To Shim or not to Shim?

[Kanoe]

3rz getting it's first valve adjustment. A couple of questions for those who have more experience...

I have a few exhausts that are for sure getting adjusted, a few that I am on the fence about. I have some that are a TIGHT .013 (nearly a .012) which is right in spec. but as we know the exhausts tighten. I was considering going one shim down on these which would make them a TIGHT .015. This is slightly over the spec of .014 but only slightly. Would this matter much? This seems like a good long term plan as I would rather set everything loose (close to .014) while I am in there. Any comments Please?

And secondly, I have seen no change in my intake measurements since my last check 4 years (50,000km) ago. In general, does anyone know which way the intake valves tend to go in the long run? Do they tighten up as the exhausts do?

Thanks All.

 

[Scramble]

Did you upgrade your exhaust manifold? They shouldn't go out of spec when you switch out the cast iron. But yea, if I were you I'd shim since you're already in there. You're right on the fringe. Never heard of the intake valves going out of spec.

 

[Kanoe]

Yes, I switched to the tacoma mini header a couple of years back. My cast one was not cracked at all as it turned out.

Thanks for the reply.

 

[Kanoe]

After sitting with my spreadsheet, I have come to a fork in the road.

1- Buy 5 new shims and set all exhausts at approx. 0.013

2- Buy 8 new shims and set all exhausts at approx. 0.015

I know the .015 is technically out of spec, but I've found a few references saying that it is a good target for the exhausts as they tighten up of their own accord in time.

Comments welcome.

 

[Kanoe]

Anyone who has done this? 3rz Friends??

Going to order the shims today at lunch. They are only available from California so shipping will be a while.

 

[Kanoe]

Ordered

Ordered. Decided on the .013. That should be good for a good long time.

One shim size coming from Toronto, one from Kentucky and one from California. Dealer said they have never ordered them before at all. They also said they have never done a valve adjust on a 4runner or Tacoma. Maybe mine was the oddball having one on the edge of spec. Or maybe not many people bother to check.

 

[gamefreakgc]

After sitting with my spreadsheet, I have come to a fork in the road.

1- Buy 5 new shims and set all exhausts at approx. 0.013

2- Buy 8 new shims and set all exhausts at approx. 0.015

I know the .015 is technically out of spec, but I've found a few references saying that it is a good target for the exhausts as they tighten up of their own accord in time.

Comments welcome.

This was the right call. Toyotas rarely come out of adjustment (except for the 3VZ-E) so better to be in spec then getting lower compression.