50 degree valve seats in modern hot street builds: is it finally time?

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groberts101
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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by groberts101 » Tue Jun 12, 2018 7:40 am

statsystems wrote:
Mon Jun 11, 2018 10:17 pm
No one is pushing anything. What you want is a single answer and there isn't one. There are several 50* seat cutters. There is no one fits all.

That is exactly what I said way back in this thread. You want someone to hand hold you through the whole process. That's rediculous.

Again, remember what Darin Morgan said...he still uses 1.88 exhaust valves because that's what people wanted. I suspect the same thing happens with valve jobs.

Stay with the 45 on everything. You'll be happier.
Yes you are pushing like you have an agenda to get the word out about how smart and ahead of the curve you've been for the past 20 years. And you obviously have no idea what I want. If you did and had the info.. I'm pretty sure you or someone else would have posted it by now. Guidelines.. trends.. rules of thumb.. why would anyone misinterpret any of those terms to be highly specific to require handholding? There are bits and pieces of pertinent info floating around through dozens of pages but most of it has been rhetoric and buried by personal bias. Not to mention no one here has said anything even remotely new or spelled out recipe's to be used on mainstream parts with mainstream cams. Like I said above.. you'd all be much further ahead in the cause if you posted full build recipe's with dyno or track results.

No offense intended here.. but constantly saying "It works.. so just do it!.. but.. you have to test and retest any maybe test again to get it right. Oh, but it won't work on that mainstream AFR sbc casting and you should have a better cam too" doesn't do much for most street guys looking to clear up this subject.

And for god sakes man, just because someone doesn't feel the urge to jump headfirst into modifications for which they have little experience, and that may or may not be fully reversible, doesn't even come close to being scared of something. I'd call that prudent to protecting an investment of hard earned cash by not trying something new to them when an educated guess cannot be fully relied upon. I use the internet to gain perspectives and see trends based on others experiences.. but it's still up to me to weed through all the bs and implement any newly aquired "puzzle piece" knowledge into my own stuff. And 50's or 55's being used across the world on every conceivable combination of parts is far from a solid and well proven trend. People generally are stubborn sheep and don't change until the results are overwhelmingly in their favor. This stuff is like stock investing.. the market will bear what it can.. and this subject is far from proven to be a big money maker for all street cars so far.

Anywho.. with all the posturing and personalized crap burying.. doesn't seem to be much more to be gained in these particular threads by asking qurstions. So I'll continue to pop in and read to find the info as it gets spread out over another hundred pages or more in this thread and others like it. Thanks to those who've posted the useful bits and pieces so far.

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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by DrillDawg » Tue Jun 12, 2018 8:39 am

groberts101 wrote:
Tue Jun 12, 2018 7:40 am
statsystems wrote:
Mon Jun 11, 2018 10:17 pm
No one is pushing anything. What you want is a single answer and there isn't one. There are several 50* seat cutters. There is no one fits all.

That is exactly what I said way back in this thread. You want someone to hand hold you through the whole process. That's rediculous.

Again, remember what Darin Morgan said...he still uses 1.88 exhaust valves because that's what people wanted. I suspect the same thing happens with valve jobs.

Stay with the 45 on everything. You'll be happier.
Yes you are pushing like you have an agenda to get the word out about how smart and ahead of the curve you've been for the past 20 years. And you obviously have no idea what I want. If you did and had the info.. I'm pretty sure you or someone else would have posted it by now. Guidelines.. trends.. rules of thumb.. why would anyone misinterpret any of those terms to be highly specific to require handholding? There are bits and pieces of pertinent info floating around through dozens of pages but most of it has been rhetoric and buried by personal bias. Not to mention no one here has said anything even remotely new or spelled out recipe's to be used on mainstream parts with mainstream cams. Like I said above.. you'd all be much further ahead in the cause if you posted full build recipe's with dyno or track results.

No offense intended here.. but constantly saying "It works.. so just do it!.. but.. you have to test and retest any maybe test again to get it right. Oh, but it won't work on that mainstream AFR sbc casting and you should have a better cam too" doesn't do much for most street guys looking to clear up this subject.

And for god sakes man, just because someone doesn't feel the urge to jump headfirst into modifications for which they have little experience, and that may or may not be fully reversible, doesn't even come close to being scared of something. I'd call that prudent to protecting an investment of hard earned cash by not trying something new to them when an educated guess cannot be fully relied upon. I use the internet to gain perspectives and see trends based on others experiences.. but it's still up to me to weed through all the bs and implement any newly aquired "puzzle piece" knowledge into my own stuff. And 50's or 55's being used across the world on every conceivable combination of parts is far from a solid and well proven trend. People generally are stubborn sheep and don't change until the results are overwhelmingly in their favor. This stuff is like stock investing.. the market will bear what it can.. and this subject is far from proven to be a big money maker for all street cars so far.

Anywho.. with all the posturing and personalized crap burying.. doesn't seem to be much more to be gained in these particular threads by asking qurstions. So I'll continue to pop in and read to find the info as it gets spread out over another hundred pages or more in this thread and others like it. Thanks to those who've posted the useful bits and pieces so far.


For someone who types the longest posts and seems to want to dominate what people have to say........
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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by Warp Speed » Tue Jun 12, 2018 8:52 am

LOL

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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by groberts101 » Tue Jun 12, 2018 9:00 am

DrillDawg wrote:
Tue Jun 12, 2018 8:39 am
For someone who types the longest posts and seems to want to dominate what people have to say........
Lol.. now not only can I choose not to agree with every single word the "status quo group" posts around here.. but I'm also an internet bully too. I'm scared to run 50's so I hide behind keyboards and try to make myself feel superior to my superiors? :-k I'll have to ponder that one a bit to figure things out. :roll:

You may not have posted much proven and fact based info with data to back it all up to help others on this subject.. but you're quite the sprouting psychologist! =D>

I also have to wonder sometimes.. if people following to closely to one another on internet forums suddenly stop.. do they still get brown noses? :lol:

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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by Frankshaft » Tue Jun 12, 2018 9:07 am

Groberts, do this if you want to try a 50. I can tell you do, but part of you doesn't want to ruin your heads, I know that's what your thinking. So, cut a 50 on your existing valve size. 2.02 right? 40-50-65-78-82. Blend 82 into 78 and size throat at 1.84 inch which is 91%. Run it. If it's a pooch, or makes less power than you hoped for, then you could simply pull the heads, re cut seats for a 2.055 intake. That's not to big for your 4+ inch bore. Cut a traditional 45 seat, something like 38-45-60-75, and it should just "fit" in like it was meant for it. Leave the throat alone. The 1.84 is now like 89.5% of a 2.055. And it will at least tell you the tale. What do you think? Or do both, then if it turns out the 50 was better, recut it for the 2.055 valve. 👍 That would be the least intrusive to your heads, and won't ruin them in any way. I would have a 2.055 in that head anyhow.
Last edited by Frankshaft on Tue Jun 12, 2018 9:13 am, edited 2 times in total.

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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by DrillDawg » Tue Jun 12, 2018 9:10 am

groberts101 wrote:
Tue Jun 12, 2018 9:00 am
DrillDawg wrote:
Tue Jun 12, 2018 8:39 am
For someone who types the longest posts and seems to want to dominate what people have to say........
Lol.. now not only can I choose not to agree with every single word the "status quo group" posts around here.. but I'm also an internet bully too. I'm scared to run 50's so I hide behind keyboards and try to make myself feel superior to my superiors? :-k I'll have to ponder that one a bit to figure things out. :roll:

You may not have posted much proven and fact based info with data to back it all up to help others on this subject.. but you're quite the sprouting psychologist! =D>

I also have to wonder sometimes.. if people following to closely to one another on internet forums suddenly stop.. do they still get brown noses? :lol:


.......most hoarders are in denial too.....just like you they are not going to change......
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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by randy331 » Tue Jun 12, 2018 9:15 am

paulzig wrote:
Mon Jun 11, 2018 4:54 pm
randy331 wrote:
Mon Jun 11, 2018 10:45 am


Your familiar with pseudo, that's the one I've had in the back of my mind to do a valve job test on some day. It's still the GM valve job and 2" valve, so options are open on what can be done.

Randy
Trying it on pseudo 383 sounds like a good idea just the 50 cut on IN and EX is enough to see a trend. Dont have to go spending 1000s on magic camz or flowing heads the cam is on 108LSA people should be happy with that.

It already made really good power with the stock GM valve job.
There would be those that would discredit the test, saying a better 45* would have done better or with xxx flowz speced cam the other valve job would be better.

A test more interesting to me would be do some window area figuring and use a larger valve with the steeper seats. That's kinda how I view the use of seat angles. What else it lets you do. (better compromise)

Randy

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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by groberts101 » Tue Jun 12, 2018 9:21 am

Frankshaft wrote:
Tue Jun 12, 2018 9:07 am
Groberts, do this if you want to try a 50. I can tell you do, but part of you doesn't want to ruin your heads, I know that's what your thinking. So, cut a 50 on your existing valve size. 2.02 right? 40-50-65-78-82. Blend 82 into 78 and size throat at 1.84 inch which is 91%. Run it. If it's a pooch, or makes less power than you hoped for, then you could simply pull the heads, re cut seats for a 2.055 intake. That's not to big for your 4+ inch bore. Cut a traditional 45 seat, something like 38-45-60-75, and it should just "fit" in like it was meant for it. Leave the throat alone. The 1.84 is now like 89.5% of a 2.055. And it will at least tell you the tale. What do you think?
I think that's the kind of info I was after here all along, always have been before I ever signed up, and wish more people would spell out in their posts about these types of subjects. I don't consider that hand holding at all.. just an elaboration of recipe.

And I did have that as a back up plan if not wanting to pull seats and add weld. Probably still add weld. Like stat and others mentioned a few times.. either put a bigger valve to close up the choke % or run a 50 to match the too big choke and better idealize the relationship. Which I'm certainly not scared to do but if things get that time involved I'll just sell em' and move onto my P38's till my aluminum block deal is finalized.

Not worried about the valve to bore sizing, plus these heads have revised/twisted valve locations so more wiggle room there anyways. Here's my main concern, and feel free to correct my logic, despite the smaller choke %, wouldn't a 2.055" valves larger/faster curtain expisure work against me at slower piston speeds for lower speed torque output on a 3" stroke deal?

That's the main reason I chose not to run my 2.1" valved P38's on this smaller motor.

PS. My other thought if running the larger intake valve on a smaller cam'd street motor like this was to shrink the exhaust downwards of 1.5" and run a 50 to get a better choke size with smaller 1.5" primary before the first header step. Might help reduce reversion and crutch the faster opening curtain area to keep torque up and snappier down low.
Last edited by groberts101 on Tue Jun 12, 2018 9:42 am, edited 1 time in total.

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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by CGT » Tue Jun 12, 2018 9:39 am

randy331 wrote:
Tue Jun 12, 2018 9:15 am
There would be those that would discredit the test, saying a better 45* would have done better or with xxx flowz speced cam the other valve job would be better.

A test more interesting to me would be do some window area figuring and use a larger valve with the steeper seats. That's kinda how I view the use of seat angles. What else it lets you do. (better compromise)
That's why the more I think about it, I would just do the test and keep it private. I've thought about it, there isn't a set of tests that wont get you picked apart by people while your feeding them free data. What's the point?

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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by groberts101 » Tue Jun 12, 2018 9:50 am

CGT wrote:
Tue Jun 12, 2018 9:39 am
randy331 wrote:
Tue Jun 12, 2018 9:15 am
There would be those that would discredit the test, saying a better 45* would have done better or with xxx flowz speced cam the other valve job would be better.

A test more interesting to me would be do some window area figuring and use a larger valve with the steeper seats. That's kinda how I view the use of seat angles. What else it lets you do. (better compromise)
That's why the more I think about it, I would just do the test and keep it private. I've thought about it, there isn't a set of tests that wont get you picked apart by people while your feeding them free data. What's the point?
I bet you're right about not pleasing everyone but who cares about that either, right? Test for yourself to see trends that can be used towards improving your own engine building. And if you're the sharing type?.. great for you and others who may learn from that data. If not.. go make more money with it and let everyone else go their own way at their own pace. Nothing changes but your bank account. :wink:

Personally, I think it's a valid test to show flowpath and velocity improvements to be gained from the steeper seats. Eliminate much of the variables in the curtain size differences between those 2 and you'll more closely refine what does what to what within the power curve. Then you're down to choke sizing and flowpath improvements becoming the dominant factors with less blurry emphasis on reduced window sizing at beginning and end lift points.
Last edited by groberts101 on Tue Jun 12, 2018 9:54 am, edited 1 time in total.

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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by n2xlr8n » Tue Jun 12, 2018 9:54 am

Rick360 wrote:
Mon Jun 11, 2018 9:52 pm
Here's a link to an old Speedtalk thread from 2005 that might be useful for some. This post/thread was my initial inspiration as to a new reason other than flow "why" steeper seats might be better, although I already had a set of heads with 50º seats by then. This certainly got me thinking along new lines.

http://www.speedtalk.com/forum/viewtopic.php?f=1&t=1257

Rick

Yes- one my favorites. It also shows how you/they arrived at the conclusions in the thread, working together.

A notable quote that newer folks on the site should read (from a brilliant old school guy):
bill jones wrote:
Mon Jul 04, 2005 11:24 pm
-But you know, all of us aren't educated to where we know what we (and you educated people) are doing, so we have to try some idea that we can understand and believe.
-That's what's neat about these websites is there is all sorts of good thinking going on and most of us make do with what we have available regardless of what someone else has or does.
He who is in me is greater than he who is in the world.

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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by groberts101 » Tue Jun 12, 2018 10:03 am

n2xlr8n wrote:
Tue Jun 12, 2018 9:54 am
Rick360 wrote:
Mon Jun 11, 2018 9:52 pm
Here's a link to an old Speedtalk thread from 2005 that might be useful for some. This post/thread was my initial inspiration as to a new reason other than flow "why" steeper seats might be better, although I already had a set of heads with 50º seats by then. This certainly got me thinking along new lines.

http://www.speedtalk.com/forum/viewtopic.php?f=1&t=1257

Rick

Yes- one my favorites. It also shows how you/they arrived at the conclusions in the thread, working together.

A notable quote that newer folks on the site should read (from a brilliant old school guy):
bill jones wrote:
Mon Jul 04, 2005 11:24 pm
-But you know, all of us aren't educated to where we know what we (and you educated people) are doing, so we have to try some idea that we can understand and believe.
-That's what's neat about these websites is there is all sorts of good thinking going on and most of us make do with what we have available regardless of what someone else has or does.
Yep.. less posturing and more sharing despite minor disagreements on certain aspects of design and theory. A disagreement is not a personal attack like some will quickly respond to. Well, at least until they add some personal attack in there. lol It's just a simple difference of opinion based on experiences and perception of what is being said by all involved. Texting sucks these days.. far too much misinterpretation.

And Bill's posts are great.. I read every single one I can find because I come from that same school myself.. just graduated about 15 years later is all. Case in point. I recently wetsanded my block with a 3/8" plate of glass covered with sandpaper because the machine shop didn't get the friggin' RA right for use with my Cometics even though I specifically told them what I was using and wanted. Old school still works.. people just get used to pushing buttons and walking away and forget that there are many ways to skin the same cat.

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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by DrillDawg » Tue Jun 12, 2018 10:33 am

groberts101 wrote:
Tue Jun 12, 2018 7:40 am
statsystems wrote:
Mon Jun 11, 2018 10:17 pm
No one is pushing anything. What you want is a single answer and there isn't one. There are several 50* seat cutters. There is no one fits all.

That is exactly what I said way back in this thread. You want someone to hand hold you through the whole process. That's rediculous.

Again, remember what Darin Morgan said...he still uses 1.88 exhaust valves because that's what people wanted. I suspect the same thing happens with valve jobs.

Stay with the 45 on everything. You'll be happier.
Yes you are pushing like you have an agenda to get the word out about how smart and ahead of the curve you've been for the past 20 years.
Just like Frankshaft, he understood your fear and then told you just what you did not want to hear, then you .......
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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by CGT » Tue Jun 12, 2018 10:46 am

30 degree seat. 100k plus life expectancy in OE applicatons. Probably 1/2 that in a performance street strip app
45 degree seat. I've seen several hundred thousand in OE applications " "
50 degree seat 10 minute life expectancy in street strip application? :D
55 degree seat 3 minute life expectancy? ](*,)

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Re: 50 degree valve seats in modern hot street builds: is it finally time?

Post by Frankshaft » Tue Jun 12, 2018 11:05 am

CGT wrote:
Tue Jun 12, 2018 10:46 am
30 degree seat. 100k plus life expectancy in OE applicatons. Probably 1/2 that in a performance street strip app
45 degree seat. I've seen several hundred thousand in OE applications " "
50 degree seat 10 minute life expectancy in street strip application? :D
55 degree seat 3 minute life expectancy? ](*,)

Pretty sure your being sarcastic? 55 degree seats last just fine, and much longer than that. Same with 50 degree seats. Even 60's will.

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