Tech

Even though the entire package (including springs and valves) came from TFS which specified an install height of 1.800"?

Petraszewsky

The installed height for the springs is what they are rated for at that height. Stock LS stuff is 1.800”. What’s the lift on your cam?

For example: Mine is .622 lift intake and .616 exhaust and springs are
Installed Height : 1.800”
Closed pressure @ 1.8” = 180
Open Pressure @ 1.1” = 480
Max spring lift = .700”
Coil bind = 1.055”
Spring rate = 425

To bump seat pressure and get closer to coil bind I installed mine at 1.740”

1.740” installed height - .622 intake valve lift = 1.118”

1.118” - 1.055” coil bind = .063” from coil bind ....

.040”-.060” from coil bind is good to shoot for....you don’t want to be something like .100”+ from coil bind as a example.

Petraszewsky

Just saw your cam specs

So 1.800” installed height - .610” intake lift = 1.190”

1.190” - 1.1 coil bind of your springs = .090” from coil bind

If you use a .030” shim then it should put you at .060” from coil bind but you’ll have to measure each valve/seat/retainer in each of their spots to be sure that’s what they’re coming out to. Also be sure your seat and shim are sitting flush in seat area. For example my heads had a beveled edge in the seat area that wasn’t allowing the shim to sit flush/square. Just label each head and each valve so you know to put the same setup back on each spot. Valve seat depths and stuff can vary and so can stem lengths and retainers which can stack up to large differences. Don’t worry about being a few thousandths variance but tenths would alarm me.

Petraszewsky

I looked up the part number for your springs and it shows coil bind height of 1.080” not 1.100”. So 1.800” - .610 = 1.190”

1.190” - 1.080 = .110”

So a .030” shim would actually set you at .080” and not .060” from coil bind.

The springs state they are good for .650 max lift which leaves them .070” from coil bind if .650 lift was actually used. You only have .610 lift so you could actually stack a .015” and .030” shim to get you a 1.755” installed height and be .065” from coil bind.

Tech

I appreciate your input. TFS has conflicting information on the coil bind height. I got my number from here: https://static.trickflow.com/global/...s-16521-16.pdf but the product page does say 1.080. I'll contact them for verification.

A few of my springs are more than 1.830". Is it a rule of thumb to shim them as close to coil bind with whatever safety margin you're comfortable with? No matter what force the springs exert? The heads come with two different springs. These are the stronger springs, so I'm a little surprised that I need to shim them for maximum force. What's the point of even offering the lighter springs if I need to shim the stronger springs?

1.836" (tallest install height) - 0.060" (safety margin) - 1.100" (picked bigger number until I can verify) - 0.610" (cam lift) = 0.066" worth of shims. If coil bind ends up being 1.080", I'll need to order some more shims.

Petraszewsky

Are you measuring the spring height or the installed height of the valve stem in the head with seat and retainer installed? Sounds like you’re measuring spring free height which is irrelevant for this.

Tech

I'm measuring installed height with a valve spring micrometer with the valves installed in the heads with the retainers/locks.

I just called TFS. They are going to get back to me on the different advertised coil bind values. They also said to install them at the advertised install height of 1.800". Any more force is just unnecessary pressure.

Petraszewsky

It’s not necessarily a rule of thumb to automatically shim as close as you can to coil bind. You’re valvetrain dictates it. You have a pretty heavy intake valve and boost trying to keep it pushed open. Shimming up a little bumps your seat pressure a little to help keep it closed and not bounce off the seat. Shimming helps you fine tune your setup. Just like getting retainers that add installed height help you fine tune to your particular setup is all. No one size fits all. Just my opinion on setting it up. Million ways to skin a cat. Talk with PAC or TFS or your cam company about the specs of your cam and springs and valves and boost and get their recommendation on what would be best.

Petraszewsky

Gotcha....good deal then. If they say that then just shim them as close to 1.800” installed height as you can get.

Petraszewsky

I apologize I got myself confused when you said your springs were 1.830” and talking about using shims. I made me think you measuring the springs with shims under them and not the installed height in the head. Haha my bad

Tech

No worries. You did make me second guess my measurement though, so I just re-measured.

Tech

Uh.. the image uploader appears to be trying to do me a favor by rotating my images. That is _not _ upside down when I view the image locally.

Petraszewsky

Haha can never hurt to measure more than once. And more importantly having fun tinkering around....

scottg

I love this stuff. Wish I knew all the tech talk, But learning, Thanks to you guys.

Tech

Most of the springs took a 0.030" shim to get them to 1.800" +/- 0.005". I ran into the same situation as @Petra, where a shim wasn't laying flat which caused unexpected measurements. I bought 1.500" diameter shims but the pocket seemed like it was a hair under 1.500".

I never measured the install height when I bought them new and was surprised to find rather random shims under the locators. I had my heads disassembled and resurfaced during this project, so I'm curious of the machinist didn't keep track of the shims properly.

Tech

The heads are ready to go except for a final cleaning. I put the engine on the stand today and installed the windage tray and slid in the camshaft. I'm using the Comp LS degree kit and I'm not real crazy about it.

The crank socket (last picture) doesn't seem to jive with an aftermarket keyed long snout crank. When I try to tighten the set screw, the crank socket does not stay flush and causes the degree wheel not to be parallel to the block.

Tech

I was able to make due with the crappy crank socket and came up with 116* ICL. Cam card says 115*. Good enough for me.

Front and rear covers went on easy thanks to Sac City's AlignIt tools. I was surprised to find I could install the rear cover with the AlignIt tool with the engine on the stand. Couldn't get a torque wrench on one rear cover bolt, so I'll make a note to tighten that before the flywheel and clutch go on. Oil pan is also on.

I got one head bolted on to measure for pushrods. I was able to measure one pushrod but ran short on time for the rest.

chpmnsws6

I had a customer pull the threads on his rocker arms with TF heads. Pushrod length was checked on initial build and again after it pulled the threads by the machine shop. I guess its a fairly common problem?

BTR sent these to put in the heads:
https://www.briantooleyracing.com/in...le-repair.html

Just trying to save you a potential headache. Truck made 4 digits on lower boost a few weeks after this.

Tech

Tech

Pushrods are a hair under 7.600". I've read Johnson 2110 lifters should have 0.035" to 0.050" preload. I have a set of 7.650" pushrods from my last engine. I'm debating trying those first since it's not that big of a deal to swap them out later. Thoughts?