Inliners International Forums General Discussion Hi Performance your thoughts on my build plans

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

Sounds like a decent plan. On the 194 head, many that I do are cracked. Get some unshrounding done around the intake valves. Other wise there will be no gain with the higher compression head.

thanks for the reply. I purchased the head from a gentleman on ebay who deals with chevy inlines exclusively (mrhotrod I believe)....anyway the head was magnafluxed and surfaced as well as cleaned up very nicely. I appreciate the insight and I will double check for cracks here locally.

Your head from Mrhotrod6 will just as he says. They are checked Before and after any work is done to them. Just to be sure they are at 100% before going out the door.

I did gain a bunch more power when I switched over to a 194 head.

Mainly because of the increased compression.

9:1 to 12:1 compression, what a difference in power!
Sure glad I switched to a 194 head.

MBHD

Im fixing to hurt your feeling real bad Hank. I have a Sissell catalog that has his thoughts and test findings about the 194 head and actual articles he personally wrote and had published in Hot Rod magazine and other publications about the use of that head. Im scanning it right now and will add it tonight when I get it formatted. He was very Anti-194 head oriented and tested hundreds of them in his time in every configuration they could have been modified.

With me reading the results from Kay would not hurt my feelings one bit. I love a good read.
The 194 head was head & shoulders above my 250 head, track tested & street race proven. Just stating my facts.

Everybody's results will differ.

Mike Kirby likes the 194 head & he was Sissells right hand man, correct?

MBHD

Your results were heads and shoulders above the open chamber head because you performed mods that were heads and shoulders above what you did to the open chamber head. If you had done the same mods to the open chamber head and obtained the same compression, you would have a different opinion. You never compared the different heads on a one to one basis to know which is the better head.

Kirby was his right hand man and stepped into Sissell's shoes, but by no means did he fill them.

My 250 head had a 1.9" intake & 1.6" exhaust valves, mild bowl porting, chambers untouched.

My 194 head had 1.88" intake & 1.6" exhaust valves minor bowl porting & chambers untouched.

My cranking compression was 150-160 psi w/the 9:1 250 head & 220-230 PSi cranking compression w/the 194 head.

The 194 head was shaved quit a bit.

Both heads were similar in porting but the 250 head had a little bit larger intake valve.

With having 220-230 cranking compression w/the 194 head, the low end torque was very apparent (over the 250 head), & was a real stump puller.

The heads were swapped onto the same short block. Back to back.

I might be able to flow test the 194 head, I am sure it did not flow well @ all, never did I use lump ports.

MBHD

Were the bolt-in lumps available at the time you built this engine?

Different article, but basically says the same thing as the previous one about why not to use the 194 head. These were taken from his catalog for Sissell Automotive and were articles he wrote personally in Hot Rod Magazine and the National Dragster.

Hank,

What cam were you using?

Fuel burned and actual dynamic compression ratio are the two big factors for engine power/torque and efficiency.

To bad we can't read them.

But interesting is that it says weber's will give 60hp over multi carb set-ups.

That was once thought to be true, but when Headrick switched to(3)Holleys and picked up 40 HP and .2 tenths of a second in the quarter, every body else that was running Webers quit using them and switched to Holley's also.

The section about cylinder heads in the article starts off by saying, "Any head except the one for the 194 engine is a good core for modification....." And goes on to explain why the shortcoming for the 194 head cannot be corrected in anyway to offset the shrouding that is caused by its poor chamber design.
I can read the first article fine, but the second one is smaller print and harder to read. I can type out what it says for those that want to know what it says in more detail. But these were articles he had in his catalog that he wrote at one time stating the problems with trying to use the 194 head for performance usage, and they should be avoided.

One thing that should be readily apparent to any astute head porter comparing the 194 head to any of the open chamber heads is that the chamber for the 194 head is designed for an engine that has a bore of only 3.562". But if you don't know anything about the dynamics of how those things interact between head and cylinder, you will blindly follow the countless sheep that have also made the mistake of those before them. Placing it on an engine that has almost a 4.000" bore places the edges of the chamber way too far away from the cylinder bores to breathe freely and greatly shrouds both the intake and exhaust flow. The casting just isn't thick enough to allow it to be corrected when placing it on a bore of this size.
This can often be traced back to the "copy cat" syndrome of, because it works for a small block, it will work on this engine. As many professional engine builders have found, this isn't always true. The reason the closed chamber head swap on the small block works and it doesn't on the 6 cylinder, is because like the open chamber head for the SBC, the closed chamber for the SBC is also designed to be used on a 4.000" bore, thus the smaller chamber does not restrict or shroud the cylinders breathing ability.
And for the 6 cylinder, the open chamber head is always going to be the better choice. All of the top 6 cylinder head porters and engine builders have known this for over 40 years. If anyone tries to sell you the small chamber head swap as being the better choice, they either know that many hotrodders have sipped the "Kool-Aid" and have bought into the "because it works for the SBC" mentality, and are simply taking advantage of you being naive to know any better, or they themselves have sipped the "Kool-Aid" and have no clue either.

I do not know. Engine was built about 20+ years ago.

Brazed lumps were available, but cost too much @ that point in time.

MBHD

I knew the brazed version was, just didn't know about the bolt-ins.

I have use many different cams, but, IIRC, specs were about 236 degrees duration @ .050" .520" lift on a 110 lobe center.
Solid lifter camshaft.

MBHD

I know they had gained more when they stepped away from those weber's. I just wasn't really thinking about how OLD that print was LOL. Besides I dout I'd ever give up my holleys about the only way I'd do that is if went Injection.

CNC,
thanks for posting Kay's articles.

They are a bit out dated as you said, Weber carbs were down on power as compared to running 3 Holley's.

Mike Kirby had told me you can get 194 head to flow good & you do not cut into water jackets as the Hedrick 320 CFM head did.

Mr Hotrod6 has proven the 194 head can work w/the help from Twisted6.

Just because racers from the past did not like the 194 head to race with does not mean a newer generation of racers cannot find new ways to improve a head to work better.

Thanks again

MBHD

Don't get me wrong Larry, Webers were used by many good racers back in the day, and they can still be a good choice if you like that kind of thing. Im partial to Holley's also. I think the Webers were more popular back then because most of all the aftermarket multi-carb intakes were Weber oriented or the primitive Rochester or Stromberg style, but not Holley. And yes, I can see how the Weber would be a better performance choice compared to those carbs. Once guys started making sheetmetal intake and using Holley's more and more, they switched away from the Webers.

Hank you may get that kind of flow out of a 194 head, but it will take the brazed lump treatment and huge port openings to do it. But it still shrouds the cylinders badly because of the chamber being too far away from the cylinder. A flowbench wont show you that.

Many people have proven the 194 head can work! No body is saying they can't. The open chamber head is always going to be better....

You might have gotten 350 HP out of your 250 with the 194 head, but if you had done the same thing to the open chamber head you might have gotten 400 HP.

Wow! that 194 head is worth a good conversation!

I purchased the 194 head mainly because I was switching from an integrated to non integrated head and didn't necessarily trust the quality of some of the online mass cylinder head places. Not many of these heads running around my neck of the woods or at least during the period of time I was looking for one anyway(always seems to work that way)

What I am going to do is run all this info by my buddy who will be doing the work or maybe I will be doing the work in his shop (TBD)and see what his take is on it = really smart dude.

I'll report back what I find out(if anything) and hopefully my little 250 with this 194 head makes some good power when we're done with it.

There are some dyno tests on here that will be worth reading before you spend any money. About 4 years ago both a 250 and 292 were dynod using many different cam, intake/carb, exhaust and cylinder head combos.
Dyno results

My 0-cents. On a mild single carb, shorty headers, daily driver build I'd use the 194 head in a heart beat. I might or might not open it up a bit around the 1.86 intakes. You know the head is a solid one. The small boost in compression will likely give you as much as you'd gain with the extra flow from the other head. They are not all race cars.

VARY GOOD POINT beater Not every Build is a Race Car Or is intended to be one. And as for the Bolt-in Lump Yes is was around 20yrs ago , at the vary least. And yes I know the weber's
are good. I just like my holleys and always have. And they have never let me down. I have been using them If I had to guess well
over 30yrs now.

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.....

can you explain why the size of the bore makes a difference in terms of the intake valve being shrouded? That's the piece I don't understand. The relationship between bore size and the 194 closed chamber head?

That is something that is easier explained with a visual drawing or simulation so you can better visualize what is happening. I'll see if I can draw it up in a CAD model so you can see what is taking place.

But just to give you something to be thinking on while I do that, if you were to place an open chamber head on the tiny bore of the 194 engine, the chamber would overlap and the deck surface and the incoming airflow would hit the top of the block deck before it could even reach into the cylinder, greatly impeding and restricting the flow.

Unless I missed something In all this Who said anything about putting a big chamber head on a 194? And WHY would you even think about it. First off like you said the chamber is Over the Bore DIA. secondly You would lose compression in doing so. It would no dout take you from it's stock 8-1 down to what 7.5-1 maybe even as low as 7-1 That would surely turn that pour OL 194
into a slug for sure. LOL

Yep, you missed it! I was giving a reverse comparison of how the open chamber head would overhang the tiny bore of the 194 block, in the same way, but reverse the tiny chamber designed for the tiny bore of the 194 would be shrouded by the large bore of the 230,250 or 292 because the chamber is too far away from the cylinder bore and severely shrouds the heads breathing. What ever compression you would wind up with in the 194 engine is irrelevant because it wasn't part of the demonstration, just that the large chamber overhangs the small bore and vice versa. Just trying to give moregrip a "grip" on the difference between the two until I get a CAD model drawn for him.

I guess a dueljet and 194 degrees of intake valve duration puts me in the non-race group.

Non-race group here too. I just want it to be strong between the stoplights. As much under the curve as I can get from idle to peak.

In the dyno testing we did a few years back, this puts you right in that range. As I already said, this is a problem that occurs at any and all levels of modification, from bone stock on up and is not a race only issue. So you will be affected by this problem regardless of your intentions.

As I understand it, with the 194 bathtub head, the air coming out of the intake flows out and hits the shrouded wall of the 194 chamber. It then has to turn go down and round the corner to then spread out to fill the cylinder. This reduces the flow and ruins any kind of swirl you might have. While the open head allows the mixture to flow out with minimal redirection to the edge of the cylinder. Is that oversimplifying it or is that basically the problem?

I've been running numbers with the cams I can find an ABDC for, and even with a 4cc flat top piston, zero deck and the thick .040" gasket; you got to have a 64cc chamber for a static CR of 10.0:1 to achieve a dynamic CR of 8.51:1 with a Comp Cams 260 cam to run on premium with good quench. That's a lot of milling on the stock open chamber head. You can achieve the same DCR with the Comp Cams 240 or 252 cams and a 68cc chamber. If you go bigger, the DCR starts dropping off toward the regular unleaded friendly zone. However the Comp Cams measure their ABDC at .006 instead of .050, so they might be a little higher in DCR then the math predicts.

Your only gaining DCR to loose out to inefficiency and lower power output for no reason. You will have a better combo with a lower DCR and the open chamber head. The myth that people can't seem to wrap their head around is that with the 6 cylinder, unlike other engines, the closed chamber head does give a boost in compression yes, but it also results in a HP lose across the entire RPM spectrum compared to same components using the open chamber head.....so what are you gaining?

Yes, you are correct in your understanding of the how and why the 194 head shrouds the engine. So knowing that this is going to occur and you will lose HP and engine efficiency, why do you think still this is a good choice? There is no gain to be had that will be of any advantage at all except that you will now have to run premium gas with no increase in power.

Don't get me wrong, its your money and your build. Just don't be fooled into thinking you are getting a gain when you really aren't.

I didn't say it was a good choice. I was commenting on having to mill down the open chamber head to 64cc to get the advantage of using high octane fuel with the engine parts combo. I'm not even sure if an open head can be milled that far. But yeah, if you have a choice of running premium with a 194 head, or running regular with a milled down down open chamber head, both making the same power with the same cam then you might just want to go with regular gas. But you might even be making less power with the 194 head over the entire rpm range, so using regular gas seems like a better option.

The DCR numbers really show the L6 and open chamber head to be optimized for street builds with cams under 260 advertised duration, but it gets harder and harder to hit that DCR of 8.5:1 without hitting the stock heads limit on milling. I've only got Comp Cams and Crower's cam cards to go off of. Maybe there are some other manufacturers with ABDC that gets you closer with more street/strip profiles.

NOT a problem I'd take them. If they are not cracked and he really wants to part with them.