Nail head and tulip head?

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Valvebounce

Valvebounce

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Would it hurt any to run a Nail head ex valve, with a tulip head inlet valve? I'm slapping together an engine using parts aquired cheaply/what I've got laying around. And thems the bits I have. The main difference I see is the nail head valve will fill up a fraction more of the chamber volume. If there is some other cardinal no-no in running this combo, I could scallop out the face of the valve head on the lathe. (I did this to help lower the CR on my little supercharged pushrod inline four bout a year back)
 
Use the nail head valve.It will reduce the chamber volume and if the valve margin is thick it will increase air flow,but use the same size valve,don,t go bigger,mrmopartech
 
This is my dilema. It's a 318 head. Someone has already fitted 1.88 inlets to them. All my 1.88 valves are tulip. The 1.5 ex valves are all sunken. The 1.6 ex valves I have to replace them are nail head. Will running the two different kinds together create a paradox that will destroy the space-time continuim? Or will It be fine?
 
I would replace them all to make the heads better,and safer.With the nail head the chamber volume goes down and the compression goes up,and if the margin is thick like I said,the flow will be better.So its a win/win situation,as long as a good 3 angle valve job is done and some bowl work and match and porting,don,t do any runner enlarging,mrmopartech
 
Have hardened seats installed, to raise the sunken. And anybody that does a valve job, not 3 way- it ain't a real valve job. Impossible to do a valve job without 3 stones.
 
green1 said:
Have hardened seats installed, to raise the sunken. And anybody that does a valve job, not 3 way- it ain't a real valve job. Impossible to do a valve job without 3 stones.
Click to expand...

Its almost impossible to get a valve job today using 3 stones, they are all Serdi if they are worth the time (But I get your point) ;-)
 
A three angle job goes without saying. Althtough whoever the amature was that fitted the 1.88's only had a one angle job done. They also never bothered to blend the bowls either. So I doubt whether or not they would have flowed any more than the standard valve would have. I would like to use nail heads for the intakes, but cost is a factor. (Using valves I have, verses using valves I'd have to buy)

Stuff can be had quite cheaply in your part of the world, but I have to figure freight charges and currency conversion charges into the equation.
 
Yes, you can run tulip and/or nailhead in either position. In general, tuliped intakes will flow better at low and mid lifts with a stock port. If it was me, I'd have them do a back cut on them too. That yeilds nothing but good through the entire lift cycle. The exh is not as critical as the piston forces out the gasses, especially ina street car with full exhaust. So use whatever is available.
I'll add - I have no more interest in stone valve jobs than I would in running a Carter WCFB carb on an engine. There is much better available very cost effectively now. If a guy's using stones and doing it professionally, find another shop.
 
Many thanks for the advise guys.
I need to get my heads done so I can see where Things will be at with the rest of the motor. The heads have been shaved in the past, so I want to fit the new valves, and measure the chamber volumes before having the block decked.
 
I'll add - I have no more interest in stone valve jobs than I would in running a Carter WCFB carb on an engine.
Click to expand...
Thats Because yours is much faster!!!!

Its kinda like dial up internet it will do any thing the faster ones will............But once you brake a way form dial up. you would rather not have internet then to go back to dial up!!!!!

I thing you can do as good of job with stone as anything else......it just take a lot of pations and time. Of couse it's one sided, as i have never used anything else.:scratch: LOL
 
It takes a tremendous amount of experience to do a stone job well, and it uses a lot of stone to do it properly and this is not meant as a personal cut on whoever uses them. That's actually how I learned to do valve jobs. That was in the 80s. Time and technology marches on and a tapered pilot will never be as good in terms of concentricity, accuracy, or repeatability as a properly sized straight pilot, floating head, and multiple angle cutter. In my garage here is a Petersen TCM-25. Again, old school in terms of valve/seat equipment (It's also from the 80s), but it will do way better than a set of tapered pilots and the most careful stone grinder. I'm not saying they won't run with a stone valve job or that anyone personally sucks at it. I'm saying that comparing results to results, even if the stone setup is done as perfectly as it can get, there is MUCH better, for similar money, no way to get them as good as the modern Serdi or Sunnen equipment. The shop I use has the Serdi. My TCM is for sale.
I'll add for years I ran dial up, because of my home location (waaaay in the sticks). I'm not spoiled. I'm a realist with high expectations...lol
 
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