all Aluminum 2point8 prototype race engine???

Shaun41178(2) · Post by **Shaun41178(2)** » Sun Jun 12, 2005 2:32 pm

Timeserts work in a similar way like a helicoil would.

Helicoils dont' pull out do they?

Sort of the same principle.

If I were you, I would get the timeserts, and then buy ARP head studs.

Using bolts the first time on the block was probably not a good idea. When using aluminum parts like blocks or heads or intakes, its always best to use studs but of course that is not always the most economical. Studs keep the threads from getting torn up.

The Dark Side of Will · Mon Jun 13, 2005 1:09 pm

p8ntman442 wrote:$$$$$OUCH$$$$$ did I mention the new baby on the way?

IF the old threads pulled out what will keep thetime sert from pulling out?

What condition were the old threads in? Heat cycled... corroded... fatigued... stress fractured from repeated R&Ring of cylinder heads...

installing an insert cuts virgin threads, which are then used only once when the insert is installed.

Also, the timesert has a larger OD than the bolt, which means that it pulls on a larger chunk of the block than the bolt did and is thus stronger.

p8ntman442 · Post by **p8ntman442** » Tue Jun 14, 2005 12:15 pm

Good point, I did get 115 nm on the main bearing caps. I Got the number of a local time sert distributor to contact after work. Baby showers this weekend so hopefully I can atleast have the parts ready for next weekend to do it.

The Dark Side of Will · Wed Jun 15, 2005 6:31 pm

Shaun41178(2) wrote:Timeserts work in a similar way like a helicoil would.

Helicoils dont' pull out do they?

Sort of the same principle.

If I were you, I would get the timeserts, and then buy ARP head studs.

Using bolts the first time on the block was probably not a good idea. When using aluminum parts like blocks or heads or intakes, its always best to use studs but of course that is not always the most economical. Studs keep the threads from getting torn up.

Different things hold helicoils and times serts in place. Unscrewing a bolt from a helicoil tries to expand the helicoil against the inside of the hole, holding it in place. Time serts hold by being cold formed in the hole during installation.

p8ntman442 · Post by **p8ntman442** » Thu Jun 16, 2005 12:08 pm

Well I removed one head yeasterday and not much damage at all. The threads on the head bolt that was really bad actually threaded off the bolt when it was out, so maybee it was a HELICOIL, i dont think normal threads would do that. The kit for the timeserts for M11 X 1.5 is 125 bucks plus 13 more inserts at whatever they cost. 5 come with the kit and I figure 2 extras just in case. I Ran a die over the old bolts and that size seems to be correct. Anyone think otherwise?

The Dark Side of Will · Fri Jun 17, 2005 9:39 am

Dam GM and those 11mm head bolts...

Doesn't sound like you're missing anything.

p8ntman442 · Post by **p8ntman442** » Fri Jun 24, 2005 12:15 pm

Ok ive been digging and obviously 11mm bolts arnt made, not here in the us atleast. So opinions are welcome.

what I think I should do is buy arp studs for my block insert them with loctite into the existing threads. (the old head bolts only went .8" into the 2.3" hole leaving a lil over an inch of threads). Then Install the heads over the studs and torque to 85 ft lbs (fiero 2.8 specs are higher than I need for this motor, smaller valves make less power) my manual for older 2.8's show anywhere from 75-95 depending on application. If they pull out, I still ahve it out of the car and can get the time sert kit and use the northstar inserts (longer) to fix the holes.
cost: arp studs $82 plus $150 time sert kit with n* inserts.

problem: arp studs arnt long enough or threaded far enough.

I could also get the timesert kit and use the n* inserts with the long head bolts in the short holes and longer possibly n* bolts in the longer holes.

anyone ***cough*** will ***cough*** know the length of n* head bolts? I need about 6" (no jokes guys)

Shaun41178(2) · Post by **Shaun41178(2)** » Fri Jun 24, 2005 12:59 pm

Huh I have ARP head studs in my al block(head rack) for a mock up and I screwed them in and was still able to get the heads on there with the threads still sticking out to put the nut on.

Are you saying your head bolt threads are deeper then what a stock block is?

Do you have the ARP head stud kit yet?

p8ntman442 · Post by **p8ntman442** » Mon Jun 27, 2005 12:03 pm

I was going by the picture of the arp studs on summit. My thread holes are 2.5" deep, so Id like to get atleast 2" of threads in there. If I get the time sert kit with 12 mm sleeves, I could go with grade 8 12 mm bolts that I chop the heads off to make my own studs. That way im pulling straight up not twisting on the time serts. 12mm is pretty big but will fit in the holes in my heads, except at the very top where there is some material left that wasnt removed after the casting.

Kohburn · Post by **Kohburn** » Mon Jun 27, 2005 12:26 pm

p8ntman442 wrote:I was going by the picture of the arp studs on summit. My thread holes are 2.5" deep, so Id like to get atleast 2" of threads in there. If I get the time sert kit with 12 mm sleeves, I could go with grade 8 12 mm bolts that I chop the heads off to make my own studs. That way im pulling straight up not twisting on the time serts. 12mm is pretty big but will fit in the holes in my heads, except at the very top where there is some material left that wasnt removed after the casting.

going up to 12mm will change your torque specs - but will make it easier to get replacement bolts

Shaun41178(2) · Post by **Shaun41178(2)** » Mon Jun 27, 2005 5:48 pm

The ARP studs will thread in about an inch and a half. I am just eyeyballing them but thts how long the threads are that go into the block.

The Dark Side of Will · Mon Jun 27, 2005 11:00 pm

p8ntman442 wrote:I was going by the picture of the arp studs on summit. My thread holes are 2.5" deep, so Id like to get atleast 2" of threads in there. If I get the time sert kit with 12 mm sleeves, I could go with grade 8 12 mm bolts that I chop the heads off to make my own studs. That way im pulling straight up not twisting on the time serts. 12mm is pretty big but will fit in the holes in my heads, except at the very top where there is some material left that wasnt removed after the casting.

Anyone keep up with USCC?
Remember that MkII MR2 that had a 3SGTE built to turn 10,000 RPM (built by Trueleo, the same shop that makes the high flow 2point8 intakes)? The SCC writers thought it was the most amazing thing in the world that the guy drilled the block and head out for bigger head bolts so that he could run crazy boost and insane RPM... Here you are doing that very same thing just to make it easier to get bolts...
Chevy guys go to bigger head bolts on occasion as well. Been doing it for years, even.

Indy · Post by **Indy** » Tue Jun 28, 2005 1:12 am

The Dark Side of Will wrote:
Anyone keep up with USCC?
Remember that MkII MR2 that had a 3SGTE built to turn 10,000 RPM (built by Trueleo, the same shop that makes the high flow 2point8 intakes)? The SCC writers thought it was the most amazing thing in the world that the guy drilled the block and head out for bigger head bolts so that he could run crazy boost and insane RPM... Here you are doing that very same thing just to make it easier to get bolts...
Chevy guys go to bigger head bolts on occasion as well. Been doing it for years, even.

As a tidbit of info, upgrading to 1/2" head bolts was part of the standard Super Duty prep.

p8ntman442, you might want to think about having ARP just make you a set of bolts. One thing that I would be concerned about would be that modifying the bolts could affect the heat treat and possibly weaken the part. Speculation on my part, but maybe something to consider? It probably wouldn't be catastrophic failure if a stud failed, but that's never a fun thing...

Nate

The Dark Side of Will · Tue Jun 28, 2005 6:17 am

Indy wrote:As a tidbit of info, upgrading to 1/2" head bolts was part of the standard Super Duty prep.

That's probably what I was thinking of... I must have read it in your post about your engine.

p8ntman442 · Post by **p8ntman442** » Tue Jun 28, 2005 12:22 pm

Ok, I got some refference books here at work and Im gonna do some research into the diameter of threads and the holes they are made in, so I can figure out what size bolts will go in good, im not sure 12 mm threads in a hole already tapped for 11 will hold up at all. Testing on a chunk of aluminum will be done first. I doubt cutting the head off a grade 10.9 12mm bolt will drop its tensile strength more than 10,000 psi

besides im running less than stock 2.8 hp for now so im not too worried about sending the heads into the stratosphere.

p8ntman442 · Post by **p8ntman442** » Tue Jun 28, 2005 12:24 pm

Indy wrote: Anyone keep up with USCC?.

p8ntman442, you might want to think about having ARP just make you a set of bolts.

If I knew for sure 11mm would hold, Id do just that, but I dont know. I cant even get 11mm threaded rod to cut to length in any strength to test it with.
Nate

Kohburn · Post by **Kohburn** » Tue Jun 28, 2005 1:56 pm

p8ntman442 wrote:Ok, I got some refference books here at work and Im gonna do some research into the diameter of threads and the holes they are made in, so I can figure out what size bolts will go in good, im not sure 12 mm threads in a hole already tapped for 11 will hold up at all. Testing on a chunk of aluminum will be done first. I doubt cutting the head off a grade 10.9 12mm bolt will drop its tensile strength more than 10,000 psi besides im running less than stock Boat Anchor hp for now so im not too worried about sending the heads into the stratosphere.

metric thread pitch is a handy thing - if an 11 and a 12 have the same thread pitch you can run a tap right into the 11 and open it up

The Dark Side of Will · Tue Jun 28, 2005 10:01 pm

Tap drill = nominal diameter - pitch

12 x 1.75... tap drill = 10.25

p8ntman442 · Post by **p8ntman442** » Wed Jun 29, 2005 12:26 pm

1/2 inch head bolts anyone????? gonna take a look at the feasability tomorrow.

Kohburn · Post by **Kohburn** » Wed Jun 29, 2005 1:12 pm

The Dark Side of Will wrote:Tap drill = nominal diameter - pitch

12 x 1.75... tap drill = 10.25

yeah and the drill for an 11 is less meaning you can retap a hole larger asuming it hasn't stripped out beyond the minor diameter of the 12mm bolt

the tap for the 12x1.75 will thread right into the existing 11x1.75 threads and cut them deeper