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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Head studs and gasket suggestions

So, with a new headgasket due, I plan on getting a new set of hardened studs. Any suggestions?
and, while we're at it, the ongoing question of the best headgasket...

Don
don g

I dont think you can go wrong with Payen DK 450, and being that the engine is stock Id say just the grade 8 standard hardware,,, Id check with John Mangles, he can get you the correct stuff, no need for the ARP stuff.

Can you post some pics of your head gasket? Id like to see where it failed

Prop
Prop

thanks, Prop.
yes, i'll post pics. Hopefully can get started on it this weekend.
don g

The ARP bolts have proven to be difficult to work with. I had two gasket failures following a rebuild, apparently due to over-torquing.

Torque is lower, with ARP bolts, especially when using their moly lube on the threads. So if you torque ARP bolts to Haynes specs, this apparently is too much even for a Payen gasket. The Payen gasket seems even more sensitive to over-torquing than a paper type.

If I had it to do over, I would probably have reused the original studs and nuts.
Glenn Mallory

and i had 3 "original" studs break in a row
so i would go with competition spec studs (not necsicairly arp)
if you just folow the instructions given with the arp studs they work perfectly
Onno Könemann

Probably a rare example where quantity might work better than quality though both is best of all.

Convert the head and block from 9 studs to 11. Use ARP studs.
Daniel Thirteen-Twelve

I have just done the same job on a 67 Sprite and replaced the studs with a std set and a BK450 head gasket from Mini Spares after suffering a failure only after a year.

I decided this as the car is std and after 300miles it is running better then it has done in the past with a better oil pressure.

I can only put it down to replacing the studs

Hope that Helps
Shaun
Shaun

Yikes. my headgasket failed after 3 years. i figure its from the original studs. was going with the good ones- ARP. now it sounds like they could be a problem. now i'm not sure what to do!
don g

Prop,
is this the gasket you're talking about?

http://www.7ent.com/detail.cfm?pageid=50
don g

Hey Don,

Thats the new Head gasket I got.

do a test mock up putting the gasket on the deck and see if there is any movemnet sliding it around with the studs in place (w/o head) this is something Im just becoming aware of apperantly the Head gasket is "walking around" because there is no pins or close fitting studs

willy from OZ suggested using aluminum tape on the 2 closest fitting studs to help remove the slop on the HG holes vs the studs and use VHT coppercoat gasket sealer in spray form;

the 1st stud is on the exh side of piston #1 the 2nd close fitting stud is between piston 3/4 on the dissy side... those are the 2 studs you wrap on the studs to fill the slop from the stud to head gasket.

hope that helps

Prop...look close the gasket says front and (top... dissy side of gasket mid way)

Prop

don
don't listen to prop
ARP is the way to go if you have the butget

prop has all sorts of problems not norrmaly occuring on A-series engine's
he is a verry special boy ;)
Onno Könemann

Don-

I agree with Onno. Go with AWRP if you have the budget. The do not require less torque! Only if you use their lube. I routinely take our race engine to 50 with no evidence of head gasket failure due to over- torquing. Just follow the instructions and don't listen to anything else! Be sure you do it in stages. Usually increments of 10 ft-lbs to the spec.

HTH
Tim Michnay

got the arp's ordered...
don g

Hmmm,

I wasnt suggesting that he should not get ARP, after all thats what Im using, but for Dons car which is pure stock... I dont think they are nessariy! But yes ARP is the gold standard in fasteners and carry a hefty gold standard price tag as well around $180 vs $35 IIRC, On a pure stock engine I just dont think he will notice a differance.

just make sure you wash the hardware in acetone before you install and torque to ARP spec not haynes spec


Don did you over torque the head studs, I wasnt aware of that?


prop
Prop

prop has all sorts of problems not norrmaly occuring on A-series engine's
he is a verry special boy ;)

LOL... Nothing special about me, but thank you for the compliment.

My problem is the only part of the engine thats still orginal or un-modified in some way is the vacume hose from the dissy to the front carb, everything else has been upgraded or massaged in some way, so getting everything to work with each other is a real pain, sorta goes back to Aries thinking

At what point during the modification process does an A-series IS no longer an A-series?

Prop
Prop

"Don did you over torque the head studs, I wasnt aware of that?"

no, i didnt over tighten them... i dont think. lol!
don g

<On a pure stock engine I just dont think he will notice a differance.>

No, he won't notice a difference. ARP are more durable and can be re-used. In the long run they can be less expensive. The stock sutds and nuts will tend too deteriorate when used over and will not be as reliable. I do hope you ordered the nuts too. It isn't neccesary to use their lube either. Only if you want to. The choice is yours. The only reason for the lower torque when using the ARP lube is that it will give the same amount of clamping force due to the difference in the friction between the nut and stud.
Tim Michnay

thanks, Tim. Yes, got the nuts too. the kit cost about 180.00.
don g

Deb Evans did quite a good writeup a little bit ago about torque, clamping force, etc. If you can find it, it's a good read for this sort of thing.
Tim Michnay

Prop - plenty of people have very non standard engines without anywhere near your level of self imposed complications - any yet you insist on telling everyone else what they should be doing.

What Revs and what CR will your engine be running....what power were you aiming for ? why did you feel the need for arp fasteners
Dean Smith ('73 RWA)

8k sustained RPM, 10.25 CR, 120hp.... Yeah I doulbt the ARP will hold up ither under those conditions, I may have to have a custom set of studs made.

My goal has never changed... drive 160 mph at boonville salt flats before im 60 in an mg midget

prop
Prop

>>>>>Prop - plenty of people have very non standard engines without anywhere near your level of self imposed complications - <<<<<<<<<

Thats vary true, I have bit off way more then my ability and skill level and I wish I had stayed with a stock engine build.

AGIAN....its just my opinion!

Dons engine is "standard" its pure stock with no performance upgrades Plus I know Don perfers to use his hard earned cash to restore his MGC rather then his MG midget... both vary nice cars, with Dons midget being 39 years old, and a pure stock engine I just think the orginal new stock stud hardware will last another 35 years with no issue, Im glad don got the ARP, it will serve him well

>>>>>any yet you insist on telling everyone else what they should be doing.<<<<

If don knows whats good for him, then by god Don will do what I tell him to do... In st. louis my word is law, dis-obediance wont be tolerated!

Prop
Prop

Lost track of when you're being serious and when you're going for sarcasm. Its all just pointless noise these days.

But your build simply does not add up and I think you're probably putting people off rebuilding their own engines when it can and should be a straightforward and enjoyable diy job. The archives are certainly now full of complete rubbish.
Dean Smith ('73 RWA)

opps forgot the "L.O.L."

Prop
Prop

Dean in all seriousness...

Im vary aware the effect my engine build has had and may will have. and its my hope that people down the road will know that im an amuture building a high end race engine and wont be discouraged but serve as an example to uild with in there ability level and to grow in ability from one engine to the next

It was a vary tough "Comming to Jesus" moment a couple months ago that I have gone well beyound my capabilitys, If there is anything to be learned from my experiace, its to start off low, slow and build up as your skills deevolop, due to my Arrogence, love for self gandure and vanity I have screwed up! Im building an engine that I should not have attepted for at least 10 engine builds from now, needless to say the learning curve has been steep and brutel at times. My biggest mistake among many was underestimating the difficulty involved in building a a full hard core race engine, its daunting to say the least, The more modification the more those modification compond many steps down the build road.

The only way to discribe it is if your learning to fly for the 1st time. In a ceesna 150 trainer, you can make all kinds of mistakes and wing it with no issue, but if your flying F-16 at mock 3 you better be flying your A-game with lots of traning and air time.

Essential thats what Im doing, im getting my beginner piolts lic. at full throttle of an F-16 combat plane, by simple reading a book and magizine articals and my own grit and can-do anything i dream of attitude ... At this point, its just pure gut thats getting me thur.

Prop
Prop

<8k sustained RPM, 10.25 CR, 120hp>
Not to burst your bubble Prop, but that isn't really that high end. The 8k will depend a lot on your valve springs, whether or not they will float. Have you had your engine on a dyno? If not, there's no way you can know how much HP your engine will be putting out. 120 sounds pretty high for those specs. A lot also depends on your cam. To give you an idea of a high end race engine, here's the spec from the our bugeye race engine:

14:1 CR
8k redline, but we only like to take it to about 7600 for increased longevity.
.040 oversize bore
APT VP5SP cam was a Kent 310 SP when we got the car, but it developed a bad lobe
No idea what the HP is sincec it's never been on a dyno.

Also, due to the cam, won't idle under about 2500 and also shouldn't. Definitely not driveable on the street.

Hope that you get yours going this weekend. The weather has been great up this way for getting out and enjoying a drive! Summer will be going fast...
Tim Michnay

I'm a bit biased here, but for the time and money that Prop has spent, he could have built a solid stock motor and bolted on a Moss supercharger. Then he could be out driving with a pretty peppy and worry free engine.

If someone tells me they want a "hot" A-series engine for the street I strongly endorse the supercharger route. I'm sure I do not have as much time invested in my engine as Prop, and probably not much more money. And... I'd put a healthy wager that my car would make as much hp as Props AND be more streetable.

But... I took the easy route and bought a kit where someone else had done all the engineering. Then I went to an engine builder that specializes in forced induction and picked his brain and took that information to my machine shop. So... even though I put the stuff together, the ideas all came from other people.

When Prop is finished he will have an engine that is uniquely his and he will most likely have a greater sense of satisfaction from the job.

But... while he is busy in the garage I'm out trouncing TR6's in drag races and leaving the heavy Healey's behind in the curves.
Trevor Jessie

The 8k susained is dreaming I know now but orginally I really thought that was do-able...yyyeeee Not so much now! But with everything that can be lightened, balanced, or replaced with better quality parts, its gotta be able to hold 7K. granted I dont plan to drive at a sustained 7k, but will be nice to know I can. This is the area I put a bulk of the work, time and money at...If its not fast, it will certianly be indestructable and smooth running, the only thing I regret was not being able to get a set of cerrilo connecting rods (not for a lack of trying), but I could never swing the price tag. So the cooper 521s along with the EN40B crankshaft will have to suffice

the 120hp Is probable a really "good hope so", But I cant imagine being less the 100 hp. certianly double over stock...Next spring I hope to put it on a dyno, theres a rolling road at lake ozark, not a BMC, but they do alot of differant cars, so at least Ill have an idea of what it can do.

Treavor has no idea how much Ive re-thought that idea of a super charger on a good tight stock build... it really does make good scence, I looked into it orginally and abondoned the thought, as to complex, what was I thinking...LOL

Prop
Prop

Prop,
I don't know where you live but if I ever was traveling in your area I would love to meet you and see the "Prop-rod". I think it would be the highlight of the trip.
tomshobby

Tim,

Ill be at spridget 50 at road america in elkheart WI ... june 2011 are you going to be there?

http://www.sprite-midgetclub.org/

prop...In jefferson city Mo.
Prop

I am working to get my Midget running in time to be there.

My brother and I took my TR6 for a drive through Missouri, Kansas, Oklahoma, and Arkansas last summer. Too bad I did not know about you then, could have stopped by.
tomshobby

Sure hope to be there. It's only about a 2 hour drive from my house. A lot may depend upon work (or lack of it!). Hope you can get your car running good by then so we can see it up here!
Tim Michnay

So which is the better place to stay ...

The victoian village or the siebkens resort

prop
Prop

This thread was discussed between 21/05/2010 and 31/05/2010

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