in a shiny material (more like Stainless steel), was lighter and seemed to have kept up really good.


Title: Re: issues with 1.25 rockers and pushrods
Post by: K-Roc on May 02, 2014, 16:23:43 pm
Before you machine the rockers, have you checked the geometry?   It would be a waste of time if you end up needing shims to correct geometry anyway.

Exactly!  I just finished up a stroker motor with Stock style rockers and swivel feet, required a good stack of shims and the pushrods ended up at 11.300" to get the geometry in the sweet spot.

" It is what it is"


Title: Re: issues with 1.25 rockers and pushrods
Post by: Jim Ratto on May 02, 2014, 20:18:07 pm
Same here. Just redid my 2165 with stock 1600 rockers and 911 swivel foot. Had to pack quite a shim stack under to get screw where I wanted @ 50% lift. No grinding needed.