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Cal-look/High Performance => Pure racing => Topic started by: paul_f on June 18, 2010, 09:47:36 am



Title: Checking coil bind and retainer clearance using adjustable pushrod
Post by: paul_f on June 18, 2010, 09:47:36 am
I am changing my T4 from the stock rockers to Pauter (so 1.3 to 1.48 ratio). The new lift will be about 0.565"

I have a very strong steel adjustable pushrod that can cope with dual springs, so I was thinking that at max lift I could wind the pushrod out and check to see how far I have before I get to either coil bind or the retainer hitting the guide.

Can anybody see any problem with doing it this way (I checked and the pushrod is strong enough)? 

How much clearance should I be using - is 0.100" enough?

Cheers
Paul


Title: Re: Checking coil bind and retainer clearance using adjustable pushrod
Post by: Peter on June 18, 2010, 11:32:25 am
Hey,
I did it your way and no problems!
0.100 is good


Title: Re: Checking coil bind and retainer clearance using adjustable pushrod
Post by: paul_f on June 18, 2010, 15:33:51 pm
Thanks.  I have just checked and unfortunately I only have .070" so I am going to have to rework the heads if I want to use these rockers :(

I'll do it over winter


Title: Re: Checking coil bind and retainer clearance using adjustable pushrod
Post by: Rasser on June 18, 2010, 15:39:25 pm
Or use an original rocker/valveadjuster. Each full turn on the adjuster screw equals 1mm.

This method is also helpfull when checking for valve/piston clearance. Just adjust the screws (negative) for the clearance you want, and turn the engine over to see if you have the wanted clearance.


Title: Re: Checking coil bind and retainer clearance using adjustable pushrod
Post by: paul_f on June 18, 2010, 15:47:05 pm
Or use an original rocker/valveadjuster. Each full turn on the adjuster screw equals 1mm.

I did try to do that before, but I found I coudn't get enough torque on the slotted screw to increase the lift


Title: Re: Checking coil bind and retainer clearance using adjustable pushrod
Post by: Frallan on June 19, 2010, 16:08:48 pm
But be very careful if you are doing this for the first time.
No sparkplugs so you get smooth handcranking and the sligthest resistance, back off.
Very often (almost always) the interference is not flat on to the valve head and if you touch the side of the valve head with any force, you will bend it, even if it so slightly.