1G Who has done valve springs without shop measurements?

[enriquez2000]

Cirious if there are many of us that have just put in springs while on the car without checking measurements.

Jafro showed perfectly why we need to do this but so many videos just show slapping new springs on a head.

Whats your take amd experiences? Mine has to go to a shop either way

 

[97egl]

I've done it several times when running stock cams/valves. Only one time did I run into an issue with a head that must have had work done in the past. When I put the lifters in the intake valves would leak on #3 cylinder. Had to pull it back off and checked installed height which was too high so the valve seats must have been cut down quite a bit in the past on that one. Anything that is going to be running higher lift cams I always check everything but for circle track stuff I just lap the valves in and run it. No issues except that one time. Hydraulic lifters take up some slack, still not the right way to do it since valve train geometry is off and probably causing extra stress on the guides but when trying to put together a head for a race the next day sometimes there isn't time to do it 100%

If you are replacing valves from a stock head which has had no work and lapping them in instead of cutting the seats there really shouldn't be an issue. Lapping gives you a lot longer valve seat life than cutting since not a lot of material comes off. Some instances do require cutting the seats depending on how bad off the are. If I had time I would always measure installed height just to be sure. Other disadvantage besides bad geometry is that your spring seat pressure will be lower with the valve too high and if you don't measure you won't know to shim the spring.

 

[1990TSIAWDTALON]

Spring installed height and coil bind (from BIG cam lift) are the measurements that I pay a lot of attention to. I let my machinist do my last head (and now he is out of business so that SUCKS) after I bent all 16 valves.
I wanted HIM to look at the guides, check for cracks and make sure my head was top notch again and it seems to be (that better not be a jinx). He had all of the shims (if needed, and they weren't) and did head work every day, so it was like the back of his hand.

 

[enriquez2000]

Talked to my machinist and he said they will check for binding pressure bit with stock cams i "should" be ok

 

[1990TSIAWDTALON]

Oh with stock cams you will be fine. Only 12mm or bigger lift would I be worried. So, secretly, you are building this aluminum rod, 11k RPM engine with 13mm lift cams and you don't want to tell us, RIGHT???

 

[enriquez2000]

Oh with stock cams you will be fine. Only 12mm or bigger lift would I be worried. So, secretly, you are building this aluminum rod, 11k RPM engine with 13mm lift cams and you don't want to tell us, RIGHT???

You never know......

 

[danl]

I know one of the proper ways to check valve train geometry on a 4g engine is with a solid lifter. Does anyone know if it is possible to spin the oil pump with a drill while turning over the cams with a wrench to get the lifters to pump up would work as well? Obviousley you would put the pistons at all the same height so you don't go crashing valves. This would also serve to check piston to valve clearance with a borescope once you get the motor back in time.

 

[slugsgomoo]

Even if that could work, I bet it would be a horrible mess. That said, you can't spin the oil pump at RPM while turning the motor and measuring things because you need the timing belt on...

I'd recommend watching Jafromobile's videos about degreeing as there's a lot of helpful information there.

Now that some of the vendors sell pairs of solid lifters (instead of having to buy a set of 16 and finding 7 other people who want a set) it's not unreasonable to do.