S10xGN

iTrader: (11)

Hi All,

Got an L-92 block I'm working on... What size chaser tap do I need for the head bolt holes? I always though they were 11mm, but after trying a few random bolts it appears they are some flavor of 10mm. I tried 2 different pitches and neither would thread in more than a round by hand...

Steve - Race Eng

iTrader: (1)

11mm x 2.0

Not something you are going to find at the local hardware store.

serpentnoir

iTrader: (2)

...and the ARP thread chaser is not cheap.

S10xGN

iTrader: (11)

Thanks, Steve! I'll find one, I'm in a very industrial area. If not, there's always McMaster or MSC...

NemeSS

iTrader: (127)

I had one made by machine shop supply vendor I use. I've thought bout havin more made for sale. I think some one besides arp sells a chaser

Gray86hatch

iTrader: (83)

Cut a grove in a stock head bolt and use that to clean out the holes.

Cost is nothing.

Tim

serpentnoir

iTrader: (2)

Nope. Trust me, more difficult to find than you could imagine.

SweetS10V8

iTrader: (4)

I agree with everyone else, this isnt something readilly avaliable...this thread/pitch combo on these heads are almost a unicorn.

S10xGN

iTrader: (11)

Yeah, I'm seeing that now, it appears ARP ($53) is the only option . Guess I'll use an old grooved bolt if need be. BTW, one of my old main bolts fit perfectly so that's an option too...

01ssreda4

iTrader: (96)

I bought the ARP thread chaser for the larger head bolts. Its a nice piece. It has large sections cut out to help collect the debris that comes out of the holes. I also has the threads all the way to the tip, which most taps do not have. I have done two complete motors with it already and it seems to be holding up great. This tool will last you a while.

MattSapp95_T/A

iTrader: (35)

i need to chase the threads on my block too...Does the stock bolt with a groove cut in it work ok?

Thanks

NemeSS

iTrader: (127)

Yes works fine as long as threads on bolt are not damaged

01ssreda4

iTrader: (96)

I tried that and broke my threads out of one of the holes and had to use a Kent Moore time-sert thread repair kit. The problem is the bolt's threads do not pick up all the trash and they have a nub at the end of the bolt causing it to push the trash further down in the hole. You would have to severely modify the bolt to make it as effective as the ARP thread chaser. Its good insurance to have it IMO.

MattSapp95_T/A

iTrader: (35)

those tools are pretty pricey though...anyone want to rent me one for a couple days..??

Randy WS6

iTrader: (69)

I use one of these with my shop vac with a piece of vacuum hose to run down the head bolt hole to clean out the debris after cleaning the threads , works like a charm