Boost boy - ARP head studs q's

[CA19DET]

i asked the new local ARP dealer for the head studs that you posted were the correct ones:

ATP 5.060-1LB (10 peices)APN 12-1 (10 peices)

well ARP tells him that those are not ARP part numbers, they say that their part numbers are 6 digits.

now i was "told" this and have not spoken to ARP directly, are you sure these are the correct numbers and you have used them?

please help me clear this up

[CA19DET]

i'm thjinking maybe he is asking for that part number in reference to teh CA18 and they are telling him it is wrong or a different number, but i already got the wrong bolts from them already and i want to clear this all up...

[float_6969]

I thought you had to modify the head/bolt to make them work?

[ca18det_boy]

ARP should actually have a part # listing. Off the top of my head I don't know what it is, however I do know that they have them. I'll do some checking and get back with everyone.

[CA19DET]

they have all sorts of part numbers for the CA18 head bolts, and they sent me the wrong ones already, so i just wanted to clear this all up, and hopefully Boost_boy will soon

[float_6969]

Is there something wrong with the stock units or is this just a precaution?

[boost_boy]

Part #s are APN12-1 (10pcs)(nuts), ATP 5.060-1 LB (bolts) (10pcs), APN-58 (washers) (10pcs). Revised.............

[CA19DET]

thanks i'll give ema shot

[boost_boy]

Quote »Is there something wrong with the stock units or is this just a precaution?[/quote] Just a precaution! Big power needs more clamping force on the head and block. The stock bolts would work, but would not be reuseable once you take them loose.

[diamondstar36]

ARPs or some type of stronger head bolt are really needed to prevent the cylinder head from "lifting" because of pressure in the cylinders.

[float_6969]

Well I realize that, but at what horsepower levels does this become a concern?

[diamondstar36]

About the time the stock headgasket goes. So around 300whp I guess. It probably becomes an issue before that though.

[Nismo1182]

Part #s are APN12-1 (10pcs)(nuts), ATP 5.060-1 LB (bolts) (10pcs), APN-58 (washers) (10pcs). Revised.............

So these bolts are a totally diffrent style than the stock ones?

Im guessing these go on the block first, then you place the head on the block, then the washers and nuts?

[boost_boy]

Quote »So around 300whp I guess.[/quote] If you're tuning with the little magic/pretty blue screen box or others, this could be a possibility. I'm at 400+ with my woman's car and it hasn't even attempted to buckle on a factory stock set-up minus the HKS camshafts, SDS standalone and a set of MSD 50lb/hr squirters. It's all about the fuel and tuning "Point Blank". And yes to all your questions, Kevin...........

[float_6969]

Dee, that is how I feel about it. I don't think I'm going to mess with mine. I'm just going to buy a new stock set.