Kurtomac

iTrader: (5)

Using YT rockers supplied shims TFS heads...i attached a couple of extra pics kind of side shots of the valve train...doesnt look like the rockers arent pushing down the valves very much, first time Ive used other than stock rockers...just back in the day seemed like they would push down a good bit...Im using new lifters....surely theyre not bleeding down that fast (brand new 850-16 comp oe replacement lifters)? Prob just an illusion since its my first time with YT rockers
Anyways heres the setup TFS 215s milled .020, YT rockers, 7.5 Pushrods, MLS gaskets, supplied YT shims....didnt check PR length, just used what VR recommended, valvetrain isnt that loud so Im assuming 7.5s was the right one to use
your guys thoughts?

Kurtomac

iTrader: (5)

how much should the springs be compressed? just the lift of the cam...or the lift*1.7 for the rockers?

2000_SS

iTrader: (24)

springs should compress the lift for the 1.7 ratio, since the top of the spring is the roughly the same as the top of the valve.

did you try installing the rockers without the shims?

Jeff@TotalPerformanceEng

iTrader: (6)

Your pictures suck..

Pics with the rockers in place serves no purpose.

Proper length pushrods is NOT just about noise. Its about valvetrain stability.

Get a set of checker springs. Their about 3 bucks for the pair (Comp Cams PN 4758-2). Then get a comp cams PR length checker. Also get some rocker shims (you can get them from mcmaster carr.com) Dial in your wipe pattern perfectly.

After thats all done, THEN check for proper pushrod length. That is the very LAST thing you do.

But having stock TFS 7.5 PR's, YT shims (which I think are somewhere around .040), and .020 milled heads, you dont have the slightest clue as to where your preload is at.

VR mentioned 7.5's because they come free with a set of TFS heads. I'd be willing to bet they wouldnt reccomend that size if they knew you were running shims AND milled heads. At least I hope they wouldnt..

I'd put money on the fact that your preload is too loose.

Jeff@TotalPerformanceEng

iTrader: (6)

First you need to find out what the installed height of the spring needs to be in order to obtain the springs reccomended spring seat pressure.
If you've got a spring with a reccomended installed height of 1.770, but a valve heaght a 1.800, you need to run a .030 spring shim.

You also want to try to run a spring right around .050 from coil bind.

vettenuts

iTrader: (4)

How are you measuring? I thought you had it running?


If you have hydraulic lifters and the TFS valve springs while turning the motor by hand, it will be inaccurate. Use check springs and best to use a dial indicator to check wipe. You are likely compressing the plunger in the lifter while rotating the motor and that is why the lift appears so low.

Step 1 should be to install check springs and check wipe with a dial indicator so any lifter plunger travel is left out.

Step 2 should be measuring for pushrod length using an adjustable pushrod, once the correct shims are installed as determined by step 1.

Don't follow the the YT instructions or LS1Howto, the YT instructions are very confusing and mis-leading. LS1Howto is wrong.

Kurtomac

iTrader: (5)

It is running....i just ran if for a few days...changed the oil and pulled the valve cover to check and make sure everything was still tight.....pulled one set of rockers off to look at wipe...Personally I think the wipe looks fine....now pushrods...I have a Comp Adjustable didnt end up checking and since VR threw quite a few of these combos together using 7.500's I just put it together...They knew the heads were milled and recommended using supplied shims...I ordered and had them milled through them...TEA did the milling and set up the .650 lift springs to correct installed height
Sorry for the crappy pics jeff@TPE...Iphone pics
If you guys agree with my wipe looking fine...Im just going to pull a set of rockers again and throw the adjustable in there (btw do i just bump the motor over until it looks like both valve are totally closed?) and then check for PR length with the adjustable...finding zero last and adding .075 to it for my preload?
Now if it comes out i need 7.525's should i bother ordering a .025 longer PR or just using the 7.5

vettenuts

iTrader: (4)

If the marks on the left photo show your running wipe pattern, I would say it looks pretty good.

Kurtomac

iTrader: (5)

yup running wipe pattern ....next weekend I'll pull valve covers remove a set of rockers and check PR length...is there a way to tell that both valves are closed other than visually watching them close?

vettenuts

iTrader: (4)

Watch for the intake valve to close then bring piston to top. Look in with a flashlight or use a straw to feel for it through the spark plug hole.

Also, a larger diameter pushrod would be helpful if it will fit. Manton makes 11/32 and several make 3/8. Manton is made to your length (custom).

Kurtomac

iTrader: (5)

cool so wait until i see the intake look all the way closed then wait for the exhaust to do the same then check PR length...if i half understand this cam thing...since my cam is a 236 238 should the valves be closed for approx 120 degree turn of the cam....so 60 degrees turn of the crank...1 turn of the crank is 2 turns of the cam correct?

vettenuts

iTrader: (4)

As you turn the motor, the intake will close and then the next time the piston comes up is the compression stroke. When the piston is at the top both valves are on the base circle and you can do your check. Don't need to watch exhaust if you do it this way.