I have found a machine shop through carchitect that has rethreaded blocks before- they said they have very satisfied customers-mostly being high revving imports- many FI cars. The cost is $175 and the turnaround is 2 weeks- not that it takes them 2 weeks to do the work they’re just currently backed up.
The process involves overdrilling the thread hole for the head studs and inserting a steel insert and threading the steel insert to match the thread on the b18c ARP head studs. The biggest advantages I see in this method is A) its made of steel, not aluminum and should have a better tensile strength and b) the new thread made will have a larger surface cohesion to the ARP head studs- which if installed in a block with normal threads dthe studs do not thread all the way through- you dont use the entire thread to connect to the block. The thing I am worried about is the cohesion between the steel insert and the aluminum block. The only reason I am worried about this is due to ignorance- I am weak on my mettalurgy knowlledge and could use some help from some brains out there who would know how well this would hold together. I’m sure if it didnt hold, then this machine shop would not use it, I would just like to know for my own piece of mind that I’m not “playing with fire”. If I get this done, I will leave them a disposable camera and ask if they can snap some pics of the process and will post them up if possible.
although 175 is pretty affordable, wouldnt you feel better getting a new block? ive seen them go for around the same price. then the only thing you’d need to do is redrill for the vtec head right… or hell get a vtec block and/or build it up even
A) its made of steel, not aluminum and should have a better tensile strength and b) the new thread made will have a larger surface cohesion to the ARP head studs
And the insert threads will have a larger surface area in contact with the threaded block, which results in less stress. At a glance, I don’t see a problem with it. Normally, I put steel inserts into all the aluminum parts I make that have threads or clamping forces that are under considerable stress and/or strain. Heck, you could probably do that yourself. It doesn’t seem like a very long job, even if alot of time is taken for the proper precautions.
yep we’re gona do it ourselves- got the kit ordered- cost $75 or so- $50 for the kit and $2 per insert- try and take as many pics of the process as possible. And yes like you said, I have heard of some engine builders removing the aluminum threads and doing this to begin with- thanks for the reply dood