logo
12 Port News - Features
12 Port History
Casting Numbers
Online Store
Tech Tips
Become a Member
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 2 of 4 1 2 3 4
Joined: Sep 2008
Posts: 3,673
Likes: 42
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Sep 2008
Posts: 3,673
Likes: 42
To be honest, I don't think he even disassembles them before he scraps them. Im sure you could work something out with him to have them cleaned and magged, but im sure you'd have to pay for that 'cause he'll have too as well.



Class III CNC Machinist/Programmer
Joined: Feb 2014
Posts: 505
Major Contributor
Offline
Major Contributor
Joined: Feb 2014
Posts: 505
 Originally Posted By: Twisted6 I.I #3220
NOT a problem I'd take them. If they are not cracked and he really wants to part with them.

 Originally Posted By: CNC-Dude #5585
Correct, not every build is a race car, but every build using a 194 head will be shrouded except for a 194 engine, regardless of the power level. Tom's dyno tests showed and confirmed what these experts have been telling us for decades, that even in the 200-300 HP range the 194 head was already showing signs of the effects of shrouding. Larry, Tom will give you and ship you as many 194 heads as you can afford to pay the shipping for anytime you want them.....


I thought that was some kind of inside joke. I need an L6 head or two to practice on, and it's hard to find just a cracked junker locally to use the die grinder before I do it on the head I want to use. If I just have to pay for shipping, practicing on a 194 head is probably the best deal before I buy an open chamber head. I'll have to inquire.

Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
ok been researching the closed vs open chamber situation.

In general this is what I've learned:

1. open chamber heads typically flow more cfm
2. open chamber heads are typically lower compression
3. closed chamber heads typically flow less cfm
4. closed chamber heads are typically higher compression

that's probably stating the obvious at this point

It seems, in general, the closed chamber head (various makes/motors) is typically regarded as a performance head even at the sacrifice of head flow.

My question is why?

Quench; as I understand it, this is a desirable relationship and something that can be optimized in several ways to introduce swirl within the combustion chamber.

Using the 194 head on a 250, taking the intake valve shrouding out of the equations for a second, is it wrong to say in a stock 250 shortblock configuration, when the piston is at TDC, it is actually in the hole(i.e. not flush with cylinder deck height)whatever that amount is. Now using the typical FEL-PRO replacement gasket, would the closed chamber head would be desirable?

I guess my point is, is it possible to mitigate the short comings of the 194 head (the two I know of are the intake valve shrouding and cylinder bore size) so that I can take advantage of both the increase in compression and swirl effect? or am I just not understanding what's going on?

thoughts?


Last edited by moregrip; 02/22/14 08:24 PM.
Joined: Sep 2004
Posts: 5,840
Likes: 1
M
1000 Post Club
***
Offline
1000 Post Club
***
M
Joined: Sep 2004
Posts: 5,840
Likes: 1
I have had great results when running my 194 cyl head.

I had 12:1 compression on pump 91 octane, it also helped I had a positive deck height. Quench,& quench area had a big part of how I got to run 12:1 compression.

MBHD


12 port SDS EFI
Joined: Sep 2004
Posts: 5,840
Likes: 1
M
1000 Post Club
***
Offline
1000 Post Club
***
M
Joined: Sep 2004
Posts: 5,840
Likes: 1
[quote=CNC-Dude #5585 Larry, Tom will give you and ship you as many 194 heads as you can afford to pay the shipping for anytime you want them..... [/quote]

Seems a bit strange when I see on the 12 bolt sight he sells them, No where does it state he will not use, or refuse to use a 194 head.

The one he had on his sight sold, he must have twisted the customers arms forcing him to take it. LOL.


MBHD


12 port SDS EFI
Joined: Feb 2014
Posts: 505
Major Contributor
Offline
Major Contributor
Joined: Feb 2014
Posts: 505
 Originally Posted By: Mean buzzen half dozen A.K.A. Hank
I have had great results when running my 194 cyl head.

I had 12:1 compression on pump 91 octane, it also helped I had a positive deck height. Quench,& quench area had a big part of how I got to run 12:1 compression.

MBHD


Wow, that's a lot of compression. Was that with the .040" Fel Pro gasket? Did you deck it the 194 head to get less than 64cc chamber volume? I'm presuming this was a domed piston?

Joined: Sep 2004
Posts: 5,840
Likes: 1
M
1000 Post Club
***
Offline
1000 Post Club
***
M
Joined: Sep 2004
Posts: 5,840
Likes: 1
Just don't make no kind of sense even cleaning one of those heads would be just a waste, sarcasm. LOL \:D
And it sold for $1200.00?????? He should have given to Larry.

Not to mention this head was done after the famous dyno results.
Why bother with that 194 head w/such lousy results proven on the dyno?

Free bump to improve sales!!!

http://www.12bolt.com/250292_products/cylinder_heads_and_rocker_arms

Here is what it stated about his 194 head.


"Here is a head that has had the works thrown at it! This head will fit all 194, 215, 230 ,250 and 292 engines. This head will easily raise your compression by almost 1 point on a 250.

This head started out as a small chamber 194 head. The combustion chamber has been unshrouded around the intake valve to improve flow in this tight chamber.

This head has:

Casting has been hot tanked, Magnafluxed, and sandblasted.

New guides installed
Hardened exh seats installed
Factory rocker studs pulled, Stud boss's milled down
Screw in rocker studs (7/16)
1.84/ 1.60 valve sizes, Undercut stems, stainless construction
HIGH FLOW lump kit installed
Had street porting performed, This includes removing of excess material in valve bowl for the larger valves
Decked .030 Chamber size 70CC
High Performance springs setup for .550 lift Hydraulic cam
Lite weight retainers
3 angle performance valve job
Modern valve seals
Fully assembled"


12 port SDS EFI
Joined: Sep 2004
Posts: 5,840
Likes: 1
M
1000 Post Club
***
Offline
1000 Post Club
***
M
Joined: Sep 2004
Posts: 5,840
Likes: 1
[quote=LifeguardWow, that's a lot of compression. Was that with the .040" Fel Pro gasket? Did you deck it the 194 head to get less than 64cc chamber volume? I'm presuming this was a domed piston? [/quote]

.038" on the head gasket.
The 194 head was decked quite a bit. Chamber volume was in the 50s CC range IIRC. No unshrouding the chamber walls for better flow.

Flat top 307 SBC pistons w/4 valve reliefs.
Cranking compression was 220-230 PSI on all cylinders.
The pistons came out of the block, .002-.005" range

MBHD


12 port SDS EFI
Joined: Sep 2008
Posts: 3,673
Likes: 42
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Sep 2008
Posts: 3,673
Likes: 42
 Originally Posted By: Mean buzzen half dozen A.K.A. Hank
Just don't make no kind of sense even cleaning one of those heads would be just a waste, sarcasm. LOL \:D
And it sold for $1200.00?????? He should have given to Larry. It was probably the head off of the dyno engine.

Not to mention this head was done after the famous dyno results.
Why bother with that 194 head w/such lousy results proven on the dyno? Because people still want to believe myths and urban legends when they are told and proven they are wrong. So if they're are going to still be dumb enough to still spend their money on them, somebodies going to take their money...might as well be Tom.
If someone was going to pay me $1200 to prep one im not going to turn them away either...who would!

Free bump to improve sales!!!

http://www.12bolt.com/250292_products/cylinder_heads_and_rocker_arms

Here is what it stated about his 194 head.


"Here is a head that has had the works thrown at it! This head will fit all 194, 215, 230 ,250 and 292 engines. This head will easily raise your compression by almost 1 point on a 250.

This head started out as a small chamber 194 head. The combustion chamber has been unshrouded around the intake valve to improve flow in this tight chamber.

This head has:

Casting has been hot tanked, Magnafluxed, and sandblasted.

New guides installed
Hardened exh seats installed
Factory rocker studs pulled, Stud boss's milled down
Screw in rocker studs (7/16)
1.84/ 1.60 valve sizes, Undercut stems, stainless construction
HIGH FLOW lump kit installed
Had street porting performed, This includes removing of excess material in valve bowl for the larger valves
Decked .030 Chamber size 70CC
High Performance springs setup for .550 lift Hydraulic cam
Lite weight retainers
3 angle performance valve job
Modern valve seals
Fully assembled"



Class III CNC Machinist/Programmer
Joined: Sep 2008
Posts: 3,673
Likes: 42
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Sep 2008
Posts: 3,673
Likes: 42
 Originally Posted By: moregrip
ok been researching the closed vs open chamber situation.

In general this is what I've learned:

1. open chamber heads typically flow more cfm
2. open chamber heads are typically lower compression
3. closed chamber heads typically flow less cfm
4. closed chamber heads are typically higher compression

that's probably stating the obvious at this point

It seems, in general, the closed chamber head (various makes/motors) is typically regarded as a performance head even at the sacrifice of head flow. No, just the Chevy 6 cylinder head! SBC heads with small chambers are great flowing and very desirable for power increases, and they do.

My question is why? Because as I stated previously, they are trying to compare what works with a SBC and other engines and and assuming incorrectly it applies to the Chevy 6, and it doesn't!

Quench; in general it seems this is a desirable relationship and something that can be optimized in several ways to introduce swirl within the combustion chamber.

Using the 194 head on a 250, taking the intake valve shrouding out of the equations for a second, is it wrong to say in a stock 250 shortblock configuration, when the piston is at TDC, it is actually in the hole(i.e. not flush with cylinder deck height)whatever that amount is. Now using the typical FEL-PRO replacement gasket, would the closed chamber head would be desirable? The 194 closed chamber head will never be desirable on the 3.875" or larger bore engines. The open chamber head has great quench characteristics as do other performance and race closed chamber heads for the Chevy 6, just not the 194 head. The exhaust valve is also terribly shrouded in the 194 head also.

I guess my point is, is it possible to mitigate the short comings of the 194 head (the two I know of are the intake valve shrouding and cylinder bore size) so that I can take advantage of both the increase in compression and swirl effect? This heads chamber has no swirl effect in its design. or am I just not understanding what's going on? Your just not understanding that this heads chamber was only designed for the tiny 194 engine bore, thats why GM only put it on the 194. They knew this before anyone else did. Tom Langdon, one of Inliners senior inline 6 expert and former GM engineer that worked with these engines will even confirm that the 194 heads problems cannot be overcome when trying to use them on the larger bore engines.

thoughts?

Again, it people's incorrect assumptions and misunderstandings based on what works on the SBC and take all they know based on those engines and assume it works on the Chevy 6. They do make closed chamber heads that work great on the Chevy 6, but it isn't the 194 head. Its actually heads that have the chamber designed to be compatible with the larger bore of the 230,250 and 292 engines and are not shrouded. People have been trying to polish this turd into a diamond for almost 50 years....guess what it still is?
\:D

In the near 50 years the 194 head has been around, there have been many expert engine builders, professional head porters, GM engineers and many other professionals show countless evidence that the 194 head is very undesirable for any application other than being put on a 194 engine. In that same 50 years, there has never been any evidence show that to be the case for the open chamber head.....just sayin'!

One more thing then you can do what you like. Einstein has a famous saying: Insanity....repeating the same thing over and over again expecting different results!



Class III CNC Machinist/Programmer
Joined: Oct 2007
Posts: 5,041
Likes: 51
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Oct 2007
Posts: 5,041
Likes: 51
 Originally Posted By: moregrip
I currently have my stock 250 torn down to a short block in chassis. Motor is in a stepside short bed truck. Want to build a fun DD with decent power

Parts already purchased:

Clifford Intake manifold
Clifford Shorty headers
Weber 38/38 DGES 2 barrel carb (I believe it is rated at 380-390cfm)
Weber FPR
194 small chamber head

Parts/mods considering to complete build:

1.84I 1.6E valves with appropriate head work
Comp Cams 260H Cam kit(lifters/springs/timing gear) 212/212 .489/.489 on a 110LSA
Carter Electric Fuel Pump

Please critique my build plan


How are we doing? Is this what you were looking for?


"I wonder if God created man because he was disappointed in the monkey?" Mark Twain
Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
 Originally Posted By: Beater of the Pack


How are we doing? Is this what you were looking for?


lol, I'm somewhere in between sick to my stomach for wasting money on a 194 head and slightly optimistic.


Last edited by moregrip; 02/23/14 12:40 AM.
Joined: Oct 2007
Posts: 5,041
Likes: 51
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Oct 2007
Posts: 5,041
Likes: 51
Well you know how I feel. I have a 194 head and the same weirdness that makes me an inliner to begin with will probably cause me to use it some day. All of this has got me taking another look at the 194 as a whole. With the same outside measurements as the 230 & 250 and a 3.563 bore I wonder about cylinder wall thickness.


"I wonder if God created man because he was disappointed in the monkey?" Mark Twain
Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
No worries, truth be told, I love a good technical conversation. I haven't given up on this head 194 head yet; maybe I have a ringer!

I think I mentioned it earlier.....my buddy owns his own cylinder head shop so I may just go ahead and see if I can't talk him into a little extra effort and see what this thing flows bone stock. Then maybe modify one chamber, and retest. If improvement looks promising, then finish her up and run it, if not, well then I suppose I'll have more to think about.

Before I do any of that though I need to unwrap her and get a better look.



Off topic: I think I read from another thread where Hank had used the Balance Shop in Reseda for some of his work, well if that's the case, small world, I used him as well for an LS build back in 05.



Last edited by moregrip; 02/23/14 02:44 AM.
Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
I have to admit, based on your findings, my situation isn't looking very promising! In your tests how much power were you down using the 194 head vs everything else? Did you happen to post the data online? link?

Thank you!

Last edited by moregrip; 02/23/14 02:43 AM.
Joined: Sep 2008
Posts: 3,673
Likes: 42
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Sep 2008
Posts: 3,673
Likes: 42
moregrip, for your intended purpose you have nothing to fear with using the 194 head. Sure it might not give the engine all it can, but what really pisses me off if when people try to convince others something is better than something else based on urban legend or just bad info instead of facts. And that is what happens everytime this topic comes up. You have people that are never going to accept 50 years of fact and truth by professionals. And if someone wants to try to run one simply because they can thats fine. But know the facts and see if after you know them you still think the same way. If you do thats also fine as well.
But that is what forums are for, to share and give solid advice so those that might not be as knowledgeable can make good choices and be pleased with the choices they do make. Good luck, and don't let this get you down. Make sure you continue to share your progress with us as you complete your build.



Class III CNC Machinist/Programmer
Joined: Sep 2008
Posts: 3,673
Likes: 42
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Sep 2008
Posts: 3,673
Likes: 42
 Originally Posted By: moregrip
I have to admit, based on your findings, my situation isn't looking very promising! In your tests how much power were you down using the 194 head vs everything else? Did you happen to post the data online? link?

Thank you!


Tlowe has all the dyno test results. Or you might search thru the links of the dyno testing I posted a few days ago to find them.



Class III CNC Machinist/Programmer
Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
 Originally Posted By: CNC-Dude #5585
 Originally Posted By: moregrip
I have to admit, based on your findings, my situation isn't looking very promising! In your tests how much power were you down using the 194 head vs everything else? Did you happen to post the data online? link?

Thank you!


Tlowe has all the dyno test results. Or you might search thru the links of the dyno testing I posted a few days ago to find them.


thanks brother, I've been searching and reading like a mad man, was just hoping there might be a consolidated location, easier to compare apples to apples. Appreciate your insight even if I don't necessarily like it!! \:\) At least my eyes are open to what my obstacles could be!

Last edited by moregrip; 02/23/14 03:09 AM.
Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
 Originally Posted By: CNC-Dude #5585
moregrip, for your intended purpose you have nothing to fear with using the 194 head. Sure it might not give the engine all it can, but what really pisses me off if when people try to convince others something is better than something else based on urban legend or just bad info instead of facts. And that is what happens everytime this topic comes up. You have people that are never going to accept 50 years of fact and truth by professionals. And if someone wants to try to run one simply because they can thats fine. But know the facts and see if after you know them you still think the same way. If you do thats also fine as well.
But that is what forums are for, to share and give solid advice so those that might not be as knowledgeable can make good choices and be pleased with the choices they do make. Good luck, and don't let this get you down. Make sure you continue to share your progress with us as you complete your build.


Like I said, I do appreciate it......still researching.....I'm sort of a OCD research-aholic. I will definitely provide updates and share what I find. thank you!

Joined: May 2009
Posts: 493
S
Contributor
*****
Offline
Contributor
*****
S
Joined: May 2009
Posts: 493
I suppose you could sleeve your block down to a 194 bore size \:\)

Joined: Oct 2007
Posts: 5,041
Likes: 51
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Oct 2007
Posts: 5,041
Likes: 51
When tlowe did the dyno tests he asked for help in the form of donations. those who donated got copies of the results as a thank you. As far as I'm concerned it would be good to post the full results here for all to see and debate. For my part the money I sent would have been turned into urine long ago and is of no importance any more. As to this discussion it is the job of the knowledgeable to sort fact from fiction. It is my job to see that future pundits have stuff to sort. \:\)


"I wonder if God created man because he was disappointed in the monkey?" Mark Twain
Joined: Nov 2013
Posts: 482
I
Contributor
*****
Offline
Contributor
*****
I
Joined: Nov 2013
Posts: 482
If a 194 had enough wall thickness which I don't think it does one could bore it out to3.740 and use stock 305 pistons. The new Vortec pistons are pretty good. Just a thought. Jay 6155

Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
 Originally Posted By: strokersix
I suppose you could sleeve your block down to a 194 bore size \:\)


lol, I imagine that would be $$$$

Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
 Originally Posted By: Beater of the Pack
When tlowe did the dyno tests he asked for help in the form of donations. those who donated got copies of the results as a thank you. As far as I'm concerned it would be good to post the full results here for all to see and debate. For my part the money I sent would have been turned into urine long ago and is of no importance any more. As to this discussion it is the job of the knowledgeable to sort fact from fiction. It is my job to see that future pundits have stuff to sort. \:\)


I think I have a legitimate part time job researching and sorting !

BTW, I was just in Nevada last week for work, Fallon to be exact!

Last edited by moregrip; 02/23/14 02:03 PM.
Joined: Feb 2014
Posts: 505
Major Contributor
Offline
Major Contributor
Joined: Feb 2014
Posts: 505
 Originally Posted By: intergrated j 78
If a 194 had enough wall thickness which I don't think it does one could bore it out to3.740 and use stock 305 pistons. The new Vortec pistons are pretty good. Just a thought. Jay 6155


You could sleeve a 250 block and then bore it out to 3.740" for a 305 piston. GM flipped the idea of a wide bore and short stroke of the 307, to the narrower bore and longer stroke of the 305 (using a 262 bore with a 350 stroke), which supposedly is better at making more torque for the same engine size. But the 250 stroke is longer than 3.48", so maybe it might equal out power-wise with the 250?

Joined: Oct 2007
Posts: 5,041
Likes: 51
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Oct 2007
Posts: 5,041
Likes: 51
I just wonder if the 194 walls might be a little thicker and be able to handle more boost than the other blocks.


"I wonder if God created man because he was disappointed in the monkey?" Mark Twain
Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
Ok, I went ahead and purchased the Power Manual 2nd edition for Kindle and nearly read the whole damn thing. Great info! According to what I read I think I'm going to be just fine with the 194 head even if I'm down a few HP. Lot's of great info in there! T6Racing very highly regarded among others!

Last edited by moregrip; 02/23/14 11:16 PM.
Joined: Apr 2004
Posts: 3,566
Likes: 37
1000 Post Club
****
Online Content
1000 Post Club
****
Joined: Apr 2004
Posts: 3,566
Likes: 37
Just plan on doing a little more work to the 194 head. Like I said earlier, unshroud the chamber around the intakes and the exhaust wall side, enlarge the valves and perform some porting. It will work out great.

It is harder to find a uncracked casting, and opening the valves to a 1.94" intake is risking hitting water on these "194" heads. Especially for people not familiar with doing work to the inline heads.

It is just extra work that would not have to be done to a open chambered head to get the same performance.

I am currently working on one now for a customer and will try and post up some pics. It is being setup with 1.94/ 1.6 valves.


Inliner Member 1716
65 Chevelle Wagon and 41 Hudson Pickup
Information and parts www.12bolt.com

Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
 Originally Posted By: tlowe #1716
Just plan on doing a little more work to the 194 head. Like I said earlier, unshroud the chamber around the intakes and the exhaust wall side, enlarge the valves and perform some porting. It will work out great.

It is harder to find a uncracked casting, and opening the valves to a 1.94" intake is risking hitting water on these "194" heads. Especially for people not familiar with doing work to the inline heads.

It is just extra work that would not have to be done to a open chambered head to get the same performance.

I am currently working on one now for a customer and will try and post up some pics. It is being setup with 1.94/ 1.6 valves.


After reading the book there is certainly more I want to do straight out of the shoot, more deburring in general, matching the port openings to Fel Pro gasket on the head and Clifford intake manifold, polish intake ports with 40grit, clean up combustion chamber/exhaust port with 80grit, and of course unshroud valves.

Thanks for the advice! Much appreciated!

Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
Also, the flow data enclosed in the power book is very promising! Kinda surprising the potential theses heads have.

My next question is that in lieu of performing the lump port mod they talked about modifying the bolt boss in the intake port like a "wing", can someone explain this a bit better? Anything I can do labor based will save me $$ in this build.

Joined: Sep 2008
Posts: 3,673
Likes: 42
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Sep 2008
Posts: 3,673
Likes: 42
Your best bang for the buck is going to be to fully remove the bolt boss compared to leaving it intact, but reshaping it. Tom dyno tested that mod on several engines and saw no additional gains between the bolt boss untouched vs. tapered or "wing" shaped. So no, that mod doesn't give you any benefits.
Try to find the thread for the 292 dyno tests, it has a wealth of info in it and can connect the dots to many questions you might have. Titen really should have made those and the 250 dyno tests a sticky because they keep getting lost in the archives.



Class III CNC Machinist/Programmer
Joined: Feb 2014
Posts: 505
Major Contributor
Offline
Major Contributor
Joined: Feb 2014
Posts: 505
 Originally Posted By: CNC-Dude #5585
Your best bang for the buck is going to be to fully remove the bolt boss compared to leaving it intact, but reshaping it. Tom dyno tested that mod on several engines and saw no additional gains between the bolt boss untouched vs. tapered or "wing" shaped. So no, that mod doesn't give you any benefits.
Try to find the thread for the 292 dyno tests, it has a wealth of info in it and can connect the dots to many questions you might have. Titen really should have made those and the 250 dyno tests a sticky because they keep getting lost in the archives.


Yeah, my budget plan after I read his cylinder chapter was to do the valve work and cleanup to get the flow numbers that the flowchart for the Kramer head got. But I was scratching my head at what he meant by "wing shaped". Plane wings are not symmetrical in cross-sectional shape, so I assumed he meant to shape the boss like a teardrop. Taking material off on either side and then bringing to a point on the leading edge. But I'm not sure if there is enough material on the boss to create this shape? I think I'll just take the casting flash off the bosses and intake ports leaving the ports the stock size to maximize velocity with a good valve job.

Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
Understood, I'll start saving my pennies for the lump port mod!

Joined: Aug 2013
Posts: 78
M
Active BB Member
OP Offline
Active BB Member
M
Joined: Aug 2013
Posts: 78
 Originally Posted By: Lifeguard
 Originally Posted By: CNC-Dude #5585
Your best bang for the buck is going to be to fully remove the bolt boss compared to leaving it intact, but reshaping it. Tom dyno tested that mod on several engines and saw no additional gains between the bolt boss untouched vs. tapered or "wing" shaped. So no, that mod doesn't give you any benefits.
Try to find the thread for the 292 dyno tests, it has a wealth of info in it and can connect the dots to many questions you might have. Titen really should have made those and the 250 dyno tests a sticky because they keep getting lost in the archives.


Yeah, my budget plan after I read his cylinder chapter was to do the valve work and cleanup to get the flow numbers that the flowchart for the Kramer head got. But I was scratching my head at what he meant by "wing shaped". Plane wings are not symmetrical in cross-sectional shape, so I assumed he meant to shape the boss like a teardrop. Taking material off on either side and then bringing to a point on the leading edge. But I'm not sure if there is enough material on the boss to create this shape? I think I'll just take the casting flash off the bosses and intake ports leaving the ports the stock size to maximize velocity with a good valve job.


I interpreted the wing as a tear drop shape as well.....may just be easier to go with the "lump" after-all.

Joined: Sep 2004
Posts: 5,840
Likes: 1
M
1000 Post Club
***
Offline
1000 Post Club
***
M
Joined: Sep 2004
Posts: 5,840
Likes: 1
Just think of making the port window bigger.
If you can make the window bigger it should flow more.

I would not make the sides of the port bigger, I would grind down the bosses, if you are going to keep the bosses & not go w/lump ports.

Nothing here was ever posted on what Tom did to his 250-292 dyno heads.

Who knows how much material was removed from the bosses?
What were his final dimensions of the intake ports?

Like I said before, you cannot think of his dyno results are the final say so on every configuration on how our inline 6's react with different techniques of porting, different valve jobs, throat angles, camshafts, carbs, intake mainfolds, etc etc & so-on.

They just give you of his results. Good basic results.

Other people have had different results than his dyno tests, and other dyno tests will different results also.

Dyno results will also give you different result when the engine is put into a vehicle. Could be better than expected, could be worse. Point is, you just do not know until the engine is put into a moving working chassis.

What works on a dyno does not absolutely mean it will work in a chassis the same way.

Don't take it the wrong way, dynos are a great tool for tuning,, a chassis dyno is even a better way to tune for real world street & race tuning IMO.

They all have a place to get good feedback on how different combos work & what will not possibly work.

A great flowing head can be an absolute dog of an engine for driven daily driver. This great flowing head on a flow bench can look great on an engine dyno, but it could be a pig when actually installed into a car/truck or?

MBHD


12 port SDS EFI
Joined: Aug 2006
Posts: 232
W
Contributor
*****
Offline
Contributor
*****
W
Joined: Aug 2006
Posts: 232
If I recall correctly, enlarging the valves to at least 1.86"/1.6" intake/exhaust was one of the biggest gains. The bolt-in lumps gave a 5 - 7 hp gain throughout the entire rpm range. The lumps didn't provide any benefit till the valves were enlarged.

One thing that "just bugs me" about the 250 large combustion chamber, is the overlap of the combustion chamber with the deck surface of the cylinder block. This cannot be conducive to flow. And, I am not partial to grinding and tapering the top edge of the cylinder wall. The 194 combustion chamber should be able to avoid this. To help reduce this overlap with the large combustion chamber, offset cylinder head dowel pins have been used by some. However, I have not found a source for cylinder head dowel pins with offsets of greater than 0.030". In the Power Manual, one engine builder gave offsets of 0.060" to 0.090".

Joined: Sep 2008
Posts: 3,673
Likes: 42
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Sep 2008
Posts: 3,673
Likes: 42
Winter, the chamber overhang is negligible and is dictated by the core shift of the block and/or head of each engine. Not all of them even have an issue. But notching the cylinders for valve clearancing and enhanced breathing is one of those "hidden" speed secrets that all engine builders do that the average hobbyist might not know to do, or is skeptical about performing. We used 2.150" intake valves and 1.625" exhaust valves in our heads and didn't offset the head. That is one of those mods that isn't necessary and was probably concieved out of imitation from some other engine type, while truly important other mods were overlooked, but stuck in someones mind as being critical when it isn't.
The chamber on the 194 head places the chamber in the opposite direction from the cylinder wall and too far away to be corrected and will shroud both the intake and exhaust more than can be gained by attempting to unshroud it. It simply can't be undone regardless of the effort put into it.
GM, all the top 6 cylinder engine builders and head porters, GM engineers like Tom Langdon and countless top racers have known that about the 194 head and have shown and proven it for decades. Why is that so hard to accept.
We were part of that crowd as well at one time and like others, did some good things with the 194 head. But once the advantages of the open chamber head were discovered, there became no point in persuing it any longer, as many others discovered that as well. At our level of power, this was about a 45-50 HP gain over the 194 head. Tom showed about a 10 HP gain with the open chamber head across the entire RPM range, even after unshrouding the 194 head. So bottom line is, you will do more and spend more, but get less with the 194 head. So everyone got to see first hand that this was confirming what all the top guys had been saying all this time.



Class III CNC Machinist/Programmer
Joined: Aug 2006
Posts: 232
W
Contributor
*****
Offline
Contributor
*****
W
Joined: Aug 2006
Posts: 232
CNC-Dude, I am not partial to either head. I have one of each, with the 194 just setting. I'm not arguing with the general consensus of the 250 head flowing better. But I do wonder a little if Twisted6Larry or Mean-Buzzen Half-Dozen Hank didn't do something slightly different with their 194 heads, that these other guys didn't try. I do have a copy of the dyno run results by Tom Lowe, which are very informative.

On the photos of modified 194 heads that I have seen, none have the extent of de-shrouding that follows the current trends of cardioid, kidney, or figure 8 combustion chambers. Is this due to lack of wall material in the combustion chamber before hitting the cooling jacket, on the spark plug side of the intake valves?

Joined: Jul 2000
Posts: 4,588
Likes: 20
1000 Post Club
**
Online Content
1000 Post Club
**
Joined: Jul 2000
Posts: 4,588
Likes: 20
Something else they used to do was shave the heads on a angle. Cutting more of the spark plug side and then re-drilling the head both holes.


Larry/Twisted6
[oooooo] smile
Adding CFM adds boost smile
shocked God doesn't like ugly.
Joined: Sep 2008
Posts: 3,673
Likes: 42
1000 Post Club
****
Offline
1000 Post Club
****
Joined: Sep 2008
Posts: 3,673
Likes: 42
 Originally Posted By: Winter
On the photos of modified 194 heads that I have seen, none have the extent of de-shrouding that follows the current trends of cardioid, kidney, or figure 8 combustion chambers. Is this due to lack of wall material in the combustion chamber before hitting the cooling jacket, on the spark plug side of the intake valves?

Because the chamber was designed for such a small cylinder bore, the material available in the casting to unshroud it is too limited to actual accomplish it. And being able to create these newer modern chamber shapes just isn't able to be accomplished. It isn't with the open chamber head either, but you also don't have the shrouding problem either.

As far as them trying something different than these other guys. These other guys being Kay Sissell, Jim Headrick, Glen Self, Tom Langdon and General Motors....do you really want to hear my answer!LOL

I can tell you what Hank didn't do, and that is try the same mods on the open chamber head as he did the 194 head. He went from 9-1 compression on the open chamber head and increased the compression with the 194 head to 12-1. And then added side draft carbs and changed cams but gave all the credit to his gain to the head....Not a very accurate comparison! If he had then repeated those mods on the open chamber head and compared it equally at 12-1 compression he would have a different prospective. Yes he got good results with 12-1 compression with the 194 head, but he would have still been leaps and bounds ahead of the game with the open chamber head if he had done the same with it.



Class III CNC Machinist/Programmer
Page 2 of 4 1 2 3 4

Moderated by  stock49, Twisted6, will6er 

Link Copied to Clipboard
Who's Online Now
0 members (), 125 guests, and 27 robots.
Key: Admin, Global Mod, Mod
Newest Members
Hairyclive, THarper, crash, ocean1907, Jabez House
6,816 Registered Users
Sponsored Advertisement
Sponsored Advertisement
This Space is Available
Powered by UBB.threads™ PHP Forum Software 7.7.5