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Discussion Starter #1 (Edited)
Sorry for the dramatic title. I need views on this, as it's very important.

I've been in the process of rebuilding my engine. Some of you may have seen my "Valvetrain Help" thread. ( https://forums.vintage-mustang.com/vintage-mustang-forum/1159758-289-valvetrain-help.html ). I mentioned that my machinist had put Chevy valves into my heads, and everybody quickly said this was bad.

My machinist has been in business for 40+ years and has a great reputation. He was kind enough to let me rebuild the bottom end with him, because we wanted it done properly but I also wanted to be there. He is extremely knowledgeable and competent, and has forgotten more about engines than I'll probably ever know.

I have attached my build sheet/invoice for the machine shop and I would GREATLY appreciate if you could tell me what's wrong with the combination of parts I'm running. I don't want to ruin my engine. I trust my machinist, and he said that he has used this build for many small block Fords and they turned out great.

Thanks in advance...

Engine Build Invoice.jpg
 

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Discussion Starter #2
Should also mention: I got a new cam, lifters, and pushrods as well. I assume they're tailored to match the build. He put new studs in the head for adjusting the valvetrain. I reused the rocker arms and nuts.
 

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Discussion Starter #3 (Edited)

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If you truly trust your machinist, why are you shopping for opinions now? It seems that your due diligence about your machinist and the scope of your build should have been completed before you hired him to build your engine. Am I missing something here? (I did not read the earlier thread).
 

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Discussion Starter #5
If you truly trust your machinist, why are you shopping for opinions now? It seems that your due diligence about your machinist and the scope of your build should have been completed before you hired him to build your engine. Am I missing something here? (I did not read the earlier thread).
I do trust my machinist, and had no intentions of changing what he had put together. I did some quick research about the parts he had suggested and saw no issues or problems. However, three people all seemed to agree that Chevy valves in a Ford head could be problematic. I wanted to get more opinions before I fire it up and potentially ruin my engine... and I don't think that's a bad thing.
 

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I do trust my machinist, and had no intentions of changing what he had put together. I did some quick research about the parts he had suggested and saw no issues or problems. However, three people all seemed to agree that Chevy valves in a Ford head could be problematic. I wanted to get more opinions before I fire it up and potentially ruin my engine... and I don't think that's a bad thing.
As long as two of those people are not you and your machinist, build on. Everyone has an opinion. Only YOU have the engine.
 

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Discussion Starter #7
As long as two of those people are not you and your machinist, build on. Everyone has an opinion. Only YOU have the engine.
I'm well aware of this and agree completely. However, to completely ignore input saying that the combination of parts I have could cause problems in my engine would be foolish and potentially very expensive. I'm not looking for advice on a new build, I'm looking to verify that what I have won't be a problem.
 

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If you are truly worried about the Chevy Valves, then before you bolt the heads down use clay or silly puddy to convince yourself that there is enough clearance between the pistons and valves. Turn the engine over slowly with the heads bolted down and stop if you feel interference. THat is the only thing I can think of that would toast the motor instantly.
 

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Ok, well, the other day someone on VMF (the facebook group version) told me that control arms should not be greased because grease degrades rubber bushings.

The point is that I would trust someone who has 40 years of experience who you know knows what they're doing, over some rando on the internet with unknown background. Most people here on the forum are very sharp. But there are always a number of people who speak with authority but have no data to back it up.
 

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Discussion Starter #11
If you are truly worried about the Chevy Valves, then before you bolt the heads down use clay or silly puddy to convince yourself that there is enough clearance between the pistons and valves. Turn the engine over slowly with the heads bolted down and stop if you feel interference. THat is the only thing I can think of that would toast the motor instantly.
I already have the heads and intake bolted on. I can turn the engine over, and I don't feel anything contacting... but it is a little difficult now that there's a little bit of compression.

Alex, I clarified on your valve train thread. My comment was pure sarcasm...

Allen
Okay, thank goodness. That's what I was hoping. Hard to tell tone over the internet!
 

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No need for drama. :) It’s can be a bit of a challenge if the person assembling is different than the person machining. That’s why you should be checking everything. The first time is fun. The second? Not so much.

Inherently parts is parts. If the machine shop did his job, the valve seats in the heads have been modified to fit the Chevy valve sizes. No biggie. As mentioned, no real reason to do it these days, as there are a lot of other options, but whatever as the kids say. Chalk it up to old-school thinking.

Also, as mentioned, you’ll need to pay close attention to the rocker arm geometry and push rod length during the mock up part of the build. But you should be doing that anyway.

If the shop has done this in the past, they should give you an idea of which pushrods you’ll need. But, you still have to check.

Get back to work! :)
 

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Discussion Starter #13
Ok, well, the other day someone on VMF (the facebook group version) told me that control arms should not be greased because grease degrades rubber bushings.

The point is that I would trust someone who has 40 years of experience who you know knows what they're doing, over some rando on the internet with unknown background. Most people here on the forum are very sharp. But there are always a number of people who speak with authority but have no data to back it up.
I'm aware that the internet gives a voice to those who might not necessarily deserve one, but I was just a little concerned because the people who thought it was problematic were knowledgable and long-time members.

No need for drama. :) It’s can be a bit of a challenge if the person assembling is different than the person machining. That’s why you should be checking everything. The first time is fun. The second? Not so much.

Inherently parts is parts. If the machine shop did his job, the valve seats in the heads have been modified to fit the Chevy valve sizes. No biggie. As mentioned, no real reason to do it these days, as there are a lot of other options, but whatever as the kids say. Chalk it up to old-school thinking.

Also, as mentioned, you’ll need to pay close attention to the rocker arm geometry and push rod length during the mock up part of the build. But you should be doing that anyway.

If the shop has done this in the past, they should give you an idea of which pushrods you’ll need. But, you still have to check.

Get back to work! :)
What exactly should I be looking for regarding rocker arm geometry and pushrod length? I am definitely trying to avoid a second time around :grin2:
 

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I'm well aware of this and agree completely. However, to completely ignore input saying that the combination of parts I have could cause problems in my engine would be foolish and potentially very expensive. I'm not looking for advice on a new build, I'm looking to verify that what I have won't be a problem.
Why would you take the opinion of SGOTI over your machinist who's done this before? I'd listen to someone who could tell me, "Hey, I did this same thing, and here's the problem I encountered". But the guy who just says, "Oh, no, that won't work" without anything to back it up... not so much.

It's interesting, though, that the topic came up. I was just reading -- literally yesterday afternoon -- an article on Ford smallblock heads. The author says that using larger Chevy valves was a common practice. According to the article, the only potential issue was that cutting the seat larger would get you out of the induction hardened area of the head, leaving non-hardened cast iron. Not a problem (according to him) for a street engine. Ah, here's the link: Modifying Small Block Ford Cylinder Heads

Now, is this guy more credible than someone else? I have no idea, but a quick Google search will bring up quite a number of references detailing pretty much the exact same thing.
 

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Valves just go up & down, so as long as the dimensions are right and they seal in the heads, why would the fact that they were used on a chevy motor too matter?

I had a 354 Chrysler Industrial Hemi rebuilt by a local shop (in business forever with a good reputation) and the valves use on that were the same size as some ford big block motor, so that's what he used during the rebuild. They were dimensionally the same.
 

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If the size of the valves you posted 1.84I/1.5E is what’s installed, you will be just fine. You actually could have gone slightly larger in the intakes. When you mentioned Chevy valves did you disclose the sizes? If not, everyone probably assumed 2.02/1.94.

You will want to make sure to do some port work on the exhaust side of the heads to take advantage of the larger valves. Make sure the intake sides are just cleaned up.
 

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Guys, did anybody look at the other thread? It wasn't the size of the valves LSG commented on, it was the length. Chevy valves are shorter in length than Ford valves potentially causing rocker arm geometry issues. The pushrods will potentially be too long now and the contact pattern between the rocker arms and the stems of the valves may be less than optimal.

The OP needs to verify his geometry and make adjustments as necessary to ensure a good contact pattern on the valvestem. If he does that he'll be fine. If not then wear issues may show up down the road from side loading the valves. The problem comes when guys just slap it all back together without checking and then wonder why the valves and guides prematurely wore out on the heads they paid good money to completely reccondition.

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I just went back to look at the other thread again and saw the new info that was added this morning. LSG pretty well gave the OP all the info he needs. Now it's time to start checking geometry to see if those new pushrods are the correct length.

Alex, I also want to point out that you never responded about if you have rail type rockers. You don't want to use those with shorter valves as the rails can contact and wear on the locks and retainers.

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I think those valve sizes are pretty good for a SBF head, really. 2.02's (and anything larger, though I don't know how you'd fit it!) will have problems with shrouding because the edge is so close to the cylinder wall. I think your machinist is making good choices. Good heads really make a tremendous difference on any engine, and the SBF is no exception. Like @Dan Babb said, your engine doesn't care that they are "bow tie valves", so long as they fit I'd like to know more about the rest of the engine choices he's making!
 
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