Craycraft was offering a head stud kit, I think made by ARP, a while back.

Haven't heard much talk about it.

Check out 14mins.com.

 

THey are probably bolts for another application. It would be nice too know the application...no doubt the bolts would be much cheaper. Does anyone know the exact dimensions of the bolts....should'nt be hard too run something down...[img]i/expressions/face-icon-small-cool.gif[/img].

 

out i did say in post that they did stretch a little. but as long as they are not over torqued then they will be ok in most of our applications for the raptor. when i talk about problems on here i talk about the particular engine in the question. in this case the raptor engine and its head and cylinder bolts. the the left side cylinder bolts on the raptor always are lose when disassembly on the engines. that reason is why some people use way too much lock tite on the bolts and then use a tap to clean the threads which isnt good.

the cylinder bolts are 2 each of10 x 1.25mm and 108.5mm long from end of bolt to the bottom of the head of bolt
2 each of10 x 1.25mm and 115mm long from end of bolt to the bottom of the head of bolt

the head bolts are as follows:

4 each of 9 x 1.25mm and 108.5mm long same measure meant as above
2 each of 9 x 1.25mm and 40mm long

 

I just order new ones to make me feel better.[img]i/expressions/face-icon-small-smile.gif[/img]

 

donr forget about those stretched timing chains..

 

my new head bolts and cylinder bolts will be here soon and i will let you know if they have streched at all. which i doubt because of the amount of torque we are using in the raptors application isnt that high. a grade 8 bolt in a 10 x 1.25 can go up to a torque of 125foot pounds, and has a failure of 142ft lbs the book only says to torque to 30ft lbs.

 

He didn't get enough intrest in them to have a batch made. Because these would have been custom made he needed to have a lot of them made up to keep the price down. They were not from another application and he was having a stud kit made not a bolt kit.

 

well new cylinder bolts arrived today and the difference was only .1mm which is around .004 or .005" so they didnt stetch that much at all. my cylinder bolts are torqued to 33ft lbs and the head bolts i get a final torque of 35ft lbs.

 

The manufacturing tolerences are probly +/- 2mm how many torque sequences are you doing? are you using the factory torqe pattern?
Hers a pic of the factory pattern click the area pointed out are the long skinnys along the chain/cam gear I have bolts I put in and pull down when I torque the head bolts . this prevents soft shoe " warping term " and make sure you lubricate the bolts lightly .

 

i torque mine over the factory specs. 33 and 35ft lbs
i use a thread lube on them .
i have heli coils in my cases now and the head will have have them after 3-4 torque sessions