Head Studs Too Short

Flex

Flex

Registered User
Hey dudes,

Anyone ever hear of a situation where the ARP head stud is too short to protrude through the head after being installed in the block? A friend sent me some pics of his heads installed on the motor with the studs being about 3/4" below the surface.
 
Mike,

No I checked. He use the 118 mm studs up top. He is telling me his block goes down about 40 mm before it is threaded for the bolts.
 
Mike,

What he is saying is that the holes in the block where the head bolts/studs go are not threaded to the top but go down about 1.5" before the threads start. This results in the studs being way down in the block and not being long enough to come up high enough to protrude though the head bolt bosses in the heads.
 
sounds like a prior mistake

sounds like someone may have stripped a head bolt hole, or maybe bought head bolts that were too long.
They drilled tap holes deeper, drilled clearance holes for 1.5" and then tapped down in the bottom....why they would do this is beyond me.

Where are the original head bolts that your friend pulled out?
were they longer than stock?
you should use them as a guide to see if you can get some correct length APR studs.
 
He told me that the TTY bolts were about 140 mm beneath the heads and that he found a site selling a kit with longer long studs for 96-98 blocks, but they wanted an extra $100. I have never heard of there being a different maching for any 3.8 block, but I have also never seen a 96-98 block.

I guess he is going to have to order longer studs from ARP in order to solve his problem. I did so when I machined my brother's block to use main studs and a windage tray. Expensive but no other choice.
 
OOOOOHHHHH I didn't realize it was a newer block. I guess that explains why I've never seen anything like it.
 
Yeah, if that's a late model 3.8 from a mustang, the head decks are slightly different, and the block is also slightly different. Supposed to be the strongest of the 3.8 blocks Ford Made taking what they did in the SC blocks, with things they had learned since then.
 
98+ 3.8 and all 4.2 blocks are significantly different, and the jury is out on whether or not they are any stronger or better than an SC block.
 
XR7 Dave said:
98+ 3.8 and all 4.2 blocks are significantly different, and the jury is out on whether or not they are any stronger or better than an SC block.
Click to expand...

David,

This is Josh Kessler that is having the problem with the studs. ARP apparently has 137 mm and 160 mm studs available to correct the problem.

Poor kid just spent a week trying to port the heads and open the chambers to bring down his compression from 9.4 to 1 to something more useable. Said he managed to remove 5 cc's worth of material from the chambers. I sent him a CR formula but I don't think he input the numbers right.
 
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