Studs seem to make more sense to me. I'm building with borrowed knowledge and I already have a spanking new set of studs to put together what I have. But I'm hoping to have another motor going together in the next year and just wanted to hear opinions. So how about it? Did Ford go to bolts even though they are inferior because the bean counters said so? Or did they start using bolts because they had decided that studs were suddenly inferior? I imagine that either is fine when properly torqued. I've heard of allignment problems with studs (but maybe crappy aftermerket heads are to blame?). And while I'm dropping questions, what is the difference between an 8ba bolt or stud kit and a 59A kit? They both have 24 studs so what gives? I assume you're matching the studs to the heads and not the block. IE early heads on a late block would require early kit...correct? I'm making an assumption that aftermarket heads that hold more water still retain Ford dimentions at the bolt/stud holes.
I know that a head can get stuck on because of the studs. Bolts are easier.... that is until you break one off in the head..... So, I don't know!
Studs... They protect the threads in the block. Also my personal opionion is that they seal better and hold torque better. Nothing wrong with bolts either but I just like studs better...
When I was building mine I wanted to go with studs because you can use the acorns on them. But everyone who knew about building flatties that I talked to said that aluminum heads will warp even slightly making it very difficult to get the off. Sounded logical to me so I went with the bolts.
Studs as long as you never plan to take the heads off again. Besides the sometimes hassle of getting some aftermarket heads to locate properly you also have the dissimilar metal problem that will bond the heads to the studs. There is no proveable benefit of one over the other in a street engine, I use bolts only as do many experienced builders.
Studs not only because you save the threads in the block but the clamping loads are more accurate with studs because the threads on the stud and the nut are designed to work together, the threads in the block can be damaged, dirty and inaccurate. One point on installing studs is you should not double nut the stud and tighten it into the block. The stud should only be installed finger tight. What happens is when the stud is tightened to much the edge where the last thread comes in contact with the block(where it turns into the shank of the stud) contacts the inacurately machined chamfer at the top of the bolt hole on the block, this causes the the stud to deflect to one side. This is a major reason for having so much trouble getting the heads on and off with studs. Don't get me wrong the castings, factory and aftermarket, are not that accurate and are also responsible for the difficulties with the heads. I believe the factory stopped using studs due to the increased installation time. I have never seen aluminum heads bond to the studs, they will warp and cause interference between them and the disimilar metals between the head and block can cause electrolisis or corrosion. when using aluminum heads you should use hardened washers underneath the nuts or head bolts to keep from damaging the aluminum.
When I did the head on my Plymouth this summer I used grade 8 bolts. Since then I have put close to 1500 miles on the car through different types of climate. I have maintained a consistent amount of torque (70lbs) with no problems as far as leaks. Considering that all I did to the head was shave it down. I still am using the stock cast head. Studs do look good but I think a good grade bolt is a better choice. Especially since down the road I would like to use an aftermarket head.
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