Not worth the effort IMO
TF's on a 318 ???? Oops, another 318 thread...
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Dale Davies
Well-Known Member
Yup, drag racers test of driving skill. Have a hard time finding reverse let alone negotiating corners at speed.
Dale Davies
Well-Known Member
Everyone seems to subscribe to using the head gasket as the limit to port or relieve to. IMHO this is not exactly correct especially for porting in the combustion chamber. For relieving the bore slightly should be OK for unshrouding, but in the combustion chamber you take it out real close to the gasket which can cause gasket problems. The other issue is the intake mixture hits a small ledge at the top of the bore which will cause some turbulence in a non beneficial manner. I would prefer to Dykem the cylinder head gasket surface and instal the heads on an MT block. Then scribe around the finished bores. This will give a smooth transition from combustion chamber to the cylinder, with only the small area between the difference between the diameter of the gasket fire ring and the bore.
That’s why most off the shelf head gaskets are very large in the bore. LOL
Then there is Cometic for custom sizes.
The head gasket is the limitation of notching the cylinder, or the cylinder head, so that subscription is valid and only to what gasket bore you have on hand or purchase.
Then there is Cometic for custom sizes.
The head gasket is the limitation of notching the cylinder, or the cylinder head, so that subscription is valid and only to what gasket bore you have on hand or purchase.
Dave_J
Well-Known Member
Maybe not to you but on a 273 or 318 its not too bad and not a hard job. Maybe 2 hours with a carbide.
A set of 360's 1.88" intakes in a super ported 273 closed chamber head, a 292 DC cam, Weiand Stelth Intake and a set of 340 A body exhuast manifolds made a 1966 Dart Wagon with a 0.060 over 318 a sleeper.
You work with what you have or can afford.
I would never grind the head chamber out to the gasket bore, close but not to it. You are right about problems blowing the fire ring out as the head does move a slight amount sometimes..... Harmonic distortion.....
But to go almost to the fire ring on the block side is not as bad. And only for a small section of the diameter.
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Dale Davies
Well-Known Member
True
True story. For a race only engine you can chance things to their limits, but a mostly street engine is best with a little on the table for a safety factor.
dirty white boy
50 yr old Juvenal delinquent
id bet my azz a 2.02 valve comes closer to 4.0 cylinder wall with a 23 degree head than it ever would in a 3.91 cylinder with 18 degree heads but you dont see chevy guys notching the cylinder bores,..shrouding is more of a myth than a reality!! alot of 23 degree chivvys use a 2.05 and 2.08 valves with no issues! it just ant needed in my opinion!
B3422w5
Well-Known Member
the guy/shop that just did my 418 with eddie heads. He showed me how shrouded the valve is even at 4.08 bore.
Said there was 20 horse in fixing it.
He is VERY smart.. won enginemasters competition with a small block Mopar.. I will take his word for it being an issue.. and a 318 has a much smaller bore
dirty white boy
50 yr old Juvenal delinquent
yall trying to wrench the last 20 hp outta im guessing a race motor,enginmasters and all,....ant we talking street motors here??? .090 ant that much, a good thumb nail thickness dayummmm!
SS Lancer
Well-Known Member
Thats right help a fellow out etc !
Save 340s for resto builds
Build the 318s and 360s
You would do this for a street engine? I don’t think you would ever feel the difference. Not worth the “STREET” effort and that’s what we’re talking about here right?
Race engine… sure, knock yourself out.
Agreed, not on the street or even mile strip cars. If it was a race only deal chasing the money on a big scale, sure!
Did you “Fix it” or just run it?
I can certainly see that type of power gain and better. Build dependent of course.
Dale Davies
Well-Known Member
Well now dirty boy, you also do not see Chubby guys stuffing 2.05 or 2.08 valves in a 305 engine. Their just is no room. Now could they notch the bore for valve clearance and shrouding? Of course.
Being as you are a "shrouding doubter" mebe you is needin to get copies of David Visard's books; How to Port and Flow Test Cylinder Heads and How to Build Horse Power. It may be an idea to also watch some of his PowerTec videos. You may just learn sumat before ignorance hurts you.
Love David’s videos and books.
But you seem rather insulting with your twisted words trying to mimic a southern accent.
But you seem rather insulting with your twisted words trying to mimic a southern accent.
dirty white boy
50 yr old Juvenal delinquent
there you go posting enginemasters/max effert tech in a street/grocery getter build thread again!! and you wanta suggest who might get hurt by ignorance, bless ya hart mann...
I can only like or agree but not both…. Darn shame.
Find 20hp in 5 places and all of a sudden you found yourself 100hp,or 10hp in 10places is also 100 total or why not an easy 5 hp in 20places?
The difference adds up quite quick when you start paying attention to stuff and is the reason why some poeple are engine builders while others are just (in best case scenarios) assemblers.
If we are going to ignore all the small stuff just because its not a raceengine we start to leave a whole lot on the table,a whole lot of "free" power,power that wont screw up your drivability,fuelconsumption or lifespan of the eninge.
An engine with a ton of very nice and expensive parts on it can be beat regarding power,durability,fuelmilage,performance and drivablitily by something built from much "simpler" parts if the builder has payed attention.
Not saying everyone has to pul out every trick in the book,sometime something simple will do just fine and sometimes one wants to assemble a bunch of very fine parts ignoring the fine details and the owner will be just happy about the result but the whole "ohh its just a streetengine and not a raceengine" is not the best argument for it looking at a much bigger picture.
dirty white boy
50 yr old Juvenal delinquent
i agree with most of this but i disagree theres 20 hp in notching a cylinder bore half a fingernail bigger less than .300 below deck to stay above the ring! that lil bit would be un noticeable on a dyno and mean dittly chit above .300 valve lift!! hell then again might help the grocery gitter a lil bit under the curve....just my humble whitetrash opinion....
Dale Davies
Well-Known Member
Actually dirty white boy, I try to see all sides. If you have been watching, I just had a difference of opinion with yellowrose over big bore. I was trying to explain there are other interests beside racing, and that even in racing there are things to consider with respect to bore and stroke for different tracks or applications. My interest is more toward strong running street engines that run cleanly. The engine masters is supposed to be a showcase of engine builders talents, supposedly aimed at street use. I doubt anyone would argue their engines are more race oriented with 0.8" valve lift and 2:1 rocker ratios.
Now David Visard has built many race winning engines for multiple series, and worked with F1 and Cup Car teams. So he definately knows the bottomless money pit race technology. Ignore that bit and read his books or watch the videos. If you keep an open mind, you can pick up usefull information from different sources. Much of this can be applied relatively inexpensively for street use.
Have a good day.
B3422w5
Well-Known Member
fixed it. And to be clear, this involved clearanceing the bowls to unshroud the intake valves on eddy heads
Cool man. This is the mill you reported on a little while ago at the track?
B3422w5
Well-Known Member
yes. The heads have very minor porting, but my guy thought doing this work was worthwhile cost to benefit
No argument there.
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