SO... I'm buying tons of parts to boost my motor and need some head bolts or studs. I already bought ARP main studs, but it seems like someone on ebay is selling a knockoff ARP stud kit for LSs motors. The price difference here is $200, so it is definitely worth looking at (for me, on a budget ).

He says they're rated to 190,000 psi, just like the ARP kit. I'm kind of wondering if there really is that much to a nice bolt that can hold the heads down and if the $270+ price tag justifies the "ARP" monkier stamped into the metal.

Has anyone bought these and if so, does your head stay where its supposed to be?

 

Also, I'm going to be using a MLS head gasket, so I'm not sure if that makes a difference here. I'm probably going to run 12+ lbs of boost.

 

You will always get what you pay for. There is a huge difference "cheap" and "inexpensive". I would use NEITHER for any build. Even in a pinch.

I would do it right the first time so you don't have to pay extra the second time.

FYI, you cannot "knock off" an ARP bolt/stud and sell it for cheap and it be the same quality and/or material.

 

I don't have experiance with them, but i would personally go with what is tried and true. The engine bolts are something i wouldn't skimp out on.

Edit: especially with boost.

 

GET arp its alot more work if u get a leak because of cheap bolts then u still have to go out and buy the ARP anyways plus all the work to fix it

 

Someone care to translate this into english? Thanks

 

I think he said it's cheaper to get the ARP's now, than to get the jank *** studs, and then fix a leaking headgasket that they may cause.

That said, I would have to agree as well. If you want to save some money, consider ARP head bolts instead. It's probably a better route to save money by eliminating parts that may be overkill, rather than buying parts with poor quality.

 

x2 on that.

 

Despite the advice, I went ahead and ordered a set out of curiosity. Here is what the studs look like (next to an ARP main stud). I don't think the difference in the physical size of the nut is based on anything but the fact that there is probably no room for much larger nuts in the heads, or that the width of the nut doesn't matter much.

The threads are 7/16"x20 and it fits a 1/2" 16 point socket. This is the equivalent ARP nut: http://www.summitracing.com/parts/ARP-300-8333/ or mcmaster #90759A450 looks identical to these. Rockwell 34 rating is about 150,000 psi, which is what the ARP material is rated to as well.

The studs have a 7/16" (11mm) grip diameter (compared to the 10mm ARP main studs). Coarse threaded diameter is 7/16"x14, ARP is 10mm.. Fine diameter is 7/16" (11mm) on the knockoff, 10mm on the ARP. This is to be expected, since the main studs and the head studs wouldn't necessarily be the same size. The ARP main studs have a provision for a 9/16" socket whereas the knockoffs are for a 1/2" socket. That is the primary difference.

Thread fit is the same for both, but the ARP nut goes on nicer since ARP seems to coat the bolt with a thicker coating of the smooth black oxide coating. They are also shinier *bling * and have ARP stamped in them *bling bling*.

Honestly, without doing any analysis of the metals, I'd say that the knockoff bolt is probably equivalent in quality to the ARP hardware. If this is able to hold heads down reliably for $70, I don't see why anyone would pay $270 for a set of head bolts. I'll be the guinea pig here and see how they work.

 

I have no experience with that hardware, but where I work had an issue a number of years ago in that we needed a Grade 8 bolt for a specific application. We acquired Grade 8 hardware from a number of vendors, and the first time around, every one of them failed below their rated specification during testing... I don't remember if it was for stretch, shearing, or something else because I wasn't part of the test, but I do recall that they all failed, so we had to find a different source for the hardware. As far as I know, all of the ones that failed were imported.

So... the point that I'm making, is that just because it looks the same as the ARP, doesn't mean it is.

 

I would not out of good conscience use anything of "ebay" brand to build an engine.

I will admit there is a gray area on bolts, because there's several manufacturers that can build a grade 8 or grade whatever stud just like ARP can. There's no magic behind building a strong bolt other than using the correct methods and materials. The problem is, if you don't have any info on the company building these bolts then it's a crap shoot.

 

ARP head studs are about $270.

ARP head bolts, however, are about $100.

 

they won't be so cheap when one twists off down in the block and you can't get it out-i've had to repair a couple of these for customers.Pay me now or may me 3 times as much later-it always seems to work out this way.

 

Dont use them... I know the Manufacture, Dont use them.

 

Why does no one else find it funny the guy is building a motor for 12+#'s of boost and tryin to cut corners on studs. That makes absolutely no ****** sense at all. Thats about as smart as pissin without pulling it out of your pants, LOL.

 

Because some people just have to be different regardless of what people tell them.

 

I would agree that you SHOULD use the arp hardware.

BUT, im also glad in a sense that you are stepping up and trying them out. what the hell right. '

we have all told him our thoughts, but hey, he did say out of shear curiosity he picked them up and is going to be a guinea pig.

 

Satisfying curiosity can get pretty expensive when building an engine. Hopefully, his budget has room for it.

 

^Yep, can get VERY espensive and make that $200 extra for the good hardware a viable expense in the end.

Maybe its just my opinion but if your building a properly built boosted set-up, spending $200 extra on hardware you know will not fail on you shouldnt even be a consideration. Especially when that hardware will be relied on to hold the heads on the engine.

 

http://sdparts.com/details/arp-autom...ts/arp134-3609
http://sdparts.com/details/arp-autom...ts/arp134-3610

I do not see how they are $150 without shipping.