New OEM valves

[Black95TSIawd]

I'm building up my head this winter. BC 272 cams, springs/retainers, and a light port job to clean up and smooth out the casting. My question is what are the stock valves good for? I plan on getting new valves and guides, but maybe for my goals, i dont need stainless or nitrite coated? I'll probably to revving out to 8 - 8.5k when i upgrade the turbo/intake mani in the spring.(dont need to rev that high for now on the 16g) So help me make a decision as all the other parts are already in my garage and i'm just itching to get it all together.

 

[unior]

SS valves are more resilant to burning up

sodium filled valves are great for extended high revs since they transfer heat away from teh head of the valve to the stem where the heat can be taken away by coolant and oil

 

[GVR4592]

There a couple guys that have made over 700whp with stock valves, I think it's overkill to upgrade unless you actually need them.

 

[awdtalontsi1992]

Your valve choice will really only depend on one thing...money! An upgrade to SS valves would be good insurance but also is in no way necessary unless you are going to make some serious power. Why are you replacing them? I would have the machine shop check them out first. If they are in good condition and the stems aren't worn then keep them.

 

[Black95TSIawd]

Your valve choice will really only depend on one thing...money! An upgrade to SS valves would be good insurance but also is in no way necessary unless you are going to make some serious power. Why are you replacing them? I would have the machine shop check them out first. If they are in good condition and the stems aren't worn then keep them.

For some odd reason, i'm pretty much building a brand spanking new head. I just feel rest-assured knowing that everything is done right. The guides might be fine as well as the valves, but are they good for another 20, 30, or 40k? I'd rather know they are new and would not prone to fail or smoke and i probably would not have to replace them again ever unless i plan on building a race only car.(which i'm not)

 

[awdtalontsi1992]

9 out 10 heads I have seen with wear are in the guides only. Most of the valves I have checked...from desiels, imports, v8s, lawnmower engines, etc.....showed little to no wear. The nice thing about reusing the valves is they have been proven to not have flaws from the factory. They should be good for an untold number of miles. Your new guides....which is a good choice to replace....will probably wear out first. But I guess if you have the money....I envy you.....I would definately invest in a set of SS valves instead of OEMs just for extra insurance and durability.

 

[BISHILVR]

Most of the dsm heads I've had apart still have the hone marks in the valve guides. It seems to be the valve stem that wears instead on this engine.

 

[GVR4592]

I've probably rebuilt 50 or 60 4g63 heads this year and not one had excessive wear on the stems, all of the wear was in the guides.

 

[BISHILVR]

I've done that many, and all of mine were stem wear at our machine shop. We have all of the best equipment to measure with as well.

 

[GVR4592]

I've done that many, and all of mine were stem wear at our machine shop. We have all of the best equipment to measure with as well.

What equipment is that?

 

[BISHILVR]

In other words Starrett, Mitotoyo, some of the best measuring tools around, not cheap harbor freight shat. In fact, MOST of the heads that I've ever done (not just dsm) have plenty of life left in the guides. The exception would be old v-8 stuff with subpar materials used in the first place, or old bronze sleeves. I can internal mics, external mics, all day long, and dsm stuff usually comes out great, alot of uneccessary guide replacement takes place in the dsm world because owners dont understand how to properly check for valve to guide wear, and just toss guides in for good measure. If I can figure out a way to get a picture of the inside of a guide I can show you the hone marks in the guides I have sitting here with 100,000 + miles on them, nothing wrong with them at all, they have another 100,000 in them.

 

[GVR4592]

I have cylinder blocks with the hone marks still on them that are .003" out of round, crosshatching is irrellevant. What specificaly are you using the measure the guides?

 

[SlowSpyder]

I have cylinder blocks with the hone marks still on them that are .003" out of round, crosshatching is irrellevant. What specificaly are you using the measure the guides?

maybe with a split ball gauge.

 

[BISHILVR]

What are YOU using to measure YOUR guides? Thats the better question, because chances are you are'nt doing it right. We've had zero problems with all of the guide to stem clearance that I've measured and ok'd. I made the investment in the tools to remove and install valves guides, ream and hone the new guides, cut valve seats, check concentricity, etc. What do YOU own? Dont play games with me on this, I have assembled thousands of valve trains, I work as a tech and have built many a race engine that went on to top 10 seasonal finishes in the motorsport arena. You are free to do what you want my friend, its your money and your problem. I deal with facts, whereas you want to argue that "4+4=9 therefore" and I wont allow that.

 

[GVR4592]

I work for one of the worlds largest engine remanufacturer's, and I am one of the guys that rebuilds the cylinder heads. We generally do 75-80 heads a day. We use the Sunnen gauge set for measuring the guides and we also check the Ra of the guides, most shops aren't even aware that equipment is available. All I'm saying is that we very rarely see a valve stem that is out of spec, and almost every intake guide is beyond repair on the 4g63's.

 

[BISHILVR]

Our findings are different then, thats all.

 

[Black95TSIawd]

There a couple guys that have made over 700whp with stock valves, I think it's overkill to upgrade unless you actually need them.

Reading through this thread, you seem to know exactly and have the experience. New guides and STOCK valves? I'll probably be doing 400 on pump after the turbo upgrade.

 

[bfdahl]

You need to have you head cked, and have the machine shop make a recomendation on what you should do.

when i worked a Satans dealers I had my shop ck all the guides on the heads I sent, and they usually only replaced the guides in heads that had lost a timming belt and the bent valves got stuck in the guides.

I have modest goals (400 whp) Im using stock valves and have no plans on getting anything else. I have a coulpe of extra sets of stock valves and Im using stock retainers with 99$ crower springs.

what ever you can afford I guess.

 

[BISHILVR]

Thats my findings, we only replace them when they are cracked from a belt breaking.

 

[Black95TSIawd]

Well, i'm getting new guides regardless. I might have found a deal on some ferea valves, if not, i'll just stick with new oem valves.

 

[01QuadDak]

What is interesting about the above comments is that many a time, the valve guide is made of a softer material than the valve itself.
I know that some alloys of aluminum are incredibly abrasive to tool bits, and will destroy them quickly, even when machined properly.
Typically a bronze valve guid is there because the inherent softness of the metal should prevent wear on a more expensive part. IE the valve.

 

[BISHILVR]

But then I've had plastic wear through steel many times

 

[Black95TSIawd]

Might as well do it right the first time and i have until march when the season opens so i can elongate this project until funds are made available. Im going with ferrea SS valves with new bronze guides.