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Does anyone have thoughts or info on increasing the cylinder head studs from 3/8" to 7/16" on an MGA engine?
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Larger head studs in MG engine
- Thread starter Michael Oritt
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racingenglishcars
Darth Vader
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Interesting thought, to do a FEM analysis of the MG head. You can be pretty sure the factory didn't do one. This could give you an idea of the deformation of the head under the compression forces of the bolts.
Larger diameter bolts would still want to give the same compression forces to the head that the factory bolts did or else the head may deform more than it should, and possibly permanently. They would need to be torqued to a lower value (given the same thread pitch). They would then not stretch as much as the standard bolt. Any further stretching of the bolts would be with a higher deformation constant. The bolts can also become loose easier because any un-stretching of the bolts relieves the force very quickly.
Short said, The head bolts hold the head tight by stretching. Larger bolts stretch less and therefore loose their clamping force quicker when slackened. (Slackened due to anything, like for example a permanent deformation of the head)
However, if the standard bolts are susceptable to breaking it would be a good idea.
Larger diameter bolts would still want to give the same compression forces to the head that the factory bolts did or else the head may deform more than it should, and possibly permanently. They would need to be torqued to a lower value (given the same thread pitch). They would then not stretch as much as the standard bolt. Any further stretching of the bolts would be with a higher deformation constant. The bolts can also become loose easier because any un-stretching of the bolts relieves the force very quickly.
Short said, The head bolts hold the head tight by stretching. Larger bolts stretch less and therefore loose their clamping force quicker when slackened. (Slackened due to anything, like for example a permanent deformation of the head)
However, if the standard bolts are susceptable to breaking it would be a good idea.
OP
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Donn--
Thanks for your encouraging reply.
Nevertheless I have relegated this project to the "faggedaboudit" category, along with some of my other concepts such as the hands-free, motor-controlled, voice-activated droplight that will turn off and on and face in the right direction, or the non-disposable toothbrush with tiny, screw-in replaceable bristles.
I have a life to live and races to run--let someone else make the fortune!
Thanks for your encouraging reply.
Nevertheless I have relegated this project to the "faggedaboudit" category, along with some of my other concepts such as the hands-free, motor-controlled, voice-activated droplight that will turn off and on and face in the right direction, or the non-disposable toothbrush with tiny, screw-in replaceable bristles.
I have a life to live and races to run--let someone else make the fortune!
Hap Waldrop
Yoda
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Here's my opinion on this, fabricating something beyond factory specs is like lying, one you tell a lie, you got to tell another one to back up the first one /bcforum/images/%%GRAEMLIN_URL%%/smile.gif So if you got to a larger stud size you'll have to modify the head, more than likely the head gasket as well. I think I would get ARP head studs, if you don't already have them and a good gasket, if you running real high compression ratio look at a Cometic MLS head gasket.
D
Deleted member 3577
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/bcforum/images/%%GRAEMLIN_URL%%/sick.gif /bcforum/images/%%GRAEMLIN_URL%%/lol.gifHap Waldrop said:
Don't you build Prod engines Hap??? /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
Hap Waldrop
Yoda
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Yes, but you know what I mean, pepele just do it alot of the time for heck of doing it. When I bought my FP car, they had a Aeoroquip An hose for the radiator, so you needed to weld a fitting on a stock water pump and the thermo housing menaing you would always need a modified water pump for a spare, simply overkill and over complicating the situaction. kinda like tapping SU float bowls for An hose, why, so you can put a heavier hose and fitting where rubber fuel line will do the same thing, and it what the interior of the Aeroquip hose is anyway, thru the cockpit of the car ok, but form the tee to the carbs, no. Sometime people mdify thing that don't need to be modified, that's the point I was trying to make.
R
RonMacPherson
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Hap, in my experiences, well over 80 percent of all aeroquip lines I've seen in anything other than a full competition vehicle are there for the "oooh" factor.
I think it's guy thing, left over from our teenage years. I was into it a bit myself until I took a really closeup look of one of Dan Gurney's AAR racers back in the 70's. Then I realized that logical, focused engineering is so much nicer than the latest, greatest, shiniest.....
Saw a guy spend several hundred to put -4 aeroquip through his chassis for brake lines, and then moaning and complaining about not having enough funding to run the car. When I mentioned that he would have been able to save a couple hundred on just installing steel tubing in the chassis with the aeroquip going out to the calipers, I was met with the old "deer in the headlights" stare.
I think it's guy thing, left over from our teenage years. I was into it a bit myself until I took a really closeup look of one of Dan Gurney's AAR racers back in the 70's. Then I realized that logical, focused engineering is so much nicer than the latest, greatest, shiniest.....
Saw a guy spend several hundred to put -4 aeroquip through his chassis for brake lines, and then moaning and complaining about not having enough funding to run the car. When I mentioned that he would have been able to save a couple hundred on just installing steel tubing in the chassis with the aeroquip going out to the calipers, I was met with the old "deer in the headlights" stare.
D
Deleted member 3577
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Oh yea...Bling engine bays...
Don't see too many in ITB.
My idea is...Simple is elegant.
Every extra connection is a possible source of future problems as well as any non-standard part.
Plus...I'm crazy about keeping the weight down.
Don't see too many in ITB.
My idea is...Simple is elegant.
Every extra connection is a possible source of future problems as well as any non-standard part.
Plus...I'm crazy about keeping the weight down.
Hap Waldrop
Yoda
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GB1 said:
OK, fuuny story here, back in the early mid 80s when I owned and raced a Huffaker MGB, At the Daytona SCCA national we forgot to burp the radiator and the car got hot enough to alarm me, and I shut if of just before the back straight chicane, the worker waved like mad for me to get out of the car and go up the bank where the lake is at Daytona Speedway, so that's where I sat until the session was over, on the banks of the lake there. Went back to Daytona a few years later, and my crew chief at the time, told me he wanted to show me something he had installed in the trunk for that event , he had zip tied a Popeet pocket fisherman in the trunk, he said if you get stuck over there again, bring us back some fish /bcforum/images/%%GRAEMLIN_URL%%/smile.gif